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Xie J, Lu ZN, Bai SH, Cui XF, Lian HY, Xie CY, Wang N, Wang L, Han ZG. Heterochromatin formation and remodeling by IRTKS condensates counteract cellular senescence. EMBO J 2024:10.1038/s44318-024-00212-3. [PMID: 39192031 DOI: 10.1038/s44318-024-00212-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2024] [Revised: 06/30/2024] [Accepted: 07/16/2024] [Indexed: 08/29/2024] Open
Abstract
Heterochromatin, a key component of the eukaryotic nucleus, is fundamental to the regulation of genome stability, gene expression and cellular functions. However, the factors and mechanisms involved in heterochromatin formation and maintenance still remain largely unknown. Here, we show that insulin receptor tyrosine kinase substrate (IRTKS), an I-BAR domain protein, is indispensable for constitutive heterochromatin formation via liquid‒liquid phase separation (LLPS). In particular, IRTKS droplets can infiltrate heterochromatin condensates composed of HP1α and diverse DNA-bound nucleosomes. IRTKS can stabilize HP1α by recruiting the E2 ligase Ubc9 to SUMOylate HP1α, which enables it to form larger phase-separated droplets than unmodified HP1α. Furthermore, IRTKS deficiency leads to loss of heterochromatin, resulting in genome-wide changes in chromatin accessibility and aberrant transcription of repetitive DNA elements. This leads to activation of cGAS-STING pathway and type-I interferon (IFN-I) signaling, as well as to the induction of cellular senescence and senescence-associated secretory phenotype (SASP) responses. Collectively, our findings establish a mechanism by which IRTKS condensates consolidate constitutive heterochromatin, revealing an unexpected role of IRTKS as an epigenetic mediator of cellular senescence.
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Affiliation(s)
- Jia Xie
- Key Laboratory of Systems Biomedicine (Ministry of Education) and State Key Laboratory of Medical Genomics, National Research Center for Translational Medicine at Shanghai, Shanghai Center for Systems Biomedicine, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Zhao-Ning Lu
- Key Laboratory of Systems Biomedicine (Ministry of Education) and State Key Laboratory of Medical Genomics, National Research Center for Translational Medicine at Shanghai, Shanghai Center for Systems Biomedicine, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Shi-Hao Bai
- Key Laboratory of Systems Biomedicine (Ministry of Education) and State Key Laboratory of Medical Genomics, National Research Center for Translational Medicine at Shanghai, Shanghai Center for Systems Biomedicine, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Xiao-Fang Cui
- Key Laboratory of Systems Biomedicine (Ministry of Education) and State Key Laboratory of Medical Genomics, National Research Center for Translational Medicine at Shanghai, Shanghai Center for Systems Biomedicine, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - He-Yuan Lian
- Key Laboratory of Systems Biomedicine (Ministry of Education) and State Key Laboratory of Medical Genomics, National Research Center for Translational Medicine at Shanghai, Shanghai Center for Systems Biomedicine, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Chen-Yi Xie
- Key Laboratory of Systems Biomedicine (Ministry of Education) and State Key Laboratory of Medical Genomics, National Research Center for Translational Medicine at Shanghai, Shanghai Center for Systems Biomedicine, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Na Wang
- Key Laboratory of Systems Biomedicine (Ministry of Education) and State Key Laboratory of Medical Genomics, National Research Center for Translational Medicine at Shanghai, Shanghai Center for Systems Biomedicine, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Lan Wang
- Key Laboratory of Systems Biomedicine (Ministry of Education) and State Key Laboratory of Medical Genomics, National Research Center for Translational Medicine at Shanghai, Shanghai Center for Systems Biomedicine, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Ze-Guang Han
- Key Laboratory of Systems Biomedicine (Ministry of Education) and State Key Laboratory of Medical Genomics, National Research Center for Translational Medicine at Shanghai, Shanghai Center for Systems Biomedicine, Shanghai Jiao Tong University, Shanghai, 200240, China.
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2
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Lopes M, Louzada S, Gama-Carvalho M, Chaves R. Pericentromeric satellite RNAs as flexible protein partners in the regulation of nuclear structure. WILEY INTERDISCIPLINARY REVIEWS. RNA 2024; 15:e1868. [PMID: 38973000 DOI: 10.1002/wrna.1868] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2024] [Revised: 05/17/2024] [Accepted: 05/28/2024] [Indexed: 07/09/2024]
Abstract
Pericentromeric heterochromatin is mainly composed of satellite DNA sequences. Although being historically associated with transcriptional repression, some pericentromeric satellite DNA sequences are transcribed. The transcription events of pericentromeric satellite sequences occur in highly flexible biological contexts. Hence, the apparent randomness of pericentromeric satellite transcription incites the discussion about the attribution of biological functions. However, pericentromeric satellite RNAs have clear roles in the organization of nuclear structure. Silencing pericentromeric heterochromatin depends on pericentromeric satellite RNAs, that, in a feedback mechanism, contribute to the repression of pericentromeric heterochromatin. Moreover, pericentromeric satellite RNAs can also act as scaffolding molecules in condensate subnuclear structures (e.g., nuclear stress bodies). Since the formation/dissociation of nuclear condensates provides cell adaptability, pericentromeric satellite RNAs can be an epigenetic platform for regulating (sub)nuclear structure. We review current knowledge about pericentromeric satellite RNAs that, irrespective of the meaning of biological function, should be functionally addressed in regular and disease settings. This article is categorized under: RNA Methods > RNA Analyses in Cells RNA in Disease and Development > RNA in Disease.
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Affiliation(s)
- Mariana Lopes
- CytoGenomics Lab-Department of Genetics and Biotechnology (DGB), University of Trás os Montes and Alto Douro (UTAD), Vila Real, Portugal
- BioISI: Biosystems & Integrative Sciences Institute, Faculty of Sciences, University of Lisboa, Lisbon, Portugal
| | - Sandra Louzada
- CytoGenomics Lab-Department of Genetics and Biotechnology (DGB), University of Trás os Montes and Alto Douro (UTAD), Vila Real, Portugal
- BioISI: Biosystems & Integrative Sciences Institute, Faculty of Sciences, University of Lisboa, Lisbon, Portugal
| | - Margarida Gama-Carvalho
- BioISI: Biosystems & Integrative Sciences Institute, Faculty of Sciences, University of Lisboa, Lisbon, Portugal
| | - Raquel Chaves
- CytoGenomics Lab-Department of Genetics and Biotechnology (DGB), University of Trás os Montes and Alto Douro (UTAD), Vila Real, Portugal
- BioISI: Biosystems & Integrative Sciences Institute, Faculty of Sciences, University of Lisboa, Lisbon, Portugal
- RISE-Health: Health Research Network, Faculty of Medicine, University of Porto, Porto, Portugal
- CACTMAD: Trás-os-Montes and Alto Douro Academic Clinic Center,University of Trás-os-Montes and Alto Douro (UTAD), Vila Real, Portugal
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3
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von Ehr J, Oberstrass L, Yazgan E, Schnaubelt LI, Blümel N, McNicoll F, Weigand JE, Zarnack K, Müller-McNicoll M, Korn SM, Schlundt A. Arid5a uses disordered extensions of its core ARID domain for distinct DNA- and RNA-recognition and gene regulation. J Biol Chem 2024; 300:107457. [PMID: 38866324 PMCID: PMC11262183 DOI: 10.1016/j.jbc.2024.107457] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2024] [Revised: 05/23/2024] [Accepted: 06/01/2024] [Indexed: 06/14/2024] Open
Abstract
AT-rich interacting domain (ARID)-containing proteins, Arids, are a heterogeneous DNA-binding protein family involved in transcription regulation and chromatin processing. For the member Arid5a, no exact DNA-binding preference has been experimentally defined so far. Additionally, the protein binds to mRNA motifs for transcript stabilization, supposedly through the DNA-binding ARID domain. To date, however, no unbiased RNA motif definition and clear dissection of nucleic acid-binding through the ARID domain have been undertaken. Using NMR-centered biochemistry, we here define the Arid5a DNA preference. Further, high-throughput in vitro binding reveals a consensus RNA-binding motif engaged by the core ARID domain. Finally, transcriptome-wide binding (iCLIP2) reveals that Arid5a has a weak preference for (A)U-rich regions in pre-mRNA transcripts of factors related to RNA processing. We find that the intrinsically disordered regions flanking the ARID domain modulate the specificity and affinity of DNA binding, while they appear crucial for RNA interactions. Ultimately, our data suggest that Arid5a uses its extended ARID domain for bifunctional gene regulation and that the involvement of IDR extensions is a more general feature of Arids in interacting with different nucleic acids at the chromatin-mRNA interface.
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Affiliation(s)
- Julian von Ehr
- Institute for Molecular Biosciences and Biomolecular Resonance Center (BMRZ), Goethe University Frankfurt, Frankfurt, Germany; IMPRS on Cellular Biophysics, Frankfurt, Germany
| | - Lasse Oberstrass
- University of Marburg, Department of Pharmacy, Institute of Pharmaceutical Chemistry, Marburg, Germany
| | - Ege Yazgan
- Institute for Molecular Biosciences, Goethe University Frankfurt, Frankfurt, Germany; Buchmann Institute for Molecular Life Sciences, Goethe University Frankfurt, Frankfurt, Germany
| | - Lara Ina Schnaubelt
- Institute for Molecular Biosciences and Biomolecular Resonance Center (BMRZ), Goethe University Frankfurt, Frankfurt, Germany
| | - Nicole Blümel
- Institute for Molecular Biosciences, Goethe University Frankfurt, Frankfurt, Germany
| | - Francois McNicoll
- Institute for Molecular Biosciences, Goethe University Frankfurt, Frankfurt, Germany
| | - Julia E Weigand
- University of Marburg, Department of Pharmacy, Institute of Pharmaceutical Chemistry, Marburg, Germany
| | - Kathi Zarnack
- Institute for Molecular Biosciences, Goethe University Frankfurt, Frankfurt, Germany; Buchmann Institute for Molecular Life Sciences, Goethe University Frankfurt, Frankfurt, Germany
| | - Michaela Müller-McNicoll
- Institute for Molecular Biosciences, Goethe University Frankfurt, Frankfurt, Germany; Max-Planck Institute for Biophysics, Frankfurt, Germany
| | - Sophie Marianne Korn
- Institute for Molecular Biosciences and Biomolecular Resonance Center (BMRZ), Goethe University Frankfurt, Frankfurt, Germany; Department of Biochemistry and Molecular Biophysics, Columbia University, New York, New York, USA.
| | - Andreas Schlundt
- Institute for Molecular Biosciences and Biomolecular Resonance Center (BMRZ), Goethe University Frankfurt, Frankfurt, Germany; University of Greifswald, Institute of Biochemistry, Greifswald, Germany.
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4
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Inoue T, Bao X, Kageyama T, Sugino Y, Sekito S, Miyachi S, Sasaki T, Getzenberg R. Purine-Rich Element Binding Protein Alpha, a Nuclear Matrix Protein, Has a Role in Prostate Cancer Progression. Int J Mol Sci 2024; 25:6911. [PMID: 39000020 PMCID: PMC11241608 DOI: 10.3390/ijms25136911] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2024] [Revised: 06/20/2024] [Accepted: 06/21/2024] [Indexed: 07/14/2024] Open
Abstract
Solid tumors as well as leukemias and lymphomas show striking changes in nuclear structure including nuclear size and shape, the number and size of nucleoli, and chromatin texture. These alterations have been used in cancer diagnosis and might be related to the altered functional properties of cancer cells. The nuclear matrix (NM) represents the structural composition of the nucleus and consists of nuclear lamins and pore complexes, an internal ribonucleic protein network, and residual nucleoli. In the nuclear microenvironment, the NM is associated with multi-protein complexes, such as basal transcription factors, signaling proteins, histone-modifying factors, and chromatin remodeling machinery directly or indirectly through scaffolding proteins. Therefore, alterations in the composition of NM could result in altered DNA topology and changes in the interaction of various genes, which could then participate in a cascade of the cancer process. Using an androgen-sensitive prostate cancer cell line, LNCaP, and its androgen-independent derivative, LN96, conventional 2D-proteomic analysis of the NM proteins revealed that purine-rich element binding protein alpha (PURα) was detected in the NM proteins and differentially expressed between the cell lines. In this article, we will review the potential role of the molecule in prostate cancer.
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Affiliation(s)
- Takahiro Inoue
- Department of Nephro-Urologic Surgery and Andrology, Mie University Graduate School of Medicine, 2-174, Edobashi, Tsu 514-0001, Japan; (X.B.); (T.K.); (Y.S.); (S.S.); (S.M.); (T.S.)
| | - Xin Bao
- Department of Nephro-Urologic Surgery and Andrology, Mie University Graduate School of Medicine, 2-174, Edobashi, Tsu 514-0001, Japan; (X.B.); (T.K.); (Y.S.); (S.S.); (S.M.); (T.S.)
| | - Takumi Kageyama
- Department of Nephro-Urologic Surgery and Andrology, Mie University Graduate School of Medicine, 2-174, Edobashi, Tsu 514-0001, Japan; (X.B.); (T.K.); (Y.S.); (S.S.); (S.M.); (T.S.)
| | - Yusuke Sugino
- Department of Nephro-Urologic Surgery and Andrology, Mie University Graduate School of Medicine, 2-174, Edobashi, Tsu 514-0001, Japan; (X.B.); (T.K.); (Y.S.); (S.S.); (S.M.); (T.S.)
| | - Sho Sekito
- Department of Nephro-Urologic Surgery and Andrology, Mie University Graduate School of Medicine, 2-174, Edobashi, Tsu 514-0001, Japan; (X.B.); (T.K.); (Y.S.); (S.S.); (S.M.); (T.S.)
| | - Shiori Miyachi
- Department of Nephro-Urologic Surgery and Andrology, Mie University Graduate School of Medicine, 2-174, Edobashi, Tsu 514-0001, Japan; (X.B.); (T.K.); (Y.S.); (S.S.); (S.M.); (T.S.)
| | - Takeshi Sasaki
- Department of Nephro-Urologic Surgery and Andrology, Mie University Graduate School of Medicine, 2-174, Edobashi, Tsu 514-0001, Japan; (X.B.); (T.K.); (Y.S.); (S.S.); (S.M.); (T.S.)
| | - Robert Getzenberg
- Dr. Kiran C Patel College of Allopathic Medicine, Nova Southeastern University, Fort Lauderdale, FL 33328, USA;
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5
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Bujosa P, Reina O, Caballé A, Casas-Lamesa A, Torras-Llort M, Pérez-Roldán J, Nacht AS, Vicent GP, Bernués J, Azorín F. Linker histone H1 regulates homeostasis of heterochromatin-associated cRNAs. Cell Rep 2024; 43:114137. [PMID: 38662543 DOI: 10.1016/j.celrep.2024.114137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Revised: 12/23/2023] [Accepted: 04/08/2024] [Indexed: 06/01/2024] Open
Abstract
Chromatin-associated RNAs (cRNAs) are a poorly characterized fraction of cellular RNAs that co-purify with chromatin. Their full complexity and the mechanisms regulating their packaging and chromatin association remain poorly understood. Here, we address these questions in Drosophila. We find that cRNAs constitute a heterogeneous group of RNA species that is abundant in heterochromatic transcripts. We show that heterochromatic cRNAs interact with the heterogeneous nuclear ribonucleoproteins (hnRNP) hrp36/hrp48 and that depletion of linker histone dH1 impairs this interaction. dH1 depletion induces the accumulation of RNA::DNA hybrids (R-loops) in heterochromatin and, as a consequence, increases retention of heterochromatic cRNAs. These effects correlate with increased RNA polymerase II (RNAPII) occupancy at heterochromatin. Notably, impairing cRNA assembly by depletion of hrp36/hrp48 mimics heterochromatic R-loop accumulation induced by dH1 depletion. We also show that dH1 depletion alters nucleosome organization, increasing accessibility of heterochromatin. Altogether, these perturbations facilitate annealing of cRNAs to the DNA template, enhancing R-loop formation and cRNA retention at heterochromatin.
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Affiliation(s)
- Paula Bujosa
- Institute of Molecular Biology of Barcelona, CSIC, Baldiri Reixac, 4, 08028 Barcelona, Spain; Institute for Research in Biomedicine, IRB Barcelona. The Barcelona Institute of Science and Technology, Baldiri Reixac, 10, 08028 Barcelona, Spain
| | - Oscar Reina
- Institute for Research in Biomedicine, IRB Barcelona. The Barcelona Institute of Science and Technology, Baldiri Reixac, 10, 08028 Barcelona, Spain
| | - Adrià Caballé
- Institute for Research in Biomedicine, IRB Barcelona. The Barcelona Institute of Science and Technology, Baldiri Reixac, 10, 08028 Barcelona, Spain
| | - Anna Casas-Lamesa
- Institute of Molecular Biology of Barcelona, CSIC, Baldiri Reixac, 4, 08028 Barcelona, Spain; Institute for Research in Biomedicine, IRB Barcelona. The Barcelona Institute of Science and Technology, Baldiri Reixac, 10, 08028 Barcelona, Spain
| | - Mònica Torras-Llort
- Institute of Molecular Biology of Barcelona, CSIC, Baldiri Reixac, 4, 08028 Barcelona, Spain; Institute for Research in Biomedicine, IRB Barcelona. The Barcelona Institute of Science and Technology, Baldiri Reixac, 10, 08028 Barcelona, Spain
| | - Juan Pérez-Roldán
- Institute of Molecular Biology of Barcelona, CSIC, Baldiri Reixac, 4, 08028 Barcelona, Spain; Institute for Research in Biomedicine, IRB Barcelona. The Barcelona Institute of Science and Technology, Baldiri Reixac, 10, 08028 Barcelona, Spain
| | - Ana Silvina Nacht
- Centre de Regulació Genòmica (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Guillermo P Vicent
- Institute of Molecular Biology of Barcelona, CSIC, Baldiri Reixac, 4, 08028 Barcelona, Spain; Centre de Regulació Genòmica (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Jordi Bernués
- Institute of Molecular Biology of Barcelona, CSIC, Baldiri Reixac, 4, 08028 Barcelona, Spain; Institute for Research in Biomedicine, IRB Barcelona. The Barcelona Institute of Science and Technology, Baldiri Reixac, 10, 08028 Barcelona, Spain.
| | - Fernando Azorín
- Institute of Molecular Biology of Barcelona, CSIC, Baldiri Reixac, 4, 08028 Barcelona, Spain; Institute for Research in Biomedicine, IRB Barcelona. The Barcelona Institute of Science and Technology, Baldiri Reixac, 10, 08028 Barcelona, Spain.
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6
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Patowary A, Zhang P, Jops C, Vuong CK, Ge X, Hou K, Kim M, Gong N, Margolis M, Vo D, Wang X, Liu C, Pasaniuc B, Li JJ, Gandal MJ, de la Torre-Ubieta L. Developmental isoform diversity in the human neocortex informs neuropsychiatric risk mechanisms. Science 2024; 384:eadh7688. [PMID: 38781356 DOI: 10.1126/science.adh7688] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Accepted: 03/13/2024] [Indexed: 05/25/2024]
Abstract
RNA splicing is highly prevalent in the brain and has strong links to neuropsychiatric disorders; yet, the role of cell type-specific splicing and transcript-isoform diversity during human brain development has not been systematically investigated. In this work, we leveraged single-molecule long-read sequencing to deeply profile the full-length transcriptome of the germinal zone and cortical plate regions of the developing human neocortex at tissue and single-cell resolution. We identified 214,516 distinct isoforms, of which 72.6% were novel (not previously annotated in Gencode version 33), and uncovered a substantial contribution of transcript-isoform diversity-regulated by RNA binding proteins-in defining cellular identity in the developing neocortex. We leveraged this comprehensive isoform-centric gene annotation to reprioritize thousands of rare de novo risk variants and elucidate genetic risk mechanisms for neuropsychiatric disorders.
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Affiliation(s)
- Ashok Patowary
- Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90095, USA
- Semel Institute for Neuroscience and Human Behavior, University of California Los Angeles, Los Angeles, CA 90095, USA
- Intellectual and Developmental Disabilities Research Center, Semel Institute for Neuroscience and Human Behavior, University of California Los Angeles, Los Angeles, CA 90095, USA
- Department of Human Genetics, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90095, USA
| | - Pan Zhang
- Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90095, USA
- Semel Institute for Neuroscience and Human Behavior, University of California Los Angeles, Los Angeles, CA 90095, USA
- Intellectual and Developmental Disabilities Research Center, Semel Institute for Neuroscience and Human Behavior, University of California Los Angeles, Los Angeles, CA 90095, USA
- Department of Human Genetics, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90095, USA
| | - Connor Jops
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- Lifespan Brain Institute at Penn Med and the Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Celine K Vuong
- Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90095, USA
- Semel Institute for Neuroscience and Human Behavior, University of California Los Angeles, Los Angeles, CA 90095, USA
- Intellectual and Developmental Disabilities Research Center, Semel Institute for Neuroscience and Human Behavior, University of California Los Angeles, Los Angeles, CA 90095, USA
| | - Xinzhou Ge
- Department of Statistics, University of California Los Angeles, Los Angeles, CA 90095, USA
| | - Kangcheng Hou
- Bioinformatics Interdepartmental Program, University of California Los Angeles, Los Angeles, CA 90095, USA
| | - Minsoo Kim
- Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90095, USA
- Semel Institute for Neuroscience and Human Behavior, University of California Los Angeles, Los Angeles, CA 90095, USA
- Department of Human Genetics, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90095, USA
| | - Naihua Gong
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Michael Margolis
- Department of Human Genetics, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90095, USA
| | - Daniel Vo
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- Lifespan Brain Institute at Penn Med and the Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Xusheng Wang
- Department of Genetics, Genomics and Informatics, University of Tennessee Health Science Center, Memphis, TN 38103, USA
- Center for Proteomics and Metabolomics, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Chunyu Liu
- Department of Psychiatry, SUNY Upstate Medical University, Syracuse, NY 13210, USA
- Center for Medical Genetics and Hunan Key Laboratory of Medical Genetics, School of Life Sciences, Central South University, Changsha, Hunan 410008, China
| | - Bogdan Pasaniuc
- Department of Human Genetics, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90095, USA
- Bioinformatics Interdepartmental Program, University of California Los Angeles, Los Angeles, CA 90095, USA
- Department of Pathology and Laboratory Medicine, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90095, USA
- Institute for Precision Health, University of California Los Angeles, Los Angeles, CA 90095, USA
- Department of Computational Medicine, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90095, USA
| | - Jingyi Jessica Li
- Department of Human Genetics, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90095, USA
- Department of Statistics, University of California Los Angeles, Los Angeles, CA 90095, USA
- Bioinformatics Interdepartmental Program, University of California Los Angeles, Los Angeles, CA 90095, USA
- Department of Computational Medicine, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90095, USA
- Department of Biostatistics, University of California Los Angeles, Los Angeles, CA 90095, USA
| | - Michael J Gandal
- Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90095, USA
- Semel Institute for Neuroscience and Human Behavior, University of California Los Angeles, Los Angeles, CA 90095, USA
- Intellectual and Developmental Disabilities Research Center, Semel Institute for Neuroscience and Human Behavior, University of California Los Angeles, Los Angeles, CA 90095, USA
- Department of Human Genetics, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90095, USA
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- Lifespan Brain Institute at Penn Med and the Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Luis de la Torre-Ubieta
- Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90095, USA
- Semel Institute for Neuroscience and Human Behavior, University of California Los Angeles, Los Angeles, CA 90095, USA
- Intellectual and Developmental Disabilities Research Center, Semel Institute for Neuroscience and Human Behavior, University of California Los Angeles, Los Angeles, CA 90095, USA
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7
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Forcella P, Ifflander N, Rolando C, Balta EA, Lampada A, Giachino C, Mukhtar T, Bock T, Taylor V. SAFB regulates hippocampal stem cell fate by targeting Drosha to destabilize Nfib mRNA. eLife 2024; 13:e74940. [PMID: 38722021 PMCID: PMC11149935 DOI: 10.7554/elife.74940] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Accepted: 05/08/2024] [Indexed: 06/05/2024] Open
Abstract
Neural stem cells (NSCs) are multipotent and correct fate determination is crucial to guarantee brain formation and homeostasis. How NSCs are instructed to generate neuronal or glial progeny is not well understood. Here, we addressed how murine adult hippocampal NSC fate is regulated and described how scaffold attachment factor B (SAFB) blocks oligodendrocyte production to enable neuron generation. We found that SAFB prevents NSC expression of the transcription factor nuclear factor I/B (NFIB) by binding to sequences in the Nfib mRNA and enhancing Drosha-dependent cleavage of the transcripts. We show that increasing SAFB expression prevents oligodendrocyte production by multipotent adult NSCs, and conditional deletion of Safb increases NFIB expression and oligodendrocyte formation in the adult hippocampus. Our results provide novel insights into a mechanism that controls Drosha functions for selective regulation of NSC fate by modulating the post-transcriptional destabilization of Nfib mRNA in a lineage-specific manner.
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Affiliation(s)
- Pascal Forcella
- Department of Biomedicine, University of BaselBaselSwitzerland
| | | | - Chiara Rolando
- Department of Biomedicine, University of BaselBaselSwitzerland
- Department of Biosciences, University of MilanMilanItaly
| | - Elli-Anna Balta
- Department of Biomedicine, University of BaselBaselSwitzerland
| | | | | | - Tanzila Mukhtar
- Department of Biomedicine, University of BaselBaselSwitzerland
| | - Thomas Bock
- Proteomics Core Facility, Biozentrum, University of BaselBaselSwitzerland
| | - Verdon Taylor
- Department of Biomedicine, University of BaselBaselSwitzerland
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8
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Choudhury R, Venkateswaran Venkatasubramani A, Hua J, Borsò M, Franconi C, Kinkley S, Forné I, Imhof A. The role of RNA in the maintenance of chromatin domains as revealed by antibody-mediated proximity labelling coupled to mass spectrometry. eLife 2024; 13:e95718. [PMID: 38717135 PMCID: PMC11147508 DOI: 10.7554/elife.95718] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2023] [Accepted: 04/26/2024] [Indexed: 06/04/2024] Open
Abstract
Eukaryotic chromatin is organized into functional domains, that are characterized by distinct proteomic compositions and specific nuclear positions. In contrast to cellular organelles surrounded by lipid membranes, the composition of distinct chromatin domains is rather ill described and highly dynamic. To gain molecular insight into these domains and explore their composition, we developed an antibody-based proximity biotinylation method targeting the RNA and proteins constituents. The method that we termed antibody-mediated proximity labelling coupled to mass spectrometry (AMPL-MS) does not require the expression of fusion proteins and therefore constitutes a versatile and very sensitive method to characterize the composition of chromatin domains based on specific signature proteins or histone modifications. To demonstrate the utility of our approach we used AMPL-MS to characterize the molecular features of the chromocenter as well as the chromosome territory containing the hyperactive X chromosome in Drosophila. This analysis identified a number of known RNA-binding proteins in proximity of the hyperactive X and the centromere, supporting the accuracy of our method. In addition, it enabled us to characterize the role of RNA in the formation of these nuclear bodies. Furthermore, our method identified a new set of RNA molecules associated with the Drosophila centromere. Characterization of these novel molecules suggested the formation of R-loops in centromeres, which we validated using a novel probe for R-loops in Drosophila. Taken together, AMPL-MS improves the selectivity and specificity of proximity ligation allowing for novel discoveries of weak protein-RNA interactions in biologically diverse domains.
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Affiliation(s)
- Rupam Choudhury
- Department of Molecular Biology, Biomedical Center Munich, Ludwig-Maximilians UniversityPlanegg-MartinsriedGermany
| | - Anuroop Venkateswaran Venkatasubramani
- Department of Molecular Biology, Biomedical Center Munich, Ludwig-Maximilians UniversityPlanegg-MartinsriedGermany
- Graduate School of Quantitative Biosciences (QBM), Ludwig-Maximilians-Universität MünchenMunichGermany
| | - Jie Hua
- Department of Molecular Biology, Biomedical Center Munich, Ludwig-Maximilians UniversityPlanegg-MartinsriedGermany
| | - Marco Borsò
- Protein Analysis Unit, Biomedical Center (BMC), Faculty of Medicine, Ludwig-Maximilians, University (LMU) MunichPlanegg-MartinsriedGermany
| | - Celeste Franconi
- Chromatin Structure and Function group, Department of Computational Molecular Biology, Max Planck Institute for Molecular GeneticsBerlinGermany
| | - Sarah Kinkley
- Chromatin Structure and Function group, Department of Computational Molecular Biology, Max Planck Institute for Molecular GeneticsBerlinGermany
| | - Ignasi Forné
- Protein Analysis Unit, Biomedical Center (BMC), Faculty of Medicine, Ludwig-Maximilians, University (LMU) MunichPlanegg-MartinsriedGermany
| | - Axel Imhof
- Department of Molecular Biology, Biomedical Center Munich, Ludwig-Maximilians UniversityPlanegg-MartinsriedGermany
- Protein Analysis Unit, Biomedical Center (BMC), Faculty of Medicine, Ludwig-Maximilians, University (LMU) MunichPlanegg-MartinsriedGermany
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9
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Hong Y, Bie L, Zhang T, Yan X, Jin G, Chen Z, Wang Y, Li X, Pei G, Zhang Y, Hong Y, Gong L, Li P, Xie W, Zhu Y, Shen X, Liu N. SAFB restricts contact domain boundaries associated with L1 chimeric transcription. Mol Cell 2024; 84:1637-1650.e10. [PMID: 38604171 DOI: 10.1016/j.molcel.2024.03.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 02/05/2024] [Accepted: 03/19/2024] [Indexed: 04/13/2024]
Abstract
Long interspersed element-1 (LINE-1 or L1) comprises 17% of the human genome, continuously generates genetic variations, and causes disease in certain cases. However, the regulation and function of L1 remain poorly understood. Here, we uncover that L1 can enrich RNA polymerase IIs (RNA Pol IIs), express L1 chimeric transcripts, and create contact domain boundaries in human cells. This impact of L1 is restricted by a nuclear matrix protein scaffold attachment factor B (SAFB) that recognizes transcriptionally active L1s by binding L1 transcripts to inhibit RNA Pol II enrichment. Acute inhibition of RNA Pol II transcription abolishes the domain boundaries associated with L1 chimeric transcripts, indicating a transcription-dependent mechanism. Deleting L1 impairs domain boundary formation, and L1 insertions during evolution have introduced species-specific domain boundaries. Our data show that L1 can create RNA Pol II-enriched regions that alter genome organization and that SAFB regulates L1 and RNA Pol II activity to preserve gene regulation.
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Affiliation(s)
- Yaqiang Hong
- Tsinghua University-Peking University Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Luyao Bie
- Tsinghua University-Peking University Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Tao Zhang
- Tsinghua University-Peking University Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Xiaohan Yan
- Tsinghua University-Peking University Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Guangpu Jin
- Tsinghua University-Peking University Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Zhuo Chen
- Tsinghua University-Peking University Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Yang Wang
- Tsinghua University-Peking University Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Xiufeng Li
- Tsinghua University-Peking University Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Gaofeng Pei
- Tsinghua University-Peking University Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Yongyan Zhang
- Tsinghua University-Peking University Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Yantao Hong
- Tsinghua University-Peking University Joint Center for Life Sciences, School of Medicine, Tsinghua University, Beijing 100084, China
| | - Liang Gong
- Liangzhu Laboratory, Zhejiang University Medical Center, Hangzhou 311121, China
| | - Pilong Li
- Tsinghua University-Peking University Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Wei Xie
- Tsinghua University-Peking University Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Yanfen Zhu
- International Institutes of Medicine, The Fourth Affiliated Hospital of Zhejiang University School of Medicine, Yiwu 322000, China
| | - Xiaohua Shen
- Tsinghua University-Peking University Joint Center for Life Sciences, School of Medicine, Tsinghua University, Beijing 100084, China
| | - Nian Liu
- Tsinghua University-Peking University Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China.
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10
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Han X, Xing L, Hong Y, Zhang X, Hao B, Lu JY, Huang M, Wang Z, Ma S, Zhan G, Li T, Hao X, Tao Y, Li G, Zhou S, Zheng Z, Shao W, Zeng Y, Ma D, Zhang W, Xie Z, Deng H, Yan J, Deng W, Shen X. Nuclear RNA homeostasis promotes systems-level coordination of cell fate and senescence. Cell Stem Cell 2024; 31:694-716.e11. [PMID: 38631356 DOI: 10.1016/j.stem.2024.03.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Revised: 02/01/2024] [Accepted: 03/26/2024] [Indexed: 04/19/2024]
Abstract
Understanding cellular coordination remains a challenge despite knowledge of individual pathways. The RNA exosome, targeting a wide range of RNA substrates, is often downregulated in cellular senescence. Utilizing an auxin-inducible system, we observed that RNA exosome depletion in embryonic stem cells significantly affects the transcriptome and proteome, causing pluripotency loss and pre-senescence onset. Mechanistically, exosome depletion triggers acute nuclear RNA aggregation, disrupting nuclear RNA-protein equilibrium. This disturbance limits nuclear protein availability and hinders polymerase initiation and engagement, reducing gene transcription. Concurrently, it promptly disrupts nucleolar transcription, ribosomal processes, and nuclear exporting, resulting in a translational shutdown. Prolonged exosome depletion induces nuclear structural changes resembling senescent cells, including aberrant chromatin compaction, chromocenter disassembly, and intensified heterochromatic foci. These effects suggest that the dynamic turnover of nuclear RNA orchestrates crosstalk between essential processes to optimize cellular function. Disruptions in nuclear RNA homeostasis result in systemic functional decline, altering the cell state and promoting senescence.
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Affiliation(s)
- Xue Han
- State Key Laboratory of Membrane Biology, Beijing Frontier Research Center for Biological Structure, Tsinghua-Peking Joint Center for Life Sciences, School of Basic Medical Sciences, Tsinghua University, Beijing 100084, China
| | - Linqing Xing
- State Key Laboratory of Membrane Biology, Beijing Frontier Research Center for Biological Structure, Tsinghua-Peking Joint Center for Life Sciences, School of Basic Medical Sciences, Tsinghua University, Beijing 100084, China
| | - Yantao Hong
- State Key Laboratory of Membrane Biology, Beijing Frontier Research Center for Biological Structure, Tsinghua-Peking Joint Center for Life Sciences, School of Basic Medical Sciences, Tsinghua University, Beijing 100084, China
| | - Xuechun Zhang
- State Key Laboratory of Membrane Biology, Beijing Frontier Research Center for Biological Structure, Tsinghua-Peking Joint Center for Life Sciences, School of Basic Medical Sciences, Tsinghua University, Beijing 100084, China
| | - Bo Hao
- SXMU-Tsinghua Collaborative Innovation Center for Frontier Medicine, Shanxi Medical University, Taiyuan, Shanxi 030001, China
| | - J Yuyang Lu
- State Key Laboratory of Membrane Biology, Beijing Frontier Research Center for Biological Structure, Tsinghua-Peking Joint Center for Life Sciences, School of Basic Medical Sciences, Tsinghua University, Beijing 100084, China
| | - Mengyuan Huang
- State Key Laboratory of Membrane Biology, Beijing Frontier Research Center for Biological Structure, Tsinghua-Peking Joint Center for Life Sciences, School of Basic Medical Sciences, Tsinghua University, Beijing 100084, China
| | - Zuhui Wang
- Biomedical Pioneering Innovation Center (BIOPIC), Beijing Advanced Innovation Center for Genomics (ICG), Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China
| | - Shaoqian Ma
- State Key Laboratory of Membrane Biology, Beijing Frontier Research Center for Biological Structure, Tsinghua-Peking Joint Center for Life Sciences, School of Basic Medical Sciences, Tsinghua University, Beijing 100084, China
| | - Ge Zhan
- State Key Laboratory of Membrane Biology, Beijing Frontier Research Center for Biological Structure, Tsinghua-Peking Joint Center for Life Sciences, School of Basic Medical Sciences, Tsinghua University, Beijing 100084, China
| | - Tong Li
- State Key Laboratory of Membrane Biology, Beijing Frontier Research Center for Biological Structure, Tsinghua-Peking Joint Center for Life Sciences, School of Basic Medical Sciences, Tsinghua University, Beijing 100084, China
| | - Xiaowen Hao
- State Key Laboratory of Membrane Biology, Beijing Frontier Research Center for Biological Structure, Tsinghua-Peking Joint Center for Life Sciences, School of Basic Medical Sciences, Tsinghua University, Beijing 100084, China
| | - Yibing Tao
- State Key Laboratory of Membrane Biology, Beijing Frontier Research Center for Biological Structure, Tsinghua-Peking Joint Center for Life Sciences, School of Basic Medical Sciences, Tsinghua University, Beijing 100084, China
| | - Guanwen Li
- State Key Laboratory of Membrane Biology, Beijing Frontier Research Center for Biological Structure, Tsinghua-Peking Joint Center for Life Sciences, School of Basic Medical Sciences, Tsinghua University, Beijing 100084, China
| | - Shuqin Zhou
- State Key Laboratory of Membrane Biology, Beijing Frontier Research Center for Biological Structure, Tsinghua-Peking Joint Center for Life Sciences, School of Basic Medical Sciences, Tsinghua University, Beijing 100084, China
| | - Zheng Zheng
- State Key Laboratory of Membrane Biology, Beijing Frontier Research Center for Biological Structure, Tsinghua-Peking Joint Center for Life Sciences, School of Basic Medical Sciences, Tsinghua University, Beijing 100084, China
| | - Wen Shao
- State Key Laboratory of Membrane Biology, Beijing Frontier Research Center for Biological Structure, Tsinghua-Peking Joint Center for Life Sciences, School of Basic Medical Sciences, Tsinghua University, Beijing 100084, China
| | - Yitian Zeng
- State Key Laboratory of Membrane Biology, Beijing Frontier Research Center for Biological Structure, Tsinghua-Peking Joint Center for Life Sciences, School of Basic Medical Sciences, Tsinghua University, Beijing 100084, China
| | - Dacheng Ma
- MOE Key Laboratory of Bioinformatics and Bioinformatics Division, Center for Synthetic and Systems Biology, Department of Automation, Beijing National Research Center for Information Science and Technology, Tsinghua University, Beijing 100084, China
| | - Wenhao Zhang
- MOE Key Laboratory of Bioinformatics, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Zhen Xie
- MOE Key Laboratory of Bioinformatics and Bioinformatics Division, Center for Synthetic and Systems Biology, Department of Automation, Beijing National Research Center for Information Science and Technology, Tsinghua University, Beijing 100084, China
| | - Haiteng Deng
- MOE Key Laboratory of Bioinformatics, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Jiangwei Yan
- SXMU-Tsinghua Collaborative Innovation Center for Frontier Medicine, Shanxi Medical University, Taiyuan, Shanxi 030001, China
| | - Wulan Deng
- Biomedical Pioneering Innovation Center (BIOPIC), Beijing Advanced Innovation Center for Genomics (ICG), Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China
| | - Xiaohua Shen
- State Key Laboratory of Membrane Biology, Beijing Frontier Research Center for Biological Structure, Tsinghua-Peking Joint Center for Life Sciences, School of Basic Medical Sciences, Tsinghua University, Beijing 100084, China; SXMU-Tsinghua Collaborative Innovation Center for Frontier Medicine, Shanxi Medical University, Taiyuan, Shanxi 030001, China.
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11
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Zocher S, McCloskey A, Karasinsky A, Schulte R, Friedrich U, Lesche M, Rund N, Gage FH, Hetzer MW, Toda T. Lifelong persistence of nuclear RNAs in the mouse brain. Science 2024; 384:53-59. [PMID: 38574132 PMCID: PMC7615865 DOI: 10.1126/science.adf3481] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2022] [Accepted: 02/02/2024] [Indexed: 04/06/2024]
Abstract
Genomic DNA that resides in the nuclei of mammalian neurons can be as old as the organism itself. The life span of nuclear RNAs, which are critical for proper chromatin architecture and transcription regulation, has not been determined in adult tissues. In this work, we identified and characterized nuclear RNAs that do not turn over for at least 2 years in a subset of postnatally born cells in the mouse brain. These long-lived RNAs were stably retained in nuclei in a neural cell type-specific manner and were required for the maintenance of heterochromatin. Thus, the life span of neural cells may depend on both the molecular longevity of DNA for the storage of genetic information and also the extreme stability of RNA for the functional organization of chromatin.
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Affiliation(s)
- Sara Zocher
- Nuclear Architecture in Neural Plasticity and Aging, German Center for Neurodegenerative Diseases (DZNE), Dresden 01307, Germany
| | - Asako McCloskey
- Molecular and Cell Biology Laboratory, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA
- Kura Oncology, Inc., 5510 Morehouse Dr., San Diego, CA 92121, USA
| | - Anne Karasinsky
- Nuclear Architecture in Neural Plasticity and Aging, German Center for Neurodegenerative Diseases (DZNE), Dresden 01307, Germany
| | - Roberta Schulte
- Molecular and Cell Biology Laboratory, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Ulrike Friedrich
- DRESDEN-concept Genome Center, Technology Platform at the Center for Molecular and Cellular Bioengineering (CMCB), Technische Universität Dresden, Fetscherstr. 105, Dresden 01307, Germany
- German Center for Diabetes Research (DZD e.V.), 85764 Neuherberg, Germany
- Paul Langerhans Institute Dresden of the Helmholtz Center Munich, University Hospital and Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, 01307 Dresden, Germany
| | - Mathias Lesche
- DRESDEN-concept Genome Center, Technology Platform at the Center for Molecular and Cellular Bioengineering (CMCB), Technische Universität Dresden, Fetscherstr. 105, Dresden 01307, Germany
| | - Nicole Rund
- Nuclear Architecture in Neural Plasticity and Aging, German Center for Neurodegenerative Diseases (DZNE), Dresden 01307, Germany
| | - Fred H. Gage
- Laboratory of Genetics, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Martin W. Hetzer
- Institute of Science and Technology Austria (ISTA), 3400 Klosterneuburg, Austria
| | - Tomohisa Toda
- Nuclear Architecture in Neural Plasticity and Aging, German Center for Neurodegenerative Diseases (DZNE), Dresden 01307, Germany
- Laboratory of Neural Epigenomics, Institute of Medical Physics and Micro-tissue Engineering, Faculty of Medicine, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen 91054, Germany
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12
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Guo JK, Blanco MR, Walkup WG, Bonesteele G, Urbinati CR, Banerjee AK, Chow A, Ettlin O, Strehle M, Peyda P, Amaya E, Trinh V, Guttman M. Denaturing purifications demonstrate that PRC2 and other widely reported chromatin proteins do not appear to bind directly to RNA in vivo. Mol Cell 2024; 84:1271-1289.e12. [PMID: 38387462 PMCID: PMC10997485 DOI: 10.1016/j.molcel.2024.01.026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2023] [Revised: 12/01/2023] [Accepted: 01/30/2024] [Indexed: 02/24/2024]
Abstract
Polycomb repressive complex 2 (PRC2) is reported to bind to many RNAs and has become a central player in reports of how long non-coding RNAs (lncRNAs) regulate gene expression. Yet, there is a growing discrepancy between the biochemical evidence supporting specific lncRNA-PRC2 interactions and functional evidence demonstrating that PRC2 is often dispensable for lncRNA function. Here, we revisit the evidence supporting RNA binding by PRC2 and show that many reported interactions may not occur in vivo. Using denaturing purification of in vivo crosslinked RNA-protein complexes in human and mouse cell lines, we observe a loss of detectable RNA binding to PRC2 and chromatin-associated proteins previously reported to bind RNA (CTCF, YY1, and others), despite accurately mapping bona fide RNA-binding sites across others (SPEN, TET2, and others). Taken together, these results argue for a critical re-evaluation of the broad role of RNA binding to orchestrate various chromatin regulatory mechanisms.
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Affiliation(s)
- Jimmy K Guo
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA; Keck School of Medicine, University of Southern California, Los Angeles, CA 90089, USA
| | - Mario R Blanco
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA.
| | - Ward G Walkup
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA
| | - Grant Bonesteele
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA
| | - Carl R Urbinati
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA; Department of Biology, Loyola Marymount University, Los Angeles, CA 90045, USA
| | - Abhik K Banerjee
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA; Keck School of Medicine, University of Southern California, Los Angeles, CA 90089, USA
| | - Amy Chow
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA
| | - Olivia Ettlin
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA
| | - Mackenzie Strehle
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA
| | - Parham Peyda
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA
| | - Enrique Amaya
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA
| | - Vickie Trinh
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA
| | - Mitchell Guttman
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA.
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13
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Tang L, Liao J, Hill MC, Hu J, Zhao Y, Ellinor P, Li M. MMCT-Loop: a mix model-based pipeline for calling targeted 3D chromatin loops. Nucleic Acids Res 2024; 52:e25. [PMID: 38281134 PMCID: PMC10954456 DOI: 10.1093/nar/gkae029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2023] [Revised: 12/03/2023] [Accepted: 01/12/2024] [Indexed: 01/30/2024] Open
Abstract
Protein-specific Chromatin Conformation Capture (3C)-based technologies have become essential for identifying distal genomic interactions with critical roles in gene regulation. The standard techniques include Chromatin Interaction Analysis by Paired-End Tag (ChIA-PET), in situ Hi-C followed by chromatin immunoprecipitation (HiChIP) also known as PLAC-seq. To identify chromatin interactions from these data, a variety of computational methods have emerged. Although these state-of-art methods address many issues with loop calling, only few methods can fit different data types simultaneously, and the accuracy as well as the efficiency these approaches remains limited. Here we have generated a pipeline, MMCT-Loop, which ensures the accurate identification of strong loops as well as dynamic or weak loops through a mixed model. MMCT-Loop outperforms existing methods in accuracy, and the detected loops show higher activation functionality. To highlight the utility of MMCT-Loop, we applied it to conformational data derived from neural stem cell (NSCs) and uncovered several previously unidentified regulatory regions for key master regulators of stem cell identity. MMCT-Loop is an accurate and efficient loop caller for targeted conformation capture data, which supports raw data or pre-processed valid pairs as input, the output interactions are formatted and easily uploaded to a genome browser for visualization.
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Affiliation(s)
- Li Tang
- Hunan Provincial Key Lab on Bioinformatics, School of Computer Science and Engineering, Central South University, Changsha 410083, China
| | - Jiaqi Liao
- Hunan Provincial Key Lab on Bioinformatics, School of Computer Science and Engineering, Central South University, Changsha 410083, China
| | - Matthew C Hill
- Cardiovascular Research Center, Massachusetts General Hospital, Boston, MA 02129, USA
- Cardiovascular Disease Initiative, The Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA
| | - Jiaxin Hu
- Hunan Provincial Key Lab on Bioinformatics, School of Computer Science and Engineering, Central South University, Changsha 410083, China
| | - Yichao Zhao
- Hunan Provincial Key Lab on Bioinformatics, School of Computer Science and Engineering, Central South University, Changsha 410083, China
| | - Patrick T Ellinor
- Cardiovascular Research Center, Massachusetts General Hospital, Boston, MA 02129, USA
- Cardiovascular Disease Initiative, The Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA
| | - Min Li
- Hunan Provincial Key Lab on Bioinformatics, School of Computer Science and Engineering, Central South University, Changsha 410083, China
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14
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Wahl N, Espeso-Gil S, Chietera P, Nagel A, Laighneach A, Morris DW, Rajarajan P, Akbarian S, Dechant G, Apostolova G. SATB2 organizes the 3D genome architecture of cognition in cortical neurons. Mol Cell 2024; 84:621-639.e9. [PMID: 38244545 PMCID: PMC10923151 DOI: 10.1016/j.molcel.2023.12.024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Revised: 10/02/2023] [Accepted: 12/15/2023] [Indexed: 01/22/2024]
Abstract
The DNA-binding protein SATB2 is genetically linked to human intelligence. We studied its influence on the three-dimensional (3D) epigenome by mapping chromatin interactions and accessibility in control versus SATB2-deficient cortical neurons. We find that SATB2 affects the chromatin looping between enhancers and promoters of neuronal-activity-regulated genes, thus influencing their expression. It also alters A/B compartments, topologically associating domains, and frequently interacting regions. Genes linked to SATB2-dependent 3D genome changes are implicated in highly specialized neuronal functions and contribute to cognitive ability and risk for neuropsychiatric and neurodevelopmental disorders. Non-coding DNA regions with a SATB2-dependent structure are enriched for common variants associated with educational attainment, intelligence, and schizophrenia. Our data establish SATB2 as a cell-type-specific 3D genome modulator, which operates both independently and in cooperation with CCCTC-binding factor (CTCF) to set up the chromatin landscape of pyramidal neurons for cognitive processes.
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Affiliation(s)
- Nico Wahl
- Institute for Neuroscience, Medical University of Innsbruck, Innsbruck 6020, Austria.
| | - Sergio Espeso-Gil
- Institute for Neuroscience, Medical University of Innsbruck, Innsbruck 6020, Austria; Department of Psychiatry, Friedman Brain Institute, Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Paola Chietera
- Institute for Neuroscience, Medical University of Innsbruck, Innsbruck 6020, Austria
| | - Amelie Nagel
- Institute for Neuroscience, Medical University of Innsbruck, Innsbruck 6020, Austria
| | - Aodán Laighneach
- Centre for Neuroimaging, Cognition and Genomics (NICOG), School of Biological and Chemical Sciences, University of Galway, Galway, H91 TK33, Ireland
| | - Derek W Morris
- Centre for Neuroimaging, Cognition and Genomics (NICOG), School of Biological and Chemical Sciences, University of Galway, Galway, H91 TK33, Ireland
| | - Prashanth Rajarajan
- Department of Psychiatry, Friedman Brain Institute, Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Schahram Akbarian
- Department of Psychiatry, Friedman Brain Institute, Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Georg Dechant
- Institute for Neuroscience, Medical University of Innsbruck, Innsbruck 6020, Austria.
| | - Galina Apostolova
- Institute for Neuroscience, Medical University of Innsbruck, Innsbruck 6020, Austria.
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15
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Ingersoll S, Trouth A, Luo X, Espinoza A, Wen J, Tucker J, Astatike K, Phiel CJ, Kutateladze TG, Wu TP, Ramachandran S, Ren X. Sparse CBX2 nucleates many Polycomb proteins to promote facultative heterochromatinization of Polycomb target genes. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.05.578969. [PMID: 38370615 PMCID: PMC10871256 DOI: 10.1101/2024.02.05.578969] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/20/2024]
Abstract
Facultative heterochromatinization of genomic regulators by Polycomb repressive complex (PRC) 1 and 2 is essential in development and differentiation; however, the underlying molecular mechanisms remain obscure. Using genetic engineering, molecular approaches, and live-cell single-molecule imaging, we quantify the number of proteins within condensates formed through liquid-liquid phase separation (LLPS) and find that in mouse embryonic stem cells (mESCs), approximately 3 CBX2 proteins nucleate many PRC1 and PRC2 subunits to form one non-stoichiometric condensate. We demonstrate that sparse CBX2 prevents Polycomb proteins from migrating to constitutive heterochromatin, demarcates the spatial boundaries of facultative heterochromatin, controls the deposition of H3K27me3, regulates transcription, and impacts cellular differentiation. Furthermore, we show that LLPS of CBX2 is required for the demarcation and deposition of H3K27me3 and is essential for cellular differentiation. Our findings uncover new functional roles of LLPS in the formation of facultative heterochromatin and unravel a new mechanism by which low-abundant proteins nucleate many other proteins to form compartments that enable them to execute their functions.
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Affiliation(s)
- Steven Ingersoll
- Department of Chemistry, University of Colorado Denver, Denver, CO 80217-3364, USA
| | - Abby Trouth
- Department of Biochemistry and Molecular Genetics, University of Colorado School of Medicine, Aurora, CO, USA
| | - Xinlong Luo
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - Axel Espinoza
- Department of Integrative Biology, University of Colorado Denver, CO 80217-3364, USA
| | - Joey Wen
- Department of Chemistry, University of Colorado Denver, Denver, CO 80217-3364, USA
| | - Joseph Tucker
- Department of Integrative Biology, University of Colorado Denver, CO 80217-3364, USA
| | - Kalkidan Astatike
- Department of Chemistry, University of Colorado Denver, Denver, CO 80217-3364, USA
| | - Christopher J. Phiel
- Department of Integrative Biology, University of Colorado Denver, CO 80217-3364, USA
| | - Tatiana G. Kutateladze
- Department of Pharmacology, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - Tao P. Wu
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - Srinivas Ramachandran
- Department of Biochemistry and Molecular Genetics, University of Colorado School of Medicine, Aurora, CO, USA
- RNA Bioscience Initiative, University of Colorado School of Medicine, Aurora, CO, USA
| | - Xiaojun Ren
- Department of Chemistry, University of Colorado Denver, Denver, CO 80217-3364, USA
- Department of Integrative Biology, University of Colorado Denver, CO 80217-3364, USA
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16
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Wang J, Chen Y, Xiao Z, Liu X, Liu C, Huang K, Chen H. Phase Separation of Chromatin Structure-related Biomolecules: A Driving Force for Epigenetic Regulations. Curr Protein Pept Sci 2024; 25:553-566. [PMID: 38551058 DOI: 10.2174/0113892037296216240301074253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2024] [Revised: 02/12/2024] [Accepted: 02/16/2024] [Indexed: 07/25/2024]
Abstract
Intracellularly, membrane-less organelles are formed by spontaneous fusion and fission of macro-molecules in a process called phase separation, which plays an essential role in cellular activities. In certain disease states, such as cancers and neurodegenerative diseases, aberrant phase separations take place and participate in disease progression. Chromatin structure-related proteins, based on their characteristics and upon external stimuli, phase separate to exert functions like genome assembly, transcription regulation, and signal transduction. Moreover, many chromatin structure-related proteins, such as histones, histone-modifying enzymes, DNA-modifying enzymes, and DNA methylation binding proteins, are involved in epigenetic regulations through phase separation. This review introduces phase separation and how phase separation affects epigenetics with a focus on chromatin structure-related molecules.
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Affiliation(s)
- Jiao Wang
- Wuhan No.1 Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430000, China
| | - Yuchen Chen
- Tongji School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Zixuan Xiao
- ISA Wenhua Wuhan High School, Fenglin Road, Junshan New Town, Wuhan Economics & Technological Development Zone, Wuhan, Hubei 430119, China
| | - Xikai Liu
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan 430072, China
| | - Chengyu Liu
- Wuhan No.1 Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430000, China
| | - Kun Huang
- Tongji School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Hong Chen
- Tongji School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
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Liu J, Fan H, Liang X, Chen Y. Polycomb repressor complex: Its function in human cancer and therapeutic target strategy. Biomed Pharmacother 2023; 169:115897. [PMID: 37981459 DOI: 10.1016/j.biopha.2023.115897] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Revised: 11/07/2023] [Accepted: 11/13/2023] [Indexed: 11/21/2023] Open
Abstract
The Polycomb Repressor Complex (PRC) plays a pivotal role in gene regulation during development and disease, with dysregulation contributing significantly to various human cancers. The intricate interplay between PRC and cellular signaling pathways sheds light on cancer complexity. PRC presents promising therapeutic opportunities, with inhibitors undergoing rigorous evaluation in preclinical and clinical studies. In this review, we emphasize the critical role of PRC complex in gene regulation, particularly PcG proteins mediated chromatin compaction through phase separation. We also highlight the pathological implications of PRC complex dysregulation in various tumors, elucidating underlying mechanisms driving cancer progression. The burgeoning field of therapeutic strategies targeting PRC complexes, notably EZH2 inhibitors, has advanced significantly. However, we explore the need for combination therapies to enhance PRC targeted treatments efficacy, providing a glimpse into the future of cancer therapeutics.
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Affiliation(s)
- Jingrong Liu
- Ganjiang Chinese Medicine Innovation Center, Nanchang 330000, China
| | - Hongjie Fan
- Ganjiang Chinese Medicine Innovation Center, Nanchang 330000, China
| | - Xinmiao Liang
- Ganjiang Chinese Medicine Innovation Center, Nanchang 330000, China; CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.
| | - Yang Chen
- Ganjiang Chinese Medicine Innovation Center, Nanchang 330000, China; CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.
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18
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Abstract
The eukaryotic nucleus displays a variety of membraneless compartments with distinct biomolecular composition and specific cellular activities. Emerging evidence indicates that protein-based liquid-liquid phase separation (LLPS) plays an essential role in the formation and dynamic regulation of heterochromatin compartmentalization. This feature is especially conspicuous at the pericentric heterochromatin domains. In this review, we will describe our understanding of heterochromatin organization and LLPS. In addition, we will highlight the increasing importance of multivalent weak homo- and heteromolecular interactions in LLPS-mediated heterochromatin compartmentalization in the complex environment inside living cells.
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Affiliation(s)
- Hui Zhang
- Cell Biology and Epigenetics, Department of Biology, Technical University of Darmstadt, Darmstadt, Germany
| | - Weihua Qin
- Human Biology and Bioimaging, Faculty of Biology, Ludwig Maximilians University Munich, Planegg-Martinsried, Germany
| | - Hector Romero
- Cell Biology and Epigenetics, Department of Biology, Technical University of Darmstadt, Darmstadt, Germany
| | - Heinrich Leonhardt
- Human Biology and Bioimaging, Faculty of Biology, Ludwig Maximilians University Munich, Planegg-Martinsried, Germany
| | - M. Cristina Cardoso
- Cell Biology and Epigenetics, Department of Biology, Technical University of Darmstadt, Darmstadt, Germany,CONTACT M. Cristina Cardoso Cell Biology and Epigenetics, Department of Biology, Technical University of Darmstadt, Schnittspahnstr. 10, 64287Darmstadt, Germany
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19
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Kozlowski P. Thirty Years with ERH: An mRNA Splicing and Mitosis Factor Only or Rather a Novel Genome Integrity Protector? Cells 2023; 12:2449. [PMID: 37887293 PMCID: PMC10605862 DOI: 10.3390/cells12202449] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Revised: 10/10/2023] [Accepted: 10/12/2023] [Indexed: 10/28/2023] Open
Abstract
ERH is a 100 to about 110 aa nuclear protein with unique primary and three-dimensional structures that are very conserved from simple eukaryotes to humans, albeit some species have lost its gene, with most higher fungi being a noteworthy example. Initially, studies on Drosophila melanogaster implied its function in pyrimidine metabolism. Subsequently, research on Xenopus laevis suggested that it acts as a transcriptional repressor. Finally, studies in humans pointed to a role in pre-mRNA splicing and in mitosis but further research, also in Caenorhabditis elegans and Schizosaccharomyces pombe, demonstrated its much broader activity, namely involvement in the biogenesis of mRNA, and miRNA, piRNA and some other ncRNAs, and in repressive heterochromatin formation. ERH interacts with numerous, mostly taxon-specific proteins, like Mmi1 and Mei2 in S. pombe, PID-3/PICS-1, TOST-1 and PID-1 in C. elegans, and DGCR8, CIZ1, PDIP46/SKAR and SAFB1/2 in humans. There are, however, some common themes in this wide range of processes and partners, such as: (a) ERH homodimerizes to form a scaffold for several complexes involved in the metabolism of nucleic acids, (b) all these RNAs are RNA polymerase II transcripts, (c) pre-mRNAs, whose splicing depends on ERH, are enriched in transcripts of DNA damage response and DNA metabolism genes, and (d) heterochromatin is formed to silence unwanted transcription, e.g., from repetitive elements. Thus, it seems that ERH has been adopted for various pathways that serve to maintain genome integrity.
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Affiliation(s)
- Piotr Kozlowski
- Department of Molecular Biology, Institute of Biochemistry, Faculty of Biology, University of Warsaw, Miecznikowa 1, 02-096 Warsaw, Poland
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20
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Patowary A, Zhang P, Jops C, Vuong CK, Ge X, Hou K, Kim M, Gong N, Margolis M, Vo D, Wang X, Liu C, Pasaniuc B, Li JJ, Gandal MJ, de la Torre-Ubieta L. Developmental isoform diversity in the human neocortex informs neuropsychiatric risk mechanisms. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.25.534016. [PMID: 36993726 PMCID: PMC10055310 DOI: 10.1101/2023.03.25.534016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
RNA splicing is highly prevalent in the brain and has strong links to neuropsychiatric disorders, yet the role of cell-type-specific splicing or transcript-isoform diversity during human brain development has not been systematically investigated. Here, we leveraged single-molecule long-read sequencing to deeply profile the full-length transcriptome of the germinal zone (GZ) and cortical plate (CP) regions of the developing human neocortex at tissue and single-cell resolution. We identified 214,516 unique isoforms, of which 72.6% are novel (unannotated in Gencode-v33), and uncovered a substantial contribution of transcript-isoform diversity, regulated by RNA binding proteins, in defining cellular identity in the developing neocortex. We leveraged this comprehensive isoform-centric gene annotation to re-prioritize thousands of rare de novo risk variants and elucidate genetic risk mechanisms for neuropsychiatric disorders. One-Sentence Summary A cell-specific atlas of gene isoform expression helps shape our understanding of brain development and disease. Structured Abstract INTRODUCTION: The development of the human brain is regulated by precise molecular and genetic mechanisms driving spatio-temporal and cell-type-specific transcript expression programs. Alternative splicing, a major mechanism increasing transcript diversity, is highly prevalent in the human brain, influences many aspects of brain development, and has strong links to neuropsychiatric disorders. Despite this, the cell-type-specific transcript-isoform diversity of the developing human brain has not been systematically investigated.RATIONALE: Understanding splicing patterns and isoform diversity across the developing neocortex has translational relevance and can elucidate genetic risk mechanisms in neurodevelopmental disorders. However, short-read sequencing, the prevalent technology for transcriptome profiling, is not well suited to capturing alternative splicing and isoform diversity. To address this, we employed third-generation long-read sequencing, which enables capture and sequencing of complete individual RNA molecules, to deeply profile the full-length transcriptome of the germinal zone (GZ) and cortical plate (CP) regions of the developing human neocortex at tissue and single-cell resolution.RESULTS: We profiled microdissected GZ and CP regions of post-conception week (PCW) 15-17 human neocortex in bulk and at single-cell resolution across six subjects using high-fidelity long-read sequencing (PacBio IsoSeq). We identified 214,516 unique isoforms, of which 72.6% were novel (unannotated in Gencode), and >7,000 novel exons, expanding the proteome by 92,422 putative proteoforms. We uncovered thousands of isoform switches during cortical neurogenesis predicted to impact RNA regulatory domains or protein structure and implicating previously uncharacterized RNA-binding proteins in cellular identity and neuropsychiatric disease. At the single-cell level, early-stage excitatory neurons exhibited the greatest isoform diversity, and isoform-centric single-cell clustering led to the identification of previously uncharacterized cell states. We systematically assessed the contribution of transcriptomic features, and localized cell and spatio-temporal transcript expression signatures across neuropsychiatric disorders, revealing predominant enrichments in dynamic isoform expression and utilization patterns and that the number and complexity of isoforms per gene is strongly predictive of disease. Leveraging this resource, we re-prioritized thousands of rare de novo risk variants associated with autism spectrum disorders (ASD), intellectual disability (ID), and neurodevelopmental disorders (NDDs), more broadly, to potentially more severe consequences and revealed a larger proportion of cryptic splice variants with the expanded transcriptome annotation provided in this study.CONCLUSION: Our study offers a comprehensive landscape of isoform diversity in the human neocortex during development. This extensive cataloging of novel isoforms and splicing events sheds light on the underlying mechanisms of neurodevelopmental disorders and presents an opportunity to explore rare genetic variants linked to these conditions. The implications of our findings extend beyond fundamental neuroscience, as they provide crucial insights into the molecular basis of developmental brain disorders and pave the way for targeted therapeutic interventions. To facilitate exploration of this dataset we developed an online portal ( https://sciso.gandallab.org/ ).
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Cherney RE, Eberhard QE, Giri G, Mills CA, Porrello A, Zhang Z, White D, Trotman JB, Herring LE, Dominguez D, Calabrese JM. SAFB associates with nascent RNAs and can promote gene expression in mouse embryonic stem cells. RNA (NEW YORK, N.Y.) 2023; 29:1535-1556. [PMID: 37468167 PMCID: PMC10578485 DOI: 10.1261/rna.079569.122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Accepted: 06/23/2023] [Indexed: 07/21/2023]
Abstract
Scaffold attachment factor B (SAFB) is a conserved RNA-binding protein that is essential for early mammalian development. However, the functions of SAFB in mouse embryonic stem cells (ESCs) have not been characterized. Using RNA immunoprecipitation followed by RNA-seq (RIP-seq), we examined the RNAs associated with SAFB in wild-type and SAFB/SAFB2 double-knockout ESCs. SAFB predominantly associated with introns of protein-coding genes through purine-rich motifs. The transcript most enriched in SAFB association was the lncRNA Malat1, which also contains a purine-rich region in its 5' end. Knockout of SAFB/SAFB2 led to differential expression of approximately 1000 genes associated with multiple biological processes, including apoptosis, cell division, and cell migration. Knockout of SAFB/SAFB2 also led to splicing changes in a set of genes that were largely distinct from those that exhibited changes in expression level. The spliced and nascent transcripts of many genes whose expression levels were positively regulated by SAFB also associated with high levels of SAFB, implying that SAFB binding promotes their expression. Reintroduction of SAFB into double-knockout cells restored gene expression toward wild-type levels, an effect again observable at the level of spliced and nascent transcripts. Proteomics analysis revealed a significant enrichment of nuclear speckle-associated and RS domain-containing proteins among SAFB interactors. Neither Xist nor Polycomb functions were dramatically altered in SAFB/2 knockout ESCs. Our findings suggest that among other potential functions in ESCs, SAFB promotes the expression of certain genes through its ability to bind nascent RNA.
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Affiliation(s)
- Rachel E Cherney
- Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
- RNA Discovery Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
- Curriculum in Genetics and Molecular Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
| | - Quinn E Eberhard
- Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
- RNA Discovery Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
- Curriculum in Bioinformatics and Computational Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
| | - Gilbert Giri
- Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
- RNA Discovery Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
- Curriculum in Bioinformatics and Computational Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
| | - Christine A Mills
- Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
- Proteomics Core Facility, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
| | - Alessandro Porrello
- RNA Discovery Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
| | - Zhiyue Zhang
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
- Department of Computer Science, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
| | - David White
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
- Department of Computer Science, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
| | - Jackson B Trotman
- Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
- RNA Discovery Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
| | - Laura E Herring
- Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
- Proteomics Core Facility, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
| | - Daniel Dominguez
- Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
- RNA Discovery Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
| | - J Mauro Calabrese
- Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
- RNA Discovery Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
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22
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Yin Y, Shen X. Noncoding RNA-chromatin association: Functions and mechanisms. FUNDAMENTAL RESEARCH 2023; 3:665-675. [PMID: 38933302 PMCID: PMC11197541 DOI: 10.1016/j.fmre.2023.03.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Revised: 03/12/2023] [Accepted: 03/23/2023] [Indexed: 06/28/2024] Open
Abstract
Pervasive transcription of the mammalian genome produces hundreds of thousands of noncoding RNAs (ncRNAs). Numerous studies have suggested that some of these ncRNAs regulate multiple cellular processes and play important roles in physiological and pathological processes. Notably, a large subset of ncRNAs is enriched on chromatin and participates in regulating gene expression and the dynamics of chromatin structure and status. In this review, we summarize recent advances in the functional study of chromatin-associated ncRNAs and mechanistic insights into how these ncRNAs associate with chromatin. We also discuss the potential future challenges which still need to be overcome in this field.
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Affiliation(s)
- Yafei Yin
- Department of Cell Biology and Department of Cardiology of the Second Affiliated Hospital, Zhejiang University School of Medicine, Yuhangtang Road, Hangzhou, Zhejiang 310058, China
| | - Xiaohua Shen
- Tsinghua-Peking Center for Life Sciences, School of Medicine and School of Life Sciences, Tsinghua University, Beijing 100084, China
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23
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Guo G, Wang X, Zhang Y, Li T. Sequence variations of phase-separating proteins and resources for studying biomolecular condensates. Acta Biochim Biophys Sin (Shanghai) 2023; 55:1119-1132. [PMID: 37464880 PMCID: PMC10423696 DOI: 10.3724/abbs.2023131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Accepted: 06/06/2023] [Indexed: 07/20/2023] Open
Abstract
Phase separation (PS) is an important mechanism underlying the formation of biomolecular condensates. Physiological condensates are associated with numerous biological processes, such as transcription, immunity, signaling, and synaptic transmission. Changes in particular amino acids or segments can disturb the protein's phase behavior and interactions with other biomolecules in condensates. It is thus presumed that variations in the phase-separating-prone domains can significantly impact the properties and functions of condensates. The dysfunction of condensates contributes to a number of pathological processes. Pharmacological perturbation of these condensates is proposed as a promising way to restore physiological states. In this review, we characterize the variations observed in PS proteins that lead to aberrant biomolecular compartmentalization. We also showcase recent advancements in bioinformatics of membraneless organelles (MLOs), focusing on available databases useful for screening PS proteins and describing endogenous condensates, guiding researchers to seek the underlying pathogenic mechanisms of biomolecular condensates.
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Affiliation(s)
- Gaigai Guo
- Department of Biomedical InformaticsSchool of Basic Medical SciencesPeking University Health Science CenterBeijing100191China
| | - Xinxin Wang
- Department of Biomedical InformaticsSchool of Basic Medical SciencesPeking University Health Science CenterBeijing100191China
| | - Yi Zhang
- Department of Biomedical InformaticsSchool of Basic Medical SciencesPeking University Health Science CenterBeijing100191China
| | - Tingting Li
- Department of Biomedical InformaticsSchool of Basic Medical SciencesPeking University Health Science CenterBeijing100191China
- Key Laboratory for NeuroscienceMinistry of Education/National Health Commission of ChinaPeking UniversityBeijing100191China
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24
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Cherney RE, Mills CA, Herring LE, Braceros AK, Calabrese JM. A monoclonal antibody raised against human EZH2 cross-reacts with the RNA-binding protein SAFB. Biol Open 2023; 12:bio059955. [PMID: 37283223 PMCID: PMC10259849 DOI: 10.1242/bio.059955] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Accepted: 05/12/2023] [Indexed: 06/08/2023] Open
Abstract
The Polycomb Repressive Complex 2 (PRC2) is a conserved enzyme that tri-methylates Lysine 27 on Histone 3 (H3K27me3) to promote gene silencing. PRC2 is remarkably responsive to the expression of certain long noncoding RNAs (lncRNAs). In the most notable example, PRC2 is recruited to the X-chromosome shortly after expression of the lncRNA Xist begins during X-chromosome inactivation. However, the mechanisms by which lncRNAs recruit PRC2 to chromatin are not yet clear. We report that a broadly used rabbit monoclonal antibody raised against human EZH2, a catalytic subunit of PRC2, cross-reacts with an RNA-binding protein called Scaffold Attachment Factor B (SAFB) in mouse embryonic stem cells (ESCs) under buffer conditions that are commonly used for chromatin immunoprecipitation (ChIP). Knockout of EZH2 in ESCs demonstrated that the antibody is specific for EZH2 by western blot (no cross-reactivity). Likewise, comparison to previously published datasets confirmed that the antibody recovers PRC2-bound sites by ChIP-Seq. However, RNA-IP from formaldehyde-crosslinked ESCs using ChIP wash conditions recovers distinct peaks of RNA association that co-localize with peaks of SAFB and whose enrichment disappears upon knockout of SAFB but not EZH2. IP and mass spectrometry-based proteomics in wild-type and EZH2 knockout ESCs confirm that the EZH2 antibody recovers SAFB in an EZH2-independent manner. Our data highlight the importance of orthogonal assays when studying interactions between chromatin-modifying enzymes and RNA.
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Affiliation(s)
- Rachel E. Cherney
- Department of Pharmacology, University of North Carolina at Chapel Hill, 120 Mason Farm Road, Chapel Hill, NC 27599, USA.
- RNA Discovery Center, University of North Carolina at Chapel Hill, 120 Mason Farm Road, Chapel Hill, NC 27599, USA.
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, 120 Mason Farm Road, Chapel Hill, NC 27599, USA.
- Curriculum in Genetics and Molecular Biology, University of North Carolina at Chapel Hill, 120 Mason Farm Road, Chapel Hill, NC 27599, USA.
| | - Christine A. Mills
- Department of Pharmacology, University of North Carolina at Chapel Hill, 120 Mason Farm Road, Chapel Hill, NC 27599, USA.
- Proteomics Core Facility, University of North Carolina at Chapel Hill, 120 Mason Farm Road, Chapel Hill, NC 27599, USA.
| | - Laura E. Herring
- Department of Pharmacology, University of North Carolina at Chapel Hill, 120 Mason Farm Road, Chapel Hill, NC 27599, USA.
- Proteomics Core Facility, University of North Carolina at Chapel Hill, 120 Mason Farm Road, Chapel Hill, NC 27599, USA.
| | - Aki K. Braceros
- Department of Pharmacology, University of North Carolina at Chapel Hill, 120 Mason Farm Road, Chapel Hill, NC 27599, USA.
- RNA Discovery Center, University of North Carolina at Chapel Hill, 120 Mason Farm Road, Chapel Hill, NC 27599, USA.
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, 120 Mason Farm Road, Chapel Hill, NC 27599, USA.
- Curriculum in Biochemistry and Biophysics, University of North Carolina at Chapel Hill, 120 Mason Farm Road, Chapel Hill, NC 27599, USA.
- Curriculum in Mechanistic, Interdisciplinary Studies of Biological Systems, University of North Carolina at Chapel Hill, 120 Mason Farm Road, Chapel Hill, NC 27599, USA.
| | - J. Mauro Calabrese
- Department of Pharmacology, University of North Carolina at Chapel Hill, 120 Mason Farm Road, Chapel Hill, NC 27599, USA.
- RNA Discovery Center, University of North Carolina at Chapel Hill, 120 Mason Farm Road, Chapel Hill, NC 27599, USA.
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, 120 Mason Farm Road, Chapel Hill, NC 27599, USA.
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25
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McCarthy RL, Zhang J, Zaret KS. Diverse heterochromatin states restricting cell identity and reprogramming. Trends Biochem Sci 2023; 48:513-526. [PMID: 36990958 PMCID: PMC10182259 DOI: 10.1016/j.tibs.2023.02.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Revised: 02/16/2023] [Accepted: 02/24/2023] [Indexed: 03/29/2023]
Abstract
Heterochromatin is defined as a chromosomal domain harboring repressive H3K9me2/3 or H3K27me3 histone modifications and relevant factors that physically compact the chromatin. Heterochromatin can restrict where transcription factors bind, providing a barrier to gene activation and changes in cell identity. While heterochromatin thus helps maintain cell differentiation, it presents a barrier to overcome during efforts to reprogram cells for biomedical purposes. Recent findings have revealed complexity in the composition and regulation of heterochromatin, and shown that transiently disrupting the machinery of heterochromatin can enhance reprogramming. Here, we discuss how heterochromatin is established and maintained during development, and how our growing understanding of the mechanisms regulating H3K9me3 heterochromatin can be leveraged to improve our ability to direct changes in cell identity.
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Affiliation(s)
- Ryan L McCarthy
- Institute for Regenerative Medicine, Penn Epigenetics Institute, Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Jingchao Zhang
- Institute for Regenerative Medicine, Penn Epigenetics Institute, Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Kenneth S Zaret
- Institute for Regenerative Medicine, Penn Epigenetics Institute, Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
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26
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Li S, Shen X. Long interspersed nuclear element 1 and B1/Alu repeats blueprint genome compartmentalization. Curr Opin Genet Dev 2023; 80:102049. [PMID: 37229928 DOI: 10.1016/j.gde.2023.102049] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Revised: 04/14/2023] [Accepted: 04/15/2023] [Indexed: 05/27/2023]
Abstract
The organization of the genome into euchromatin and heterochromatin has been known for almost 100 years [1]. More than 50% of mammalian genomes contain repetitive sequences [2,3]. Recently, a functional link between the genome and its folding has been identified [4,5]. Homotypic clustering of long interspersed nuclear element 1 (LINE1 or L1) and B1/Alu retrotransposons forms grossly exclusive nuclear domains that characterize and predict heterochromatin and euchromatin, respectively. The spatial segregation of L1 and B1/Alu-rich compartments is conserved in mammalian cells and can be rebuilt during the cell cycle and established de novo in early embryogenesis. Inhibition of L1 RNA drastically weakened homotypic repeat contacts and compartmental segregation, indicating that L1 plays a more significant role than just being a compartmental marker. This simple and inclusive genetic coding model of L1 and B1/Alu in shaping the macroscopic structure of the genome provides a plausible explanation for the remarkable conservation and robustness of its folding in mammalian cells. It also proposes a conserved core structure on which subsequent dynamic regulation takes place.
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Affiliation(s)
- Siyang Li
- Department of Basic Medical Sciences, School of Medicine, Center for Life Sciences, Tsinghua University, Beijing 100084, China
| | - Xiaohua Shen
- Department of Basic Medical Sciences, School of Medicine, Center for Life Sciences, Tsinghua University, Beijing 100084, China.
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27
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Gavrilova AA, Fefilova AS, Vishnyakov IE, Kuznetsova IM, Turoverov KK, Uversky VN, Fonin AV. On the Roles of the Nuclear Non-Coding RNA-Dependent Membrane-Less Organelles in the Cellular Stress Response. Int J Mol Sci 2023; 24:ijms24098108. [PMID: 37175815 PMCID: PMC10179167 DOI: 10.3390/ijms24098108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2023] [Revised: 04/21/2023] [Accepted: 04/25/2023] [Indexed: 05/15/2023] Open
Abstract
At the beginning of the 21st century, it became obvious that radical changes had taken place in the concept of living matter and, in particular, in the concept of the organization of intracellular space. The accumulated data testify to the essential importance of phase transitions of biopolymers (first of all, intrinsically disordered proteins and RNA) in the spatiotemporal organization of the intracellular space. Of particular interest is the stress-induced reorganization of the intracellular space. Examples of organelles formed in response to stress are nuclear A-bodies and nuclear stress bodies. The formation of these organelles is based on liquid-liquid phase separation (LLPS) of intrinsically disordered proteins (IDPs) and non-coding RNA. Despite their overlapping composition and similar mechanism of formation, these organelles have different functional activities and physical properties. In this review, we will focus our attention on these membrane-less organelles (MLOs) and describe their functions, structure, and mechanism of formation.
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Affiliation(s)
- Anastasia A Gavrilova
- Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology, Russian Academy of Sciences, 194064 St. Petersburg, Russia
| | - Anna S Fefilova
- Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology, Russian Academy of Sciences, 194064 St. Petersburg, Russia
| | - Innokentii E Vishnyakov
- Group of Molecular Cytology of Prokaryotes and Bacterial Invasion, Institute of Cytology, Russian Academy of Sciences, 194064 St. Petersburg, Russia
| | - Irina M Kuznetsova
- Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology, Russian Academy of Sciences, 194064 St. Petersburg, Russia
| | - Konstantin K Turoverov
- Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology, Russian Academy of Sciences, 194064 St. Petersburg, Russia
| | - Vladimir N Uversky
- Department of Molecular Medicine and USF Health Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA
| | - Alexander V Fonin
- Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology, Russian Academy of Sciences, 194064 St. Petersburg, Russia
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28
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Wang B, Ji L, Bian Q. SATB1 regulates 3D genome architecture in T cells by constraining chromatin interactions surrounding CTCF-binding sites. Cell Rep 2023; 42:112323. [PMID: 37000624 DOI: 10.1016/j.celrep.2023.112323] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Revised: 01/20/2023] [Accepted: 03/16/2023] [Indexed: 04/01/2023] Open
Abstract
Special AT-rich sequence binding protein 1 (SATB1) has long been proposed to act as a global chromatin loop organizer in T cells. However, the exact functions of SATB1 in spatial genome organization remain elusive. Here we show that the depletion of SATB1 in human and murine T cells leads to transcriptional dysregulation for genes involved in T cell activation, as well as alterations of 3D genome architecture at multiple levels, including compartments, topologically associating domains, and loops. Importantly, SATB1 extensively colocalizes with CTCF throughout the genome. Depletion of SATB1 leads to increased chromatin contacts among and across the SATB1/CTCF co-occupied sites, thereby affecting the transcription of critical regulators of T cell activation. The loss of SATB1 does not affect CTCF occupancy but significantly reduces the retention of CTCF in the nuclear matrix. Collectively, our data show that SATB1 contributes to 3D genome organization by constraining chromatin topology surrounding CTCF-binding sites.
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Affiliation(s)
- Bao Wang
- Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200125, China; Shanghai Institute of Precision Medicine, Shanghai 200125, China
| | - Luzhang Ji
- Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200125, China; Shanghai Institute of Precision Medicine, Shanghai 200125, China
| | - Qian Bian
- Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200125, China; Shanghai Institute of Precision Medicine, Shanghai 200125, China; Shanghai Key Laboratory of Reproductive Medicine, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China.
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29
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Liu Y, Huang Z, Liu H, Ji Z, Arora A, Cai D, Wang H, Liu M, Simko EAJ, Zhang Y, Periz G, Liu Z, Wang J. DNA-initiated epigenetic cascades driven by C9orf72 hexanucleotide repeat. Neuron 2023; 111:1205-1221.e9. [PMID: 36822200 PMCID: PMC10121948 DOI: 10.1016/j.neuron.2023.01.022] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Revised: 12/08/2022] [Accepted: 01/27/2023] [Indexed: 02/24/2023]
Abstract
The C9orf72 hexanucleotide repeat expansion (HRE) is the most frequent genetic cause of the neurodegenerative diseases amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Here, we describe the pathogenic cascades that are initiated by the C9orf72 HRE DNA. The HRE DNA binds to its protein partner DAXX and promotes its liquid-liquid phase separation, which is capable of reorganizing genomic structures. An HRE-dependent nuclear accumulation of DAXX drives chromatin remodeling and epigenetic changes such as histone hypermethylation and hypoacetylation in patient cells. While regulating global gene expression, DAXX plays a key role in the suppression of basal and stress-inducible expression of C9orf72 via chromatin remodeling and epigenetic modifications of the promoter of the major C9orf72 transcript. Downregulation of DAXX or rebalancing the epigenetic modifications mitigates the stress-induced sensitivity of C9orf72-patient-derived motor neurons. These studies reveal a C9orf72 HRE DNA-dependent regulatory mechanism for both local and genomic architectural changes in the relevant diseases.
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Affiliation(s)
- Yang Liu
- Department of Biochemistry and Molecular Biology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21205, USA; Department of Neuroscience, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Zhiyuan Huang
- Department of Biochemistry and Molecular Biology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21205, USA; Department of Neuroscience, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Honghe Liu
- Department of Biochemistry and Molecular Biology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21205, USA; Department of Neuroscience, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Zhicheng Ji
- Department of Biostatistics and Bioinformatics, Duke University School of Medicine, Duke University, Durham, NC 27710, USA
| | - Amit Arora
- Department of Biochemistry and Molecular Biology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21205, USA; Department of Neuroscience, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Danfeng Cai
- Department of Biochemistry and Molecular Biology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21205, USA; Department of Oncology, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA; Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA; Department of Biophysics and Biophysical Chemistry, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Hongjin Wang
- Department of Biochemistry and Molecular Biology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21205, USA; Department of Neuroscience, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Mingming Liu
- Department of Biochemistry and Molecular Biology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21205, USA; Department of Neuroscience, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Eric A J Simko
- Department of Biochemistry and Molecular Biology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21205, USA; Department of Neuroscience, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Yanjun Zhang
- Department of Biochemistry and Molecular Biology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21205, USA; Department of Neuroscience, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Goran Periz
- Department of Biochemistry and Molecular Biology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21205, USA; Department of Neuroscience, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Zhe Liu
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Jiou Wang
- Department of Biochemistry and Molecular Biology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21205, USA; Department of Neuroscience, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA.
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30
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Deshpande AJ, Zhu N. Silencing with SAFB: a new role for HOXA9 in AML. Blood 2023; 141:1653-1655. [PMID: 37022737 PMCID: PMC10113172 DOI: 10.1182/blood.2022019244] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/07/2023] Open
Affiliation(s)
| | - Nan Zhu
- Versiti Blood Research Institute
- Medical College of Wisconsin
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31
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Agrawal-Singh S, Bagri J, Giotopoulos G, Azazi DMA, Horton SJ, Lopez CK, Anand S, Bach AS, Stedham F, Antrobus R, Houghton JW, Vassiliou GS, Sasca D, Yun H, Whetton AD, Huntly BJP. HOXA9 forms a repressive complex with nuclear matrix-associated protein SAFB to maintain acute myeloid leukemia. Blood 2023; 141:1737-1754. [PMID: 36577137 PMCID: PMC10113176 DOI: 10.1182/blood.2022016528] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Revised: 11/07/2022] [Accepted: 11/28/2022] [Indexed: 12/29/2022] Open
Abstract
HOXA9 is commonly upregulated in acute myeloid leukemia (AML), in which it confers a poor prognosis. Characterizing the protein interactome of endogenous HOXA9 in human AML, we identified a chromatin complex of HOXA9 with the nuclear matrix attachment protein SAFB. SAFB perturbation phenocopied HOXA9 knockout to decrease AML proliferation, increase differentiation and apoptosis in vitro, and prolong survival in vivo. Integrated genomic, transcriptomic, and proteomic analyses further demonstrated that the HOXA9-SAFB (H9SB)-chromatin complex associates with nucleosome remodeling and histone deacetylase (NuRD) and HP1γ to repress the expression of factors associated with differentiation and apoptosis, including NOTCH1, CEBPδ, S100A8, and CDKN1A. Chemical or genetic perturbation of NuRD and HP1γ-associated catalytic activity also triggered differentiation, apoptosis, and the induction of these tumor-suppressive genes. Importantly, this mechanism is operative in other HOXA9-dependent AML genotypes. This mechanistic insight demonstrates the active HOXA9-dependent differentiation block as a potent mechanism of disease maintenance in AML that may be amenable to therapeutic intervention by targeting the H9SB interface and/or NuRD and HP1γ activity.
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Affiliation(s)
- Shuchi Agrawal-Singh
- Wellcome Trust-MRC Cambridge Stem Cell Institute, Cambridge, United Kingdom
- Department of Haematology, University of Cambridge, Cambridge, United Kingdom
| | - Jaana Bagri
- Wellcome Trust-MRC Cambridge Stem Cell Institute, Cambridge, United Kingdom
- Department of Haematology, University of Cambridge, Cambridge, United Kingdom
| | - George Giotopoulos
- Wellcome Trust-MRC Cambridge Stem Cell Institute, Cambridge, United Kingdom
- Department of Haematology, University of Cambridge, Cambridge, United Kingdom
| | - Dhoyazan M A Azazi
- Wellcome Trust-MRC Cambridge Stem Cell Institute, Cambridge, United Kingdom
- Department of Haematology, University of Cambridge, Cambridge, United Kingdom
| | - Sarah J Horton
- Wellcome Trust-MRC Cambridge Stem Cell Institute, Cambridge, United Kingdom
- Department of Haematology, University of Cambridge, Cambridge, United Kingdom
| | - Cecile K Lopez
- Wellcome Trust-MRC Cambridge Stem Cell Institute, Cambridge, United Kingdom
- Department of Haematology, University of Cambridge, Cambridge, United Kingdom
| | - Shubha Anand
- Cancer Molecular Diagnostics Laboratory, Cancer Research UK Cambridge Centre, Cambridge, United Kingdom
| | - Anne-Sophie Bach
- Wellcome Trust-MRC Cambridge Stem Cell Institute, Cambridge, United Kingdom
- Department of Haematology, University of Cambridge, Cambridge, United Kingdom
| | - Frances Stedham
- Wellcome Trust-MRC Cambridge Stem Cell Institute, Cambridge, United Kingdom
- Department of Haematology, University of Cambridge, Cambridge, United Kingdom
| | - Robin Antrobus
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, United Kingdom
| | - Jack W Houghton
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, United Kingdom
| | - George S Vassiliou
- Wellcome Trust-MRC Cambridge Stem Cell Institute, Cambridge, United Kingdom
- Department of Haematology, University of Cambridge, Cambridge, United Kingdom
- Cambridge University Hospitals NHS Foundation Trust, Cambridge, United Kingdom
| | - Daniel Sasca
- Department of Hematology, Oncology and Pneumology, University Medical Center Mainz, Mainz, Germany
| | - Haiyang Yun
- Department of Medicine V, Hematology, Oncology and Rheumatology, University of Heidelberg, Heidelberg, Germany
| | - Anthony D Whetton
- School of Veterinary Medicine, School of Biosciences and Medicine, University of Surrey, Guildford, Surrey, United Kingdom
| | - Brian J P Huntly
- Wellcome Trust-MRC Cambridge Stem Cell Institute, Cambridge, United Kingdom
- Department of Haematology, University of Cambridge, Cambridge, United Kingdom
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, United Kingdom
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32
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Porter H, Li Y, Neguembor MV, Beltran M, Varsally W, Martin L, Cornejo MT, Pezić D, Bhamra A, Surinova S, Jenner RG, Cosma MP, Hadjur S. Cohesin-independent STAG proteins interact with RNA and R-loops and promote complex loading. eLife 2023; 12:e79386. [PMID: 37010886 PMCID: PMC10238091 DOI: 10.7554/elife.79386] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2022] [Accepted: 04/02/2023] [Indexed: 04/04/2023] Open
Abstract
Most studies of cohesin function consider the Stromalin Antigen (STAG/SA) proteins as core complex members given their ubiquitous interaction with the cohesin ring. Here, we provide functional data to support the notion that the SA subunit is not a mere passenger in this structure, but instead plays a key role in the localization of cohesin to diverse biological processes and promotes loading of the complex at these sites. We show that in cells acutely depleted for RAD21, SA proteins remain bound to chromatin, cluster in 3D and interact with CTCF, as well as with a wide range of RNA binding proteins involved in multiple RNA processing mechanisms. Accordingly, SA proteins interact with RNA, and R-loops, even in the absence of cohesin. Our results place SA1 on chromatin upstream of the cohesin ring and reveal a role for SA1 in cohesin loading which is independent of NIPBL, the canonical cohesin loader. We propose that SA1 takes advantage of structural R-loop platforms to link cohesin loading and chromatin structure with diverse functions. Since SA proteins are pan-cancer targets, and R-loops play an increasingly prevalent role in cancer biology, our results have important implications for the mechanistic understanding of SA proteins in cancer and disease.
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Affiliation(s)
- Hayley Porter
- Research Department of Cancer Biology, Cancer Institute, University College London, London, United Kingdom
| | - Yang Li
- Research Department of Cancer Biology, Cancer Institute, University College London, London, United Kingdom
| | - Maria Victoria Neguembor
- Centre for Genomic Regulation (CRG), Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Manuel Beltran
- Regulatory Genomics Group, Cancer Institute, University College London, London, United Kingdom
| | - Wazeer Varsally
- Research Department of Cancer Biology, Cancer Institute, University College London, London, United Kingdom
| | - Laura Martin
- Centre for Genomic Regulation (CRG), Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Manuel Tavares Cornejo
- Regulatory Genomics Group, Cancer Institute, University College London, London, United Kingdom
| | - Dubravka Pezić
- Research Department of Cancer Biology, Cancer Institute, University College London, London, United Kingdom
| | - Amandeep Bhamra
- Proteomics Research Translational Technology Platform, Cancer Institute, University College London, London, United Kingdom
| | - Silvia Surinova
- Proteomics Research Translational Technology Platform, Cancer Institute, University College London, London, United Kingdom
| | - Richard G Jenner
- Regulatory Genomics Group, Cancer Institute, University College London, London, United Kingdom
| | - Maria Pia Cosma
- Centre for Genomic Regulation (CRG), Barcelona Institute of Science and Technology, Barcelona, Spain
- Universitat Pompeu Fabra (UPF), Barcelona, Spain
- Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Spain
| | - Suzana Hadjur
- Research Department of Cancer Biology, Cancer Institute, University College London, London, United Kingdom
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33
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Cherney RE, Mills CA, Herring LE, Braceros AK, Calabrese JM. A monoclonal antibody raised against human EZH2 cross-reacts with the RNA-binding protein SAFB. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.04.03.535391. [PMID: 37066147 PMCID: PMC10103960 DOI: 10.1101/2023.04.03.535391] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
The Polycomb Repressive Complex 2 (PRC2) is a conserved enzyme that tri-methylates Lysine 27 on Histone 3 (H3K27me3) to promote gene silencing. PRC2 is remarkably responsive to the expression of certain long noncoding RNAs (lncRNAs). In the most notable example, PRC2 is recruited to the X-chromosome shortly after expression of the lncRNA Xist begins during X-chromosome inactivation. However, the mechanisms by which lncRNAs recruit PRC2 to chromatin are not yet clear. We report that a broadly used rabbit monoclonal antibody raised against human EZH2, a catalytic subunit of PRC2, cross-reacts with an RNA-binding protein called Scaffold Attachment Factor B (SAFB) in mouse embryonic stem cells (ESCs) under buffer conditions that are commonly used for chromatin immunoprecipitation (ChIP). Knockout of EZH2 in ESCs demonstrated that the antibody is specific for EZH2 by western blot (no cross-reactivity). Likewise, comparison to previously published datasets confirmed that the antibody recovers PRC2-bound sites by ChIP-Seq. However, RNA-IP from formaldehyde-crosslinked ESCs using ChIP wash conditions recovers distinct peaks of RNA association that co-localize with peaks of SAFB and whose enrichment disappears upon knockout of SAFB but not EZH2. IP and mass spectrometry-based proteomics in wild-type and EZH2 knockout ESCs confirm that the EZH2 antibody recovers SAFB in an EZH2-independent manner. Our data highlight the importance of orthogonal assays when studying interactions between chromatin-modifying enzymes and RNA.
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Guthmann M, Qian C, Gialdini I, Nakatani T, Ettinger A, Schauer T, Kukhtevich I, Schneider R, Lamb DC, Burton A, Torres-Padilla ME. A change in biophysical properties accompanies heterochromatin formation in mouse embryos. Genes Dev 2023; 37:336-350. [PMID: 37072228 PMCID: PMC10153458 DOI: 10.1101/gad.350353.122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Accepted: 03/31/2023] [Indexed: 04/20/2023]
Abstract
The majority of our genome is composed of repeated DNA sequences that assemble into heterochromatin, a highly compacted structure that constrains their mutational potential. How heterochromatin forms during development and how its structure is maintained are not fully understood. Here, we show that mouse heterochromatin phase-separates after fertilization, during the earliest stages of mammalian embryogenesis. Using high-resolution quantitative imaging and molecular biology approaches, we show that pericentromeric heterochromatin displays properties consistent with a liquid-like state at the two-cell stage, which change at the four-cell stage, when chromocenters mature and heterochromatin becomes silent. Disrupting the condensates results in altered transcript levels of pericentromeric heterochromatin, suggesting a functional role for phase separation in heterochromatin function. Thus, our work shows that mouse heterochromatin forms membrane-less compartments with biophysical properties that change during development and provides new insights into the self-organization of chromatin domains during mammalian embryogenesis.
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Affiliation(s)
- Manuel Guthmann
- Institute of Epigenetics and Stem Cells (IES), Helmholtz Zentrum München, D-81377 München, Germany
| | - Chen Qian
- Department of Chemistry, Center for NanoScience (CeNS), Ludwig Maximilians-Universität München, 81377 München, Germany
| | - Irene Gialdini
- Department of Chemistry, Center for NanoScience (CeNS), Ludwig Maximilians-Universität München, 81377 München, Germany
| | - Tsunetoshi Nakatani
- Institute of Epigenetics and Stem Cells (IES), Helmholtz Zentrum München, D-81377 München, Germany
| | - Andreas Ettinger
- Institute of Epigenetics and Stem Cells (IES), Helmholtz Zentrum München, D-81377 München, Germany
| | - Tamas Schauer
- Institute of Epigenetics and Stem Cells (IES), Helmholtz Zentrum München, D-81377 München, Germany
| | - Igor Kukhtevich
- Institute of Functional Epigenetics (IFE), Helmholtz Zentrum München, D-85764 Neuherberg, Germany
| | - Robert Schneider
- Institute of Functional Epigenetics (IFE), Helmholtz Zentrum München, D-85764 Neuherberg, Germany
| | - Don C Lamb
- Department of Chemistry, Center for NanoScience (CeNS), Ludwig Maximilians-Universität München, 81377 München, Germany
| | - Adam Burton
- Institute of Epigenetics and Stem Cells (IES), Helmholtz Zentrum München, D-81377 München, Germany
| | - Maria-Elena Torres-Padilla
- Institute of Epigenetics and Stem Cells (IES), Helmholtz Zentrum München, D-81377 München, Germany;
- Faculty of Biology, Ludwig-Maximilians Universität, München, 82152 Planegg, Germany
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35
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Yeo SJ, Ying C, Fullwood MJ, Tergaonkar V. Emerging regulatory mechanisms of noncoding RNAs in topologically associating domains. Trends Genet 2023; 39:217-232. [PMID: 36642680 DOI: 10.1016/j.tig.2022.12.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Revised: 12/17/2022] [Accepted: 12/20/2022] [Indexed: 01/15/2023]
Abstract
Topologically associating domains (TADs) are integral to spatial genome organization, instructing gene expression, and cell fate. Recently, several advances have uncovered roles for noncoding RNAs (ncRNAs) in the regulation of the form and function of mammalian TADs. Phase separation has also emerged as a potential arbiter of ncRNAs in the regulation of TADs. In this review we discuss the implications of these novel findings in relation to how ncRNAs might structurally and functionally regulate TADs from two perspectives: moderating loop extrusion through interactions with architectural proteins, and facilitating TAD phase separation. Additionally, we propose future studies and directions to investigate these phenomena.
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Affiliation(s)
- Samuel Jianjie Yeo
- Laboratory of NFκB Signaling, Institute of Molecular Biology (IMCB), A*STAR (Agency for Science, Technology and Research), Singapore 138673, Singapore; Lee Kong Chian School of Medicine, Nanyang Technological University (NTU), Singapore 308232, Singapore
| | - Chen Ying
- Laboratory of NFκB Signaling, Institute of Molecular Biology (IMCB), A*STAR (Agency for Science, Technology and Research), Singapore 138673, Singapore
| | - Melissa Jane Fullwood
- Cancer Science Institute of Singapore, Centre for Translational Medicine, National University of Singapore, Singapore 117599, Singapore; School of Biological Sciences, Nanyang Technological University, Singapore 637551, Singapore.
| | - Vinay Tergaonkar
- Laboratory of NFκB Signaling, Institute of Molecular Biology (IMCB), A*STAR (Agency for Science, Technology and Research), Singapore 138673, Singapore; Department of Pathology and the Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore (NUS), Singapore 117597, Singapore.
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36
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Zhu J, Chen K, Sun YH, Ye W, Liu J, Zhang D, Su N, Wu L, Kou X, Zhao Y, Wang H, Gao S, Kang L. LSM1-mediated Major Satellite RNA decay is required for nonequilibrium histone H3.3 incorporation into parental pronuclei. Nat Commun 2023; 14:957. [PMID: 36810573 PMCID: PMC9944933 DOI: 10.1038/s41467-023-36584-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Accepted: 02/06/2023] [Indexed: 02/24/2023] Open
Abstract
Epigenetic reprogramming of the parental genome is essential for zygotic genome activation and subsequent embryo development in mammals. Asymmetric incorporation of histone H3 variants into the parental genome has been observed previously, but the underlying mechanism remains elusive. In this study, we discover that RNA-binding protein LSM1-mediated major satellite RNA decay plays a central role in the preferential incorporation of histone variant H3.3 into the male pronucleus. Knockdown of Lsm1 disrupts nonequilibrium pronucleus histone incorporation and asymmetric H3K9me3 modification. Subsequently, we find that LSM1 mainly targets major satellite repeat RNA (MajSat RNA) for decay and that accumulated MajSat RNA in Lsm1-depleted oocytes leads to abnormal incorporation of H3.1 into the male pronucleus. Knockdown of MajSat RNA reverses the anomalous histone incorporation and modifications in Lsm1-knockdown zygotes. Our study therefore reveals that accurate histone variant incorporation and incidental modifications in parental pronuclei are specified by LSM1-dependent pericentromeric RNA decay.
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Affiliation(s)
- Jiang Zhu
- Institute for Regenerative Medicine, Shanghai East Hospital, Shanghai Key Laboratory of Signaling and Disease Research, School of Life Sciences and Technology, Tongji University, 200120, Shanghai, China.,Frontier Science Center for Stem Cell Research, Tongji University, 200092, Shanghai, China
| | - Kang Chen
- Institute for Regenerative Medicine, Shanghai East Hospital, Shanghai Key Laboratory of Signaling and Disease Research, School of Life Sciences and Technology, Tongji University, 200120, Shanghai, China.,Institute of Biophysics, Chinese Academy of Sciences, 100101, Beijing, China.,University of Chinese Academy of Sciences, 100049, Beijing, China
| | - Yu H Sun
- Departments of Biology, University of Rochester, 14642, Rochester, NY, USA
| | - Wen Ye
- Institute for Regenerative Medicine, Shanghai East Hospital, Shanghai Key Laboratory of Signaling and Disease Research, School of Life Sciences and Technology, Tongji University, 200120, Shanghai, China
| | - Juntao Liu
- Institute for Regenerative Medicine, Shanghai East Hospital, Shanghai Key Laboratory of Signaling and Disease Research, School of Life Sciences and Technology, Tongji University, 200120, Shanghai, China
| | - Dandan Zhang
- Institute for Regenerative Medicine, Shanghai East Hospital, Shanghai Key Laboratory of Signaling and Disease Research, School of Life Sciences and Technology, Tongji University, 200120, Shanghai, China
| | - Nan Su
- Institute for Regenerative Medicine, Shanghai East Hospital, Shanghai Key Laboratory of Signaling and Disease Research, School of Life Sciences and Technology, Tongji University, 200120, Shanghai, China
| | - Li Wu
- Clinical and Translation Research Center of Shanghai First Maternity & Infant Hospital, School of Life Sciences and Technology, Tongji University, 200092, Shanghai, China
| | - Xiaochen Kou
- Frontier Science Center for Stem Cell Research, Tongji University, 200092, Shanghai, China
| | - Yanhong Zhao
- Frontier Science Center for Stem Cell Research, Tongji University, 200092, Shanghai, China
| | - Hong Wang
- Clinical and Translation Research Center of Shanghai First Maternity & Infant Hospital, School of Life Sciences and Technology, Tongji University, 200092, Shanghai, China
| | - Shaorong Gao
- Institute for Regenerative Medicine, Shanghai East Hospital, Shanghai Key Laboratory of Signaling and Disease Research, School of Life Sciences and Technology, Tongji University, 200120, Shanghai, China. .,Frontier Science Center for Stem Cell Research, Tongji University, 200092, Shanghai, China. .,Clinical and Translation Research Center of Shanghai First Maternity & Infant Hospital, School of Life Sciences and Technology, Tongji University, 200092, Shanghai, China.
| | - Lan Kang
- Institute for Regenerative Medicine, Shanghai East Hospital, Shanghai Key Laboratory of Signaling and Disease Research, School of Life Sciences and Technology, Tongji University, 200120, Shanghai, China. .,Frontier Science Center for Stem Cell Research, Tongji University, 200092, Shanghai, China.
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37
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Korn SM, Von Ehr J, Dhamotharan K, Tants JN, Abele R, Schlundt A. Insight into the Structural Basis for Dual Nucleic Acid-Recognition by the Scaffold Attachment Factor B2 Protein. Int J Mol Sci 2023; 24:ijms24043286. [PMID: 36834708 PMCID: PMC9958909 DOI: 10.3390/ijms24043286] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2022] [Revised: 01/30/2023] [Accepted: 02/03/2023] [Indexed: 02/10/2023] Open
Abstract
The family of scaffold attachment factor B (SAFB) proteins comprises three members and was first identified as binders of the nuclear matrix/scaffold. Over the past two decades, SAFBs were shown to act in DNA repair, mRNA/(l)ncRNA processing and as part of protein complexes with chromatin-modifying enzymes. SAFB proteins are approximately 100 kDa-sized dual nucleic acid-binding proteins with dedicated domains in an otherwise largely unstructured context, but whether and how they discriminate DNA and RNA binding has remained enigmatic. We here provide the SAFB2 DNA- and RNA-binding SAP and RRM domains in their functional boundaries and use solution NMR spectroscopy to ascribe DNA- and RNA-binding functions. We give insight into their target nucleic acid preferences and map the interfaces with respective nucleic acids on sparse data-derived SAP and RRM domain structures. Further, we provide evidence that the SAP domain exhibits intra-domain dynamics and a potential tendency to dimerize, which may expand its specifically targeted DNA sequence range. Our data provide a first molecular basis of and a starting point towards deciphering DNA- and RNA-binding functions of SAFB2 on the molecular level and serve a basis for understanding its localization to specific regions of chromatin and its involvement in the processing of specific RNA species.
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Affiliation(s)
- Sophie M. Korn
- Institute for Molecular Biosciences, Biomolecular Resonance Center (BMRZ), Goethe University Frankfurt, Max-von-Laue-Str. 7-9, 60438 Frankfurt, Germany
| | - Julian Von Ehr
- Institute for Molecular Biosciences, Biomolecular Resonance Center (BMRZ), Goethe University Frankfurt, Max-von-Laue-Str. 7-9, 60438 Frankfurt, Germany
- IMPRS on Cellular Biophysics, Max-von-Laue-Str. 7-9, 60438 Frankfurt, Germany
| | - Karthikeyan Dhamotharan
- Institute for Molecular Biosciences, Biomolecular Resonance Center (BMRZ), Goethe University Frankfurt, Max-von-Laue-Str. 7-9, 60438 Frankfurt, Germany
| | - Jan-Niklas Tants
- Institute for Molecular Biosciences, Biomolecular Resonance Center (BMRZ), Goethe University Frankfurt, Max-von-Laue-Str. 7-9, 60438 Frankfurt, Germany
| | - Rupert Abele
- Institute for Biochemistry, Goethe University Frankfurt, Max-von-Laue-Str. 9, 60438 Frankfurt, Germany
| | - Andreas Schlundt
- Institute for Molecular Biosciences, Biomolecular Resonance Center (BMRZ), Goethe University Frankfurt, Max-von-Laue-Str. 7-9, 60438 Frankfurt, Germany
- Correspondence:
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38
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Soujanya M, Bihani A, Hajirnis N, Pathak RU, Mishra RK. Nuclear architecture and the structural basis of mitotic memory. CHROMOSOME RESEARCH : AN INTERNATIONAL JOURNAL ON THE MOLECULAR, SUPRAMOLECULAR AND EVOLUTIONARY ASPECTS OF CHROMOSOME BIOLOGY 2023; 31:8. [PMID: 36725757 DOI: 10.1007/s10577-023-09714-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Revised: 11/13/2022] [Accepted: 12/19/2022] [Indexed: 02/03/2023]
Abstract
The nucleus is a complex organelle that hosts the genome and is essential for vital processes like DNA replication, DNA repair, transcription, and splicing. The genome is non-randomly organized in the three-dimensional space of the nucleus. This functional sub-compartmentalization was thought to be organized on the framework of nuclear matrix (NuMat), a non-chromatin scaffold that functions as a substratum for various molecular processes of the nucleus. More recently, nuclear bodies or membrane-less subcompartments of the nucleus are thought to arise due to phase separation of chromatin, RNA, and proteins. The nuclear architecture is an amalgamation of the relative organization of chromatin, epigenetic landscape, the nuclear bodies, and the nucleoskeleton in the three-dimensional space of the nucleus. During mitosis, the nucleus undergoes drastic changes in morphology to the degree that it ceases to exist as such; various nuclear components, including the envelope that defines the nucleus, disintegrate, and the chromatin acquires mitosis-specific epigenetic marks and condenses to form chromosome. Upon mitotic exit, chromosomes are decondensed, re-establish hierarchical genome organization, and regain epigenetic and transcriptional status similar to that of the mother cell. How this mitotic memory is inherited during cell division remains a puzzle. NuMat components that are a part of the mitotic chromosome in the form of mitotic chromosome scaffold (MiCS) could potentially be the seeds that guide the relative re-establishment of the epigenome, chromosome territories, and the nuclear bodies. Here, we synthesize the advances towards understanding cellular memory of nuclear architecture across mitosis and propose a hypothesis that a subset of NuMat proteome essential for nucleation of various nuclear bodies are retained in MiCS to serve as seeds of mitotic memory, thus ensuring the daughter cells re-establish the complex status of nuclear architecture similar to that of the mother cells, thereby maintaining the pre-mitotic transcriptional status.
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Affiliation(s)
- Mamilla Soujanya
- CSIR - Centre for Cellular & Molecular Biology, Hyderabad, India
- AcSIR - Academy of Scientific and Innovative Research, Ghaziabad, India
| | - Ashish Bihani
- CSIR - Centre for Cellular & Molecular Biology, Hyderabad, India
| | - Nikhil Hajirnis
- CSIR - Centre for Cellular & Molecular Biology, Hyderabad, India
- Department of Anatomy and Neurobiology, University of Maryland, Baltimore, USA
| | - Rashmi U Pathak
- CSIR - Centre for Cellular & Molecular Biology, Hyderabad, India
| | - Rakesh K Mishra
- CSIR - Centre for Cellular & Molecular Biology, Hyderabad, India.
- AcSIR - Academy of Scientific and Innovative Research, Ghaziabad, India.
- TIGS - Tata Institute for Genetics and Society, Bangalore, India.
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39
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Mansisidor AR, Risca VI. Chromatin accessibility: methods, mechanisms, and biological insights. Nucleus 2022; 13:236-276. [PMID: 36404679 PMCID: PMC9683059 DOI: 10.1080/19491034.2022.2143106] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 10/23/2022] [Accepted: 10/30/2022] [Indexed: 11/22/2022] Open
Abstract
Access to DNA is a prerequisite to the execution of essential cellular processes that include transcription, replication, chromosomal segregation, and DNA repair. How the proteins that regulate these processes function in the context of chromatin and its dynamic architectures is an intensive field of study. Over the past decade, genome-wide assays and new imaging approaches have enabled a greater understanding of how access to the genome is regulated by nucleosomes and associated proteins. Additional mechanisms that may control DNA accessibility in vivo include chromatin compaction and phase separation - processes that are beginning to be understood. Here, we review the ongoing development of accessibility measurements, we summarize the different molecular and structural mechanisms that shape the accessibility landscape, and we detail the many important biological functions that are linked to chromatin accessibility.
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Affiliation(s)
- Andrés R. Mansisidor
- Laboratory of Genome Architecture and Dynamics, The Rockefeller University, New York, NY
| | - Viviana I. Risca
- Laboratory of Genome Architecture and Dynamics, The Rockefeller University, New York, NY
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40
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Taze C, Drakouli S, Samiotaki M, Panayotou G, Simos G, Georgatsou E, Mylonis I. Short-term hypoxia triggers ROS and SAFB mediated nuclear matrix and mRNA splicing remodeling. Redox Biol 2022; 58:102545. [PMID: 36427398 PMCID: PMC9692040 DOI: 10.1016/j.redox.2022.102545] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2022] [Accepted: 11/16/2022] [Indexed: 11/18/2022] Open
Abstract
The cellular response to hypoxia, in addition to HIF-dependent transcriptional reprogramming, also involves less characterized transcription-independent processes, such as alternative splicing of the VEGFA transcript leading to the production of the proangiogenic VEGF form. We now show that this event depends on reorganization of the splicing machinery, triggered after short-term hypoxia by ROS production and intranuclear redistribution of the nucleoskeletal proteins SAFB1/2. Exposure to low oxygen causes fast dissociation of SAFB1/2 from the nuclear matrix, which is reversible, inhibited by antioxidant treatment, and also observed under normoxia when the mitochondrial electron transport chain is blocked. This is accompanied by altered interactions between SAFB1/2 and the splicing machinery, translocation of kinase SRPK1 to the cytoplasm, and dephosphorylation of RS-splicing factors. Depletion of SAFB1/2 under normoxia phenocopies the hypoxic and ROS-mediated switch in VEGF mRNA splicing. These data suggest that ROS-dependent remodeling of the nuclear architecture can promote production of splicing variants that facilitate adaptation to hypoxia.
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Affiliation(s)
- Chrysa Taze
- Laboratory of Biochemistry, Faculty of Medicine, University of Thessaly, Biopolis, Larissa, 41500, Greece
| | - Sotiria Drakouli
- Laboratory of Biochemistry, Faculty of Medicine, University of Thessaly, Biopolis, Larissa, 41500, Greece
| | - Martina Samiotaki
- Institute for Bioinnovation, BSRC “Alexander Fleming”, Vari, 16672, Greece
| | - George Panayotou
- Institute for Bioinnovation, BSRC “Alexander Fleming”, Vari, 16672, Greece
| | - George Simos
- Laboratory of Biochemistry, Faculty of Medicine, University of Thessaly, Biopolis, Larissa, 41500, Greece,Gerald Bronfman Department of Oncology, Faculty of Medicine, McGill University, Montreal, H4A 3T2, Canada
| | - Eleni Georgatsou
- Laboratory of Biochemistry, Faculty of Medicine, University of Thessaly, Biopolis, Larissa, 41500, Greece
| | - Ilias Mylonis
- Laboratory of Biochemistry, Faculty of Medicine, University of Thessaly, Biopolis, Larissa, 41500, Greece,Corresponding author.
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41
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Wu T, Gu H, Luo Y, Wang L, Sang Q. Meiotic defects in human oocytes: Potential causes and clinical implications. Bioessays 2022; 44:e2200135. [PMID: 36207289 DOI: 10.1002/bies.202200135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Revised: 09/14/2022] [Accepted: 09/16/2022] [Indexed: 11/09/2022]
Abstract
Meiotic defects cause abnormal chromosome segregation leading to aneuploidy in mammalian oocytes. Chromosome segregation is particularly error-prone in human oocytes, but the mechanisms behind such errors remain unclear. To explain the frequent chromosome segregation errors, recent investigations have identified multiple meiotic defects and explained how these defects occur in female meiosis. In particular, we review the causes of cohesin exhaustion, leaky spindle assembly checkpoint (SAC), inherently unstable meiotic spindle, fragmented kinetochores or centromeres, abnormal aurora kinases (AURK), and clinical genetic variants in human oocytes. We mainly focus on meiotic defects in human oocytes, but also refer to the potential defects of female meiosis in mouse models.
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Affiliation(s)
- Tianyu Wu
- Institute of Pediatrics, Children's Hospital of Fudan University and Institutes of Biomedical Sciences, the State Key Laboratory of Genetic Engineering, Fudan University, Shanghai, China
| | - Hao Gu
- Institute of Pediatrics, Children's Hospital of Fudan University and Institutes of Biomedical Sciences, the State Key Laboratory of Genetic Engineering, Fudan University, Shanghai, China
| | - Yuxi Luo
- Institute of Pediatrics, Children's Hospital of Fudan University and Institutes of Biomedical Sciences, the State Key Laboratory of Genetic Engineering, Fudan University, Shanghai, China
| | - Lei Wang
- Institute of Pediatrics, Children's Hospital of Fudan University and Institutes of Biomedical Sciences, the State Key Laboratory of Genetic Engineering, Fudan University, Shanghai, China
| | - Qing Sang
- Institute of Pediatrics, Children's Hospital of Fudan University and Institutes of Biomedical Sciences, the State Key Laboratory of Genetic Engineering, Fudan University, Shanghai, China
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42
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Somasundaram K, Gupta B, Jain N, Jana S. LncRNAs divide and rule: The master regulators of phase separation. Front Genet 2022; 13:930792. [PMID: 36035193 PMCID: PMC9399341 DOI: 10.3389/fgene.2022.930792] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Accepted: 07/07/2022] [Indexed: 11/13/2022] Open
Abstract
Most of the human genome, except for a small region that transcribes protein-coding RNAs, was considered junk. With the advent of RNA sequencing technology, we know that much of the genome codes for RNAs with no protein-coding potential. Long non-coding RNAs (lncRNAs) that form a significant proportion are dynamically expressed and play diverse roles in physiological and pathological processes. Precise spatiotemporal control of their expression is essential to carry out various biochemical reactions inside the cell. Intracellular organelles with membrane-bound compartments are known for creating an independent internal environment for carrying out specific functions. The formation of membrane-free ribonucleoprotein condensates resulting in intracellular compartments is documented in recent times to execute specialized tasks such as DNA replication and repair, chromatin remodeling, transcription, and mRNA splicing. These liquid compartments, called membrane-less organelles (MLOs), are formed by liquid–liquid phase separation (LLPS), selectively partitioning a specific set of macromolecules from others. While RNA binding proteins (RBPs) with low complexity regions (LCRs) appear to play an essential role in this process, the role of RNAs is not well-understood. It appears that short nonspecific RNAs keep the RBPs in a soluble state, while longer RNAs with unique secondary structures promote LLPS formation by specifically binding to RBPs. This review will update the current understanding of phase separation, physio-chemical nature and composition of condensates, regulation of phase separation, the role of lncRNA in the phase separation process, and the relevance to cancer development and progression.
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43
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Carro MDLM, Grimson A, Cohen PE. Small RNAs and their protein partners in animal meiosis. Curr Top Dev Biol 2022; 151:245-279. [PMID: 36681472 DOI: 10.1016/bs.ctdb.2022.06.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Meiosis is characterized by highly regulated transitions in gene expression that require diverse mechanisms of gene regulation. For example, in male mammals, transcription undergoes a global shut-down in early prophase I of meiosis, followed by increasing transcriptional activity into pachynema. Later, as spermiogenesis proceeds, the histones bound to DNA are replaced with transition proteins, which are themselves replaced with protamines, resulting in a highly condensed nucleus with repressed transcriptional activity. In addition, two specialized gene silencing events take place during prophase I: meiotic silencing of unsynapsed chromatin (MSUC), and the sex chromatin specific mechanism, meiotic sex chromosome inactivation (MSCI). Notably, conserved roles for the RNA binding protein (RBP) machinery that functions with small non-coding RNAs have been described as participating in these meiosis-specific mechanisms, suggesting that RNA-mediated gene regulation is critical for fertility in many species. Here, we review roles of small RNAs and their associated RBPs in meiosis-related processes such as centromere function, silencing of unpaired chromatin and meiotic recombination. We will discuss the emerging evidence of non-canonical functions of these components in meiosis.
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Affiliation(s)
- María de Las Mercedes Carro
- Department of Biomedical Sciences, Cornell University, Ithaca, NY, United States; Cornell Reproductive Sciences Center (CoRe), Cornell University, Ithaca, NY, United States
| | - Andrew Grimson
- Cornell Reproductive Sciences Center (CoRe), Cornell University, Ithaca, NY, United States; Department of Molecular Biology & Genetics, Cornell University, Ithaca, NY, United States.
| | - Paula E Cohen
- Department of Biomedical Sciences, Cornell University, Ithaca, NY, United States; Cornell Reproductive Sciences Center (CoRe), Cornell University, Ithaca, NY, United States.
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44
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Hijacking of transcriptional condensates by endogenous retroviruses. Nat Genet 2022; 54:1238-1247. [PMID: 35864192 PMCID: PMC9355880 DOI: 10.1038/s41588-022-01132-w] [Citation(s) in RCA: 31] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Accepted: 05/26/2022] [Indexed: 12/20/2022]
Abstract
Most endogenous retroviruses (ERVs) in mammals are incapable of retrotransposition; therefore, why ERV derepression is associated with lethality during early development has been a mystery. Here, we report that rapid and selective degradation of the heterochromatin adapter protein TRIM28 triggers dissociation of transcriptional condensates from loci encoding super-enhancer (SE)-driven pluripotency genes and their association with transcribed ERV loci in murine embryonic stem cells. Knockdown of ERV RNAs or forced expression of SE-enriched transcription factors rescued condensate localization at SEs in TRIM28-degraded cells. In a biochemical reconstitution system, ERV RNA facilitated partitioning of RNA polymerase II and the Mediator coactivator into phase-separated droplets. In TRIM28 knockout mouse embryos, single-cell RNA-seq analysis revealed specific depletion of pluripotent lineages. We propose that coding and noncoding nascent RNAs, including those produced by retrotransposons, may facilitate ‘hijacking’ of transcriptional condensates in various developmental and disease contexts. TRIM28 depletion in embryonic stem cells disconnects transcriptional condensates from super-enhancers, which is rescued by knockdown of endogenous retroviruses.
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45
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Wei C, Jia L, Huang X, Tan J, Wang M, Niu J, Hou Y, Sun J, Zeng P, Wang J, Qing L, Ma L, Liu X, Tang X, Li F, Jiang S, Liu J, Li T, Fan L, Sun Y, Gao J, Li C, Ding J. CTCF organizes inter-A compartment interactions through RYBP-dependent phase separation. Cell Res 2022; 32:744-760. [PMID: 35768498 PMCID: PMC9343660 DOI: 10.1038/s41422-022-00676-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Accepted: 05/10/2022] [Indexed: 12/13/2022] Open
Abstract
Chromatin is spatially organized into three-dimensional structures at different levels including A/B compartments, topologically associating domains and loops. The canonical CTCF-mediated loop extrusion model can explain the formation of loops. However, the organization mechanisms underlying long-range chromatin interactions such as interactions between A-A compartments are still poorly understood. Here we show that different from the canonical loop extrusion model, RYBP-mediated phase separation of CTCF organizes inter-A compartment interactions. Based on this model, we designed and verified an induced CTCF phase separation system in embryonic stem cells (ESCs), which facilitated inter-A compartment interactions, improved self-renewal of ESCs and inhibited their differentiation toward neural progenitor cells. These findings support a novel and non-canonical role of CTCF in organizing long-range chromatin interactions via phase separation.
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Affiliation(s)
- Chao Wei
- RNA Biomedical Institute, Sun Yat-Sen Memorial Hospital, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong, China.,Advanced Medical Technology Center, The First Affiliated Hospital, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, China.,Center for Stem Cell Biology and Tissue Engineering, Key Laboratory for Stem Cells and Tissue Engineering, Ministry of Education, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong, China
| | - Lumeng Jia
- School of Life Sciences, Peking University, Beijing, China
| | - Xiaona Huang
- RNA Biomedical Institute, Sun Yat-Sen Memorial Hospital, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong, China.,Advanced Medical Technology Center, The First Affiliated Hospital, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, China.,Center for Stem Cell Biology and Tissue Engineering, Key Laboratory for Stem Cells and Tissue Engineering, Ministry of Education, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong, China
| | - Jin Tan
- RNA Biomedical Institute, Sun Yat-Sen Memorial Hospital, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong, China.,Advanced Medical Technology Center, The First Affiliated Hospital, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, China.,Center for Stem Cell Biology and Tissue Engineering, Key Laboratory for Stem Cells and Tissue Engineering, Ministry of Education, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong, China
| | - Mulan Wang
- RNA Biomedical Institute, Sun Yat-Sen Memorial Hospital, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong, China.,Advanced Medical Technology Center, The First Affiliated Hospital, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, China.,Center for Stem Cell Biology and Tissue Engineering, Key Laboratory for Stem Cells and Tissue Engineering, Ministry of Education, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong, China
| | - Jing Niu
- School of Medicine, Tsinghua University, Beijing, China
| | - Yingping Hou
- Peking-Tsinghua Center for Life Sciences; Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China
| | - Jun Sun
- RNA Biomedical Institute, Sun Yat-Sen Memorial Hospital, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong, China.,Advanced Medical Technology Center, The First Affiliated Hospital, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, China.,Center for Stem Cell Biology and Tissue Engineering, Key Laboratory for Stem Cells and Tissue Engineering, Ministry of Education, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong, China
| | - Pengguihang Zeng
- RNA Biomedical Institute, Sun Yat-Sen Memorial Hospital, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong, China.,Advanced Medical Technology Center, The First Affiliated Hospital, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, China.,Center for Stem Cell Biology and Tissue Engineering, Key Laboratory for Stem Cells and Tissue Engineering, Ministry of Education, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong, China.,Department of Cell Biology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, Guangdong, China
| | - Jia Wang
- RNA Biomedical Institute, Sun Yat-Sen Memorial Hospital, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong, China.,Advanced Medical Technology Center, The First Affiliated Hospital, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, China.,Center for Stem Cell Biology and Tissue Engineering, Key Laboratory for Stem Cells and Tissue Engineering, Ministry of Education, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong, China
| | - Li Qing
- RNA Biomedical Institute, Sun Yat-Sen Memorial Hospital, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong, China.,Advanced Medical Technology Center, The First Affiliated Hospital, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, China.,Center for Stem Cell Biology and Tissue Engineering, Key Laboratory for Stem Cells and Tissue Engineering, Ministry of Education, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong, China
| | - Lin Ma
- RNA Biomedical Institute, Sun Yat-Sen Memorial Hospital, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong, China.,Advanced Medical Technology Center, The First Affiliated Hospital, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, China.,Center for Stem Cell Biology and Tissue Engineering, Key Laboratory for Stem Cells and Tissue Engineering, Ministry of Education, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong, China
| | - Xinyi Liu
- RNA Biomedical Institute, Sun Yat-Sen Memorial Hospital, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong, China.,Advanced Medical Technology Center, The First Affiliated Hospital, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, China.,Center for Stem Cell Biology and Tissue Engineering, Key Laboratory for Stem Cells and Tissue Engineering, Ministry of Education, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong, China
| | - Xiuxiao Tang
- RNA Biomedical Institute, Sun Yat-Sen Memorial Hospital, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong, China.,Advanced Medical Technology Center, The First Affiliated Hospital, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, China.,Center for Stem Cell Biology and Tissue Engineering, Key Laboratory for Stem Cells and Tissue Engineering, Ministry of Education, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong, China
| | - Fenjie Li
- RNA Biomedical Institute, Sun Yat-Sen Memorial Hospital, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong, China.,Advanced Medical Technology Center, The First Affiliated Hospital, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, China.,Center for Stem Cell Biology and Tissue Engineering, Key Laboratory for Stem Cells and Tissue Engineering, Ministry of Education, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong, China.,Department of Pediatric Surgery, Guangdong Provincial Key Laboratory of Research in Structural Birth Defect Disease, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, Guangdong, China
| | - Shaoshuai Jiang
- RNA Biomedical Institute, Sun Yat-Sen Memorial Hospital, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong, China.,Advanced Medical Technology Center, The First Affiliated Hospital, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, China.,Center for Stem Cell Biology and Tissue Engineering, Key Laboratory for Stem Cells and Tissue Engineering, Ministry of Education, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong, China
| | - Jingxin Liu
- RNA Biomedical Institute, Sun Yat-Sen Memorial Hospital, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong, China.,Advanced Medical Technology Center, The First Affiliated Hospital, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, China.,Center for Stem Cell Biology and Tissue Engineering, Key Laboratory for Stem Cells and Tissue Engineering, Ministry of Education, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong, China
| | - Tingting Li
- State Key Laboratory of Proteomics, National Center of Biomedical Analysis, Institute of Basic Medical Sciences, Beijing, China
| | - Lili Fan
- Guangzhou Key Laboratory of Formula-Pattern of Traditional Chinese Medicine, School of Traditional Chinese Medicine, Jinan University, Guangzhou, Guangdong, China
| | - Yujie Sun
- School of Life Sciences, Peking University, Beijing, China.,State Key Laboratory of Membrane Biology, Biomedical pioneering innovation center (BIOPIC), Peking University, Beijing, China
| | - Juntao Gao
- MOE Key Laboratory of Bioinformatics; Bioinformatics Division, BNRist; Department of Automation; Center for Synthetic & Systems Biology, Tsinghua University, Beijing, China
| | - Cheng Li
- School of Life Sciences, Peking University, Beijing, China. .,Center for Bioinformatics, Center for Statistical Science, Peking University, Beijing, China.
| | - Junjun Ding
- RNA Biomedical Institute, Sun Yat-Sen Memorial Hospital, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong, China. .,Advanced Medical Technology Center, The First Affiliated Hospital, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, China. .,Center for Stem Cell Biology and Tissue Engineering, Key Laboratory for Stem Cells and Tissue Engineering, Ministry of Education, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong, China.
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46
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Novo CL, Wong EV, Hockings C, Poudel C, Sheekey E, Wiese M, Okkenhaug H, Boulton SJ, Basu S, Walker S, Kaminski Schierle GS, Narlikar GJ, Rugg-Gunn PJ. Satellite repeat transcripts modulate heterochromatin condensates and safeguard chromosome stability in mouse embryonic stem cells. Nat Commun 2022; 13:3525. [PMID: 35725842 PMCID: PMC9209518 DOI: 10.1038/s41467-022-31198-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Accepted: 06/07/2022] [Indexed: 12/25/2022] Open
Abstract
Heterochromatin maintains genome integrity and function, and is organised into distinct nuclear domains. Some of these domains are proposed to form by phase separation through the accumulation of HP1ɑ. Mouse heterochromatin contains noncoding major satellite repeats (MSR), which are highly transcribed in mouse embryonic stem cells (ESCs). Here, we report that MSR transcripts can drive the formation of HP1ɑ droplets in vitro, and modulate heterochromatin into dynamic condensates in ESCs, contributing to the formation of large nuclear domains that are characteristic of pluripotent cells. Depleting MSR transcripts causes heterochromatin to transition into a more compact and static state. Unexpectedly, changing heterochromatin's biophysical properties has severe consequences for ESCs, including chromosome instability and mitotic defects. These findings uncover an essential role for MSR transcripts in modulating the organisation and properties of heterochromatin to preserve genome stability. They also provide insights into the processes that could regulate phase separation and the functional consequences of disrupting the properties of heterochromatin condensates.
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Affiliation(s)
- Clara Lopes Novo
- Epigenetics Programme, The Babraham Institute, Babraham Research Campus, Cambridge, CB22 3AT, UK.
- Tommy's National Miscarriage Research Centre at Imperial College London, London, W12 0NN, UK.
- The Francis Crick Institute, 1 Midland Road, London, NW1 1AT, UK.
| | - Emily V Wong
- Department of Biochemistry and Biophysics, University of California San Francisco, San Francisco, CA, USA
| | - Colin Hockings
- Department of Chemical Engineering and Biotechnology, University of Cambridge, Cambridge, CB3 0AS, UK
| | - Chetan Poudel
- Department of Chemical Engineering and Biotechnology, University of Cambridge, Cambridge, CB3 0AS, UK
| | - Eleanor Sheekey
- Epigenetics Programme, The Babraham Institute, Babraham Research Campus, Cambridge, CB22 3AT, UK
| | - Meike Wiese
- Wellcome - Medical Research Council Cambridge Stem Cell Institute, University of Cambridge, Cambridge, CB2 1QR, UK
| | - Hanneke Okkenhaug
- Imaging Facility, The Babraham Institute, Babraham Research Campus, Cambridge, CB22 3AT, UK
| | - Simon J Boulton
- The Francis Crick Institute, 1 Midland Road, London, NW1 1AT, UK
- Artios Pharma Ltd., B940, Babraham Research Campus, Cambridge, CB22 3FH, UK
| | - Srinjan Basu
- Wellcome - Medical Research Council Cambridge Stem Cell Institute, University of Cambridge, Cambridge, CB2 1QR, UK
| | - Simon Walker
- Imaging Facility, The Babraham Institute, Babraham Research Campus, Cambridge, CB22 3AT, UK
| | | | - Geeta J Narlikar
- Department of Biochemistry and Biophysics, University of California San Francisco, San Francisco, CA, USA
| | - Peter J Rugg-Gunn
- Epigenetics Programme, The Babraham Institute, Babraham Research Campus, Cambridge, CB22 3AT, UK.
- Wellcome - Medical Research Council Cambridge Stem Cell Institute, University of Cambridge, Cambridge, CB2 1QR, UK.
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Cao L, Luo Y, Guo X, Liu S, Li S, Li J, Zhang Z, Zhao Y, Zhang Q, Gao F, Ji X, Gao X, Li Y, You F. SAFA facilitates chromatin opening of immune genes through interacting with anti-viral host RNAs. PLoS Pathog 2022; 18:e1010599. [PMID: 35658050 PMCID: PMC9200321 DOI: 10.1371/journal.ppat.1010599] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Revised: 06/15/2022] [Accepted: 05/17/2022] [Indexed: 12/19/2022] Open
Abstract
Regulation of chromatin structure and accessibility determines the transcription activities of genes, which endows the host with function-specific patterns of gene expression. Upon viral infection, the innate immune responses provide the first line of defense, allowing rapid production of variegated antiviral cytokines. Knowledge on how chromatin accessibility is regulated during host defense against viral infection remains limited. Our previous work found that the nuclear matrix protein SAFA surveilled viral RNA and regulated antiviral immune genes expression. However, how SAFA regulates the specific induction of antiviral immune genes remains unknown. Here, through integration of RNA-seq, ATAC-seq and ChIP-seq assays, we found that the depletion of SAFA specifically decreased the chromatin accessibility, activation and expression of virus induced genes. And mutation assays suggested that the RNA-binding ability of SAFA was essential for its function in regulating antiviral chromatin accessibility. RIP-seq results showed that SAFA exclusively bound with antiviral related RNAs following viral infection. Further, we combined the CRISPR-Cas13d mediated RNA knockdown system with ATAC-qPCR, and demonstrated that the binding between SAFA and according antiviral RNAs specifically mediated the openness of the corresponding chromatin and following robust transcription of antiviral genes. Moreover, knockdown of these associated RNAs dampened the accessibility of related genes in an extranuclear signaling pathway dependent manner. Interestingly, VSV infection cleaved SAFA protein at the C-terminus which deprived its RNA binding ability for immune evasion. Thus, our results demonstrated that SAFA and the interacting RNA products collaborated and remodeled chromatin accessibility to facilitate antiviral innate immune responses. Regulation of chromatin opening and gene expression underlies a key point during host defense against viral infection, which endows the host with timely and effective antiviral gene expression patterns. We previously reported that the nuclear matrix protein SAFA surveils viral RNA and regulates antiviral immune genes expression. However, how SAFA regulates the expression and what determines the specific induction of antiviral immune genes remains unclear. Here, we used a combination of high-throughput sequencing technologies and found that SAFA and the interacting RNA products collaborated and specifically remodeled chromatin accessibility to facilitate antiviral immune genes expression. We also found that VSV infection cleaved SAFA protein at the C-terminus and deprived its RNA binding ability for immune evasion. Our study provides new insights into the mechanism by which chromatin remodeling facilitates the induction of antiviral immune genes.
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Affiliation(s)
- Lili Cao
- Department of Immunology, School of Basic Medical Sciences, Beijing Key Laboratory of Tumor Systems Biology, Institute of Systems Biomedicine, Peking University Health Science Center, Beijing, China
- Beijing Institutes of Life Science, Chinese Academy of Sciences, Beijing, China
| | - Yujie Luo
- Department of Immunology, School of Basic Medical Sciences, Beijing Key Laboratory of Tumor Systems Biology, Institute of Systems Biomedicine, Peking University Health Science Center, Beijing, China
| | - Xuefei Guo
- Department of Immunology, School of Basic Medical Sciences, Beijing Key Laboratory of Tumor Systems Biology, Institute of Systems Biomedicine, Peking University Health Science Center, Beijing, China
| | - Shengde Liu
- Department of Gastrointestinal Oncology, Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Peking University Cancer Hospital and Institute, Beijing, China
| | - Siji Li
- Department of Immunology, School of Basic Medical Sciences, Beijing Key Laboratory of Tumor Systems Biology, Institute of Systems Biomedicine, Peking University Health Science Center, Beijing, China
| | - Junhong Li
- CAS Key Laboratory of Infection and Immunity, National Laboratory of Macromolecules, Institute of Biophysics, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing, China
| | - Zeming Zhang
- Department of Immunology, School of Basic Medical Sciences, Beijing Key Laboratory of Tumor Systems Biology, Institute of Systems Biomedicine, Peking University Health Science Center, Beijing, China
| | - Yingchi Zhao
- Department of Immunology, School of Basic Medical Sciences, Beijing Key Laboratory of Tumor Systems Biology, Institute of Systems Biomedicine, Peking University Health Science Center, Beijing, China
| | - Qiao Zhang
- School of Medicine, Jinan University, Guangzhou, Guangdong, China
| | - Feng Gao
- School of Medicine, Jinan University, Guangzhou, Guangdong, China
| | - Xiong Ji
- Key Laboratory of Cell Proliferation and Differentiation of the Ministry of Education, School of Life Sciences, Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, China
| | - Xiang Gao
- State Key Laboratory of Microbial Technology, Microbial Technology Institute, School of life science, Shandong University, Qingdao, China
| | - Yunfei Li
- Department of Immunology, School of Basic Medical Sciences, Beijing Key Laboratory of Tumor Systems Biology, Institute of Systems Biomedicine, Peking University Health Science Center, Beijing, China
- * E-mail: (YL); (FY)
| | - Fuping You
- Department of Immunology, School of Basic Medical Sciences, Beijing Key Laboratory of Tumor Systems Biology, Institute of Systems Biomedicine, Peking University Health Science Center, Beijing, China
- * E-mail: (YL); (FY)
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48
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Substoichiometric action of long noncoding RNAs. Nat Cell Biol 2022; 24:608-615. [PMID: 35562482 DOI: 10.1038/s41556-022-00911-1] [Citation(s) in RCA: 32] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Accepted: 04/01/2022] [Indexed: 11/08/2022]
Abstract
Low expression levels and stoichiometric imbalances of long noncoding RNAs (lncRNAs) are often used as evidence for their probable lack of function or for limiting the scope of their potential influence. Recent advances in our understanding of the substoichiometric functions of lncRNAs challenge these notions and suggest routes through which unabundant lncRNAs can affect cellular functions and gene regulatory networks.
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49
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Ron M, Ulitsky I. Context-specific effects of sequence elements on subcellular localization of linear and circular RNAs. Nat Commun 2022; 13:2481. [PMID: 35513423 PMCID: PMC9072321 DOI: 10.1038/s41467-022-30183-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Accepted: 04/05/2022] [Indexed: 12/24/2022] Open
Abstract
Long RNAs vary extensively in their post-transcriptional fates, and this variation is attributed in part to short sequence elements. We used massively parallel RNA assays to study how sequences derived from noncoding RNAs influence the subcellular localization and stability of circular and linear RNAs, including spliced and unspliced forms. We find that the effects of sequence elements strongly depend on the host RNA context, with limited overlap between sequences that drive nuclear enrichment of linear and circular RNAs. Binding of specific RNA binding proteins underpins some of these differences-SRSF1 binding leads to nuclear enrichment of circular RNAs; SAFB binding is associated with nuclear enrichment of predominantly unspliced linear RNAs; and IGF2BP1 promotes export of linear spliced RNA molecules. The post-transcriptional fate of long RNAs is thus dictated by combinatorial contributions of specific sequence elements, of splicing, and of the presence of the terminal features unique to linear RNAs.
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Affiliation(s)
- Maya Ron
- Departments of Biological Regulation and Molecular Neuroscience, Weizmann Institute of Science, Rehovot, 76100, Israel
| | - Igor Ulitsky
- Departments of Biological Regulation and Molecular Neuroscience, Weizmann Institute of Science, Rehovot, 76100, Israel.
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50
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Long-Distance Repression by Human Silencers: Chromatin Interactions and Phase Separation in Silencers. Cells 2022; 11:cells11091560. [PMID: 35563864 PMCID: PMC9101175 DOI: 10.3390/cells11091560] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Revised: 05/01/2022] [Accepted: 05/02/2022] [Indexed: 12/12/2022] Open
Abstract
Three-dimensional genome organization represents an additional layer in the epigenetic regulation of gene expression. Active transcription controlled by enhancers or super-enhancers has been extensively studied. Enhancers or super-enhancers can recruit activators or co-activators to activate target gene expression through long-range chromatin interactions. Chromatin interactions and phase separation play important roles in terms of enhancer or super-enhancer functioning. Silencers are another major type of cis-regulatory element that can mediate gene regulation by turning off or reducing gene expression. However, compared to active transcription, silencer studies are still in their infancy. This review covers the current knowledge of human silencers, especially the roles of chromatin interactions and phase separation in silencers. This review also proposes future directions for human silencer studies.
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