1
|
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.
Collapse
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
| |
Collapse
|
2
|
Keidel A, Kögel A, Reichelt P, Kowalinski E, Schäfer IB, Conti E. Concerted structural rearrangements enable RNA channeling into the cytoplasmic Ski238-Ski7-exosome assembly. Mol Cell 2023; 83:4093-4105.e7. [PMID: 37879335 PMCID: PMC10659929 DOI: 10.1016/j.molcel.2023.09.037] [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: 06/06/2023] [Revised: 08/25/2023] [Accepted: 09/29/2023] [Indexed: 10/27/2023]
Abstract
The Ski2-Ski3-Ski8 (Ski238) helicase complex directs cytoplasmic mRNAs toward the nucleolytic exosome complex for degradation. In yeast, the interaction between Ski238 and exosome requires the adaptor protein Ski7. We determined different cryo-EM structures of the Ski238 complex depicting the transition from a rigid autoinhibited closed conformation to a flexible active open conformation in which the Ski2 helicase module has detached from the rest of Ski238. The open conformation favors the interaction of the Ski3 subunit with exosome-bound Ski7, leading to the recruitment of the exosome. In the Ski238-Ski7-exosome holocomplex, the Ski2 helicase module binds the exosome cap, enabling the RNA to traverse from the helicase through the internal exosome channel to the Rrp44 exoribonuclease. Our study pinpoints how conformational changes within the Ski238 complex regulate exosome recruitment for RNA degradation. We also reveal the remarkable conservation of helicase-exosome RNA channeling mechanisms throughout eukaryotic nuclear and cytoplasmic exosome complexes.
Collapse
Affiliation(s)
- Achim Keidel
- Department of Structural Cell Biology, Max Planck Institute of Biochemistry, Am Klopferspitz 18, Martinsried, 82152 Munich, Germany
| | - Alexander Kögel
- Department of Structural Cell Biology, Max Planck Institute of Biochemistry, Am Klopferspitz 18, Martinsried, 82152 Munich, Germany
| | - Peter Reichelt
- Department of Structural Cell Biology, Max Planck Institute of Biochemistry, Am Klopferspitz 18, Martinsried, 82152 Munich, Germany
| | - Eva Kowalinski
- EMBL Grenoble, 71 Avenue des Martyrs, 38072 Grenoble, France
| | - Ingmar B Schäfer
- Department of Structural Cell Biology, Max Planck Institute of Biochemistry, Am Klopferspitz 18, Martinsried, 82152 Munich, Germany
| | - Elena Conti
- Department of Structural Cell Biology, Max Planck Institute of Biochemistry, Am Klopferspitz 18, Martinsried, 82152 Munich, Germany.
| |
Collapse
|
3
|
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/ ).
Collapse
|
4
|
He Y, Xue Y, Wang J, Huang Y, Liu L, Huang Y, Gao YQ. Diffusion-enhanced characterization of 3D chromatin structure reveals its linkage to gene regulatory networks and the interactome. Genome Res 2023; 33:1354-1368. [PMID: 37491077 PMCID: PMC10547250 DOI: 10.1101/gr.277737.123] [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: 01/24/2023] [Accepted: 07/21/2023] [Indexed: 07/27/2023]
Abstract
The interactome networks at the DNA, RNA, and protein levels are crucial for cellular functions, and the diverse variations of these networks are heavily involved in the establishment of different cell states. We have developed a diffusion-based method, Hi-C to geometry (CTG), to obtain reliable geometric information on the chromatin from Hi-C data. CTG produces a consistent and reproducible framework for the 3D genomic structure and provides a reliable and quantitative understanding of the alterations of genomic structures under different cellular conditions. The genomic structure yielded by CTG serves as an architectural blueprint of the dynamic gene regulatory network, based on which cell-specific correspondence between gene-gene and corresponding protein-protein physical interactions, as well as transcription correlation, is revealed. We also find that gene fusion events are significantly enriched between genes of short CTG distances and are thus close in 3D space. These findings indicate that 3D chromatin structure is at least partially correlated with downstream processes such as transcription, gene regulation, and even regulatory networking through affecting protein-protein interactions.
Collapse
Affiliation(s)
- Yueying He
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
| | - Yue Xue
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
| | - Jingyao Wang
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
| | - Yupeng Huang
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
| | - Lu Liu
- Biomedical Pioneering Innovation Center (BIOPIC), Peking University, Beijing 100871, China
- School of Life Sciences, Peking University, Beijing 100871, China
| | - Yanyi Huang
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China;
- Biomedical Pioneering Innovation Center (BIOPIC), Peking University, Beijing 100871, China
| | - Yi Qin Gao
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China;
- Biomedical Pioneering Innovation Center (BIOPIC), Peking University, Beijing 100871, China
| |
Collapse
|
5
|
Ye H, Tan L, Tu C, Min L. Exosomes in sarcoma: Prospects for clinical applications. Crit Rev Oncol Hematol 2023; 181:103895. [PMID: 36481305 DOI: 10.1016/j.critrevonc.2022.103895] [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: 09/02/2022] [Revised: 11/23/2022] [Accepted: 12/01/2022] [Indexed: 12/12/2022] Open
Abstract
Sarcoma is a group of rare and heterogeneous mesenchymal tumors, prone to late diagnosis and poor prognosis. Exosomes are cell-derived small extracellular vesicles found in most body fluids and contain nucleic acids, proteins, lipids, and other molecules. Qualitative and quantitative changes of exosomes and the contents are associated with sarcoma progression, exhibiting their potential as biomarkers. Exosomes possess the capacity of evading immune responses, bioactivity for trafficking, tumor tropism, and lesion residence. Thus, exosomes could be engineered as tumor-specific vehicles in drugs and RNA delivery systems. Exosomes might also serve as therapeutic targets in targeted therapy and immunotherapy and be involved in chemotherapy resistance. Here, we provide a comprehensive summary of exosome applications in liquid biopsy-based diagnosis and explore their implications in the delivery system, targeted therapy, and chemotherapy resistance of sarcoma. Moreover, challenges in exosome clinical applications are raised and some future research directions are proposed.
Collapse
Affiliation(s)
- Huali Ye
- West China Hospital, West China School of Medicine, Sichuan University, Guoxue Xiang No. 37, Chengdu 610041, Sichuan, People's Republic of China
| | - Linyun Tan
- Orthopaedic Research Institute, Department of Orthopaedics, West China Hospital, Sichuan University, Guoxue Xiang No. 37, Chengdu 610041, Sichuan, People's Republic of China
| | - Chongqi Tu
- Orthopaedic Research Institute, Department of Orthopaedics, West China Hospital, Sichuan University, Guoxue Xiang No. 37, Chengdu 610041, Sichuan, People's Republic of China
| | - Li Min
- Orthopaedic Research Institute, Department of Orthopaedics, West China Hospital, Sichuan University, Guoxue Xiang No. 37, Chengdu 610041, Sichuan, People's Republic of China.
| |
Collapse
|
6
|
Wu S, Tian P, Tan T. CRISPR-Cas13 technology portfolio and alliance with other genetic tools. Biotechnol Adv 2022; 61:108047. [DOI: 10.1016/j.biotechadv.2022.108047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Revised: 09/03/2022] [Accepted: 09/29/2022] [Indexed: 11/02/2022]
|
7
|
Zhang Y, Chen C, Liu Z, Guo H, Lu W, Hu W, Lin Z. PABPC1-induced stabilization of IFI27 mRNA promotes angiogenesis and malignant progression in esophageal squamous cell carcinoma through exosomal miRNA-21-5p. J Exp Clin Cancer Res 2022; 41:111. [PMID: 35346324 PMCID: PMC8962095 DOI: 10.1186/s13046-022-02339-9] [Citation(s) in RCA: 34] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Accepted: 03/21/2022] [Indexed: 02/05/2023] Open
Abstract
BACKGROUND Emerging evidence has demonstrated that RNA-binding protein dysregulation is involved in esophageal squamous cell carcinoma (ESCC) progression. However, the role of poly (A) binding protein cytoplasmic 1 (PABPC1) in ESCC is unclear. We therefore aimed to explore the functions and potential mechanisms of PABPC1 in ESCC progression. METHODS PABPC1 expression was characterized using immunohistochemistry and qRT-PCR in ESCC tissues and cell lines. Chromatin immunoprecipitation (ChIP) and luciferase reporter assays were used to detect histone acetylation in the promoter region of PABPC1. A series of in vitro and in vivo assays were further applied to elucidate the functions and underlying molecular mechanisms of PABPC1 in ESCC angiogenesis and malignant procession. RESULTS PABPC1 expression was upregulated in ESCC tissues compared with in normal esophageal epithelial tissues. Elevated PABPC1 expression was correlated with tumor cell differentiation and poor prognosis in patients. Sp1 and p300 cooperated to increase the level of H2K37ac in the PABPC1 promoter. Functionally, PABPC1 overexpression enhanced esophageal squamous cell proliferation and invasion by activating the IFN/IFI27 signaling pathway. PABPC1 interacted with eIF4G to increase the stability of IFI27 mRNA by competing with RNA exosomes in ESCC. Furthermore, PABPC1/IFI27 could increase miR-21-5p expression to enable exosomal delivery of miR-21-5p to human umbilical vein endothelial cells to increase angiogenesis via inhibiting CXCL10. CONCLUSION PABPC1 plays a critical role in ESCC malignant progression by interacting with eIF4G to regulate IFI27 mRNA stability and promote angiogenesis via exosomal miR-21-5p/CXCL10. Taken together, our results suggest that PABPC1 is a promising therapeutic target for ESCC.
Collapse
Affiliation(s)
- Ying Zhang
- Department of Radiotherapy, Cancer Hospital of Shantou University Medical College, No. 7 Raoping Road, Shantou, Guangdong, 515041, China
- Guangdong Provincial Key Laboratory for Breast Cancer Diagnosis and Treatment, Cancer Hospital of Shantou University Medical College, Shantou, Guangdong, 515041, China
| | - Chuangzhen Chen
- Department of Radiotherapy, Cancer Hospital of Shantou University Medical College, No. 7 Raoping Road, Shantou, Guangdong, 515041, China
| | - Zhaoyong Liu
- Department of Orthopedics, First Affiliated Hospital of Shantou University Medical College, No.57 Changping Road, Shantou, 515041, Guangdong, China
| | - Huancheng Guo
- Department of Orthopedics, First Affiliated Hospital of Shantou University Medical College, No.57 Changping Road, Shantou, 515041, Guangdong, China
| | - Weiqing Lu
- Guangdong Provincial Key Laboratory for Breast Cancer Diagnosis and Treatment, Cancer Hospital of Shantou University Medical College, Shantou, Guangdong, 515041, China
| | - Wang Hu
- Department of Orthopedics, First Affiliated Hospital of Shantou University Medical College, No.57 Changping Road, Shantou, 515041, Guangdong, China
| | - Zhixiong Lin
- Department of Radiotherapy, Cancer Hospital of Shantou University Medical College, No. 7 Raoping Road, Shantou, Guangdong, 515041, China
| |
Collapse
|
8
|
Puno MR, Lima CD. Methods to assess helicase and translocation activities of human nuclear RNA exosome and RNA adaptor complexes. Methods Enzymol 2022; 673:453-473. [PMID: 35965016 PMCID: PMC9382703 DOI: 10.1016/bs.mie.2022.03.060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
The nuclear RNA exosome collaborates with the MTR4 helicase and RNA adaptor complexes to process, surveil, and degrade RNA. Here we outline methods to characterize RNA translocation and strand displacement by exosome-associated helicases and adaptor complexes using fluorescence-based strand displacement assays. The design and preparation of substrates suitable for analysis of helicase and decay activities of reconstituted MTR4–exosome complexes are described. To aid structural and biophysical studies, we present strategies for engineering substrates that can stall helicases during translocation, providing a means to capture snapshots of interactions and molecular steps involved in substrate translocation and delivery to the exosome.
Collapse
|
9
|
Slavotinek A, Misceo D, Htun S, Mathisen L, Frengen E, Foreman M, Hurtig JE, Enyenihi L, Sterrett MC, Leung SW, Schneidman-Duhovny D, Estrada-Veras J, Duncan JL, Haaxma CA, Kamsteeg EJ, Xia V, Beleford D, Si Y, Douglas G, Treidene HE, van Hoof A, Fasken MB, Corbett AH. Biallelic variants in the RNA exosome gene EXOSC5 are associated with developmental delays, short stature, cerebellar hypoplasia and motor weakness. Hum Mol Genet 2021; 29:2218-2239. [PMID: 32504085 DOI: 10.1093/hmg/ddaa108] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2020] [Revised: 05/10/2020] [Accepted: 05/28/2020] [Indexed: 12/15/2022] Open
Abstract
The RNA exosome is an essential ribonuclease complex required for processing and/or degradation of both coding and non-coding RNAs. We identified five patients with biallelic variants in EXOSC5, which encodes a structural subunit of the RNA exosome. The clinical features of these patients include failure to thrive, short stature, feeding difficulties, developmental delays that affect motor skills, hypotonia and esotropia. Brain MRI revealed cerebellar hypoplasia and ventriculomegaly. While we ascertained five patients, three patients with distinct variants of EXOSC5 were studied in detail. The first patient had a deletion involving exons 5-6 of EXOSC5 and a missense variant, p.Thr114Ile, that were inherited in trans, the second patient was homozygous for p.Leu206His and the third patient had paternal isodisomy for chromosome 19 and was homozygous for p.Met148Thr. The additional two patients ascertained are siblings who had an early frameshift mutation in EXOSC5 and the p.Thr114Ile missense variant that were inherited in trans. We employed three complementary approaches to explore the requirement for EXOSC5 in brain development and assess consequences of pathogenic EXOSC5 variants. Loss of function for exosc5 in zebrafish results in shortened and curved tails/bodies, reduced eye/head size and edema. We modeled pathogenic EXOSC5 variants in both budding yeast and mammalian cells. Some of these variants cause defects in RNA exosome function as well as altered interactions with other RNA exosome subunits. These findings expand the number of genes encoding RNA exosome subunits linked to human disease while also suggesting that disease mechanism varies depending on the specific pathogenic variant.
Collapse
Affiliation(s)
- Anne Slavotinek
- Department of Pediatrics, University of California, San Francisco, CA 94143, USA
| | - Doriana Misceo
- Department of Medical Genetics, Oslo University Hospital and University of Oslo, Oslo 0450, Norway
| | - Stephanie Htun
- Department of Pediatrics, University of California, San Francisco, CA 94143, USA
| | - Linda Mathisen
- Department of Medical Genetics, Oslo University Hospital and University of Oslo, Oslo 0450, Norway
| | - Eirik Frengen
- Department of Medical Genetics, Oslo University Hospital and University of Oslo, Oslo 0450, Norway
| | - Michelle Foreman
- Department of Microbiology and Molecular Genetics, University of Texas Health Science Center-Houston, Houston, TX 77030, USA
| | - Jennifer E Hurtig
- Department of Microbiology and Molecular Genetics, University of Texas Health Science Center-Houston, Houston, TX 77030, USA
| | - Liz Enyenihi
- Department of Biology, Emory University, Atlanta, GA 30322, USA
| | | | - Sara W Leung
- Department of Biology, Emory University, Atlanta, GA 30322, USA
| | - Dina Schneidman-Duhovny
- School of Computer Science and Engineering and the Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Juvianee Estrada-Veras
- Department of Pediatrics-Medical Genetics and Metabolism, Uniformed Services University/Walter Reed NMMC Bethesda, MD 20889, USA
| | - Jacque L Duncan
- Department of Ophthalmology, University of California, San Francisco, CA 94143, USA
| | - Charlotte A Haaxma
- Department of Pediatric Neurology, Amalia Children's Hospital and Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen 6500 HB, The Netherlands
| | - Erik-Jan Kamsteeg
- Department of Human Genetics, Radboud University Medical Center, Nijmegen 6500 HB, The Netherlands
| | - Vivian Xia
- Department of Pediatrics, University of California, San Francisco, CA 94143, USA
| | - Daniah Beleford
- Department of Pediatrics, University of California, San Francisco, CA 94143, USA
| | - Yue Si
- GeneDx Inc., MD 20877, USA
| | | | - Hans Einar Treidene
- Department of Radiology and Nuclear Medicine, Oslo University Hospital, Oslo 0450, Norway
| | - Ambro van Hoof
- Department of Microbiology and Molecular Genetics, University of Texas Health Science Center-Houston, Houston, TX 77030, USA
| | - Milo B Fasken
- Department of Biology, Emory University, Atlanta, GA 30322, USA
| | - Anita H Corbett
- Department of Biology, Emory University, Atlanta, GA 30322, USA
| |
Collapse
|
10
|
Machado de Amorim A, Chakrabarti S. Assembly of multicomponent machines in RNA metabolism: A common theme in mRNA decay pathways. WILEY INTERDISCIPLINARY REVIEWS-RNA 2021; 13:e1684. [PMID: 34351053 DOI: 10.1002/wrna.1684] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 07/07/2021] [Accepted: 07/08/2021] [Indexed: 11/05/2022]
Abstract
Multicomponent protein-RNA complexes comprising a ribonuclease and partner RNA helicase facilitate the turnover of mRNA in all domains of life. While these higher-order complexes provide an effective means of physically and functionally coupling the processes of RNA remodeling and decay, most ribonucleases and RNA helicases do not exhibit sequence specificity in RNA binding. This raises the question as to how these assemblies select substrates for processing and how the activities are orchestrated at the precise moment to ensure efficient decay. The answers to these apparent puzzles lie in the auxiliary components of the assemblies that might relay decay-triggering signals. Given their function within the assemblies, these components may be viewed as "sensors." The functions and mechanisms of action of the sensor components in various degradation complexes in bacteria and eukaryotes are highlighted here to discuss their roles in RNA decay processes. This article is categorized under: RNA Turnover and Surveillance > Regulation of RNA Stability RNA Turnover and Surveillance > Turnover/Surveillance Mechanisms RNA Interactions with Proteins and Other Molecules > Protein-RNA Recognition.
Collapse
Affiliation(s)
| | - Sutapa Chakrabarti
- Institute of Chemistry and Biochemistry, Freie Universität Berlin, Berlin, Germany
| |
Collapse
|
11
|
Das M, Zattas D, Zinder JC, Wasmuth EV, Henri J, Lima CD. Substrate discrimination and quality control require each catalytic activity of TRAMP and the nuclear RNA exosome. Proc Natl Acad Sci U S A 2021; 118:e2024846118. [PMID: 33782132 PMCID: PMC8040639 DOI: 10.1073/pnas.2024846118] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Quality control requires discrimination between functional and aberrant species to selectively target aberrant substrates for destruction. Nuclear RNA quality control in Saccharomyces cerevisiae includes the TRAMP complex that marks RNA for decay via polyadenylation followed by helicase-dependent 3' to 5' degradation by the RNA exosome. Using reconstitution biochemistry, we show that polyadenylation and helicase activities of TRAMP cooperate with processive and distributive exoribonuclease activities of the nuclear RNA exosome to protect stable RNA from degradation while selectively targeting and degrading less stable RNA. Substrate discrimination is lost when the distributive exoribonuclease activity of Rrp6 is inactivated, leading to degradation of stable and unstable RNA species. These data support a proofreading mechanism in which deadenylation by Rrp6 competes with Mtr4-dependent degradation to protect stable RNA while selectively targeting and degrading unstable RNA.
Collapse
Affiliation(s)
- Mom Das
- Structural Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY 10065
| | - Dimitrios Zattas
- Structural Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY 10065
| | - John C Zinder
- Structural Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY 10065
- Tri-Institutional Training Program in Chemical Biology, Memorial Sloan Kettering Cancer Center, New York, NY 10065
| | - Elizabeth V Wasmuth
- Structural Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY 10065
| | - Julien Henri
- Structural Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY 10065
| | - Christopher D Lima
- Structural Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY 10065;
- HHMI, Memorial Sloan Kettering Cancer Center, New York, NY 10065
| |
Collapse
|
12
|
Tomecki R, Drazkowska K. An integrative approach uncovers transcriptome-wide determinants of mRNA stability regulation in Saccharomyces cerevisiae. FEBS J 2021; 288:3418-3423. [PMID: 33590687 DOI: 10.1111/febs.15742] [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: 01/19/2021] [Accepted: 01/29/2021] [Indexed: 11/29/2022]
Abstract
mRNA degradation rate is one of the key stages of gene expression regulation in eukaryotic cells. To date, intertwined processes of post-transcriptional control have been widely investigated, but focused rather on the examination of mechanisms controlling stability of particular protein-coding transcripts. Currently, a wealth of information from structural, biochemical, and high-throughput studies makes it tempting to define general rules governing mRNA stability that could be considered as versatile and valid on a genome-wide scale. Basu et al. analyzed multiple experimental and computational data on Saccharomyces cerevisiae mRNA half-lives as well as on secondary structures and protein-binding sites within transcripts, and collated it with available structures of ribonucleases, that is, enzymes responsible for mRNA degradation. This approach allowed to conclude how particular mRNA features such as lengths of unstructured terminal or internal regions or sequestration into ribonucleoprotein complexes impact half-lives of protein-coding transcripts and to define genome-scale principles of mRNA stability control in yeast.
Collapse
Affiliation(s)
- Rafal Tomecki
- Laboratory of RNA Biology, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland.,Institute of Genetics and Biotechnology, Faculty of Biology, University of Warsaw, Poland
| | | |
Collapse
|
13
|
RNA Metabolism Guided by RNA Modifications: The Role of SMUG1 in rRNA Quality Control. Biomolecules 2021; 11:biom11010076. [PMID: 33430019 PMCID: PMC7826747 DOI: 10.3390/biom11010076] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Revised: 12/29/2020] [Accepted: 01/05/2021] [Indexed: 12/19/2022] Open
Abstract
RNA modifications are essential for proper RNA processing, quality control, and maturation steps. In the last decade, some eukaryotic DNA repair enzymes have been shown to have an ability to recognize and process modified RNA substrates and thereby contribute to RNA surveillance. Single-strand-selective monofunctional uracil-DNA glycosylase 1 (SMUG1) is a base excision repair enzyme that not only recognizes and removes uracil and oxidized pyrimidines from DNA but is also able to process modified RNA substrates. SMUG1 interacts with the pseudouridine synthase dyskerin (DKC1), an enzyme essential for the correct assembly of small nucleolar ribonucleoproteins (snRNPs) and ribosomal RNA (rRNA) processing. Here, we review rRNA modifications and RNA quality control mechanisms in general and discuss the specific function of SMUG1 in rRNA metabolism. Cells lacking SMUG1 have elevated levels of immature rRNA molecules and accumulation of 5-hydroxymethyluridine (5hmU) in mature rRNA. SMUG1 may be required for post-transcriptional regulation and quality control of rRNAs, partly by regulating rRNA and stability.
Collapse
|
14
|
Basu S, Mallik S, Hait S, Kundu S. Genome-scale molecular principles of mRNA half-life regulation in yeast. FEBS J 2020; 288:3428-3447. [PMID: 33319437 DOI: 10.1111/febs.15670] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2020] [Revised: 11/07/2020] [Accepted: 12/11/2020] [Indexed: 12/22/2022]
Abstract
Precise control of protein and messenger RNA (mRNA) degradation is essential for cellular metabolism and homeostasis. Controlled and specific degradation of both molecular species necessitates their engagements with the respective degradation machineries; this engagement involves a disordered/unstructured segment of the substrate traversing the degradation tunnel of the machinery and accessing the catalytic sites. However, while molecular factors influencing protein degradation have been extensively explored on a genome scale, and in multiple organisms, such a comprehensive understanding remains missing for mRNAs. Here, we analyzed multiple genome-scale experimental yeast mRNA half-life data in light of experimentally derived mRNA secondary structures and protein binding data, along with high-resolution X-ray crystallographic structures of the RNase machines. Results unraveled a consistent genome-scale trend that mRNAs comprising longer terminal and/or internal unstructured segments have significantly shorter half-lives; the lengths of the 5'-terminal, 3'-terminal, and internal unstructured segments that affect mRNA half-life are compatible with molecular structures of the 5' exo-, 3' exo-, and endoribonuclease machineries. Sequestration into ribonucleoprotein complexes elongates mRNA half-life, presumably by burying ribonuclease engagement sites under oligomeric interfaces. After gene duplication, differences in terminal unstructured lengths, proportions of internal unstructured segments, and oligomerization modes result in significantly altered half-lives of paralogous mRNAs. Side-by-side comparison of molecular principles underlying controlled protein and mRNA degradation in yeast unravels their remarkable mechanistic similarities and suggests how the intrinsic structural features of the two molecular species, at two different levels of the central dogma, regulate their half-lives on genome scale.
Collapse
Affiliation(s)
- Sudipto Basu
- Department of Biophysics, Molecular Biology and Bioinformatics, University of Calcutta, Kolkata, India.,Center of Excellence in Systems Biology and Biomedical Engineering (TEQIP Phase-III), University of Calcutta, Kolkata, India
| | - Saurav Mallik
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Suman Hait
- Department of Biophysics, Molecular Biology and Bioinformatics, University of Calcutta, Kolkata, India
| | - Sudip Kundu
- Department of Biophysics, Molecular Biology and Bioinformatics, University of Calcutta, Kolkata, India.,Center of Excellence in Systems Biology and Biomedical Engineering (TEQIP Phase-III), University of Calcutta, Kolkata, India
| |
Collapse
|
15
|
Bathke J, Gauernack AS, Rupp O, Weber L, Preusser C, Lechner M, Rossbach O, Goesmann A, Evguenieva-Hackenberg E, Klug G. iCLIP analysis of RNA substrates of the archaeal exosome. BMC Genomics 2020; 21:797. [PMID: 33198623 PMCID: PMC7667871 DOI: 10.1186/s12864-020-07200-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Accepted: 10/27/2020] [Indexed: 12/25/2022] Open
Abstract
Background The archaeal exosome is an exoribonucleolytic multiprotein complex, which degrades single-stranded RNA in 3′ to 5′ direction phosphorolytically. In a reverse reaction, it can add A-rich tails to the 3′-end of RNA. The catalytic center of the exosome is in the aRrp41 subunit of its hexameric core. Its RNA-binding subunits aRrp4 and aDnaG confer poly(A) preference to the complex. The archaeal exosome was intensely characterized in vitro, but still little is known about its interaction with natural substrates in the cell, particularly because analysis of the transcriptome-wide interaction of an exoribonuclease with RNA is challenging. Results To determine binding sites of the exosome to RNA on a global scale, we performed individual-nucleotide resolution UV crosslinking and immunoprecipitation (iCLIP) analysis with antibodies directed against aRrp4 and aRrp41 of the chrenarchaeon Sulfolobus solfataricus. A relatively high proportion (17–19%) of the obtained cDNA reads could not be mapped to the genome. Instead, they corresponded to adenine-rich RNA tails, which are post-transcriptionally synthesized by the exosome, and to circular RNAs (circRNAs). We identified novel circRNAs corresponding to 5′ parts of two homologous, transposase-related mRNAs. To detect preferred substrates of the exosome, the iCLIP reads were compared to the transcript abundance using RNA-Seq data. Among the strongly enriched exosome substrates were RNAs antisense to tRNAs, overlapping 3′-UTRs and RNAs containing poly(A) stretches. The majority of the read counts and crosslink sites mapped in mRNAs. Furthermore, unexpected crosslink sites clustering at 5′-ends of RNAs was detected. Conclusions In this study, RNA targets of an exoribonuclease were analyzed by iCLIP. The data documents the role of the archaeal exosome as an exoribonuclease and RNA-tailing enzyme interacting with all RNA classes, and underlines its role in mRNA turnover, which is important for adaptation of prokaryotic cells to changing environmental conditions. The clustering of crosslink sites near 5′-ends of genes suggests simultaneous binding of both RNA ends by the S. solfataricus exosome. This may serve to prevent translation of mRNAs dedicated to degradation in 3′-5′ direction. Supplementary Information The online version contains supplementary material available at 10.1186/s12864-020-07200-x.
Collapse
Affiliation(s)
- Jochen Bathke
- Institute of Microbiology and Molecular Biology, Justus-Liebig-University, 35392, Giessen, Germany.,Institute of Bioinformatics and Systems Biology, Justus-Liebig-University, 35392, Giessen, Germany
| | - A Susann Gauernack
- Institute of Microbiology and Molecular Biology, Justus-Liebig-University, 35392, Giessen, Germany
| | - Oliver Rupp
- Institute of Bioinformatics and Systems Biology, Justus-Liebig-University, 35392, Giessen, Germany
| | - Lennart Weber
- Institute of Microbiology and Molecular Biology, Justus-Liebig-University, 35392, Giessen, Germany
| | - Christian Preusser
- Institute of Biochemistry, Justus-Liebig-University, 35392, Giessen, Germany
| | - Marcus Lechner
- Center for Synthetic Microbiology & Department of Pharmaceutical Chemistry, Philipps-University Marburg, 35032, Marburg, Germany
| | - Oliver Rossbach
- Institute of Biochemistry, Justus-Liebig-University, 35392, Giessen, Germany
| | - Alexander Goesmann
- Institute of Bioinformatics and Systems Biology, Justus-Liebig-University, 35392, Giessen, Germany
| | | | - Gabriele Klug
- Institute of Microbiology and Molecular Biology, Justus-Liebig-University, 35392, Giessen, Germany
| |
Collapse
|
16
|
Hernández RB, Carrascal M, Abian J, Michalke B, Farina M, Gonzalez YR, Iyirhiaro GO, Moteshareie H, Burnside D, Golshani A, Suñol C. Manganese-induced neurotoxicity in cerebellar granule neurons due to perturbation of cell network pathways with potential implications for neurodegenerative disorders. Metallomics 2020; 12:1656-1678. [PMID: 33206086 DOI: 10.1039/d0mt00085j] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Manganese (Mn) is essential for living organisms, playing an important role in nervous system function. Nevertheless, chronic and/or acute exposure to this metal, especially during early life stages, can lead to neurotoxicity and dementia by unclear mechanisms. Thus, based on previous works of our group with yeast and zebrafish, we hypothesized that the mechanisms mediating manganese-induced neurotoxicity can be associated with the alteration of protein metabolism. These mechanisms may also depend on the chemical speciation of manganese. Therefore, the current study aimed at investigating the mechanisms mediating the toxic effects of manganese in primary cultures of cerebellar granule neurons (CGNs). By exposing cultured CGNs to different chemical species of manganese ([[2-[(dithiocarboxy)amino]ethyl]carbamodithioato]](2-)-kS,kS']manganese, named maneb (MB), and [[1,2-ethanediylbis[carbamodithioato]](2-)]manganese mixture with [[1,2-ethanediylbis[carbamodithioato]](2-)]zinc, named mancozeb (MZ), and manganese chloride (MnCl2)), and using the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay, we observed that both MB and MZ induced similar cytotoxicity (LC50∼ 7-9 μM), which was higher than that of MnCl2 (LC50∼ 27 μM). Subsequently, we applied systems biology approaches, including metallomics, proteomics, gene expression and bioinformatics, and revealed that independent of chemical speciation, for non-cytotoxic concentrations (0.3-3 μM), Mn-induced neurotoxicity in CGNs is associated with metal dyshomeostasis and impaired protein metabolism. In this way, we verified that MB induced more post-translational alterations than MnCl2, which can be a plausible explanation for cytotoxic differences between both chemical species. The metabolism of proteins is one of the most energy consuming cellular processes and its impairment appears to be a key event of some cellular stress processes reported separately in other studies such as cell cycle arrest, energy impairment, cell signaling, excitotoxicity, immune response, potential protein accumulation and apoptosis. Interestingly, we verified that Mn-induced neurotoxicity shares pathways associated with the development of Alzheimer's disease, Amyotrophic Lateral Sclerosis, Huntington's disease, and Parkinson's disease. This has been observed in baker's yeast and zebrafish suggesting that the mode of action of Mn may be evolutionarily conserved.
Collapse
Affiliation(s)
- Raúl Bonne Hernández
- Laboratory of Bioinorganic and Environmental Toxicology - LABITA, Department of Exact and Earth Sciences, Federal University of São Paulo, Rua Prof. Artur Riedel, 275, CEP 09972-270, Diadema, SP, Brazil.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
17
|
Lan P, Zhou B, Tan M, Li S, Cao M, Wu J, Lei M. Structural insight into precursor ribosomal RNA processing by ribonuclease MRP. Science 2020; 369:656-663. [PMID: 32586950 DOI: 10.1126/science.abc0149] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Accepted: 06/11/2020] [Indexed: 12/16/2022]
Abstract
Ribonuclease (RNase) MRP is a conserved eukaryotic ribonucleoprotein complex that plays essential roles in precursor ribosomal RNA (pre-rRNA) processing and cell cycle regulation. In contrast to RNase P, which selectively cleaves transfer RNA-like substrates, it has remained a mystery how RNase MRP recognizes its diverse substrates. To address this question, we determined cryo-electron microscopy structures of Saccharomyces cerevisiae RNase MRP alone and in complex with a fragment of pre-rRNA. These structures and the results of biochemical studies reveal that coevolution of both protein and RNA subunits has transformed RNase MRP into a distinct ribonuclease that processes single-stranded RNAs by recognizing a short, loosely defined consensus sequence. This broad substrate specificity suggests that RNase MRP may have myriad yet unrecognized substrates that could play important roles in various cellular contexts.
Collapse
Affiliation(s)
- Pengfei Lan
- State Key Laboratory of Oncogenes and Related Genes, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200011, China.,Shanghai Institute of Precision Medicine, Shanghai 200125, China
| | - Bin Zhou
- State Key Laboratory of Oncogenes and Related Genes, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200011, China.,Shanghai Institute of Precision Medicine, Shanghai 200125, China
| | - Ming Tan
- State Key Laboratory of Oncogenes and Related Genes, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200011, China.,Shanghai Institute of Precision Medicine, Shanghai 200125, China
| | - Shaobai Li
- State Key Laboratory of Oncogenes and Related Genes, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200011, China.,Shanghai Institute of Precision Medicine, Shanghai 200125, China
| | - Mi Cao
- State Key Laboratory of Oncogenes and Related Genes, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200011, China.,Shanghai Institute of Precision Medicine, Shanghai 200125, China
| | - Jian Wu
- State Key Laboratory of Oncogenes and Related Genes, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200011, China. .,Shanghai Institute of Precision Medicine, Shanghai 200125, China
| | - Ming Lei
- State Key Laboratory of Oncogenes and Related Genes, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200011, China. .,Shanghai Institute of Precision Medicine, Shanghai 200125, China.,Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| |
Collapse
|
18
|
Lingaraju M, Schuller JM, Falk S, Gerlach P, Bonneau F, Basquin J, Benda C, Conti E. To Process or to Decay: A Mechanistic View of the Nuclear RNA Exosome. COLD SPRING HARBOR SYMPOSIA ON QUANTITATIVE BIOLOGY 2020; 84:155-163. [PMID: 32493762 DOI: 10.1101/sqb.2019.84.040295] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The RNA exosome was originally discovered in yeast as an RNA-processing complex required for the maturation of 5.8S ribosomal RNA (rRNA), one of the constituents of the large ribosomal subunit. The exosome is now known in eukaryotes as the major 3'-5' RNA degradation machine involved in numerous processing, turnover, and surveillance pathways, both in the nucleus and the cytoplasm. Yet its role in maturing the 5.8S rRNA in the pre-60S ribosomal particle remains probably the most intricate and emblematic among its functions, as it involves all the RNA unwinding, degradation, and trimming activities embedded in this macromolecular complex. Here, we propose a comprehensive mechanistic model, based on current biochemical and structural data, explaining the dual functions of the nuclear exosome-the constructive versus the destructive mode.
Collapse
Affiliation(s)
- Mahesh Lingaraju
- Max-Planck-Institute of Biochemistry, Department of Structural Cell Biology, D-82152 Martinsried/Munich, Germany
| | - Jan M Schuller
- Max-Planck-Institute of Biochemistry, Department of Structural Cell Biology, D-82152 Martinsried/Munich, Germany
| | - Sebastian Falk
- Max Perutz Labs, Department of Structural and Computational Biology, University of Vienna, 1030, Vienna, Austria
| | - Piotr Gerlach
- Max-Planck-Institute of Biochemistry, Department of Structural Cell Biology, D-82152 Martinsried/Munich, Germany
| | - Fabien Bonneau
- Max-Planck-Institute of Biochemistry, Department of Structural Cell Biology, D-82152 Martinsried/Munich, Germany
| | - Jérôme Basquin
- Max-Planck-Institute of Biochemistry, Department of Structural Cell Biology, D-82152 Martinsried/Munich, Germany
| | - Christian Benda
- Max-Planck-Institute of Biochemistry, Department of Structural Cell Biology, D-82152 Martinsried/Munich, Germany
| | - Elena Conti
- Max-Planck-Institute of Biochemistry, Department of Structural Cell Biology, D-82152 Martinsried/Munich, Germany
| |
Collapse
|
19
|
Insights into the assembly and architecture of a Staufen-mediated mRNA decay (SMD)-competent mRNP. Nat Commun 2019; 10:5054. [PMID: 31699982 PMCID: PMC6838198 DOI: 10.1038/s41467-019-13080-x] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2019] [Accepted: 10/18/2019] [Indexed: 02/07/2023] Open
Abstract
The mammalian Staufen proteins (Stau1 and Stau2) mediate degradation of mRNA containing complex secondary structures in their 3’-untranslated region (UTR) through a pathway known as Staufen-mediated mRNA decay (SMD). This pathway also involves the RNA helicase UPF1, which is best known for its role in the nonsense-mediated mRNA decay (NMD) pathway. Here we present a biochemical reconstitution of the recruitment and activation of UPF1 in context of the SMD pathway. We demonstrate the involvement of UPF2, a core NMD factor and a known activator of UPF1, in SMD. UPF2 acts as an adaptor between Stau1 and UPF1, stimulates the catalytic activity of UPF1 and plays a central role in the formation of an SMD-competent mRNP. Our study elucidates the molecular mechanisms of SMD and points towards extensive cross-talk between UPF1-mediated mRNA decay pathways in cells. The Staufen proteins recognize secondary structures in 3’-untranslated regions in mRNA transcripts and induce degradation of these mRNAs with the help of the RNA helicase UPF1. Here the authors report that the nonsense-mediated mRNA decay factor UPF2 mediates the interaction between Stau1 and UPF1 in Staufen-mediated mRNA decay.
Collapse
|
20
|
Yang W, Xia Y, Qian X, Wang M, Zhang X, Li Y, Li L. Co-expression network analysis identified key genes in association with mesenchymal stem cell osteogenic differentiation. Cell Tissue Res 2019; 378:513-529. [PMID: 31418071 DOI: 10.1007/s00441-019-03071-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2018] [Accepted: 07/03/2019] [Indexed: 01/23/2023]
Abstract
Although several studies have shown that osteogenic differentiation of different mesenchymal stem cell (MSC) lines can be guided by the 3D scaffold with growth factors or biochemical agent, the key mechanism regulating osteogenic differentiation is not known yet. Here, this study was designed to investigate key genes that regulate the induction of osteogenesis by different MSC lines in different ways. Expression profiling by array (GSE58919 and GSE18043) was downloaded and analyzed using weighted gene co-expression network analysis (WGCNA) to narrow genes associated with osteogenic differentiation. A protein-protein interactive (PPI) network was built to find the key genes and the role of these key genes was confirmed by statistical analysis. To understand the function of genes associated with osteogenesis, gene ontology (GO) and the Kyoto encyclopedia of genes and genomes (KEGG) were analyzed, which showed that key genes in MSC osteogenic differentiation induced by a biochemical agent involve regulation of cell apoptosis and proliferation while key genes in MSC osteogenic differentiation induced by the 3D scaffold with growth factors involve regulation of cajal body and centromeres. Furthermore, 58 key genes are involved in Wnt signaling pathway, ion response and focal adhesion. Proteasome also played a key role in osteogenic differentiation. Seven potential key genes were found essential in the osteogenic differentiation of MSCs in the PPI network, especially the five key genes, CCT2, NOP58, FBL, EXOSC8 and SNRPD1. This study will provide important targets of MSC osteogenic differentiation that will help us understand the mechanism of osteogenic differentiation in MSCs.
Collapse
Affiliation(s)
- Wang Yang
- The Key Laboratory of Pathobiology, Ministry of Education, Norman Bethune College of Medicine, Jilin University, Changchun, 130021, China.,College of Clinical Medicine, Jilin University, Changchun, China
| | - Yuhan Xia
- The Key Laboratory of Pathobiology, Ministry of Education, Norman Bethune College of Medicine, Jilin University, Changchun, 130021, China
| | - Xiaoli Qian
- The Key Laboratory of Pathobiology, Ministry of Education, Norman Bethune College of Medicine, Jilin University, Changchun, 130021, China
| | - Meijing Wang
- The Key Laboratory of Pathobiology, Ministry of Education, Norman Bethune College of Medicine, Jilin University, Changchun, 130021, China
| | - Xiaoling Zhang
- The First Hospital, Jilin University, Changchun, 130061, China. .,Institute of Immunology, Jilin University, Changchun, 130061, China.
| | - Yulin Li
- The Key Laboratory of Pathobiology, Ministry of Education, Norman Bethune College of Medicine, Jilin University, Changchun, 130021, China.
| | - Lisha Li
- The Key Laboratory of Pathobiology, Ministry of Education, Norman Bethune College of Medicine, Jilin University, Changchun, 130021, China.
| |
Collapse
|
21
|
Lingaraju M, Johnsen D, Schlundt A, Langer LM, Basquin J, Sattler M, Heick Jensen T, Falk S, Conti E. The MTR4 helicase recruits nuclear adaptors of the human RNA exosome using distinct arch-interacting motifs. Nat Commun 2019; 10:3393. [PMID: 31358741 PMCID: PMC6662825 DOI: 10.1038/s41467-019-11339-x] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2019] [Accepted: 07/07/2019] [Indexed: 12/16/2022] Open
Abstract
The nuclear exosome and its essential co-factor, the RNA helicase MTR4, play crucial roles in several RNA degradation pathways. Besides unwinding RNA substrates for exosome-mediated degradation, MTR4 associates with RNA-binding proteins that function as adaptors in different RNA processing and decay pathways. Here, we identify and characterize the interactions of human MTR4 with a ribosome processing adaptor, NVL, and with ZCCHC8, an adaptor involved in the decay of small nuclear RNAs. We show that the unstructured regions of NVL and ZCCHC8 contain short linear motifs that bind the MTR4 arch domain in a mutually exclusive manner. These short sequences diverged from the arch-interacting motif (AIM) of yeast rRNA processing factors. Our results suggest that nuclear exosome adaptors have evolved canonical and non-canonical AIM sequences to target human MTR4 and demonstrate the versatility and specificity with which the MTR4 arch domain can recruit a repertoire of different RNA-binding proteins.
Collapse
Affiliation(s)
- Mahesh Lingaraju
- Department of Structural Cell Biology, Max-Planck-Institute of Biochemistry, Am Klopferspitz 18, D-82152, Martinsried, Germany
| | - Dennis Johnsen
- Department of Molecular Biology and Genetics, Aarhus University, C.F. Møllers Alle 3, 8000, Aarhus C, Denmark
| | - Andreas Schlundt
- Center for Integrated Protein Science Munich (CIPSM) at Department of Chemistry, Technical University of Munich (TUM), 85747, Garching, Germany.,Institute of Structural Biology, Helmholtz-Zentrum München, 85764, Neuherberg, Germany.,Institute for Molecular Biosciences and Center for Biomolecular Magnetic Resonance (BMRZ) at Johann Wolfgang Goethe-University, Frankfurt am Main, 60438, Germany
| | - Lukas M Langer
- Department of Structural Cell Biology, Max-Planck-Institute of Biochemistry, Am Klopferspitz 18, D-82152, Martinsried, Germany
| | - Jérôme Basquin
- Department of Structural Cell Biology, Max-Planck-Institute of Biochemistry, Am Klopferspitz 18, D-82152, Martinsried, Germany
| | - Michael Sattler
- Center for Integrated Protein Science Munich (CIPSM) at Department of Chemistry, Technical University of Munich (TUM), 85747, Garching, Germany.,Institute of Structural Biology, Helmholtz-Zentrum München, 85764, Neuherberg, Germany
| | - Torben Heick Jensen
- Department of Molecular Biology and Genetics, Aarhus University, C.F. Møllers Alle 3, 8000, Aarhus C, Denmark
| | - Sebastian Falk
- Department of Structural Cell Biology, Max-Planck-Institute of Biochemistry, Am Klopferspitz 18, D-82152, Martinsried, Germany. .,Max F. Perutz Laboratories, Department of Structural and Computational Biology, University of Vienna, Campus Vienna Biocenter 5, 1030, Vienna, Austria.
| | - Elena Conti
- Department of Structural Cell Biology, Max-Planck-Institute of Biochemistry, Am Klopferspitz 18, D-82152, Martinsried, Germany.
| |
Collapse
|
22
|
Urdaneta EC, Vieira-Vieira CH, Hick T, Wessels HH, Figini D, Moschall R, Medenbach J, Ohler U, Granneman S, Selbach M, Beckmann BM. Purification of cross-linked RNA-protein complexes by phenol-toluol extraction. Nat Commun 2019; 10:990. [PMID: 30824702 PMCID: PMC6397201 DOI: 10.1038/s41467-019-08942-3] [Citation(s) in RCA: 140] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Accepted: 02/11/2019] [Indexed: 12/30/2022] Open
Abstract
Recent methodological advances allowed the identification of an increasing number of RNA-binding proteins (RBPs) and their RNA-binding sites. Most of those methods rely, however, on capturing proteins associated to polyadenylated RNAs which neglects RBPs bound to non-adenylate RNA classes (tRNA, rRNA, pre-mRNA) as well as the vast majority of species that lack poly-A tails in their mRNAs (including all archea and bacteria). We have developed the Phenol Toluol extraction (PTex) protocol that does not rely on a specific RNA sequence or motif for isolation of cross-linked ribonucleoproteins (RNPs), but rather purifies them based entirely on their physicochemical properties. PTex captures RBPs that bind to RNA as short as 30 nt, RNPs directly from animal tissue and can be used to simplify complex workflows such as PAR-CLIP. Finally, we provide a global RNA-bound proteome of human HEK293 cells and the bacterium Salmonella Typhimurium.
Collapse
Affiliation(s)
- Erika C Urdaneta
- IRI Life Sciences, Humboldt University, Philippstr. 13, 10115, Berlin, Germany
| | - Carlos H Vieira-Vieira
- Max-Delbrück-Center for Molecular Medicine, Robert-Rössle-Str. 10, 13125, Berlin, Germany
| | - Timon Hick
- IRI Life Sciences, Humboldt University, Philippstr. 13, 10115, Berlin, Germany
| | - Hans-Herrmann Wessels
- Berlin Institute for Medical Systems Biology, Max-Delbrück-Center for Molecular Medicine, Robert-Rössle-Str. 10, 13125, Berlin, Germany
- Department of Biology, Humboldt University, Philippstr. 13, 10115, Berlin, Germany
| | - Davide Figini
- IRI Life Sciences, Humboldt University, Philippstr. 13, 10115, Berlin, Germany
| | - Rebecca Moschall
- Biochemistry I, University of Regensburg, Universitätsstrasse 31, 93053, Regensburg, Germany
| | - Jan Medenbach
- Biochemistry I, University of Regensburg, Universitätsstrasse 31, 93053, Regensburg, Germany
| | - Uwe Ohler
- Berlin Institute for Medical Systems Biology, Max-Delbrück-Center for Molecular Medicine, Robert-Rössle-Str. 10, 13125, Berlin, Germany
- Department of Biology, Humboldt University, Philippstr. 13, 10115, Berlin, Germany
| | - Sander Granneman
- Centre for Systems and Synthetic Biology (SynthSys), University of Edinburgh, Max Born Crescent, Edinburgh, EH9 3BF, UK
| | - Matthias Selbach
- Max-Delbrück-Center for Molecular Medicine, Robert-Rössle-Str. 10, 13125, Berlin, Germany
| | - Benedikt M Beckmann
- IRI Life Sciences, Humboldt University, Philippstr. 13, 10115, Berlin, Germany.
| |
Collapse
|
23
|
Corbett AH. Post-transcriptional regulation of gene expression and human disease. Curr Opin Cell Biol 2018; 52:96-104. [PMID: 29518673 PMCID: PMC5988930 DOI: 10.1016/j.ceb.2018.02.011] [Citation(s) in RCA: 93] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Revised: 02/08/2018] [Accepted: 02/15/2018] [Indexed: 12/18/2022]
Abstract
A large number of mutations in genes that encode RNA binding proteins cause human disease. Many of these RNA binding proteins mediate key steps in post-transcriptional regulation of gene expression from mRNA processing to eventual decay in the cytoplasm. Surprisingly, these RNA binding proteins, which are ubiquitously expressed and play fundamental roles in gene expression, are often altered in tissue-specific disease. Mutations linked to disease impact nearly every post-transcriptional processing step and cause diverse disease phenotypes in a variety of specific tissues. This review summarizes steps in post-transcriptional regulation of gene expression that have been linked to disease providing specific examples of some of the many genes affected. Finally, recent advances that hold promise for treatment of some of these diseases are presented.
Collapse
Affiliation(s)
- Anita H Corbett
- Department of Biology, RRC 1021, Emory University, 1510 Clifton Road, NE, Atlanta 30322, GA, United States.
| |
Collapse
|
24
|
Mpp6 Incorporation in the Nuclear Exosome Contributes to RNA Channeling through the Mtr4 Helicase. Cell Rep 2018; 20:2279-2286. [PMID: 28877463 PMCID: PMC5603729 DOI: 10.1016/j.celrep.2017.08.033] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Revised: 07/27/2017] [Accepted: 08/11/2017] [Indexed: 12/24/2022] Open
Abstract
The RNA-degrading exosome mediates the processing and decay of many cellular transcripts. In the yeast nucleus, the ubiquitous 10-subunit exosome core complex (Exo-9–Rrp44) functions with four conserved cofactors (Rrp6, Rrp47, Mtr4, and Mpp6). Biochemical and structural studies to date have shed insights into the mechanisms of the exosome core and its nuclear cofactors, with the exception of Mpp6. We report the 3.2-Å resolution crystal structure of a S. cerevisiae Exo-9–Mpp6 complex, revealing how linear motifs in the Mpp6 middle domain bind Rrp40 via evolutionary conserved residues. In particular, Mpp6 binds near a tryptophan residue of Rrp40 that is mutated in human patients suffering from pontocerebellar hypoplasia. Using biochemical assays, we show that Mpp6 is required for the ability of Mtr4 to extend the trajectory of an RNA entering the exosome core, suggesting that it promotes the channeling of substrates from the nuclear helicase to the processive RNase. Yeast Mpp6 is stably bound to the nuclear exosome core both in vivo and in vitro The Mpp6 middle domain binds the Rrp40 exosome subunit with conserved interactions Mpp6 enhances the ability of the Mtr4 helicase to channel RNA into the exosome core The pontocerebellar W238R mutation in human EXOSC3 affects the hMPP6-binding site
Collapse
|
25
|
Ren J, He W, Zheng L, Duan H. From structures to functions: insights into exosomes as promising drug delivery vehicles. Biomater Sci 2018; 4:910-21. [PMID: 26977477 DOI: 10.1039/c5bm00583c] [Citation(s) in RCA: 94] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Exosomes are small membrane vesicles secreted by most cell types, and appear ubiquitously in cell culture supernatants and body fluids. Increasing evidence supports that exosomes play important roles in intercellular communication, both locally and systemically, by transporting their contents such as proteins, lipids and RNAs between cells. Of particular interest for controlled drug delivery is that cell-derived exosomes offer the possibilities of overcoming biological barriers, thereby allowing the incorporated gene and drug to reach targeted tissue, which have been considerable challenges for synthetic carriers. Great research efforts have been dedicated to developing exosome-based drug delivery systems for the treatment of inflammatory diseases, degenerative disorders and cancer. In this review, we will describe the structural and functional properties of exosomes and emphasize current advances in the therapeutic applications of exosomes as drug delivery vehicles, followed by a discussion on current challenges and future perspectives.
Collapse
Affiliation(s)
- Jinghua Ren
- Cancer Center, Union Hospital, Tongji Medical College, Huazhong University of Science & Technology, Wuhan 430022, P. R. China.
| | - Wenshan He
- Department of Breast and Thyroid Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science & Technology, Wuhan 430022, P. R. China
| | - Lifen Zheng
- Cancer Center, Union Hospital, Tongji Medical College, Huazhong University of Science & Technology, Wuhan 430022, P. R. China.
| | - Hongwei Duan
- School of Chemical and Biomedical Engineering, Nanyang Technological University, 70 Nanyang Drive, 637457 Singapore.
| |
Collapse
|
26
|
Schuller JM, Falk S, Fromm L, Hurt E, Conti E. Structure of the nuclear exosome captured on a maturing preribosome. Science 2018. [PMID: 29519915 DOI: 10.1126/science.aar5428] [Citation(s) in RCA: 98] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The RNA exosome complex processes and degrades a wide range of transcripts, including ribosomal RNAs (rRNAs). We used cryo-electron microscopy to visualize the yeast nuclear exosome holocomplex captured on a precursor large ribosomal subunit (pre-60S) during 7S-to-5.8S rRNA processing. The cofactors of the nuclear exosome are sandwiched between the ribonuclease core complex (Exo-10) and the remodeled "foot" structure of the pre-60S particle, which harbors the 5.8S rRNA precursor. The exosome-associated helicase Mtr4 recognizes the preribosomal substrate by docking to specific sites on the 25S rRNA, captures the 3' extension of the 5.8S rRNA, and channels it toward Exo-10. The structure elucidates how the exosome forms a structural and functional unit together with its massive pre-60S substrate to process rRNA during ribosome maturation.
Collapse
Affiliation(s)
- Jan Michael Schuller
- Department of Structural Cell Biology, Max Planck Institute (MPI) for Biochemistry, Munich, Germany
| | - Sebastian Falk
- Department of Structural Cell Biology, Max Planck Institute (MPI) for Biochemistry, Munich, Germany
| | - Lisa Fromm
- Biochemistry Centre, University of Heidelberg, Heidelberg, Germany
| | - Ed Hurt
- Biochemistry Centre, University of Heidelberg, Heidelberg, Germany.
| | - Elena Conti
- Department of Structural Cell Biology, Max Planck Institute (MPI) for Biochemistry, Munich, Germany.
| |
Collapse
|
27
|
Han J, van Hoof A. The RNA Exosome Channeling and Direct Access Conformations Have Distinct In Vivo Functions. Cell Rep 2018; 16:3348-3358. [PMID: 27653695 DOI: 10.1016/j.celrep.2016.08.059] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Revised: 06/06/2016] [Accepted: 08/18/2016] [Indexed: 10/21/2022] Open
Abstract
The RNA exosome is a 3'-5' ribonuclease complex that is composed of nine core subunits and an essential catalytic subunit, Rrp44. Two distinct conformations of Rrp44 were revealed in previous structural studies, suggesting that Rrp44 may change its conformation to exert its function. In the channeling conformation, (Rrp44(ch)), RNA accesses the active site after traversing the central channel of the RNA exosome, whereas in the other conformation, (Rrp44(da)), RNA gains direct access to the active site. Here, we show that the Rrp44(da) exosome is important for nuclear function of the RNA exosome. Defects caused by disrupting the direct access conformation are distinct from those caused by channel-occluding mutations, indicating specific functions for each conformation. Our genetic analyses provide in vivo evidence that the RNA exosome employs a direct-access route to recruit specific substrates, indicating that the RNA exosome uses alternative conformations to act on different RNA substrates.
Collapse
Affiliation(s)
- Jaeil Han
- Department of Microbiology and Molecular Genetics, University of Texas Health Science Center at Houston, 6431 Fannin Street, MSB 1.212, Houston, TX 77030, USA; The University of Texas Graduate School of Biomedical Sciences, University of Texas Health Science Center at Houston, 6431 Fannin Street, MSB 1.212, Houston, TX 77030, USA
| | - Ambro van Hoof
- Department of Microbiology and Molecular Genetics, University of Texas Health Science Center at Houston, 6431 Fannin Street, MSB 1.212, Houston, TX 77030, USA; The University of Texas Graduate School of Biomedical Sciences, University of Texas Health Science Center at Houston, 6431 Fannin Street, MSB 1.212, Houston, TX 77030, USA.
| |
Collapse
|
28
|
Sikorska N, Zuber H, Gobert A, Lange H, Gagliardi D. RNA degradation by the plant RNA exosome involves both phosphorolytic and hydrolytic activities. Nat Commun 2017; 8:2162. [PMID: 29255150 PMCID: PMC5735172 DOI: 10.1038/s41467-017-02066-2] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2017] [Accepted: 11/03/2017] [Indexed: 12/21/2022] Open
Abstract
The RNA exosome provides eukaryotic cells with an essential 3'-5' exoribonucleolytic activity, which processes or eliminates many classes of RNAs. Its nine-subunit core (Exo9) is structurally related to prokaryotic phosphorolytic exoribonucleases. Yet, yeast and animal Exo9s have lost the primordial phosphorolytic capacity and rely instead on associated hydrolytic ribonucleases for catalytic activity. Here, we demonstrate that Arabidopsis Exo9 has retained a distributive phosphorolytic activity, which contributes to rRNA maturation processes, the hallmark of exosome function. High-density mapping of 3' extremities of rRNA maturation intermediates reveals the intricate interplay between three exoribonucleolytic activities coordinated by the plant exosome. Interestingly, the analysis of RRP41 protein diversity across eukaryotes suggests that Exo9's intrinsic activity operates throughout the green lineage, and possibly in some earlier-branching non-plant eukaryotes. Our results reveal a remarkable evolutionary variation of this essential RNA degradation machine in eukaryotes.
Collapse
Affiliation(s)
- Natalia Sikorska
- IBMP, CNRS, University of Strasbourg, 12 rue du général Zimmer, 67000, Strasbourg, France
| | - Hélène Zuber
- IBMP, CNRS, University of Strasbourg, 12 rue du général Zimmer, 67000, Strasbourg, France
| | - Anthony Gobert
- IBMP, CNRS, University of Strasbourg, 12 rue du général Zimmer, 67000, Strasbourg, France
| | - Heike Lange
- IBMP, CNRS, University of Strasbourg, 12 rue du général Zimmer, 67000, Strasbourg, France
| | - Dominique Gagliardi
- IBMP, CNRS, University of Strasbourg, 12 rue du général Zimmer, 67000, Strasbourg, France.
| |
Collapse
|
29
|
Falk S, Tants JN, Basquin J, Thoms M, Hurt E, Sattler M, Conti E. Structural insights into the interaction of the nuclear exosome helicase Mtr4 with the preribosomal protein Nop53. RNA (NEW YORK, N.Y.) 2017; 23:1780-1787. [PMID: 28883156 PMCID: PMC5688999 DOI: 10.1261/rna.062901.117] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2017] [Accepted: 09/05/2017] [Indexed: 05/24/2023]
Abstract
The nuclear exosome and the associated RNA helicase Mtr4 participate in the processing of several ribonucleoprotein particles (RNP), including the maturation of the large ribosomal subunit (60S). S. cerevisiae Mtr4 interacts directly with Nop53, a ribosomal biogenesis factor present in late pre-60S particles containing precursors of the 5.8S rRNA. The Mtr4-Nop53 interaction plays a pivotal role in the maturation of the 5.8S rRNA, providing a physical link between the nuclear exosome and the pre-60S RNP. An analogous interaction between Mtr4 and another ribosome biogenesis factor, Utp18, directs the exosome to an earlier preribosomal particle. Nop53 and Utp18 contain a similar Mtr4-binding motif known as the arch-interacting motif (AIM). Here, we report the 3.2 Å resolution crystal structure of S. cerevisiae Mtr4 bound to the interacting region of Nop53, revealing how the KOW domain of the helicase recognizes the AIM sequence of Nop53 with a network of hydrophobic and electrostatic interactions. The AIM-interacting residues are conserved in Mtr4 and are not present in the related cytoplasmic helicase Ski2, rationalizing the specificity and versatility of Mtr4 in the recognition of different AIM-containing proteins. Using nuclear magnetic resonance (NMR), we show that the KOW domain of Mtr4 can simultaneously bind an AIM-containing protein and a structured RNA at adjacent surfaces, suggesting how it can dock onto RNPs. The KOW domains of exosome-associated helicases thus appear to have evolved from the KOW domains of ribosomal proteins and to function as RNP-binding modules in the context of the nuclear exosome.
Collapse
Affiliation(s)
- Sebastian Falk
- Max-Planck-Institute of Biochemistry, Department of Structural Cell Biology, D-82152 Martinsried, Germany
| | - Jan-Niklas Tants
- Center for Integrated Protein Science Munich at Chair of Biomolecular NMR Spectroscopy, Department Chemie, Technische Universität München, 85748 Garching, Germany
- Institute of Structural Biology, Helmholtz Zentrum München, 85764 Neuherberg, Germany
| | - Jerôme Basquin
- Max-Planck-Institute of Biochemistry, Department of Structural Cell Biology, D-82152 Martinsried, Germany
| | - Matthias Thoms
- Heidelberg University Biochemistry Center (BZH), INF 328, D-69120 Heidelberg, Germany
| | - Ed Hurt
- Heidelberg University Biochemistry Center (BZH), INF 328, D-69120 Heidelberg, Germany
| | - Michael Sattler
- Center for Integrated Protein Science Munich at Chair of Biomolecular NMR Spectroscopy, Department Chemie, Technische Universität München, 85748 Garching, Germany
- Institute of Structural Biology, Helmholtz Zentrum München, 85764 Neuherberg, Germany
| | - Elena Conti
- Max-Planck-Institute of Biochemistry, Department of Structural Cell Biology, D-82152 Martinsried, Germany
| |
Collapse
|
30
|
Silva S, Homolka D, Pillai RS. Characterization of the mammalian RNA exonuclease 5/NEF-sp as a testis-specific nuclear 3' → 5' exoribonuclease. RNA (NEW YORK, N.Y.) 2017; 23:1385-1392. [PMID: 28539487 PMCID: PMC5558908 DOI: 10.1261/rna.060723.117] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Accepted: 05/22/2017] [Indexed: 06/07/2023]
Abstract
Ribonucleases catalyze maturation of functional RNAs or mediate degradation of cellular transcripts, activities that are critical for gene expression control. Here we identify a previously uncharacterized mammalian nuclease family member NEF-sp (RNA exonuclease 5 [REXO5] or LOC81691) as a testis-specific factor. Recombinant human NEF-sp demonstrates a divalent metal ion-dependent 3' → 5' exoribonuclease activity. This activity is specific to single-stranded RNA substrates and is independent of their length. The presence of a 2'-O-methyl modification at the 3' end of the RNA substrate is inhibitory. Ectopically expressed NEF-sp localizes to the nucleolar/nuclear compartment in mammalian cell cultures and this is dependent on an amino-terminal nuclear localization signal. Finally, mice lacking NEF-sp are viable and display normal fertility, likely indicating overlapping functions with other nucleases. Taken together, our study provides the first biochemical and genetic exploration of the role of the NEF-sp exoribonuclease in the mammalian genome.
Collapse
Affiliation(s)
- Sara Silva
- Department of Molecular Biology, University of Geneva, CH-1211 Geneva 4, Switzerland
- European Molecular Biology Laboratory, Grenoble Outstation, 38042, France
| | - David Homolka
- Department of Molecular Biology, University of Geneva, CH-1211 Geneva 4, Switzerland
| | - Ramesh S Pillai
- Department of Molecular Biology, University of Geneva, CH-1211 Geneva 4, Switzerland
| |
Collapse
|
31
|
Schmidt O, Weyer Y, Fink MJ, Müller M, Weys S, Bindreither M, Teis D. Regulation of Rab5 isoforms by transcriptional and post-transcriptional mechanisms in yeast. FEBS Lett 2017; 591:2803-2815. [PMID: 28792590 PMCID: PMC5637908 DOI: 10.1002/1873-3468.12785] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2017] [Revised: 07/26/2017] [Accepted: 07/31/2017] [Indexed: 12/15/2022]
Abstract
Rab5 GTPases are master regulators of early endosome biogenesis and transport. The genome of Saccharomyces cerevisiae encodes three Rab5 proteins: Vps21, the major isoform, Ypt52 and Ypt53. Here, we show that Vps21 is the most abundant Rab5 protein and Ypt53 is the least abundant. In stressed cells, Ypt53 levels increase but never exceed that of Vps21. Its induction requires the transcription factors Crz1 and Gis1. In growing cells, the expression of Ypt53 is suppressed by post-transcriptional mechanisms mediated by the untranslated regions of the YPT53 mRNA. Based on genetic experiments, these sequences appear to stimulate deadenylation, Pat1-activated decapping and Xrn1-mediated mRNA degradation. Once this regulation is bypassed, Ypt53 protein levels surpass Vps21, and Ypt53 is sufficient to maintain endosomal function and cell growth.
Collapse
Affiliation(s)
- Oliver Schmidt
- Division of Cell Biology, Biocenter, Medical University of Innsbruck, Austria
| | - Yannick Weyer
- Division of Cell Biology, Biocenter, Medical University of Innsbruck, Austria
| | - Matthias J Fink
- Division of Cell Biology, Biocenter, Medical University of Innsbruck, Austria
| | - Martin Müller
- Division of Cell Biology, Biocenter, Medical University of Innsbruck, Austria
| | - Sabine Weys
- Division of Cell Biology, Biocenter, Medical University of Innsbruck, Austria
| | | | - David Teis
- Division of Cell Biology, Biocenter, Medical University of Innsbruck, Austria
| |
Collapse
|
32
|
Lu M, Xing H, Yang Z, Sun Y, Yang T, Zhao X, Cai C, Wang D, Ding P. Recent advances on extracellular vesicles in therapeutic delivery: Challenges, solutions, and opportunities. Eur J Pharm Biopharm 2017; 119:381-395. [PMID: 28739288 DOI: 10.1016/j.ejpb.2017.07.010] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2017] [Revised: 06/24/2017] [Accepted: 07/20/2017] [Indexed: 12/21/2022]
Abstract
Extracellular vesicles (EVs) are intrinsic mediators of intercellular communication in our body, allowing functional transfer of biomolecules (lipids, proteins, and nucleic acid) between diverse locations. Such an instrumental role evokes a surge of interest within the drug delivery community in tailoring EVs for therapeutic delivery. These vesicles represent a novel generation of drug delivery systems, providing high delivery efficiency, intrinsic targeting properties, and low immunogenicity. In the recent years, considerable research efforts have been directed toward developing safe and efficient EV-based delivery vehicles. Although EVs are shown to harbor great promise in therapeutic delivery, substantial improvements in exploring standardized isolation techniques with high efficiency and robust yield, scalable production, standard procedures for EV storage, efficient loading methods without damaging EV integrity, understanding their in vivo trafficking, and developing novel EV-based nanocarriers are still required before their clinical transformation. In this review, we seek to summarize the recent advance on harnessing EVs for drug delivery with focus on state-of-the-art solutions for overcoming major challenges.
Collapse
Affiliation(s)
- Mei Lu
- School of Pharmacy, Shenyang Pharmaceutical University, Shenyang, China
| | - Haonan Xing
- School of Pharmacy, Shenyang Pharmaceutical University, Shenyang, China
| | - Zhen Yang
- School of Pharmacy, Shenyang Pharmaceutical University, Shenyang, China
| | - Yanping Sun
- School of Pharmacy, Shenyang Pharmaceutical University, Shenyang, China
| | - Tianzhi Yang
- Department of Basic Pharmaceutical Sciences, School of Pharmacy, Husson University, Bangor, ME, USA
| | - Xiaoyun Zhao
- School of Life Science and Biopharmaceutics, Shenyang Pharmaceutical University, Shenyang, China
| | - Cuifang Cai
- School of Pharmacy, Shenyang Pharmaceutical University, Shenyang, China
| | - Dongkai Wang
- School of Pharmacy, Shenyang Pharmaceutical University, Shenyang, China.
| | - Pingtian Ding
- School of Pharmacy, Shenyang Pharmaceutical University, Shenyang, China.
| |
Collapse
|
33
|
Abstract
Constitutive and regulated turnover of RNAs is necessary to eliminate aberrant RNA molecules and control the level of specific mRNAs to maintain homeostasis or to respond to signals in living cells. Modifications of nucleosides in specific RNAs are important in modulating the functions of these transcripts, but they can also dramatically impact their fate and turnover. This chapter will review how RNA modifications impact the activities of ribonucleases that target these RNAs for degradation or cleavage, focusing more particularly on tRNAs and mRNAs in eukaryotic cells. Many nucleoside modifications are important to promote proper folding of tRNAs, and the absence of specific modifications makes them susceptible to degradation by quality control pathways that eliminate improperly folded species. Modifications in tRNAs can also modulate their cleavage during stress or by fungal toxins that target modified nucleosides. Modifications of the cap structure found at the 5'-end of eukaryotic mRNAs are essential to control the degradation of these mRNAs. In addition, internal modifications of eukaryotic mRNAs can change their secondary structures or provide binding sites for reader proteins, which can dramatically impact their stability. Recent examples show that mRNA modifications play important roles in regulating mRNA stability during development, cellular differentiation and physiological responses. Finally, many modifications can impact microRNA- and siRNA-mediated gene regulation by direct or indirect effects. With the growing number of genomic techniques able to identify modifications genome wide, it is anticipated that novel chemical modifications or new modification sites will be identified, which will play additional regulatory functions for RNA turnover.
Collapse
|
34
|
Chierico L, Rizzello L, Guan L, Joseph AS, Lewis A, Battaglia G. The role of the two splice variants and extranuclear pathway on Ki-67 regulation in non-cancer and cancer cells. PLoS One 2017; 12:e0171815. [PMID: 28187152 PMCID: PMC5302784 DOI: 10.1371/journal.pone.0171815] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2016] [Accepted: 01/26/2017] [Indexed: 12/28/2022] Open
Abstract
Ki-67 is a nuclear protein that has been used in cancer diagnostic because of its specific cell-cycle dependent expression profile. After quantifying and characterising the expression level of Ki-67, as a function of the cell cycle, we found out that the two main splice variants of the protein (i.e. α and β) are differently regulated in non-cancerous and cancerous cells both at mRNA and protein level. We were able to correlate the presence of the α variant of the protein with the progression through the interphase of cell cycle. We also observed that the different expression profiles correspond to different degradation pathways for non-cancerous and cancerous cells. Furthermore, Ki-67 is continuously regulated and degraded via proteasome system in both cell types, suggesting an active control of the protein. However we also observed a putative extranuclear elimination pathway of Ki-67 where it is transported to the Golgi apparatus. Our evidence in the different expression of the splice variants may represent a milestone for the development of new targets for cancer diagnostic and prognostic. Additionally, the unexpected extranuclear elimination of Ki-67 strongly suggests that this protein must be looked at also outside of the "nuclear box", as thought to date.
Collapse
Affiliation(s)
- Luca Chierico
- Department of Chemistry, University College London, London, United Kingdom
| | - Loris Rizzello
- Department of Chemistry, University College London, London, United Kingdom
| | - Lijuan Guan
- Department of Chemistry, University College London, London, United Kingdom
| | | | - Andrew Lewis
- Biocompatibles UK Ltd., Farnham Business Park, Weydon Lane, Farnham, United Kingdom
| | - Giuseppe Battaglia
- Department of Chemistry, University College London, London, United Kingdom
| |
Collapse
|
35
|
Falk S, Finogenova K, Melko M, Benda C, Lykke-Andersen S, Jensen TH, Conti E. Structure of the RBM7-ZCCHC8 core of the NEXT complex reveals connections to splicing factors. Nat Commun 2016; 7:13573. [PMID: 27905398 PMCID: PMC5146272 DOI: 10.1038/ncomms13573] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Accepted: 10/13/2016] [Indexed: 01/24/2023] Open
Abstract
The eukaryotic RNA exosome participates extensively in RNA processing and degradation. In human cells, three accessory factors (RBM7, ZCCHC8 and hMTR4) interact to form the nuclear exosome targeting (NEXT) complex, which directs a subset of non-coding RNAs for exosomal degradation. Here we elucidate how RBM7 is incorporated in the NEXT complex. We identify a proline-rich segment of ZCCHC8 as the interaction site for the RNA-recognition motif (RRM) of RBM7 and present the crystal structure of the corresponding complex at 2.0 Å resolution. On the basis of the structure, we identify a proline-rich segment within the splicing factor SAP145 with strong similarity to ZCCHC8. We show that this segment of SAP145 not only binds the RRM region of another splicing factor SAP49 but also the RRM of RBM7. These dual interactions of RBM7 with the exosome and the spliceosome suggest a model whereby NEXT might recruit the exosome to degrade intronic RNAs. RBM7 and ZCCHC8 are two core subunits of the Nuclear Exosome Targeting complex, which regulates the degradation of selected non-coding RNAs in human cells. Here, the authors use structural and biochemical methods to show how ZCCHC8 recruits RBM7 in the complex, leaving the RNA binding site accessible and revealing possible implications for splicing.
Collapse
Affiliation(s)
- Sebastian Falk
- Department of Structural Cell Biology, Max-Planck-Institute of Biochemistry, Am Klopferspitz 18, D-82152 Martinsried, Germany
| | - Ksenia Finogenova
- Department of Structural Cell Biology, Max-Planck-Institute of Biochemistry, Am Klopferspitz 18, D-82152 Martinsried, Germany
| | - Mireille Melko
- Department of Molecular Biology and Genetics, Aarhus University, C.F. Møllers Alle 3, 8000C Aarhus, Denmark
| | - Christian Benda
- Department of Structural Cell Biology, Max-Planck-Institute of Biochemistry, Am Klopferspitz 18, D-82152 Martinsried, Germany
| | - Søren Lykke-Andersen
- Department of Molecular Biology and Genetics, Aarhus University, C.F. Møllers Alle 3, 8000C Aarhus, Denmark
| | - Torben Heick Jensen
- Department of Molecular Biology and Genetics, Aarhus University, C.F. Møllers Alle 3, 8000C Aarhus, Denmark
| | - Elena Conti
- Department of Structural Cell Biology, Max-Planck-Institute of Biochemistry, Am Klopferspitz 18, D-82152 Martinsried, Germany
| |
Collapse
|
36
|
Zinder JC, Wasmuth EV, Lima CD. Nuclear RNA Exosome at 3.1 Å Reveals Substrate Specificities, RNA Paths, and Allosteric Inhibition of Rrp44/Dis3. Mol Cell 2016; 64:734-745. [PMID: 27818140 DOI: 10.1016/j.molcel.2016.09.038] [Citation(s) in RCA: 75] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2016] [Revised: 09/12/2016] [Accepted: 09/28/2016] [Indexed: 01/24/2023]
Abstract
The eukaryotic RNA exosome is an essential and conserved 3'-to-5' exoribonuclease complex that degrades or processes nearly every class of cellular RNA. The nuclear RNA exosome includes a 9-subunit non-catalytic core that binds Rrp44 (Dis3) and Rrp6 subunits to modulate their processive and distributive 3'-to-5' exoribonuclease activities, respectively. Here we utilize an engineered RNA with two 3' ends to obtain a crystal structure of an 11-subunit nuclear exosome bound to RNA at 3.1 Å. The structure reveals an extended RNA path to Rrp6 that penetrates into the non-catalytic core; contacts between the non-catalytic core and Rrp44, which inhibit exoribonuclease activity; and features of the Rrp44 exoribonuclease site that support its ability to degrade 3' phosphate RNA substrates. Using reconstituted exosome complexes, we show that 3' phosphate RNA is not a substrate for Rrp6 but is readily degraded by Rrp44 in the nuclear exosome.
Collapse
Affiliation(s)
- John C Zinder
- Tri-Institutional Training Program in Chemical Biology, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA; Structural Biology Program, Sloan Kettering Institute, 1275 York Avenue, New York, NY 10065, USA
| | - Elizabeth V Wasmuth
- Structural Biology Program, Sloan Kettering Institute, 1275 York Avenue, New York, NY 10065, USA
| | - Christopher D Lima
- Structural Biology Program, Sloan Kettering Institute, 1275 York Avenue, New York, NY 10065, USA; Howard Hughes Medical Institute, 1275 York Avenue, New York, NY 10065, USA.
| |
Collapse
|
37
|
Bonizzato A, Gaffo E, te Kronnie G, Bortoluzzi S. CircRNAs in hematopoiesis and hematological malignancies. Blood Cancer J 2016; 6:e483. [PMID: 27740630 PMCID: PMC5098259 DOI: 10.1038/bcj.2016.81] [Citation(s) in RCA: 120] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2016] [Accepted: 08/11/2016] [Indexed: 12/12/2022] Open
Abstract
Cell states in hematopoiesis are controlled by master regulators and by complex circuits of a growing family of RNA species impacting cell phenotype maintenance and plasticity. Circular RNAs (circRNAs) are rapidly gaining the status of particularly stable transcriptome members with distinctive qualities. RNA-seq identified thousands of circRNAs with developmental stage- and tissue-specific expression corroborating earlier suggestions that circular isoforms are a natural feature of the cell expression program. CircRNAs are abundantly expressed also in the hematopoietic compartment. There are a number of studies on circRNAs in blood cells, a specific overview is however lacking. In this review we first present current insight in circRNA biogenesis discussing the relevance for hematopoiesis of the highly interleaved processes of splicing and circRNA biogenesis. Regarding molecular functions circRNAs modulate host gene expression, but also compete for binding of microRNAs, RNA-binding proteins or translation initiation and participate in regulatory circuits. We examine circRNA expression in the hematopoietic compartment and in hematologic malignancies and review the recent breakthrough study that identified pathogenic circRNAs derived from leukemia fusion genes. CircRNA high and regulated expression in blood cell types indicate that further studies are warranted to inform the position of these regulators in normal and malignant hematopoiesis.
Collapse
Affiliation(s)
- A Bonizzato
- Department of Women's and Children's Health, University of Padova, Padova, Italy
| | - E Gaffo
- Department of Molecular Medicine, University of Padova, Padova, Italy
| | - G te Kronnie
- Department of Women's and Children's Health, University of Padova, Padova, Italy
| | - S Bortoluzzi
- Department of Molecular Medicine, University of Padova, Padova, Italy
| |
Collapse
|
38
|
Morales JC, Richard P, Patidar PL, Motea EA, Dang TT, Manley JL, Boothman DA. XRN2 Links Transcription Termination to DNA Damage and Replication Stress. PLoS Genet 2016; 12:e1006107. [PMID: 27437695 PMCID: PMC4954731 DOI: 10.1371/journal.pgen.1006107] [Citation(s) in RCA: 74] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Accepted: 05/14/2016] [Indexed: 11/18/2022] Open
Abstract
XRN2 is a 5’-3’ exoribonuclease implicated in transcription termination. Here we demonstrate an unexpected role for XRN2 in the DNA damage response involving resolution of R-loop structures and prevention of DNA double-strand breaks (DSBs). We show that XRN2 undergoes DNA damage-inducible nuclear re-localization, co-localizing with 53BP1 and R loops, in a transcription and R-loop-dependent process. XRN2 loss leads to increased R loops, genomic instability, replication stress, DSBs and hypersensitivity of cells to various DNA damaging agents. We demonstrate that the DSBs that arise with XRN2 loss occur at transcriptional pause sites. XRN2-deficient cells also exhibited an R-loop- and transcription-dependent delay in DSB repair after ionizing radiation, suggesting a novel role for XRN2 in R-loop resolution, suppression of replication stress, and maintenance of genomic stability. Our study highlights the importance of regulating transcription-related activities as a critical component in maintaining genetic stability. Genomic instability is one of the primary causes of disease states, in particular cancer. One major cause of genomic instability is the formation of DNA double strand breaks (DSBs), which are one of the most dangerous types of DNA lesions the cell can encounter. If not repaired in a timely manner, one DSB can lead not only to cell death. If misrepaired, one DSB can lead to a hazardous chromosomal aberration, such as a translocation, that can eventually lead to cancer. The cell encounters and repairs DSBs that arise from naturally occurring cellular processes on a daily basis. A number of studies have demonstrated that aberrant structures that form during transcription under certain circumstances, in particular RNA:DNA hybrids (R loops), can lead to DSB formation and genomic instability, especially during DNA synthesis. Thus, it is important to understand how the cell responds and repairs transcription-mediated DNA damage in general and R loop-related DNA damage in particular. This paper both demonstrates that the XRN transcription termination factor links transcription and DNA damage, but also provides a better understanding of how the cell prevents transcription-related DNA damage.
Collapse
Affiliation(s)
- Julio C. Morales
- Department of Neurosurgery, University of Oklahoma Health Science Center, Oklahoma City, Oklahoma, United States of America
- * E-mail: (JCM); (DAB)
| | - Patricia Richard
- Department of Biological Sciences, Columbia University, New York, New York, United States of America
| | - Praveen L. Patidar
- Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Edward A. Motea
- Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Tuyen T. Dang
- Department of Neurosurgery, University of Oklahoma Health Science Center, Oklahoma City, Oklahoma, United States of America
| | - James L. Manley
- Department of Biological Sciences, Columbia University, New York, New York, United States of America
| | - David A. Boothman
- Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
- * E-mail: (JCM); (DAB)
| |
Collapse
|
39
|
Li J, Yang X, Guan H, Mizokami A, Keller ET, Xu X, Liu X, Tan J, Hu L, Lu Y, Zhang J. Exosome-derived microRNAs contribute to prostate cancer chemoresistance. Int J Oncol 2016; 49:838-46. [PMID: 27278879 DOI: 10.3892/ijo.2016.3560] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2016] [Accepted: 05/20/2016] [Indexed: 02/06/2023] Open
Abstract
Certain microRNAs (miRNAs) play a key role in cancer cell chemoresistance. However, the pleiotropic functions of exosome-derived miRNAs on developing chemoresistance remain unknown. In the present study, we aimed to construct potential networks of miRNAs, which derived from the exosome of chemoresistant prostate cancer (PCa) cells, with their known target genes using miRNA expression profiling and bioinformatic tools. Global miRNA expression profiles were measured by microarray. Twelve miRNAs were initially selected and validated by qRT-PCR. Known targets of deregulated miRNAs were utilized using DIANA-TarBase database v6.0. The incorporation of deregulated miRNAs and target genes into KEGG pathways were utilized using DIANA-mirPath software. To construct potential miRNA regulatory networks, the overlapping parts of miRNAs and their targer genes from the selected KEGG pathway 'PCa progression (hsa05215)' were visualized by Cytoscape software. We identified 29 deregulated miRNAs, including 19 upregulated and 10 downregulated, in exosome samples derived from two kinds of paclitaxel resistance PCa cells (PC3-TXR and DU145-TXR) compared with their parental cells (PC3 and DU145). The enrichment results of deregulated miRNAs and known target genes showed that a few pathways were correlated with several critical cell signaling pathways. We found that hub hsa-miR3176, -141-3p, -5004-5p, -16-5p, -3915, -488‑3p, -23c, -3673 and -3654 were potential targets to hub gene androgen receptor (AR) and phosphatase and tensin homolog (PTEN). Hub gene T-cell factors/lymphoid enhancer-binding factors 4 (TCF4) target genes were mainly regulated by hub hsa-miR-32-5, -141-3p, -606, -381 and -429. These results may provide a linkage between PCa chemoresistance and exosome regulatory networks and thus lead us to propose that AR, PTEN and TCF4 genes may be the important genes which are regulated by exosome miRNAs in chemoresistance cancer cells.
Collapse
Affiliation(s)
- Jing Li
- Key Laboratory of Longevity and Aging-Related Diseases, Ministry of Education, Nanning, Guangxi, P.R. China
| | - Xin Yang
- Key Laboratory of Longevity and Aging-Related Diseases, Ministry of Education, Nanning, Guangxi, P.R. China
| | - Hao Guan
- Key Laboratory of Longevity and Aging-Related Diseases, Ministry of Education, Nanning, Guangxi, P.R. China
| | | | - Evan T Keller
- Department of Urology and Pathology, School of Medicine, University of Michigan, Ann Arbor, MI, USA
| | - Xiaozhen Xu
- Key Laboratory of Longevity and Aging-Related Diseases, Ministry of Education, Nanning, Guangxi, P.R. China
| | - Xia Liu
- Key Laboratory of Longevity and Aging-Related Diseases, Ministry of Education, Nanning, Guangxi, P.R. China
| | - Jiyong Tan
- Key Laboratory of Longevity and Aging-Related Diseases, Ministry of Education, Nanning, Guangxi, P.R. China
| | - Longyuan Hu
- Key Laboratory of Longevity and Aging-Related Diseases, Ministry of Education, Nanning, Guangxi, P.R. China
| | - Yi Lu
- Key Laboratory of Longevity and Aging-Related Diseases, Ministry of Education, Nanning, Guangxi, P.R. China
| | - Jian Zhang
- Key Laboratory of Longevity and Aging-Related Diseases, Ministry of Education, Nanning, Guangxi, P.R. China
| |
Collapse
|
40
|
Mature maternal mRNAs are longer than zygotic ones and have complex degradation kinetics in sea urchin. Dev Biol 2016; 414:121-31. [PMID: 27085752 DOI: 10.1016/j.ydbio.2016.04.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2015] [Revised: 03/16/2016] [Accepted: 04/10/2016] [Indexed: 11/22/2022]
Abstract
Early in embryogenesis, maternally deposited transcripts are degraded and new zygotic transcripts are generated during the maternal to zygotic transition. Recent works have shown that early zygotic transcripts are short compared to maternal transcripts, in zebrafish and Drosophila species. The reduced zygotic transcript length was attributed to the short cell cycle in these organisms that prevents the transcription of long primary transcripts (intron delay). Here we study the length of maternal mRNAs and their degradation kinetics in two sea urchin species to further the understanding of maternal gene usage and processing. Early zygotic primary transcripts and mRNAs are shorter than maternal ones in the sea urchin, Strongylocentrotus purpuratus. Yet, while primary transcripts length increases when cell cycle lengthens, typical for intron delay, the relatively short length of zygotic mRNAs is consistent. The enhanced mRNA length is due to significantly longer maternal open reading frames and 3'UTRs compared to the zygotic lengths, a ratio that does not change with developmental time. This implies unique usage of both coding sequences and regulatory information in the maternal stage compared to the zygotic stages. We extracted the half-lifetimes due to maternal and zygotic degradation mechanisms from high-density time course of a set of maternal mRNAs in Paracentrotus lividus. The degradation rates due to maternal and zygotic degradation mechanisms are not correlated, indicating that these mechanisms are independent and relay on different regulatory information. Our studies illuminate specific structural and kinetic properties of sea urchin maternal mRNAs that might be broadly shared by other organisms.
Collapse
|
41
|
Abstract
Nuclear pore complexes (NPCs) are indispensable for cell function and are at the center of several human diseases. NPCs provide access to the nucleus and regulate the transport of proteins and RNA across the nuclear envelope. They are aqueous channels generated from a complex network of evolutionarily conserved proteins known as nucleporins. In this Cell Science at a Glance article and the accompanying poster, we discuss how transport between the nucleoplasm and the cytoplasm is regulated, what we currently know about the structure of individual nucleoporins and the assembled NPC, and how the cell regulates assembly and disassembly of such a massive structure. Our aim is to provide a general overview on what we currently know about the nuclear pore and point out directions of research this area is heading to.
Collapse
|
42
|
Vuković L, Chipot C, Makino DL, Conti E, Schulten K. Molecular Mechanism of Processive 3' to 5' RNA Translocation in the Active Subunit of the RNA Exosome Complex. J Am Chem Soc 2016; 138:4069-78. [PMID: 26928279 PMCID: PMC4988868 DOI: 10.1021/jacs.5b12065] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Recent experimental studies revealed structural details of 3' to 5' degradation of RNA molecules, performed by the exosome complex. ssRNA is channeled through its multisubunit ring-like core into the active site tunnel of its key exonuclease subunit Rrp44, which acts both as an enzyme and a motor. Even in isolation, Rrp44 can pull and sequentially cleave RNA nucleotides, one at a time, without any external energy input and release a final 3-5 nucleotide long product. Using molecular dynamics simulations, we identify the main factors that control these processes. Our free energy calculations reveal that RNA transfer from solution into the active site of Rrp44 is highly favorable, but dependent on the length of the RNA strand. While RNA strands formed by 5 nucleotides or more correspond to a decreasing free energy along the translocation coordinate toward the cleavage site, a 4-nucleotide RNA experiences a free energy barrier along the same direction, potentially leading to incomplete cleavage of ssRNA and the release of short (3-5) nucleotide products. We provide new insight into how Rrp44 catalyzes a localized enzymatic reaction and performs an action distributed over several RNA nucleotides, leading eventually to the translocation of whole RNA segments into the position suitable for cleavage.
Collapse
Affiliation(s)
- Lela Vuković
- Department of Physics, University of Illinois at Urbana-Champaign, Urbana, IL 61801, United States
- Center for the Physics of Living Cells, University of Illinois at Urbana-Champaign, Urbana, IL 61801, United States
- Beckman Institute, University of Illinois at Urbana-Champaign, Urbana, IL 61801, United States
- epartment of Chemistry, University of Texas at El Paso, El Paso, TX 79968, United States
| | - Christophe Chipot
- Department of Physics, University of Illinois at Urbana-Champaign, Urbana, IL 61801, United States
- Beckman Institute, University of Illinois at Urbana-Champaign, Urbana, IL 61801, United States
- Laboratoire International Associé CNRS-University of Illinois, Université de Lorraine, Vandoeuvre-lès-Nancy, France
| | - Debora L. Makino
- Department of Structural Cell Biology, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Elena Conti
- Department of Structural Cell Biology, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Klaus Schulten
- Department of Physics, University of Illinois at Urbana-Champaign, Urbana, IL 61801, United States
- Center for the Physics of Living Cells, University of Illinois at Urbana-Champaign, Urbana, IL 61801, United States
- Beckman Institute, University of Illinois at Urbana-Champaign, Urbana, IL 61801, United States
| |
Collapse
|
43
|
Yan X, Guo W, Yuan YA. Crystal structures of CRISPR-associated Csx3 reveal a manganese-dependent deadenylation exoribonuclease. RNA Biol 2016; 12:749-60. [PMID: 26106927 DOI: 10.1080/15476286.2015.1051300] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
In prokaryotes, the CRISPR/Cas system is known to target and degrade invading phages and foreign genetic elements upon subsequent infection. However, the structure and function of many Cas proteins remain largely unknown, due to the high diversity of Cas proteins. Here we report 3 crystal structures of Archaeoglobus fulgidus Csx3 (AfCsx3) in free form, in complex with manganese ions and in complex with a single-stranded RNA (ssRNA) fragment, respectively. AfCsx3 harbors a ferredoxin-like fold and forms dimer both in the crystal and in solution. Our structure-based biochemical analysis demonstrates that the RNA binding sites and cleavage sites are located at 2 separate surfaces within the AfCsx3 dimer, suggesting a model to bind, tether and cleave the incoming RNA substrate. In addition, AfCsx3 displays robust 3'-deadenylase activity in the presence of manganese ions, which strongly suggests that AfCsx3 functions as a deadenylation exonuclease. Taken together, our results indicate that AfCsx3 is a Cas protein involved in RNA deadenylation and provide a framework for understanding the role of AfCsx3 in the Type III-B CRISPR/Cas system.
Collapse
Affiliation(s)
- Xinfu Yan
- a Department of Biological Sciences and Center for Bioimaging Sciences; National University of Singapore ; Singapore , Singapore
| | | | | |
Collapse
|
44
|
DeVilbiss AW, Tanimura N, McIver SC, Katsumura KR, Johnson KD, Bresnick EH. Navigating Transcriptional Coregulator Ensembles to Establish Genetic Networks: A GATA Factor Perspective. Curr Top Dev Biol 2016; 118:205-44. [PMID: 27137658 DOI: 10.1016/bs.ctdb.2016.01.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Complex developmental programs require orchestration of intrinsic and extrinsic signals to control cell proliferation, differentiation, and survival. Master regulatory transcription factors are vital components of the machinery that transduce these stimuli into cellular responses. This is exemplified by the GATA family of transcription factors that establish cell type-specific genetic networks and control the development and homeostasis of systems including blood, vascular, adipose, and cardiac. Dysregulated GATA factor activity/expression underlies anemia, immunodeficiency, myelodysplastic syndrome, and leukemia. Parameters governing the capacity of a GATA factor expressed in multiple cell types to generate cell type-specific transcriptomes include selective coregulator usage and target gene-specific chromatin states. As knowledge of GATA-1 mechanisms in erythroid cells constitutes a solid foundation, we will focus predominantly on GATA-1, while highlighting principles that can be extrapolated to other master regulators. GATA-1 interacts with ubiquitous and lineage-restricted transcription factors, chromatin modifying/remodeling enzymes, and other coregulators to activate or repress transcription and to maintain preexisting transcriptional states. Major unresolved issues include: how does a GATA factor selectively utilize diverse coregulators; do distinct epigenetic landscapes and nuclear microenvironments of target genes dictate coregulator requirements; and do gene cohorts controlled by a common coregulator ensemble function in common pathways. This review will consider these issues in the context of GATA factor-regulated hematopoiesis and from a broader perspective.
Collapse
Affiliation(s)
- A W DeVilbiss
- UW-Carbone Cancer Center, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States; UW-Madison Blood Research Program, Madison, WI, United States
| | - N Tanimura
- UW-Carbone Cancer Center, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States; UW-Madison Blood Research Program, Madison, WI, United States
| | - S C McIver
- UW-Carbone Cancer Center, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States; UW-Madison Blood Research Program, Madison, WI, United States
| | - K R Katsumura
- UW-Carbone Cancer Center, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States; UW-Madison Blood Research Program, Madison, WI, United States
| | - K D Johnson
- UW-Carbone Cancer Center, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States; UW-Madison Blood Research Program, Madison, WI, United States
| | - E H Bresnick
- UW-Carbone Cancer Center, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States; UW-Madison Blood Research Program, Madison, WI, United States.
| |
Collapse
|
45
|
Audin MJC, Wurm JP, Cvetkovic MA, Sprangers R. The oligomeric architecture of the archaeal exosome is important for processive and efficient RNA degradation. Nucleic Acids Res 2016; 44:2962-73. [PMID: 26837575 PMCID: PMC4824110 DOI: 10.1093/nar/gkw062] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Accepted: 01/25/2016] [Indexed: 11/30/2022] Open
Abstract
The exosome plays an important role in RNA degradation and processing. In archaea, three Rrp41:Rrp42 heterodimers assemble into a barrel like structure that contains a narrow RNA entrance pore and a lumen that contains three active sites. Here, we demonstrate that this quaternary structure of the exosome is important for efficient RNA degradation. We find that the entrance pore of the barrel is required for nM substrate affinity. This strong interaction is crucial for processive substrate degradation and prevents premature release of the RNA from the enzyme. Using methyl TROSY NMR techniques, we establish that the 3′ end of the substrate remains highly flexible inside the lumen. As a result, the RNA jumps between the three active sites that all equally participate in substrate degradation. The RNA jumping rate is, however, much faster than the cleavage rate, indicating that not all active site:substrate encounters result in catalysis. Enzymatic turnover therefore benefits from the confinement of the active sites and substrate in the lumen, which ensures that the RNA is at all times bound to one of the active sites. The evolution of the exosome into a hexameric complex and the optimization of its catalytic efficiency were thus likely co-occurring events.
Collapse
Affiliation(s)
- Maxime J C Audin
- Max Planck Institute for Developmental Biology, Spemannstrasse 35, 72076 Tübingen, Germany
| | - Jan Philip Wurm
- Max Planck Institute for Developmental Biology, Spemannstrasse 35, 72076 Tübingen, Germany
| | - Milos A Cvetkovic
- Max Planck Institute for Developmental Biology, Spemannstrasse 35, 72076 Tübingen, Germany
| | - Remco Sprangers
- Max Planck Institute for Developmental Biology, Spemannstrasse 35, 72076 Tübingen, Germany
| |
Collapse
|
46
|
Matia-González AM, Laing EE, Gerber AP. Conserved mRNA-binding proteomes in eukaryotic organisms. Nat Struct Mol Biol 2015; 22:1027-33. [PMID: 26595419 PMCID: PMC5759928 DOI: 10.1038/nsmb.3128] [Citation(s) in RCA: 128] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2015] [Accepted: 10/23/2015] [Indexed: 12/12/2022]
Abstract
RNA-binding proteins (RBPs) are essential for the post-transcriptional regulation of gene expression. Recent high-throughput screens have dramatically increased the number of experimentally identified RBPs; however, comprehensive identification of RBPs within living organisms is elusive. Here we describe the repertoire of 765 and 594 proteins that reproducibly interact with polyadenylated mRNAs in Saccharomyces cerevisiae and Caenorhabditis elegans, respectively. Furthermore, we report the differential association of mRBPs upon apoptosis induction in C. elegans L4 stage larvae. Strikingly, most proteins comprising mRNA-binding proteomes (mRBPomes) are evolutionarily conserved between yeast and C. elegans, including components of early metabolic pathways and the proteasome. Based on our evidence that glycolytic enzymes bind to distinct glycolytic mRNAs, we speculate that enzyme-mRNA interactions relate to an ancient mechanism for post-transcriptional coordination of metabolic pathways, perhaps established during the transition from the early RNA to the protein ‘world’.
Collapse
Affiliation(s)
- Ana M Matia-González
- Department of Microbial and Cellular Sciences, School of Biosciences and Medicine, Faculty of Health and Medical Sciences, University of Surrey, Guildford, UK
| | - Emma E Laing
- Department of Microbial and Cellular Sciences, School of Biosciences and Medicine, Faculty of Health and Medical Sciences, University of Surrey, Guildford, UK
| | - André P Gerber
- Department of Microbial and Cellular Sciences, School of Biosciences and Medicine, Faculty of Health and Medical Sciences, University of Surrey, Guildford, UK
| |
Collapse
|
47
|
|
48
|
Müller JS, Giunta M, Horvath R. Exosomal Protein Deficiencies: How Abnormal RNA Metabolism Results in Childhood-Onset Neurological Diseases. J Neuromuscul Dis 2015; 2:S31-S37. [PMID: 27127732 PMCID: PMC4845884 DOI: 10.3233/jnd-150086] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Defects of RNA metabolism have been increasingly identified in various forms of inherited neurological diseases. Recently, abnormal RNA degradation due to mutations in human exosome subunit genes has been shown to cause complex childhood onset neurological presentations including spinal muscular atrophy, pontocerebellar hypoplasia and myelination deficiencies. This paper summarizes our current knowledge about the exosome in human neurological disease and provides some important insights into potential disease mechanisms.
Collapse
Affiliation(s)
- Juliane S. Müller
- Institute of Genetic Medicine, The John Walton Muscular Dystrophy Research Centre, Wellcome Trust Centre for Mitochondrial Research, Newcastle University, Newcastle upon Tyne, UK
| | - Michele Giunta
- Institute of Genetic Medicine, The John Walton Muscular Dystrophy Research Centre, Wellcome Trust Centre for Mitochondrial Research, Newcastle University, Newcastle upon Tyne, UK
| | - Rita Horvath
- Institute of Genetic Medicine, The John Walton Muscular Dystrophy Research Centre, Wellcome Trust Centre for Mitochondrial Research, Newcastle University, Newcastle upon Tyne, UK
| |
Collapse
|
49
|
Ye SB, Li ZL, Luo DH, Huang BJ, Chen YS, Zhang XS, Cui J, Zeng YX, Li J. Tumor-derived exosomes promote tumor progression and T-cell dysfunction through the regulation of enriched exosomal microRNAs in human nasopharyngeal carcinoma. Oncotarget 2015; 5:5439-52. [PMID: 24978137 PMCID: PMC4170615 DOI: 10.18632/oncotarget.2118] [Citation(s) in RCA: 261] [Impact Index Per Article: 29.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Tumor-derived exosomes contain biologically active proteins and messenger and microRNAs (miRNAs). These particles serve as vehicles of intercellular communication and are emerging mediators of tumorigenesis and immune escape. Here, we isolated 30-100 nm exosomes from the serum of patients with nasopharyngeal carcinoma (NPC) or the supernatant of TW03 cells. Increased circulating exosome concentrations were correlated with advanced lymphoid node stage and poor prognosis in NPC patients (P < 0.05). TW03-derived exosomes impaired T-cell function by inhibiting T-cell proliferation and Th1 and Th17 differentiation and promoting Treg induction by NPC cells in vitro. These results are associated with decreases in ERK, STAT1, and STAT3 phosphorylation and increases in STAT5 phosphorylation in exosome-stimulated T-cells. TW03-derived exosomes increased the proinflammatory cytokines IL-1β, IL-6, and IL-10 but decreased IFNγ, IL-2, and IL-17 release from CD4+ or CD8+ T-cells. Furthermore, five commonly over-expressed miRNAs were identified in the exosomes from patient sera or NPC cells: hsa-miR-24-3p, hsa-miR-891a, hsa-miR-106a-5p, hsa-miR-20a-5p, and hsa-miR-1908. These over-expressed miRNA clusters down-regulated the MARK1 signaling pathway to alter cell proliferation and differentiation. Overall, these observations reveal the clinical relevance and prognostic value of tumor-derived exosomes and identify a unique intercellular mechanism mediated by tumor-derived exosomes to modulate T-cell function in NPC.
Collapse
Affiliation(s)
- Shu-Biao Ye
- State Key Laboratory of Oncology in South China, Sun Yat-Sen University Cancer Center, Guangzhou, China. Collaborative Innovation Center of Cancer Medicine, Sun Yat-Sen University Cancer Center, Guangzhou, China. Department of Biotherapy, Sun Yat-Sen University Cancer Center, Guangzhou, China
| | - Ze-Lei Li
- State Key Laboratory of Oncology in South China, Sun Yat-Sen University Cancer Center, Guangzhou, China. Collaborative Innovation Center of Cancer Medicine, Sun Yat-Sen University Cancer Center, Guangzhou, China. Department of Biotherapy, Sun Yat-Sen University Cancer Center, Guangzhou, China
| | - Dong-Hua Luo
- State Key Laboratory of Oncology in South China, Sun Yat-Sen University Cancer Center, Guangzhou, China. Collaborative Innovation Center of Cancer Medicine, Sun Yat-Sen University Cancer Center, Guangzhou, China. Department of Nasopharyngeal Carcinoma, Sun Yat-Sen University Cancer Center, Guangzhou, China
| | - Bi-Jun Huang
- State Key Laboratory of Oncology in South China, Sun Yat-Sen University Cancer Center, Guangzhou, China. Collaborative Innovation Center of Cancer Medicine, Sun Yat-Sen University Cancer Center, Guangzhou, China
| | - Yu-Suan Chen
- State Key Laboratory of Oncology in South China, Sun Yat-Sen University Cancer Center, Guangzhou, China. Collaborative Innovation Center of Cancer Medicine, Sun Yat-Sen University Cancer Center, Guangzhou, China. Department of Radiotherapy, Sun Yat-Sen University Cancer Center, Guangzhou, China
| | - Xiao-Shi Zhang
- State Key Laboratory of Oncology in South China, Sun Yat-Sen University Cancer Center, Guangzhou, China. Collaborative Innovation Center of Cancer Medicine, Sun Yat-Sen University Cancer Center, Guangzhou, China. Department of Biotherapy, Sun Yat-Sen University Cancer Center, Guangzhou, China
| | - Jun Cui
- Key Laboratory of Gene Engineering of the Ministry of Education, State Key Laboratory of Biocontrol, College of Life Sciences, Sun Yat-sen University, Guangzhou, China
| | - Yi-Xin Zeng
- State Key Laboratory of Oncology in South China, Sun Yat-Sen University Cancer Center, Guangzhou, China. Collaborative Innovation Center of Cancer Medicine, Sun Yat-Sen University Cancer Center, Guangzhou, China
| | - Jiang Li
- State Key Laboratory of Oncology in South China, Sun Yat-Sen University Cancer Center, Guangzhou, China. Collaborative Innovation Center of Cancer Medicine, Sun Yat-Sen University Cancer Center, Guangzhou, China. Department of Biotherapy, Sun Yat-Sen University Cancer Center, Guangzhou, China
| |
Collapse
|
50
|
Kowalinski E, Schuller A, Green R, Conti E. Saccharomyces cerevisiae Ski7 Is a GTP-Binding Protein Adopting the Characteristic Conformation of Active Translational GTPases. Structure 2015; 23:1336-43. [PMID: 26051716 PMCID: PMC4509514 DOI: 10.1016/j.str.2015.04.018] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2015] [Revised: 04/29/2015] [Accepted: 04/29/2015] [Indexed: 01/04/2023]
Abstract
Ski7 is a cofactor of the cytoplasmic exosome in budding yeast, functioning in both mRNA turnover and non-stop decay (NSD), a surveillance pathway that degrades faulty mRNAs lacking a stop codon. The C-terminal region of Ski7 (Ski7C) shares overall sequence similarity with the translational GTPase (trGTPase) Hbs1, but whether Ski7 has retained the properties of a trGTPase is unclear. Here, we report the high-resolution structures of Ski7C bound to either intact guanosine triphosphate (GTP) or guanosine diphosphate-Pi. The individual domains of Ski7C adopt the conformation characteristic of active trGTPases. Furthermore, the nucleotide-binding site of Ski7C shares similar features compared with active trGTPases, notably the presence of a characteristic monovalent cation. However, a suboptimal polar residue at the putative catalytic site and an unusual polar residue that interacts with the γ-phosphate of GTP distinguish Ski7 from other trGTPases, suggesting it might function rather as a GTP-binding protein than as a GTP-hydrolyzing enzyme.
Collapse
Affiliation(s)
- Eva Kowalinski
- Department of Structural Cell Biology Department, Max Planck Institute of Biochemistry, Am Klopferspitz 18, 82152 Martinsried, Germany
| | - Anthony Schuller
- Howard Hughes Medical Institute, Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Rachel Green
- Howard Hughes Medical Institute, Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Elena Conti
- Department of Structural Cell Biology Department, Max Planck Institute of Biochemistry, Am Klopferspitz 18, 82152 Martinsried, Germany.
| |
Collapse
|