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Dai Z, Yang X. The regulation of liquid-liquid phase separated condensates containing nucleic acids. FEBS J 2024; 291:2320-2331. [PMID: 37735903 DOI: 10.1111/febs.16959] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Revised: 08/31/2023] [Accepted: 09/12/2023] [Indexed: 09/23/2023]
Abstract
Liquid-liquid phase separation (LLPS) has been recognized as a universal biological phenomenon. It plays an important role in life activities. LLPS is induced by weak interactions between intrinsically disordered regions or low complex domains. Nucleic acids are widely present in cells, and shown to be closely related to LLPS. Their structure and electronegativity provide the excellent platforms for the formation of phase-separated condensates. In this review, we summarize the interconnected regulation between nucleic acids and LLPS demonstrated in in vivo and in vitro studies. Beside homogeneous and single-phase condensates, complicated and multicompartment LLPS induced by nucleic acids is discussed as well. Recent advances about nucleic-acid-induced LLPS as a new pathogenic mechanism and drug design direction are highlighted, especially virus-mediated disease treatment and prevention.
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Affiliation(s)
- Zhuojun Dai
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou, China
| | - Xiaorong Yang
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou, China
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2
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Mathias KM, Liu Y, Wan L. Dysregulation of transcriptional condensates in human disease: mechanisms, biological functions, and open questions. Curr Opin Genet Dev 2024; 86:102203. [PMID: 38788489 PMCID: PMC11162900 DOI: 10.1016/j.gde.2024.102203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Revised: 04/18/2024] [Accepted: 04/22/2024] [Indexed: 05/26/2024]
Abstract
Precise gene expression, crucial for normal development and health, depends on the co-ordinated assembly and function of various factors within the crowded nucleus. Recent evidence suggests that this process is in part regulated by mesoscale compartmentalization and concentration of transcriptional components within condensates, offering a new perspective on gene regulation. Dysregulation of transcriptional condensates is increasingly associated with diseases, indicating a potential role in pathogenesis. In this mini-review, we provide a concise overview of the current understanding of the formation and function of transcriptional condensates, with a specific focus on recent advances in their dysregulation and implications in diseases, notably cancer. We also address limitations in the field and highlight open questions for future research.
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Affiliation(s)
- Kaeli M Mathias
- Department of Cancer Biology and Abramson Family Cancer Research Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; Biochemistry Biophysics Chemical Biology Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; Center for Computational and Genomic Medicine, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Yiman Liu
- Department of Cancer Biology and Abramson Family Cancer Research Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Liling Wan
- Department of Cancer Biology and Abramson Family Cancer Research Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; Center for Computational and Genomic Medicine, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA; Epigenetics Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; Institute for Regenerative Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
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3
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Pantier R, Brown M, Han S, Paton K, Meek S, Montavon T, Shukeir N, McHugh T, Kelly DA, Hochepied T, Libert C, Jenuwein T, Burdon T, Bird A. MeCP2 binds to methylated DNA independently of phase separation and heterochromatin organisation. Nat Commun 2024; 15:3880. [PMID: 38719804 PMCID: PMC11079052 DOI: 10.1038/s41467-024-47395-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Accepted: 03/29/2024] [Indexed: 05/12/2024] Open
Abstract
Correlative evidence has suggested that the methyl-CpG-binding protein MeCP2 contributes to the formation of heterochromatin condensates via liquid-liquid phase separation. This interpretation has been reinforced by the observation that heterochromatin, DNA methylation and MeCP2 co-localise within prominent foci in mouse cells. The findings presented here revise this view. MeCP2 localisation is independent of heterochromatin as MeCP2 foci persist even when heterochromatin organisation is disrupted. Additionally, MeCP2 foci fail to show hallmarks of phase separation in live cells. Importantly, we find that mouse cellular models are highly atypical as MeCP2 distribution is diffuse in most mammalian species, including humans. Notably, MeCP2 foci are absent in Mus spretus which is a mouse subspecies lacking methylated satellite DNA repeats. We conclude that MeCP2 has no intrinsic tendency to form condensates and its localisation is independent of heterochromatin. Instead, the distribution of MeCP2 in the nucleus is primarily determined by global DNA methylation patterns.
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Affiliation(s)
- Raphaël Pantier
- The Wellcome Centre for Cell Biology, University of Edinburgh, Michael Swann Building, Max Born Crescent, The King's Buildings, Edinburgh, EH9 3BF, UK
| | - Megan Brown
- The Wellcome Centre for Cell Biology, University of Edinburgh, Michael Swann Building, Max Born Crescent, The King's Buildings, Edinburgh, EH9 3BF, UK
| | - Sicheng Han
- The Wellcome Centre for Cell Biology, University of Edinburgh, Michael Swann Building, Max Born Crescent, The King's Buildings, Edinburgh, EH9 3BF, UK
| | - Katie Paton
- The Wellcome Centre for Cell Biology, University of Edinburgh, Michael Swann Building, Max Born Crescent, The King's Buildings, Edinburgh, EH9 3BF, UK
| | - Stephen Meek
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush, Midlothian, EH25 9RG, UK
| | - Thomas Montavon
- Max Planck Institute of Immunobiology and Epigenetics, Stübeweg 51, 79108, Freiburg, Germany
| | - Nicholas Shukeir
- Max Planck Institute of Immunobiology and Epigenetics, Stübeweg 51, 79108, Freiburg, Germany
| | - Toni McHugh
- The Wellcome Centre for Cell Biology, University of Edinburgh, Michael Swann Building, Max Born Crescent, The King's Buildings, Edinburgh, EH9 3BF, UK
| | - David A Kelly
- The Wellcome Centre for Cell Biology, University of Edinburgh, Michael Swann Building, Max Born Crescent, The King's Buildings, Edinburgh, EH9 3BF, UK
| | - Tino Hochepied
- Center for Inflammation Research, VIB, Ghent, Belgium
- Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
| | - Claude Libert
- Center for Inflammation Research, VIB, Ghent, Belgium
- Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
| | - Thomas Jenuwein
- Max Planck Institute of Immunobiology and Epigenetics, Stübeweg 51, 79108, Freiburg, Germany
| | - Tom Burdon
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush, Midlothian, EH25 9RG, UK
| | - Adrian Bird
- The Wellcome Centre for Cell Biology, University of Edinburgh, Michael Swann Building, Max Born Crescent, The King's Buildings, Edinburgh, EH9 3BF, UK.
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4
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Niekamp S, Marr SK, Oei TA, Subramanian R, Kingston RE. Modularity of PRC1 composition and chromatin interaction define condensate properties. Mol Cell 2024; 84:1651-1666.e12. [PMID: 38521066 DOI: 10.1016/j.molcel.2024.03.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2023] [Revised: 01/04/2024] [Accepted: 02/29/2024] [Indexed: 03/25/2024]
Abstract
Polycomb repressive complexes (PRCs) play a key role in gene repression and are indispensable for proper development. Canonical PRC1 forms condensates in vitro and in cells that are proposed to contribute to the maintenance of repression. However, how chromatin and the various subunits of PRC1 contribute to condensation is largely unexplored. Using a reconstitution approach and single-molecule imaging, we demonstrate that nucleosomal arrays and PRC1 act synergistically, reducing the critical concentration required for condensation by more than 20-fold. We find that the exact combination of PHC and CBX subunits determines condensate initiation, morphology, stability, and dynamics. Particularly, PHC2's polymerization activity influences condensate dynamics by promoting the formation of distinct domains that adhere to each other but do not coalesce. Live-cell imaging confirms CBX's role in condensate initiation and highlights PHC's importance for condensate stability. We propose that PRC1 composition can modulate condensate properties, providing crucial regulatory flexibility across developmental stages.
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Affiliation(s)
- Stefan Niekamp
- Department of Molecular Biology, Massachusetts General Hospital Research Institute, Massachusetts General Hospital, Boston, MA 02114, USA; Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
| | - Sharon K Marr
- Department of Molecular Biology, Massachusetts General Hospital Research Institute, Massachusetts General Hospital, Boston, MA 02114, USA; Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
| | - Theresa A Oei
- Department of Molecular Biology, Massachusetts General Hospital Research Institute, Massachusetts General Hospital, Boston, MA 02114, USA; Department of Genetics, Harvard Medical School, Boston, MA 02115, USA; Department of Chemical Biology, Harvard University, Cambridge, MA 02138, USA
| | - Radhika Subramanian
- Department of Molecular Biology, Massachusetts General Hospital Research Institute, Massachusetts General Hospital, Boston, MA 02114, USA; Department of Genetics, Harvard Medical School, Boston, MA 02115, USA.
| | - Robert E Kingston
- Department of Molecular Biology, Massachusetts General Hospital Research Institute, Massachusetts General Hospital, Boston, MA 02114, USA; Department of Genetics, Harvard Medical School, Boston, MA 02115, USA.
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5
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Maurici N, Phan TM, Henty-Ridilla JL, Kim YC, Mittal J, Bah A. Uncovering the molecular interactions underlying MBD2 and MBD3 phase separation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.29.591564. [PMID: 38746378 PMCID: PMC11092444 DOI: 10.1101/2024.04.29.591564] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2024]
Abstract
Chromatin organization controls DNA's accessibility to regulatory factors to influence gene expression. Heterochromatin, or transcriptionally silent chromatin enriched in methylated DNA and methylated histone tails, self-assembles through multivalent interactions with its associated proteins into a condensed, but dynamic state. Liquid-liquid phase separation (LLPS) of key heterochromatin regulators, such as heterochromatin protein 1 (HP1), plays an essential role in heterochromatin assembly and function. Methyl-CpG-binding protein 2 (MeCP2), the most studied member of the methyl-CpG-binding domain (MBD) family of proteins, has been recently shown to undergo LLPS in the absence and presence of methylated DNA. These studies provide a new mechanistic framework for understanding the role of methylated DNA and its readers in heterochromatin formation. However, the details of the molecular interactions by which other MBD family members undergo LLPS to mediate genome organization and transcriptional regulation are not fully understood. Here, we focus on two MBD proteins, MBD2 and MBD3, that have distinct but interdependent roles in gene regulation. Using an integrated computational and experimental approach, we uncover the homotypic and heterotypic interactions governing MBD2 and MBD3 phase separation and DNA's influence on this process. We show that despite sharing the highest sequence identity and structural homology among all the MBD protein family members, MBD2 and MBD3 exhibit differing residue patterns resulting in distinct phase separation mechanisms. Understanding the molecular underpinnings of MBD protein condensation offers insights into the higher-order, LLPS-mediated organization of heterochromatin.
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Ren P, Tong X, Li J, Jiang H, Liu S, Li X, Lai M, Yang W, Rong Y, Zhang Y, Jin J, Ma Y, Pan W, Fan HY, Zhang S, Zhang YL. CRL4 DCAF13 E3 ubiquitin ligase targets MeCP2 for degradation to prevent DNA hypermethylation and ensure normal transcription in growing oocytes. Cell Mol Life Sci 2024; 81:165. [PMID: 38578457 PMCID: PMC10997554 DOI: 10.1007/s00018-024-05185-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2023] [Revised: 02/23/2024] [Accepted: 02/27/2024] [Indexed: 04/06/2024]
Abstract
The DNA methylation is gradually acquired during oogenesis, a process sustained by successful follicle development. However, the functional roles of methyl-CpG-binding protein 2 (MeCP2), an epigenetic regulator displaying specifical binding with methylated DNA, remains unknown in oogenesis. In this study, we found MeCP2 protein was highly expressed in primordial and primary follicle, but was almost undetectable in secondary follicles. However, in aged ovary, MeCP2 protein is significantly increased in both oocyte and granulosa cells. Overexpression of MeCP2 in growing oocyte caused transcription dysregulation, DNA hypermethylation, and genome instability, ultimately leading to follicle growth arrest and apoptosis. MeCP2 is targeted by DCAF13, a substrate recognition adaptor of the Cullin 4-RING (CRL4) E3 ligase, and polyubiquitinated for degradation in both cells and oocytes. Dcaf13-null oocyte exhibited an accumulation of MeCP2 protein, and the partial rescue of follicle growth arrest induced by Dcaf13 deletion was observed following MeCP2 knockdown. The RNA-seq results revealed that large amounts of genes were regulated by the DCAF13-MeCP2 axis in growing oocytes. Our study demonstrated that CRL4DCAF13 E3 ubiquitin ligase targets MeCP2 for degradation to ensure normal DNA methylome and transcription in growing oocytes. Moreover, in aged ovarian follicles, deceased DCAF13 and DDB1 protein were observed, indicating a potential novel mechanism that regulates ovary aging.
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Affiliation(s)
- Peipei Ren
- Assisted Reproduction Unit, Department of Obstetrics and Gynecology, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, 310016, China
- Key Laboratory of Reproductive Dysfunction Management of Zhejiang Province, Hangzhou, China
| | - Xiaomei Tong
- Assisted Reproduction Unit, Department of Obstetrics and Gynecology, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, 310016, China
- Key Laboratory of Reproductive Dysfunction Management of Zhejiang Province, Hangzhou, China
| | - Junjian Li
- College of Life and Environmental Science, Wenzhou University, Wenzhou, China
| | - Huifang Jiang
- Assisted Reproduction Unit, Department of Obstetrics and Gynecology, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, 310016, China
- Key Laboratory of Reproductive Dysfunction Management of Zhejiang Province, Hangzhou, China
| | - Siya Liu
- Assisted Reproduction Unit, Department of Obstetrics and Gynecology, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, 310016, China
- Key Laboratory of Reproductive Dysfunction Management of Zhejiang Province, Hangzhou, China
| | - Xiang Li
- Assisted Reproduction Unit, Department of Obstetrics and Gynecology, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, 310016, China
- Key Laboratory of Reproductive Dysfunction Management of Zhejiang Province, Hangzhou, China
| | - Mengru Lai
- Assisted Reproduction Unit, Department of Obstetrics and Gynecology, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, 310016, China
- Key Laboratory of Reproductive Dysfunction Management of Zhejiang Province, Hangzhou, China
| | - Weijie Yang
- Assisted Reproduction Unit, Department of Obstetrics and Gynecology, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, 310016, China
- Key Laboratory of Reproductive Dysfunction Management of Zhejiang Province, Hangzhou, China
| | - Yan Rong
- Assisted Reproduction Unit, Department of Obstetrics and Gynecology, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, 310016, China
- Key Laboratory of Reproductive Dysfunction Management of Zhejiang Province, Hangzhou, China
| | - Yingyi Zhang
- Assisted Reproduction Unit, Department of Obstetrics and Gynecology, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, 310016, China
- Key Laboratory of Reproductive Dysfunction Management of Zhejiang Province, Hangzhou, China
| | - Jiamin Jin
- Assisted Reproduction Unit, Department of Obstetrics and Gynecology, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, 310016, China
- Key Laboratory of Reproductive Dysfunction Management of Zhejiang Province, Hangzhou, China
| | - Yerong Ma
- Assisted Reproduction Unit, Department of Obstetrics and Gynecology, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, 310016, China
- Key Laboratory of Reproductive Dysfunction Management of Zhejiang Province, Hangzhou, China
| | - Weiwei Pan
- Department of Cell Biology, College of Medicine, Jiaxing University, Jiaxing, 314001, China
| | - Heng-Yu Fan
- Key Laboratory of Reproductive Dysfunction Management of Zhejiang Province, Hangzhou, China
- Life Sciences Institute, Zhejiang University, Hangzhou, 310058, China
| | - Songying Zhang
- Assisted Reproduction Unit, Department of Obstetrics and Gynecology, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, 310016, China.
- Key Laboratory of Reproductive Dysfunction Management of Zhejiang Province, Hangzhou, China.
| | - Yin-Li Zhang
- Assisted Reproduction Unit, Department of Obstetrics and Gynecology, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, 310016, China.
- Key Laboratory of Reproductive Dysfunction Management of Zhejiang Province, Hangzhou, China.
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Nordenskiöld L, Shi X, Korolev N, Zhao L, Zhai Z, Lindman B. Liquid-liquid phase separation (LLPS) in DNA and chromatin systems from the perspective of colloid physical chemistry. Adv Colloid Interface Sci 2024; 326:103133. [PMID: 38547652 DOI: 10.1016/j.cis.2024.103133] [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: 12/29/2023] [Accepted: 03/11/2024] [Indexed: 04/13/2024]
Abstract
DNA is a highly charged polyelectrolyte and is prone to associative phase separation driven by the presence of multivalent cations, charged surfactants, proteins, polymers and colloids. The process of DNA phase separation induced by positively charged species is often called DNA condensation. Generally, it refers to either intramolecular DNA compaction (coil-globule transition) or intermolecular DNA aggregation with macroscopic phase separation, but the formation of a DNA liquid crystalline system is also displayed. This has traditionally been described by polyelectrolyte theory and qualitative (Flory-Huggins-based) polymer theory approaches. DNA in the cell nucleus is packed into chromatin wound around the histone octamer (a protein complex comprising two copies each of the four histone proteins H2A, H2B, H3 and H4) to form nucleosomes separated by linker DNA. During the last decade, the phenomenon of the formation of biomolecular condensates (dynamic droplets) by liquid-liquid phase separation (LLPS) has emerged as a generally important mechanism for the formation of membraneless organelles from proteins, nucleic acids and their complexes. DNA and chromatin droplet formation through LLPS has recently received much attention by in vitro as well as in vivo studies that established the importance of this for compartmentalisation in the cell nucleus. Here, we review DNA and chromatin LLPS from a general colloid physical chemistry perspective. We start with a general discussion of colloidal phase separation in aqueous solutions and review the original (pre-LLPS era) work on DNA (macroscopic) phase separation for simpler systems with DNA in the presence of multivalent cations and well-defined surfactants and colloids. Following that, we discuss and illustrate the similarities of such macroscopic phase separation with the general behaviour of LLPS droplet formation by associative phase separation for DNA-protein systems, including chromatin; we also note cases of segregative association. The review ends with a discussion of chromatin LLPS in vivo and its physiological significance.
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Affiliation(s)
- Lars Nordenskiöld
- School of Biological Sciences, Nanyang Technological University, Singapore 637551, Singapore.
| | - Xiangyan Shi
- Department of Biology, Shenzhen MSU-BIT University, Shenzhen 518172, China.
| | - Nikolay Korolev
- School of Biological Sciences, Nanyang Technological University, Singapore 637551, Singapore
| | - Lei Zhao
- Department of Biology, Shenzhen MSU-BIT University, Shenzhen 518172, China
| | - Ziwei Zhai
- Department of Biology, Shenzhen MSU-BIT University, Shenzhen 518172, China
| | - Björn Lindman
- School of Biological Sciences, Nanyang Technological University, Singapore 637551, Singapore; Physical Chemistry, University of Lund, P.O. Box 124, S-221 00 Lund, Sweden; Coimbra Chemistry Centre, Department of Chemistry, University of Coimbra, Rua Larga, 3004-535 Coimbra, Portugal.
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Ren Z, Gou R, Zhuo W, Chen Z, Yin X, Cao Y, Wang Y, Mi Y, Liu Y, Wang Y, Fan LM, Deng XW, Qian W. The MBD-ACD DNA methylation reader complex recruits MICRORCHIDIA6 to regulate ribosomal RNA gene expression in Arabidopsis. THE PLANT CELL 2024; 36:1098-1118. [PMID: 38092516 PMCID: PMC10980342 DOI: 10.1093/plcell/koad313] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Accepted: 12/11/2023] [Indexed: 04/01/2024]
Abstract
DNA methylation is an important epigenetic mark implicated in selective rRNA gene expression, but the DNA methylation readers and effectors remain largely unknown. Here, we report a protein complex that reads DNA methylation to regulate variant-specific 45S ribosomal RNA (rRNA) gene expression in Arabidopsis (Arabidopsis thaliana). The complex, consisting of METHYL-CpG-BINDING DOMAIN PROTEIN5 (MBD5), MBD6, ALPHA-CRYSTALLIN DOMAIN PROTEIN15.5 (ACD15.5), and ACD21.4, directly binds to 45S rDNA. While MBD5 and MBD6 function redundantly, ACD15.5 and ACD21.4 are indispensable for variant-specific rRNA gene expression. These 4 proteins undergo phase separation in vitro and in vivo and are interdependent for their phase separation. The α-crystallin domain of ACD15.5 and ACD21.4, which is essential for their function, enables phase separation of the complex, likely by mediating multivalent protein interactions. The effector MICRORCHIDIA6 directly interacts with ACD15.5 and ACD21.4, but not with MBD5 and MBD6, and is recruited to 45S rDNA by the MBD-ACD complex to regulate variant-specific 45S rRNA expression. Our study reveals a pathway in Arabidopsis through which certain 45S rRNA gene variants are silenced, while others are activated.
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Affiliation(s)
- Zhitong Ren
- National Key Laboratory of Wheat Improvement, Shandong Laboratory of Advanced Agriculture Sciences in Weifang, Peking University Institute of advanced Agricultural Sciences, Weifang, Shandong 261325, China
- College of Agronomy, Sichuan Agriculture University, Chengdu 611130, China
- School of Advanced Agricultural Sciences, Peking University, Beijing 100871, China
| | - Runyu Gou
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, Beijing 100871, China
| | - Wanqing Zhuo
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, Beijing 100871, China
| | - Zhiyu Chen
- State Key Laboratory of Genetic Engineering and Ministry of Education Key Laboratory of Biodiversity Sciences and Ecological Engineering, Institute of Plant Biology, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Xiaochang Yin
- National Key Laboratory of Wheat Improvement, Shandong Laboratory of Advanced Agriculture Sciences in Weifang, Peking University Institute of advanced Agricultural Sciences, Weifang, Shandong 261325, China
| | - Yuxin Cao
- National Key Laboratory of Wheat Improvement, Shandong Laboratory of Advanced Agriculture Sciences in Weifang, Peking University Institute of advanced Agricultural Sciences, Weifang, Shandong 261325, China
| | - Yue Wang
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, Beijing 100871, China
| | - Yingjie Mi
- National Key Laboratory of Wheat Improvement, Shandong Laboratory of Advanced Agriculture Sciences in Weifang, Peking University Institute of advanced Agricultural Sciences, Weifang, Shandong 261325, China
| | - Yannan Liu
- School of Advanced Agricultural Sciences, Peking University, Beijing 100871, China
| | - Yingxiang Wang
- State Key Laboratory of Genetic Engineering and Ministry of Education Key Laboratory of Biodiversity Sciences and Ecological Engineering, Institute of Plant Biology, School of Life Sciences, Fudan University, Shanghai 200438, China
- College of Life Sciences, Guangdong Laboratory for Lingnan Modern Agriculture, South China Agricultural University, Guangzhou, Guangdong 510642, China
| | - Liu-Min Fan
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, Beijing 100871, China
| | - Xing Wang Deng
- National Key Laboratory of Wheat Improvement, Shandong Laboratory of Advanced Agriculture Sciences in Weifang, Peking University Institute of advanced Agricultural Sciences, Weifang, Shandong 261325, China
- School of Advanced Agricultural Sciences, Peking University, Beijing 100871, China
| | - Weiqiang Qian
- National Key Laboratory of Wheat Improvement, Shandong Laboratory of Advanced Agriculture Sciences in Weifang, Peking University Institute of advanced Agricultural Sciences, Weifang, Shandong 261325, China
- School of Advanced Agricultural Sciences, Peking University, Beijing 100871, China
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9
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Tang G, Xia H, Huang Y, Guo Y, Chen Y, Ma Z, Liu W. Liquid-liquid phase separation of H3K27me3 reader BP1 regulates transcriptional repression. Genome Biol 2024; 25:67. [PMID: 38468348 PMCID: PMC10926671 DOI: 10.1186/s13059-024-03209-7] [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: 08/04/2023] [Accepted: 03/04/2024] [Indexed: 03/13/2024] Open
Abstract
BACKGROUND Bromo-adjacent homology-plant homeodomain domain containing protein 1 (BP1) is a reader of histone post-translational modifications in fungi. BP1 recognizes trimethylation of lysine 27 in histone H3 (H3K27me3), an epigenetic hallmark of gene silencing. However, whether and how BP1 participates in transcriptional repression remains poorly understood. RESULTS We report that BP1 forms phase-separated liquid condensates to modulate its biological function in Fusarium graminearum. Deletion assays reveal that intrinsically disordered region 2 (IDR2) of BP1 mediates its liquid-liquid phase separation. The phase separation of BP1 is indispensable for its interaction with suppressor of Zeste 12, a component of polycomb repressive complex 2. Furthermore, IDR2 deletion abolishes BP1-H3K27me3 binding and alleviates the transcriptional repression of secondary metabolism-related genes, especially deoxynivalenol mycotoxin biosynthesis genes. CONCLUSIONS BP1 maintains transcriptional repression by forming liquid-liquid phase-separated condensates, expanding our understanding of the relationship between post-translational modifications and liquid-liquid phase separation.
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Affiliation(s)
- Guangfei Tang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Haoxue Xia
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Yufei Huang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
- College of Plant Protection, Shenyang Agricultural University, Shenyang, 110866, China
| | - Yuanwen Guo
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Yun Chen
- State Key Laboratory of Rice Biology, Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Institute of Biotechnology, Zhejiang University, Hangzhou, 310058, China
| | - Zhonghua Ma
- State Key Laboratory of Rice Biology, Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Institute of Biotechnology, Zhejiang University, Hangzhou, 310058, China
| | - Wende Liu
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China.
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10
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Bijlani S, Pang KM, Bugga LV, Rangasamy S, Narayanan V, Chatterjee S. Nuclease-free precise genome editing corrects MECP2 mutations associated with Rett syndrome. Front Genome Ed 2024; 6:1346781. [PMID: 38495533 PMCID: PMC10940404 DOI: 10.3389/fgeed.2024.1346781] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Accepted: 02/12/2024] [Indexed: 03/19/2024] Open
Abstract
Rett syndrome is an acquired progressive neurodevelopmental disorder caused by de novo mutations in the X-linked MECP2 gene which encodes a pleiotropic protein that functions as a global transcriptional regulator and a chromatin modifier. Rett syndrome predominantly affects heterozygous females while affected male hemizygotes rarely survive. Gene therapy of Rett syndrome has proven challenging due to a requirement for stringent regulation of expression with either over- or under-expression being toxic. Ectopic expression of MECP2 in conjunction with regulatory miRNA target sequences has achieved some success, but the durability of this approach remains unknown. Here we evaluated a nuclease-free homologous recombination (HR)-based genome editing strategy to correct mutations in the MECP2 gene. The stem cell-derived AAVHSCs have previously been shown to mediate seamless and precise HR-based genome editing. We tested the ability of HR-based genome editing to correct pathogenic mutations in Exons 3 and 4 of the MECP2 gene and restore the wild type sequence while preserving all native genomic regulatory elements associated with MECP2 expression, thus potentially addressing a significant issue in gene therapy for Rett syndrome. Moreover, since the mutations are edited directly at the level of the genome, the corrections are expected to be durable with progeny cells inheriting the edited gene. The AAVHSC MECP2 editing vector was designed to be fully homologous to the target MECP2 region and to insert a promoterless Venus reporter at the end of Exon 4. Evaluation of AAVHSC editing in a panel of Rett cell lines bearing mutations in Exons 3 and 4 demonstrated successful correction and rescue of expression of the edited MECP2 gene. Sequence analysis of edited Rett cells revealed successful and accurate correction of mutations in both Exons 3 and 4 and permitted mapping of HR crossover events. Successful correction was observed only when the mutations were flanked at both the 5' and 3' ends by crossover events, but not when both crossovers occurred either exclusively upstream or downstream of the mutation. Importantly, we concluded that pathogenic mutations were successfully corrected in every Rett line analyzed, demonstrating the therapeutic potential of HR-based genome editing.
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Affiliation(s)
- Swati Bijlani
- Department of Surgery, Beckman Research Institute of the City of Hope, Duarte, CA, United States
| | - Ka Ming Pang
- Department of Surgery, Beckman Research Institute of the City of Hope, Duarte, CA, United States
| | - Lakshmi V. Bugga
- Department of Surgery, Beckman Research Institute of the City of Hope, Duarte, CA, United States
| | - Sampath Rangasamy
- Center for Rare Childhood Disorders (C4RCD), Neurogenomics Division, Translational Genomics Research Institute (TGen), Phoenix, AZ, United States
| | - Vinodh Narayanan
- Center for Rare Childhood Disorders (C4RCD), Neurogenomics Division, Translational Genomics Research Institute (TGen), Phoenix, AZ, United States
| | - Saswati Chatterjee
- Department of Surgery, Beckman Research Institute of the City of Hope, Duarte, CA, United States
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11
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Ji D, Shao C, Yu J, Hou Y, Gao X, Wu Y, Wang L, Chen P. FOXA1 forms biomolecular condensates that unpack condensed chromatin to function as a pioneer factor. Mol Cell 2024; 84:244-260.e7. [PMID: 38101414 DOI: 10.1016/j.molcel.2023.11.020] [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: 06/12/2023] [Revised: 09/14/2023] [Accepted: 11/15/2023] [Indexed: 12/17/2023]
Abstract
Eukaryotic DNA is packaged into chromatin in the nucleus, restricting the binding of transcription factors (TFs) to their target DNA sites. FOXA1 functions as a pioneer TF to bind condensed chromatin and initiate the opening of local chromatin for gene expression. However, the principles of FOXA1 recruitment and how it subsequently unpacks the condensed chromatin remain elusive. Here, we revealed that FOXA1 intrinsically forms submicron-sized condensates through its N- and C-terminal intrinsically disordered regions (IDRs). Notably, both IDRs enable FOXA1 to dissolve the condensed chromatin. In addition, the DNA-binding capacity of FOXA1 contributes to its ability to both form condensates and dissolve condensed chromatin. Further genome-wide investigation showed that IDRs enable FOXA1 to bind and unpack the condensed chromatin to regulate the proliferation and migration of breast cancer cells. This work provides a principle of how pioneer TFs function to initiate competent chromatin states using their IDRs.
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Affiliation(s)
- Dengyu Ji
- Department of Immunology, School of Basic Medical Sciences, Beijing Key Laboratory for Tumor Invasion and Metastasis, Capital Medical University, Beijing 100069, China
| | - Changrong Shao
- Department of Immunology, School of Basic Medical Sciences, Beijing Key Laboratory for Tumor Invasion and Metastasis, Capital Medical University, Beijing 100069, China
| | - Juan Yu
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Yaoyao Hou
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China; Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan 430079, China
| | - Xiao Gao
- Department of Immunology, School of Basic Medical Sciences, Beijing Key Laboratory for Tumor Invasion and Metastasis, Capital Medical University, Beijing 100069, China
| | - Yichuan Wu
- Department of Immunology, School of Basic Medical Sciences, Beijing Key Laboratory for Tumor Invasion and Metastasis, Capital Medical University, Beijing 100069, China
| | - Liang Wang
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China; Beijing Frontier Research Center for Biological Structure, School of Life Sciences, Tsinghua University, Beijing 100084, China.
| | - Ping Chen
- Department of Immunology, School of Basic Medical Sciences, Beijing Key Laboratory for Tumor Invasion and Metastasis, Capital Medical University, Beijing 100069, China; National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China.
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12
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Yang L, Lyu J, Li X, Guo G, Zhou X, Chen T, Lin Y, Li T. Phase separation as a possible mechanism for dosage sensitivity. Genome Biol 2024; 25:17. [PMID: 38225666 PMCID: PMC10789095 DOI: 10.1186/s13059-023-03128-z] [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: 04/04/2023] [Accepted: 11/27/2023] [Indexed: 01/17/2024] Open
Abstract
BACKGROUND Deletion of haploinsufficient genes or duplication of triplosensitive ones results in phenotypic effects in a concentration-dependent manner, and the mechanisms underlying these dosage-sensitive effects remain elusive. Phase separation drives functional compartmentalization of biomolecules in a concentration-dependent manner as well, which suggests a potential link between these two processes, and warrants further systematic investigation. RESULTS Here we provide bioinformatic and experimental evidence to show a close link between phase separation and dosage sensitivity. We first demonstrate that haploinsufficient or triplosensitive gene products exhibit a higher tendency to undergo phase separation. Assessing the well-established dosage-sensitive genes HNRNPK, PAX6, and PQBP1 with experiments, we show that these proteins undergo phase separation. Critically, pathogenic variations in dosage-sensitive genes disturb the phase separation process either through reduced protein levels, or loss of phase-separation-prone regions. Analysis of multi-omics data further demonstrates that loss-of-function genetic perturbations on phase-separating genes cause similar dysfunction phenotypes as dosage-sensitive gene perturbations. In addition, dosage-sensitive scores derived from population genetics data predict phase-separating proteins with much better performance than available sequence-based predictors, further illustrating close ties between these two parameters. CONCLUSIONS Together, our study shows that phase separation is functionally linked to dosage sensitivity and provides novel insights for phase-separating protein prediction from the perspective of population genetics data.
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Affiliation(s)
- Liang Yang
- Department of Medical Bioinformatics, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, 100191, China
| | - Jiali Lyu
- IDG/McGovern Institute for Brain Research, Tsinghua-Peking Joint Centre for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Xi Li
- IDG/McGovern Institute for Brain Research, Tsinghua-Peking Joint Centre for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Gaigai Guo
- Department of Medical Bioinformatics, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, 100191, China
| | - Xueya Zhou
- Department of Systems Biology, Columbia University, New York, NY, 10032, USA
| | - Taoyu Chen
- Department of Medical Bioinformatics, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, 100191, China
| | - Yi Lin
- IDG/McGovern Institute for Brain Research, Tsinghua-Peking Joint Centre for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, 100084, China.
| | - Tingting Li
- Department of Medical Bioinformatics, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, 100191, China.
- Key Laboratory for Neuroscience, Ministry of Education/National Health Commission of China, Peking University, Beijing, 100191, China.
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13
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Gorsheneva NA, Sopova JV, Azarov VV, Grizel AV, Rubel AA. Biomolecular Condensates: Structure, Functions, Methods of Research. BIOCHEMISTRY. BIOKHIMIIA 2024; 89:S205-S223. [PMID: 38621751 DOI: 10.1134/s0006297924140116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Revised: 10/12/2023] [Accepted: 10/16/2023] [Indexed: 04/17/2024]
Abstract
The term "biomolecular condensates" is used to describe membraneless compartments in eukaryotic cells, accumulating proteins and nucleic acids. Biomolecular condensates are formed as a result of liquid-liquid phase separation (LLPS). Often, they demonstrate properties of liquid-like droplets or gel-like aggregates; however, some of them may appear to have a more complex structure and high-order organization. Membraneless microcompartments are involved in diverse processes both in cytoplasm and in nucleus, among them ribosome biogenesis, regulation of gene expression, cell signaling, and stress response. Condensates properties and structure could be highly dynamic and are affected by various internal and external factors, e.g., concentration and interactions of components, solution temperature, pH, osmolarity, etc. In this review, we discuss variety of biomolecular condensates and their functions in live cells, describe their structure variants, highlight domain and primary sequence organization of the constituent proteins and nucleic acids. Finally, we describe current advances in methods that characterize structure, properties, morphology, and dynamics of biomolecular condensates in vitro and in vivo.
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Affiliation(s)
| | - Julia V Sopova
- St. Petersburg State University, St. Petersburg, 199034, Russia.
| | | | - Anastasia V Grizel
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA 30332, USA.
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14
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Kalani L, Kim BH, Vincent JB, Ausió J. MeCP2 ubiquitination and sumoylation, in search of a function†. Hum Mol Genet 2023; 33:1-11. [PMID: 37694858 DOI: 10.1093/hmg/ddad150] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Revised: 09/06/2023] [Accepted: 09/07/2023] [Indexed: 09/12/2023] Open
Abstract
MeCP2 (Methyl CpG binding protein 2) is an intrinsically disordered protein that binds to methylated genome regions. The protein is a critical transcriptional regulator of the brain, and its mutations account for 95% of Rett syndrome (RTT) cases. Early studies of this neurodevelopmental disorder revealed a close connection with dysregulations of the ubiquitin system (UbS), notably as related to UBE3A, a ubiquitin ligase involved in the proteasome-mediated degradation of proteins. MeCP2 undergoes numerous post-translational modifications (PTMs), including ubiquitination and sumoylation, which, in addition to the potential functional outcomes of their monomeric forms in gene regulation and synaptic plasticity, in their polymeric organization, these modifications play a critical role in proteasomal degradation. UbS-mediated proteasomal degradation is crucial in maintaining MeCP2 homeostasis for proper function and is involved in decreasing MeCP2 in some RTT-causing mutations. However, regardless of all these connections to UbS, the molecular details involved in the signaling of MeCP2 for its targeting by the ubiquitin-proteasome system (UPS) and the functional roles of monomeric MeCP2 ubiquitination and sumoylation remain largely unexplored and are the focus of this review.
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Affiliation(s)
- Ladan Kalani
- Department of Biochemistry and Microbiology, University of Victoria, 3800 Finnerty Rd, Victoria, BC V8W 2Y2, Canada
| | - Bo-Hyun Kim
- Department of Biochemistry and Microbiology, University of Victoria, 3800 Finnerty Rd, Victoria, BC V8W 2Y2, Canada
| | - John B Vincent
- Molecular Neuropsychiatry & Development (MiND) Lab, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, 250 College St, Toronto, ON M5T 1R8, Canada
- Institute of Medical Science, University of Toronto, 27 King's College Cir, Toronto, ON M5S 1A8, Canada
| | - Juan Ausió
- Department of Biochemistry and Microbiology, University of Victoria, 3800 Finnerty Rd, Victoria, BC V8W 2Y2, Canada
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15
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Liu S, Zheng P, Wang CY, Jia BB, Zemke NR, Ren B, Zhuang X. Cell-type-specific 3D-genome organization and transcription regulation in the brain. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.04.570024. [PMID: 38105994 PMCID: PMC10723369 DOI: 10.1101/2023.12.04.570024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2023]
Abstract
3D organization of the genome plays a critical role in regulating gene expression. However, it remains unclear how chromatin organization differs among different cell types in the brain. Here we used genome-scale DNA and RNA imaging to investigate 3D-genome organization in transcriptionally distinct cell types in the primary motor cortex of the mouse brain. We uncovered a wide spectrum of differences in the nuclear architecture and 3D-genome organization among different cell types, ranging from the physical size of the cell nucleus to the active-inactive chromatin compartmentalization and radial positioning of chromatin loci within the nucleus. These cell-type-dependent variations in nuclear architecture and chromatin organization exhibited strong correlation with both total transcriptional activity of the cell and transcriptional regulation of cell-type-specific marker genes. Moreover, we found that the methylated-DNA-binding protein MeCP2 regulates transcription in a divergent manner, depending on the nuclear radial positions of chromatin loci, through modulating active-inactive chromatin compartmentalization.
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Affiliation(s)
- Shiwei Liu
- Howard Hughes Medical Institute, Department of Chemistry and Chemical Biology, Department of Physics, Harvard University, Cambridge, MA, USA
| | - Pu Zheng
- Howard Hughes Medical Institute, Department of Chemistry and Chemical Biology, Department of Physics, Harvard University, Cambridge, MA, USA
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA, USA
| | - Cosmos Yuqi Wang
- Howard Hughes Medical Institute, Department of Chemistry and Chemical Biology, Department of Physics, Harvard University, Cambridge, MA, USA
| | - Bojing Blair Jia
- Bioinformatics and Systems Biology Graduate Program, Medical Scientist Training Program, University of California San Diego, La Jolla, CA, USA
| | - Nathan R. Zemke
- Department of Cellular and Molecular Medicine and Center for Epigenomics, University of California, San Diego School of Medicine, La Jolla, CA, USA
| | - Bing Ren
- Department of Cellular and Molecular Medicine and Center for Epigenomics, University of California, San Diego School of Medicine, La Jolla, CA, USA
| | - Xiaowei Zhuang
- Howard Hughes Medical Institute, Department of Chemistry and Chemical Biology, Department of Physics, Harvard University, Cambridge, MA, USA
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16
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Abstract
The eukaryotic nucleus displays a variety of membraneless compartments with distinct biomolecular composition and specific cellular activities. Emerging evidence indicates that protein-based liquid-liquid phase separation (LLPS) plays an essential role in the formation and dynamic regulation of heterochromatin compartmentalization. This feature is especially conspicuous at the pericentric heterochromatin domains. In this review, we will describe our understanding of heterochromatin organization and LLPS. In addition, we will highlight the increasing importance of multivalent weak homo- and heteromolecular interactions in LLPS-mediated heterochromatin compartmentalization in the complex environment inside living cells.
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Affiliation(s)
- Hui Zhang
- Cell Biology and Epigenetics, Department of Biology, Technical University of Darmstadt, Darmstadt, Germany
| | - Weihua Qin
- Human Biology and Bioimaging, Faculty of Biology, Ludwig Maximilians University Munich, Planegg-Martinsried, Germany
| | - Hector Romero
- Cell Biology and Epigenetics, Department of Biology, Technical University of Darmstadt, Darmstadt, Germany
| | - Heinrich Leonhardt
- Human Biology and Bioimaging, Faculty of Biology, Ludwig Maximilians University Munich, Planegg-Martinsried, Germany
| | - M. Cristina Cardoso
- Cell Biology and Epigenetics, Department of Biology, Technical University of Darmstadt, Darmstadt, Germany,CONTACT M. Cristina Cardoso Cell Biology and Epigenetics, Department of Biology, Technical University of Darmstadt, Schnittspahnstr. 10, 64287Darmstadt, Germany
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17
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Cai L, Wang GG. Through the lens of phase separation: intrinsically unstructured protein and chromatin looping. Nucleus 2023; 14:2179766. [PMID: 36821650 PMCID: PMC9980480 DOI: 10.1080/19491034.2023.2179766] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2023] Open
Abstract
The establishment, maintenance and dynamic regulation of three-dimensional (3D) chromatin structures provide an important means for partitioning of genome into functionally distinctive domains, which helps to define specialized gene expression programs associated with developmental stages and cell types. Increasing evidence supports critical roles for intrinsically disordered regions (IDRs) harbored within transcription factors (TFs) and chromatin-modulatory proteins in inducing phase separation, a phenomenon of forming membrane-less condensates through partitioning of biomolecules. Such a process is also critically involved in the establishment of high-order chromatin structures and looping. IDR- and phase separation-driven 3D genome (re)organization often goes wrong in disease such as cancer. This review discusses about recent advances in understanding how phase separation of intrinsically disordered proteins (IDPs) modulates chromatin looping and gene expression.
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Affiliation(s)
- Ling Cai
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC, USA,Department of Genetics, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC, USA,Ling Cai Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC27599, USA
| | - Gang Greg Wang
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC, USA,Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC, USA,Department of Pharmacology, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC, USA,CONTACT Gang Greg Wang Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC27599, USA
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18
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Siqueira E, Kim BH, Reser L, Chow R, Delaney K, Esteller M, Ross MM, Shabanowitz J, Hunt DF, Guil S, Ausió J. Analysis of the interplay between MeCP2 and histone H1 during in vitro differentiation of human ReNCell neural progenitor cells. Epigenetics 2023; 18:2276425. [PMID: 37976174 PMCID: PMC10769555 DOI: 10.1080/15592294.2023.2276425] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Accepted: 10/18/2023] [Indexed: 11/19/2023] Open
Abstract
An immortalized neural cell line derived from the human ventral mesencephalon, called ReNCell, and its MeCP2 knock out were used. With it, we characterized the chromatin compositional transitions undergone during differentiation, with special emphasis on linker histones. While the WT cells displayed the development of dendrites and axons the KO cells did not, despite undergoing differentiation as monitored by NeuN. ReNCell expressed minimal amounts of histone H1.0 and their linker histone complement consisted mainly of histone H1.2, H1.4 and H1.5. The overall level of histone H1 exhibited a trend to increase during the differentiation of MeCP2 KO cells. The phosphorylation levels of histone H1 proteins decreased dramatically during ReNCell's cell differentiation independently of the presence of MeCP2. Immunofluorescence analysis showed that MeCP2 exhibits an extensive co-localization with linker histones. Interestingly, the average size of the nucleus decreased during differentiation but in the MeCP2 KO cells, the smaller size of the nuclei at the start of differentiation increased by almost 40% after differentiation by 8 days (8 DIV). In summary, our data provide a compelling perspective on the dynamic changes of H1 histones during neural differentiation, coupled with the intricate interplay between H1 variants and MeCP2.Abbreviations: ACN, acetonitrile; A230, absorbance at 230 nm; bFGF, basic fibroblast growth factor; CM, chicken erythrocyte histone marker; CNS, central nervous system; CRISPR, clustered regulated interspaced short palindromic repeatsDAPI, 4,'6-diaminidino-2-phenylindole; DIV, days in vitro (days after differentiation is induced); DMEM, Dulbecco's modified Eagle medium; EGF, epidermal growth factor; ESC, embryonic stem cell; GAPDH, glyceraldehyde-3-phosphate dehydrogenase; GFAP, glial fibrillary acidic proteinHPLC, high-performance liquid chromatography; IF, immunofluorescence; iPSCs, induced pluripotent stem cells; MAP2, microtubule-associated protein 2; MBD, methyl-binding domain; MeCP2, methyl-CpG binding protein 2; MS, mass spectrometry; NCP, nucleosome core particle; NeuN, neuron nuclear antigen; NPC, neural progenitor cellPAGE, polyacrylamide gel electrophoresis; PBS, phosphate buffered saline; PFA, paraformaldehyde; PTM, posttranslational modification; RP-HPLC, reversed phase HPLC; ReNCells, ReNCells VM; RPLP0, ribosomal protein lateral stalk subunit P0; RT-qPCR, reverse transcription quantitative polymerase-chain reaction; RTT, Rett Syndrome; SDS, sodium dodecyl sulphate; TAD, topologically associating domain; Triple KO, triple knockout.
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Affiliation(s)
- Edilene Siqueira
- Josep Carreras Leukaemia Research Institute (IJC), Badalona, Barcelona, Catalonia, Spain
- National Council for Scientific and Technological Development (CNPq), Brasilia, Federal District, Brazil
| | - Bo-Hyun Kim
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC, Canada
| | - Larry Reser
- Department of Chemistry, University of Virginia, Charlottesville, Virginia, USA
| | - Robert Chow
- Department of Biology, University of Victoria, Victoria, BC, Canada
| | - Kerry Delaney
- Department of Biology, University of Victoria, Victoria, BC, Canada
| | - Manel Esteller
- Josep Carreras Leukaemia Research Institute (IJC), Badalona, Barcelona, Catalonia, Spain
- Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Catalonia, Spain
- Physiological Sciences Department, School of Medicine and Health Sciences, University of Barcelona (UB), Barcelona, Catalonia, Spain
| | - Mark M. Ross
- Department of Chemistry, University of Virginia, Charlottesville, Virginia, USA
| | - Jeffrey Shabanowitz
- Department of Chemistry, University of Virginia, Charlottesville, Virginia, USA
| | - Donald F. Hunt
- Department of Chemistry, University of Virginia, Charlottesville, Virginia, USA
- Department of Pathology, University of Virginia, Charlottesville, Virginia, USA
| | - Sonia Guil
- Josep Carreras Leukaemia Research Institute (IJC), Badalona, Barcelona, Catalonia, Spain
- GermansTrias i Pujol Health Science Research Institute, Badalona, Barcelona, Catalonia, Spain
| | - Juan Ausió
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC, Canada
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19
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Lu G, Li P. PHF1 compartmentalizes PRC2 via phase separation. Biochem J 2023; 480:1833-1844. [PMID: 37888776 DOI: 10.1042/bcj20230040] [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: 02/25/2023] [Revised: 10/25/2023] [Accepted: 10/26/2023] [Indexed: 10/28/2023]
Abstract
Polycomb repressive complex 2 (PRC2) is central to polycomb repression as it trimethylates lysine 27 on histone H3 (H3K27me3). How PRC2 is recruited to its targets to deposit H3K27me3 remains an open question. Polycomb-like (PCL) proteins, a group of conserved PRC2 accessory proteins, can direct PRC2 to its targets. In this report, we demonstrate that a PCL protein named PHF1 forms phase-separated condensates at H3K27me3 loci that recruit PRC2. Combining cellular observation and biochemical reconstitution, we show that the N-terminal domains of PHF1 cooperatively mediate target recognition, the chromo-like domain recruits PRC2, and the intrinsically disordered region (IDR) drives phase separation. Moreover, we reveal that the condensates compartmentalize PRC2, DNA, and nucleosome arrays by phase separation. Luciferase reporter assays confirm that PHF1 phase separation promotes transcription repression, further supporting a role of the condensates in polycomb repression. Based on our findings, we propose that these condensates create favorable microenvironments at the target loci for PRC2 to function.
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Affiliation(s)
- Genzhe Lu
- Beijing Frontier Research Center for Biological Structure, School of Life Sciences, Tsinghua University, Beijing 100084, China
- Tsinghua-Peking Joint Center for Life Sciences, Beijing 100084, China
- Tsinghua Xuetang Life Science Program, Tsinghua University, Beijing 100084, China
| | - Pilong Li
- Beijing Frontier Research Center for Biological Structure, School of Life Sciences, Tsinghua University, Beijing 100084, China
- Tsinghua-Peking Joint Center for Life Sciences, Beijing 100084, China
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20
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Yan K, Ji Q, Zhao D, Li M, Sun X, Wang Z, Liu X, Liu Z, Li H, Ding Y, Wang S, Belmonte JCI, Qu J, Zhang W, Liu GH. SGF29 nuclear condensates reinforce cellular aging. Cell Discov 2023; 9:110. [PMID: 37935676 PMCID: PMC10630320 DOI: 10.1038/s41421-023-00602-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Accepted: 09/07/2023] [Indexed: 11/09/2023] Open
Abstract
Phase separation, a biophysical segregation of subcellular milieus referred as condensates, is known to regulate transcription, but its impacts on physiological processes are less clear. Here, we demonstrate the formation of liquid-like nuclear condensates by SGF29, a component of the SAGA transcriptional coactivator complex, during cellular senescence in human mesenchymal progenitor cells (hMPCs) and fibroblasts. The Arg 207 within the intrinsically disordered region is identified as the key amino acid residue for SGF29 to form phase separation. Through epigenomic and transcriptomic analysis, our data indicated that both condensate formation and H3K4me3 binding of SGF29 are essential for establishing its precise chromatin location, recruiting transcriptional factors and co-activators to target specific genomic loci, and initiating the expression of genes associated with senescence, such as CDKN1A. The formation of SGF29 condensates alone, however, may not be sufficient to drive H3K4me3 binding or achieve transactivation functions. Our study establishes a link between phase separation and aging regulation, highlighting nuclear condensates as a functional unit that facilitate shaping transcriptional landscapes in aging.
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Affiliation(s)
- Kaowen Yan
- State Key Laboratory of Membrane Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
- Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing, China
- Beijing Institute for Stem Cell and Regenerative Medicine, Beijing, China
| | - Qianzhao Ji
- State Key Laboratory of Membrane Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Dongxin Zhao
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - Mingheng Li
- University of Chinese Academy of Sciences, Beijing, China
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Xiaoyan Sun
- University of Chinese Academy of Sciences, Beijing, China
- CAS Key Laboratory of Genomic and Precision Medicine, Beijing Institute of Genomics, Chinese Academy of Sciences and China National Center for Bioinformation, Beijing, China
| | - Zehua Wang
- University of Chinese Academy of Sciences, Beijing, China
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Xiaoqian Liu
- University of Chinese Academy of Sciences, Beijing, China
- Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing, China
- Beijing Institute for Stem Cell and Regenerative Medicine, Beijing, China
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Zunpeng Liu
- University of Chinese Academy of Sciences, Beijing, China
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Hongyu Li
- University of Chinese Academy of Sciences, Beijing, China
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Yingjie Ding
- University of Chinese Academy of Sciences, Beijing, China
- CAS Key Laboratory of Genomic and Precision Medicine, Beijing Institute of Genomics, Chinese Academy of Sciences and China National Center for Bioinformation, Beijing, China
| | - Si Wang
- Advanced Innovation Center for Human Brain Protection, and National Clinical Research Center for Geriatric Disorders, Xuanwu Hospital Capital Medical University, Beijing, China
- Aging Translational Medicine Center, International Center for Aging and Cancer, Xuanwu Hospital, Capital Medical University, Beijing, China
| | | | - Jing Qu
- University of Chinese Academy of Sciences, Beijing, China.
- Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing, China.
- Beijing Institute for Stem Cell and Regenerative Medicine, Beijing, China.
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.
| | - Weiqi Zhang
- University of Chinese Academy of Sciences, Beijing, China.
- CAS Key Laboratory of Genomic and Precision Medicine, Beijing Institute of Genomics, Chinese Academy of Sciences and China National Center for Bioinformation, Beijing, China.
- Sino-Danish College, University of Chinese Academy of Sciences, Beijing, China.
| | - Guang-Hui Liu
- State Key Laboratory of Membrane Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.
- University of Chinese Academy of Sciences, Beijing, China.
- Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing, China.
- Beijing Institute for Stem Cell and Regenerative Medicine, Beijing, China.
- Advanced Innovation Center for Human Brain Protection, and National Clinical Research Center for Geriatric Disorders, Xuanwu Hospital Capital Medical University, Beijing, China.
- Aging Translational Medicine Center, International Center for Aging and Cancer, Xuanwu Hospital, Capital Medical University, Beijing, China.
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21
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Niekamp S, Marr SK, Oei TA, Subramanian R, Kingston RE. Modularity of PRC1 Composition and Chromatin Interaction define Condensate Properties. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.10.26.564217. [PMID: 37961190 PMCID: PMC10634914 DOI: 10.1101/2023.10.26.564217] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2023]
Abstract
Polycomb repressive complexes (PRC) play a key role in gene repression and are indispensable for proper development. Canonical PRC1 forms condensates in vitro and in cells and the ability of PRC1 to form condensates has been proposed to contribute to maintenance of repression. However, how chromatin and the various subunits of PRC1 contribute to condensation is largely unexplored. Using single-molecule imaging, we demonstrate that nucleosomal arrays and PRC1 act synergistically, reducing the critical concentration required for condensation by more than 20-fold. By reconstituting and imaging PRC1 with various subunit compositions, we find that the exact combination of PHC and CBX subunits determine the initiation, morphology, stability, and dynamics of condensates. In particular, the polymerization activity of PHC2 strongly influences condensate dynamics to promote formation of structures with distinct domains that adhere to each other but do not coalesce. Using live cell imaging, we confirmed that CBX properties are critical for condensate initiation and that PHC polymerization is important to maintain stable condensates. Together, we propose that PRC1 can fine-tune the degree and type of condensation by altering its composition which might offer important flexibility of regulatory function during different stages of development.
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22
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Kuwayama N, Kujirai T, Kishi Y, Hirano R, Echigoya K, Fang L, Watanabe S, Nakao M, Suzuki Y, Ishiguro KI, Kurumizaka H, Gotoh Y. HMGA2 directly mediates chromatin condensation in association with neuronal fate regulation. Nat Commun 2023; 14:6420. [PMID: 37828010 PMCID: PMC10570362 DOI: 10.1038/s41467-023-42094-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Accepted: 09/27/2023] [Indexed: 10/14/2023] Open
Abstract
Identification of factors that regulate chromatin condensation is important for understanding of gene regulation. High-mobility group AT-hook (HMGA) proteins 1 and 2 are abundant nonhistone chromatin proteins that play a role in many biological processes including tissue stem-progenitor cell regulation, but the nature of their protein function remains unclear. Here we show that HMGA2 mediates direct condensation of polynucleosomes and forms droplets with nucleosomes. Consistently, most endogenous HMGA2 localized to transposase 5- and DNase I-inaccessible chromatin regions, and its binding was mostly associated with gene repression, in mouse embryonic neocortical cells. The AT-hook 1 domain was necessary for chromatin condensation by HMGA2 in vitro and in cellulo, and an HMGA2 mutant lacking this domain was defective in the ability to maintain neuronal progenitors in vivo. Intrinsically disordered regions of other proteins could substitute for the AT-hook 1 domain in promoting this biological function of HMGA2. Taken together, HMGA2 may regulate neural cell fate by its chromatin condensation activity.
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Grants
- This research was supported by AMED-CREST and AMED-PRIME of the Japan Agency for Medical Research and Development (JP22gm1310004, JP22gm6110021), SECOM Science and Technology Foundation SECOM Science and Technology Foundation (for Y.K.), Platform Project for Supporting Drug Discovery and Life Science Research from AMED JP21am0101076 and (for H.K.), Research Support Project for Life Science and Drug Discovery from AMED JP22ama121009 (for H.K.), Japan Science and Technology Agency ERATO JPMJER1901 (for H.K.) and by KAKENHI grants from the Ministry of Education, Culture, Sports, Science, and Technology of Japan and the Japan Society for the Promotion of Science (JP21J14115 for N.K.; JP22K15033 for T.K.;16H06279, 20H03179, 21H00242 and 22H04687 for Y.K.; 20K07589 for S.W.; JP20H00449, JP18H05534 for H.K.; JP22H00431, JP16H06279 and JP22H04925 for Y.G.)
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Affiliation(s)
- Naohiro Kuwayama
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, 113-0033, Japan
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA
| | - Tomoya Kujirai
- Institute for Quantitative Biosciences, The University of Tokyo, Tokyo, 113-0032, Japan
| | - Yusuke Kishi
- Institute for Quantitative Biosciences, The University of Tokyo, Tokyo, 113-0032, Japan
| | - Rina Hirano
- Institute for Quantitative Biosciences, The University of Tokyo, Tokyo, 113-0032, Japan
| | - Kenta Echigoya
- Institute for Quantitative Biosciences, The University of Tokyo, Tokyo, 113-0032, Japan
| | - Lingyan Fang
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, 113-0033, Japan
| | - Sugiko Watanabe
- Institute of Molecular Embryology and Genetics, Kumamoto University, Kumamoto, 860-0811, Japan
| | - Mitsuyoshi Nakao
- Institute of Molecular Embryology and Genetics, Kumamoto University, Kumamoto, 860-0811, Japan
| | - Yutaka Suzuki
- Department of Computational Biology, Graduate School of Frontier Sciences, The University of Tokyo, Chiba, 277-8561, Japan
| | - Kei-Ichiro Ishiguro
- Institute of Molecular Embryology and Genetics, Kumamoto University, Kumamoto, 860-0811, Japan
| | - Hitoshi Kurumizaka
- Institute for Quantitative Biosciences, The University of Tokyo, Tokyo, 113-0032, Japan.
| | - Yukiko Gotoh
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, 113-0033, Japan.
- International Research Center for Neurointelligence (WPI-IRCN), The University of Tokyo, Tokyo, 113-0033, Japan.
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23
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Zhou J, Cattoglio C, Shao Y, Tirumala HP, Vetralla C, Bajikar SS, Li Y, Chen H, Wang Q, Wu Z, Tang B, Zahabiyon M, Bajic A, Meng X, Ferrie JJ, LaGrone A, Zhang P, Kim JJ, Tang J, Liu Z, Darzacq X, Heintz N, Tjian R, Zoghbi HY. A novel pathogenic mutation of MeCP2 impairs chromatin association independent of protein levels. Genes Dev 2023; 37:883-900. [PMID: 37890975 PMCID: PMC10691473 DOI: 10.1101/gad.350733.123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Accepted: 10/05/2023] [Indexed: 10/29/2023]
Abstract
Loss-of-function mutations in MECP2 cause Rett syndrome (RTT), a severe neurological disorder that mainly affects girls. Mutations in MECP2 do occur in males occasionally and typically cause severe encephalopathy and premature lethality. Recently, we identified a missense mutation (c.353G>A, p.Gly118Glu [G118E]), which has never been seen before in MECP2, in a young boy who suffered from progressive motor dysfunction and developmental delay. To determine whether this variant caused the clinical symptoms and study its functional consequences, we established two disease models, including human neurons from patient-derived iPSCs and a knock-in mouse line. G118E mutation partially reduces MeCP2 abundance and its DNA binding, and G118E mice manifest RTT-like symptoms seen in the patient, affirming the pathogenicity of this mutation. Using live-cell and single-molecule imaging, we found that G118E mutation alters MeCP2's chromatin interaction properties in live neurons independently of its effect on protein levels. Here we report the generation and characterization of RTT models of a male hypomorphic variant and reveal new insight into the mechanism by which this pathological mutation affects MeCP2's chromatin dynamics. Our ability to quantify protein dynamics in disease models lays the foundation for harnessing high-resolution single-molecule imaging as the next frontier for developing innovative therapies for RTT and other diseases.
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Affiliation(s)
- Jian Zhou
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas 77030, USA
- Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, Texas 77030, USA
| | - Claudia Cattoglio
- Department of Molecular and Cell Biology, Li Ka Shing Center for Biomedical and Health Sciences, California Institute for Regenerative Medicine (CIRM) Center of Excellence, University of California, Berkeley, Berkeley, California 94720, USA
- Howard Hughes Medical Institute, Berkeley, California 94720, USA
| | - Yingyao Shao
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas 77030, USA
- Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, Texas 77030, USA
- Program in Developmental Biology, Baylor College of Medicine, Houston, Texas 77030, USA
| | - Harini P Tirumala
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas 77030, USA
- Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, Texas 77030, USA
| | - Carlo Vetralla
- Department of Molecular and Cell Biology, Li Ka Shing Center for Biomedical and Health Sciences, California Institute for Regenerative Medicine (CIRM) Center of Excellence, University of California, Berkeley, Berkeley, California 94720, USA
- Howard Hughes Medical Institute, Berkeley, California 94720, USA
- School of Medicine and Surgery, University of Milan-Bicocca, Milano 20126, Italy
| | - Sameer S Bajikar
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas 77030, USA
- Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, Texas 77030, USA
| | - Yan Li
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas 77030, USA
- Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, Texas 77030, USA
| | - Hu Chen
- Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, Texas 77030, USA
- Department of Pediatrics, Baylor College of Medicine, Houston, Texas 77030, USA
| | - Qi Wang
- Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, Texas 77030, USA
- Department of Pediatrics, Baylor College of Medicine, Houston, Texas 77030, USA
| | - Zhenyu Wu
- Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, Texas 77030, USA
- Department of Pediatrics, Baylor College of Medicine, Houston, Texas 77030, USA
| | - Bing Tang
- Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, Texas 77030, USA
- Department of Pediatrics, Baylor College of Medicine, Houston, Texas 77030, USA
| | - Mahla Zahabiyon
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas 77030, USA
- Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, Texas 77030, USA
| | - Aleksandar Bajic
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas 77030, USA
- Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, Texas 77030, USA
| | - Xiangling Meng
- Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, Texas 77030, USA
- Department of Neuroscience, Baylor College of Medicine, Houston, Texas 77030, USA
| | - Jack J Ferrie
- Department of Molecular and Cell Biology, Li Ka Shing Center for Biomedical and Health Sciences, California Institute for Regenerative Medicine (CIRM) Center of Excellence, University of California, Berkeley, Berkeley, California 94720, USA
- Howard Hughes Medical Institute, Berkeley, California 94720, USA
| | - Anel LaGrone
- Advanced Technology Cores, Baylor College of Medicine, Houston, Texas 77030, USA
| | - Ping Zhang
- Department of Neuroscience, Baylor College of Medicine, Houston, Texas 77030, USA
| | - Jean J Kim
- Advanced Technology Cores, Baylor College of Medicine, Houston, Texas 77030, USA
- Department of Molecular and Cellular Biology, Stem Cells and Regenerative Medicine Center, Baylor College of Medicine, Houston, Texas 77030, USA
| | - Jianrong Tang
- Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, Texas 77030, USA
- Department of Pediatrics, Baylor College of Medicine, Houston, Texas 77030, USA
| | - Zhandong Liu
- Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, Texas 77030, USA
- Department of Pediatrics, Baylor College of Medicine, Houston, Texas 77030, USA
| | - Xavier Darzacq
- Department of Molecular and Cell Biology, Li Ka Shing Center for Biomedical and Health Sciences, California Institute for Regenerative Medicine (CIRM) Center of Excellence, University of California, Berkeley, Berkeley, California 94720, USA
| | - Nathaniel Heintz
- Laboratory of Molecular Biology, Howard Hughes Medical Institute, The Rockefeller University, New York, New York 10065, USA
| | - Robert Tjian
- Department of Molecular and Cell Biology, Li Ka Shing Center for Biomedical and Health Sciences, California Institute for Regenerative Medicine (CIRM) Center of Excellence, University of California, Berkeley, Berkeley, California 94720, USA
- Howard Hughes Medical Institute, Berkeley, California 94720, USA
| | - Huda Y Zoghbi
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas 77030, USA;
- Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, Texas 77030, USA
- Program in Developmental Biology, Baylor College of Medicine, Houston, Texas 77030, USA
- Department of Pediatrics, Baylor College of Medicine, Houston, Texas 77030, USA
- Department of Neuroscience, Baylor College of Medicine, Houston, Texas 77030, USA
- Howard Hughes Medical Institute, Baylor College of Medicine, Houston, Texas 77030, USA
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24
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Rastegar M, Davie JR. MeCP2 is the protector of epigenome integrity, membrane-less nuclear architecture, and stability of chromatin assembly. Epigenomics 2023; 15:1027-1031. [PMID: 37937403 DOI: 10.2217/epi-2023-0310] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2023] Open
Abstract
Tweetable abstract MeCP2 is an epigenetic factor with global impact in epigenome integrity, membrane-less nuclear architecture, and chromatin stability. Our Editorial covers recent advances on these important topics.
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Affiliation(s)
- Mojgan Rastegar
- Department of Biochemistry & Medical Genetics, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, MB, R3E 0J9, Canada
| | - James R Davie
- Department of Biochemistry & Medical Genetics, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, MB, R3E 0J9, Canada
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25
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陈 一, 凌 晓, 于 浩, 丁 俊. [Role of Liquid-Liquid Phase Separation in Cell Fate Transition and Diseases]. SICHUAN DA XUE XUE BAO. YI XUE BAN = JOURNAL OF SICHUAN UNIVERSITY. MEDICAL SCIENCE EDITION 2023; 54:857-862. [PMID: 37866939 PMCID: PMC10579061 DOI: 10.12182/20230960302] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Indexed: 10/24/2023]
Abstract
Liquid-liquid phase separation (LLPS), a novel mechanism of the organization and formation of cellular structures, plays a vital role in regulating cell fate transitions and disease pathogenesis and is gaining widespread attention. LLPS may lead to the assemblage of cellular structures with liquid-like fluidity, such as germ granules, stress granules, and nucleoli, which are classic membraneless organelles. These structures are typically formed through the high-concentration liquid aggregation of biomacromolecules driven by weak multivalent interactions. LLPS is involved in regulating various intracellular life activities and its dysregulation may cause the disruption of cellular functions, thereby contributing to the pathogenesis and development of neurodegenerative diseases, infectious diseases, cancers, etc. Herein, we summarized published findings on the LLPS dynamics of membraneless organelles in physiological and pathological cell fate transition, revealing their crucial roles in cell differentiation, development, and various pathogenic processes. This paper provides a fresh theoretical framework and potential therapeutic targets for LLPS-related studies, opening new avenues for future research.
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Affiliation(s)
- 一龙 陈
- 四川大学医学大数据中心 (成都 610041)Medical Big Data Center, Sichuan University, Chengdu 610041, China
- 四川大学华西医院 生物医学大数据中心 (成都 610041)West China Biomedical Big Data Center, West China Hospital, Sichuan University, Chengdu 610041, China
- 四川大学“医学+信息”中心 (成都 610041)Med-X Center for Informatics, Sichuan University, Chengdu 610041, China
| | - 晓茹 凌
- 四川大学医学大数据中心 (成都 610041)Medical Big Data Center, Sichuan University, Chengdu 610041, China
| | - 浩澎 于
- 四川大学医学大数据中心 (成都 610041)Medical Big Data Center, Sichuan University, Chengdu 610041, China
- 四川大学华西医院 生物医学大数据中心 (成都 610041)West China Biomedical Big Data Center, West China Hospital, Sichuan University, Chengdu 610041, China
- 四川大学“医学+信息”中心 (成都 610041)Med-X Center for Informatics, Sichuan University, Chengdu 610041, China
| | - 俊军 丁
- 四川大学医学大数据中心 (成都 610041)Medical Big Data Center, Sichuan University, Chengdu 610041, China
- 四川大学华西医院 生物医学大数据中心 (成都 610041)West China Biomedical Big Data Center, West China Hospital, Sichuan University, Chengdu 610041, China
- 四川大学“医学+信息”中心 (成都 610041)Med-X Center for Informatics, Sichuan University, Chengdu 610041, China
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26
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McGregor LA, Deckard CE, Smolen JA, Porter GM, Sczepanski JT. Thymine DNA glycosylase mediates chromatin phase separation in a DNA methylation-dependent manner. J Biol Chem 2023; 299:104907. [PMID: 37307918 PMCID: PMC10404674 DOI: 10.1016/j.jbc.2023.104907] [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: 06/07/2022] [Revised: 05/18/2023] [Accepted: 05/20/2023] [Indexed: 06/14/2023] Open
Abstract
Thymine DNA glycosylase (TDG) is an essential enzyme involved in numerous biological pathways, including DNA repair, DNA demethylation, and transcriptional activation. Despite these important functions, the mechanisms surrounding the actions and regulation of TDG are poorly understood. In this study, we demonstrate that TDG induces phase separation of DNA and nucleosome arrays under physiologically relevant conditions in vitro and show that the resulting chromatin droplets exhibited behaviors typical of phase-separated liquids, supporting a liquid-liquid phase separation model. We also provide evidence that TDG has the capacity to form phase-separated condensates in the cell nucleus. The ability of TDG to induce chromatin phase separation is dependent on its intrinsically disordered N- and C-terminal domains, which in isolation, promote the formation of chromatin-containing droplets having distinct physical properties, consistent with their unique mechanistic roles in the phase separation process. Interestingly, DNA methylation alters the phase behavior of the disordered domains of TDG and compromises formation of chromatin condensates by full-length TDG, indicating that DNA methylation regulates the assembly and coalescence of TDG-mediated condensates. Overall, our results shed new light on the formation and physical nature of TDG-mediated chromatin condensates, which have broad implications for the mechanism and regulation of TDG and its associated genomic processes.
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Affiliation(s)
- Lauren A McGregor
- Department of Chemistry, Texas A&M University, College Station, Texas, USA
| | - Charles E Deckard
- Department of Chemistry, Texas A&M University, College Station, Texas, USA
| | - Justin A Smolen
- Department of Chemistry, Texas A&M University, College Station, Texas, USA
| | - Gabriela M Porter
- Department of Chemistry, Texas A&M University, College Station, Texas, USA
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27
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Long Q, Zhou Y, Guo J, Wu H, Liu X. Multi-phase separation in mitochondrial nucleoids and eukaryotic nuclei. BIOPHYSICS REPORTS 2023; 9:113-119. [PMID: 38028151 PMCID: PMC10648231 DOI: 10.52601/bpr.2023.220018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Accepted: 02/10/2023] [Indexed: 03/28/2023] Open
Abstract
In mammalian cells, besides nuclei, mitochondria are the only semi-autonomous organelles possessing own DNA organized in the form of nucleoids. While eukaryotic nuclear DNA compaction, chromatin compartmentalization and transcription are regulated by phase separation, our recent work proposed a model of mitochondrial nucleoid self-assembly and transcriptional regulation by multi-phase separation. Herein, we summarized the phase separation both in the nucleus and mitochondrial nucleoids, and did a comparison of the organization and activity regulating, which would provide new insight into the understanding of both architecture and genetics of nucleus and mitochondrial nucleoids.
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Affiliation(s)
- Qi Long
- CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences, The Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan People’s Hospital, Guangzhou Medical University; Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou 510530, China
- Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, China-New Zealand Joint Laboratory on Biomedicine and Health, CUHK-GIBH Joint Research Laboratory on Stem Cells and Regenerative Medicine, Institute for Stem Cell and Regeneration, Institute for Stem Cell and Regeneration, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou 510530, China
| | - Yanshuang Zhou
- CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences, The Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan People’s Hospital, Guangzhou Medical University; Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou 510530, China
- Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, China-New Zealand Joint Laboratory on Biomedicine and Health, CUHK-GIBH Joint Research Laboratory on Stem Cells and Regenerative Medicine, Institute for Stem Cell and Regeneration, Institute for Stem Cell and Regeneration, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou 510530, China
| | - Jingyi Guo
- CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences, The Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan People’s Hospital, Guangzhou Medical University; Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou 510530, China
- Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, China-New Zealand Joint Laboratory on Biomedicine and Health, CUHK-GIBH Joint Research Laboratory on Stem Cells and Regenerative Medicine, Institute for Stem Cell and Regeneration, Institute for Stem Cell and Regeneration, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou 510530, China
| | - Hao Wu
- CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences, The Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan People’s Hospital, Guangzhou Medical University; Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou 510530, China
- Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, China-New Zealand Joint Laboratory on Biomedicine and Health, CUHK-GIBH Joint Research Laboratory on Stem Cells and Regenerative Medicine, Institute for Stem Cell and Regeneration, Institute for Stem Cell and Regeneration, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou 510530, China
| | - Xingguo Liu
- CAS Key Laboratory of Regenerative Biology, Joint School of Life Sciences, The Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan People’s Hospital, Guangzhou Medical University; Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou 510530, China
- Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, China-New Zealand Joint Laboratory on Biomedicine and Health, CUHK-GIBH Joint Research Laboratory on Stem Cells and Regenerative Medicine, Institute for Stem Cell and Regeneration, Institute for Stem Cell and Regeneration, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou 510530, China
- Centre for Regenerative Medicine and Health, Hong Kong Institute of Science & Innovation, Chinese Academy of Sciences, Hong Kong SAR, China
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28
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Li C, Li Z, Wu Z, Lu H. Phase separation in gene transcription control. Acta Biochim Biophys Sin (Shanghai) 2023; 55:1052-1063. [PMID: 37265348 PMCID: PMC10415188 DOI: 10.3724/abbs.2023099] [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: 03/15/2023] [Accepted: 04/28/2023] [Indexed: 06/03/2023] Open
Abstract
Phase separation provides a general mechanism for the formation of biomolecular condensates, and it plays a vital role in regulating diverse cellular processes, including gene expression. Although the role of transcription factors and coactivators in regulating transcription has long been understood, how phase separation is involved in this process is just beginning to be explored. In this review, we highlight recent advance in elucidating the molecular mechanisms and functions of transcriptional condensates in gene expression control. We discuss the different condensates formed at each stage of the transcription cycle and how they are dynamically regulated in response to diverse cellular and extracellular cues that cause rapid changes in gene expression. Furthermore, we present new findings regarding the dysregulation of transcription condensates and their implications in human diseases.
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Affiliation(s)
- Chengyu Li
- Zhejiang Provincial Key Laboratory for Cancer Molecular Cell BiologyLife Sciences InstituteZhejiang UniversityHangzhou310058China
| | - Zhuo Li
- Zhejiang Provincial Key Laboratory for Cancer Molecular Cell BiologyLife Sciences InstituteZhejiang UniversityHangzhou310058China
| | - Zhibing Wu
- Department of OncologyAffiliated Zhejiang HospitalZhejiang University School of MedicineHangzhou310058China
| | - Huasong Lu
- Zhejiang Provincial Key Laboratory for Cancer Molecular Cell BiologyLife Sciences InstituteZhejiang UniversityHangzhou310058China
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29
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Li X, An Z, Zhang W, Li F. Phase Separation: Direct and Indirect Driving Force for High-Order Chromatin Organization. Genes (Basel) 2023; 14:499. [PMID: 36833426 PMCID: PMC9956262 DOI: 10.3390/genes14020499] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2023] [Revised: 02/09/2023] [Accepted: 02/14/2023] [Indexed: 02/18/2023] Open
Abstract
The multi-level spatial chromatin organization in the nucleus is closely related to chromatin activity. The mechanism of chromatin organization and remodeling attract much attention. Phase separation describes the biomolecular condensation which is the basis for membraneless compartments in cells. Recent research shows that phase separation is a key aspect to drive high-order chromatin structure and remodeling. In addition, chromatin functional compartmentalization in the nucleus which is formed by phase separation also plays an important role in overall chromatin structure. In this review, we summarized the latest work about the role of phase separation in spatial chromatin organization, focusing on direct and indirect effects of phase separation on 3D chromatin organization and its impact on transcription regulation.
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Affiliation(s)
- Xiaoli Li
- Division of Cell, Developmental and Integrative Biology, School of Medicine, South China University of Technology, Guangzhou 510006, China
- Department of Cell Biology and Genetics, Core Facility of Developmental Biology, Chongqing Medical University, Chongqing 400016, China
| | - Ziyang An
- State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China
| | - Wenqing Zhang
- Division of Cell, Developmental and Integrative Biology, School of Medicine, South China University of Technology, Guangzhou 510006, China
| | - Feifei Li
- Division of Cell, Developmental and Integrative Biology, School of Medicine, South China University of Technology, Guangzhou 510006, China
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Engineering inducible biomolecular assemblies for genome imaging and manipulation in living cells. Nat Commun 2022; 13:7933. [PMID: 36566209 PMCID: PMC9789998 DOI: 10.1038/s41467-022-35504-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Accepted: 12/06/2022] [Indexed: 12/25/2022] Open
Abstract
Genome architecture and organization play critical roles in cell life. However, it remains largely unknown how genomic loci are dynamically coordinated to regulate gene expression and determine cell fate at the single cell level. We have developed an inducible system which allows Simultaneous Imaging and Manipulation of genomic loci by Biomolecular Assemblies (SIMBA) in living cells. In SIMBA, the human heterochromatin protein 1α (HP1α) is fused to mCherry and FRB, which can be induced to form biomolecular assemblies (BAs) with FKBP-scFv, guided to specific genomic loci by a nuclease-defective Cas9 (dCas9) or a transcriptional factor (TF) carrying tandem repeats of SunTag. The induced BAs can not only enhance the imaging signals at target genomic loci using a single sgRNA, either at repetitive or non-repetitive sequences, but also recruit epigenetic modulators such as histone methyltransferase SUV39H1 to locally repress transcription. As such, SIMBA can be applied to simultaneously visualize and manipulate, in principle, any genomic locus with controllable timing in living cells.
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31
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Ling X, Liu X, Jiang S, Fan L, Ding J. The dynamics of three-dimensional chromatin organization and phase separation in cell fate transitions and diseases. CELL REGENERATION (LONDON, ENGLAND) 2022; 11:42. [PMID: 36539553 PMCID: PMC9768101 DOI: 10.1186/s13619-022-00145-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/07/2022] [Accepted: 10/18/2022] [Indexed: 12/24/2022]
Abstract
Cell fate transition is a fascinating process involving complex dynamics of three-dimensional (3D) chromatin organization and phase separation, which play an essential role in cell fate decision by regulating gene expression. Phase separation is increasingly being considered a driving force of chromatin folding. In this review, we have summarized the dynamic features of 3D chromatin and phase separation during physiological and pathological cell fate transitions and systematically analyzed recent evidence of phase separation facilitating the chromatin structure. In addition, we discuss current advances in understanding how phase separation contributes to physical and functional enhancer-promoter contacts. We highlight the functional roles of 3D chromatin organization and phase separation in cell fate transitions, and more explorations are required to study the regulatory relationship between 3D chromatin organization and phase separation. 3D chromatin organization (shown by Hi-C contact map) and phase separation are highly dynamic and play functional roles during early embryonic development, cell differentiation, somatic reprogramming, cell transdifferentiation and pathogenetic process. Phase separation can regulate 3D chromatin organization directly, but whether 3D chromatin organization regulates phase separation remains unclear.
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Affiliation(s)
- Xiaoru Ling
- grid.12981.330000 0001 2360 039XAdvanced Medical Technology Center, The First Affiliated Hospital, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong China ,grid.12981.330000 0001 2360 039XRNA Biomedical Institute, Sun Yat-Sen Memorial Hospital, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong China ,grid.12981.330000 0001 2360 039XCenter for Stem Cell Biology and Tissue Engineering, Key Laboratory for Stem Cells and Tissue Engineering, Ministry of Education, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong China
| | - Xinyi Liu
- grid.12981.330000 0001 2360 039XAdvanced Medical Technology Center, The First Affiliated Hospital, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong China ,grid.12981.330000 0001 2360 039XRNA Biomedical Institute, Sun Yat-Sen Memorial Hospital, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong China ,grid.12981.330000 0001 2360 039XCenter for Stem Cell Biology and Tissue Engineering, Key Laboratory for Stem Cells and Tissue Engineering, Ministry of Education, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong China
| | - Shaoshuai Jiang
- grid.12981.330000 0001 2360 039XAdvanced Medical Technology Center, The First Affiliated Hospital, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong China ,grid.12981.330000 0001 2360 039XRNA Biomedical Institute, Sun Yat-Sen Memorial Hospital, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong China ,grid.12981.330000 0001 2360 039XCenter for Stem Cell Biology and Tissue Engineering, Key Laboratory for Stem Cells and Tissue Engineering, Ministry of Education, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong China
| | - Lili Fan
- grid.258164.c0000 0004 1790 3548Guangzhou Key Laboratory of Formula-Pattern of Traditional Chinese Medicine, School of Traditional Chinese Medicine, Jinan University, Guangzhou, Guangdong China
| | - Junjun Ding
- grid.12981.330000 0001 2360 039XAdvanced Medical Technology Center, The First Affiliated Hospital, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong China ,grid.12981.330000 0001 2360 039XRNA Biomedical Institute, Sun Yat-Sen Memorial Hospital, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong China ,grid.12981.330000 0001 2360 039XCenter for Stem Cell Biology and Tissue Engineering, Key Laboratory for Stem Cells and Tissue Engineering, Ministry of Education, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong China ,grid.410737.60000 0000 8653 1072Department of Histology and Embryology, School of Basic Medical Sciences, Guangzhou Medical University, Guangzhou, 511436 China ,grid.13291.380000 0001 0807 1581West China Biomedical Big Data Center, West China Hospital, Sichuan University, Chengdu, 610041 China
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Ren J, Zhang Z, Zong Z, Zhang L, Zhou F. Emerging Implications of Phase Separation in Cancer. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2022; 9:e2202855. [PMID: 36117111 PMCID: PMC9631093 DOI: 10.1002/advs.202202855] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2022] [Revised: 08/26/2022] [Indexed: 05/19/2023]
Abstract
In eukaryotic cells, biological activities are executed in distinct cellular compartments or organelles. Canonical organelles with membrane-bound structures are well understood. Cells also inherently contain versatile membrane-less organelles (MLOs) that feature liquid or gel-like bodies. A biophysical process termed liquid-liquid phase separation (LLPS) elucidates how MLOs form through dynamic biomolecule assembly. LLPS-related molecules often have multivalency, which is essential for low-affinity inter- or intra-molecule interactions to trigger phase separation. Accumulating evidence shows that LLPS concentrates and organizes desired molecules or segregates unneeded molecules in cells. Thus, MLOs have tunable functional specificity in response to environmental stimuli and metabolic processes. Aberrant LLPS is widely associated with several hallmarks of cancer, including sustained proliferative signaling, growth suppressor evasion, cell death resistance, telomere maintenance, DNA damage repair, etc. Insights into the molecular mechanisms of LLPS provide new insights into cancer therapeutics. Here, the current understanding of the emerging concepts of LLPS and its involvement in cancer are comprehensively reviewed.
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Affiliation(s)
- Jiang Ren
- School of MedicineZhejiang University City CollegeHangzhou215123China
- The Eighth Affiliated HospitalSun Yat‐sen UniversityShenzhen518033China
| | - Zhenyu Zhang
- Department of NeurosurgeryThe First Affiliated Hospital of Zhengzhou UniversityZhengzhouHenan450003China
| | - Zhi Zong
- MOE Key Laboratory of Biosystems Homeostasis & Protection and Innovation Center for Cell Signaling NetworkLife Sciences InstituteZhejiang UniversityHangzhou310058China
| | - Long Zhang
- MOE Key Laboratory of Biosystems Homeostasis & Protection and Innovation Center for Cell Signaling NetworkLife Sciences InstituteZhejiang UniversityHangzhou310058China
- International Biomed‐X Research Center, Second Affiliated Hospital of Zhejiang University School of MedicineZhejiang UniversityHangzhouChina
- Cancer CenterZhejiang UniversityHangzhou215123China
| | - Fangfang Zhou
- School of MedicineZhejiang University City CollegeHangzhou215123China
- Institutes of Biology and Medical SciencesSoochow UniversitySuzhou215123China
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Chen Q, Zhao L, Soman A, Arkhipova AY, Li J, Li H, Chen Y, Shi X, Nordenskiöld L. Chromatin Liquid-Liquid Phase Separation (LLPS) Is Regulated by Ionic Conditions and Fiber Length. Cells 2022; 11:cells11193145. [PMID: 36231107 PMCID: PMC9564186 DOI: 10.3390/cells11193145] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Revised: 09/20/2022] [Accepted: 10/02/2022] [Indexed: 11/16/2022] Open
Abstract
The dynamic regulation of the physical states of chromatin in the cell nucleus is crucial for maintaining cellular homeostasis. Chromatin can exist in solid- or liquid-like forms depending on the surrounding ions, binding proteins, post-translational modifications and many other factors. Several recent studies suggested that chromatin undergoes liquid-liquid phase separation (LLPS) in vitro and also in vivo; yet, controversial conclusions about the nature of chromatin LLPS were also observed from the in vitro studies. These inconsistencies are partially due to deviations in the in vitro buffer conditions that induce the condensation/aggregation of chromatin as well as to differences in chromatin (nucleosome array) constructs used in the studies. In this work, we present a detailed characterization of the effects of K+, Mg2+ and nucleosome fiber length on the physical state and property of reconstituted nucleosome arrays. LLPS was generally observed for shorter nucleosome arrays (15-197-601, reconstituted from 15 repeats of the Widom 601 DNA with 197 bp nucleosome repeat length) at physiological ion concentrations. In contrast, gel- or solid-like condensates were detected for the considerably longer 62-202-601 and lambda DNA (~48.5 kbp) nucleosome arrays under the same conditions. In addition, we demonstrated that the presence of reduced BSA and acetate buffer is not essential for the chromatin LLPS process. Overall, this study provides a comprehensive understanding of several factors regarding chromatin physical states and sheds light on the mechanism and biological relevance of chromatin phase separation in vivo.
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Affiliation(s)
- Qinming Chen
- School of Biological Sciences, Nanyang Technological University, Singapore 637551, Singapore; (Q.C.); (A.S.)
| | - Lei Zhao
- Department of Biology, Shenzhen MSU-BIT University, Shenzhen 518172, China; (L.Z.); (A.Y.A.); (J.L.); (H.L.); (Y.C.)
| | - Aghil Soman
- School of Biological Sciences, Nanyang Technological University, Singapore 637551, Singapore; (Q.C.); (A.S.)
| | - Anastasia Yu Arkhipova
- Department of Biology, Shenzhen MSU-BIT University, Shenzhen 518172, China; (L.Z.); (A.Y.A.); (J.L.); (H.L.); (Y.C.)
- Biological Faculty, Lomonosov Moscow State University, 119991 Moscow, Russia
| | - Jindi Li
- Department of Biology, Shenzhen MSU-BIT University, Shenzhen 518172, China; (L.Z.); (A.Y.A.); (J.L.); (H.L.); (Y.C.)
| | - Hao Li
- Department of Biology, Shenzhen MSU-BIT University, Shenzhen 518172, China; (L.Z.); (A.Y.A.); (J.L.); (H.L.); (Y.C.)
| | - Yinglu Chen
- Department of Biology, Shenzhen MSU-BIT University, Shenzhen 518172, China; (L.Z.); (A.Y.A.); (J.L.); (H.L.); (Y.C.)
| | - Xiangyan Shi
- Department of Biology, Shenzhen MSU-BIT University, Shenzhen 518172, China; (L.Z.); (A.Y.A.); (J.L.); (H.L.); (Y.C.)
- Correspondence: (X.S.); (L.N.)
| | - Lars Nordenskiöld
- School of Biological Sciences, Nanyang Technological University, Singapore 637551, Singapore; (Q.C.); (A.S.)
- Correspondence: (X.S.); (L.N.)
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Schmidt A, Frei J, Poetsch A, Chittka A, Zhang H, Aßmann C, Lehmkuhl A, Bauer UM, Nuber UA, Cardoso MC. MeCP2 heterochromatin organization is modulated by arginine methylation and serine phosphorylation. Front Cell Dev Biol 2022; 10:941493. [PMID: 36172281 PMCID: PMC9510713 DOI: 10.3389/fcell.2022.941493] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Accepted: 08/19/2022] [Indexed: 11/23/2022] Open
Abstract
Rett syndrome is a human intellectual disability disorder that is associated with mutations in the X-linked MECP2 gene. The epigenetic reader MeCP2 binds to methylated cytosines on the DNA and regulates chromatin organization. We have shown previously that MECP2 Rett syndrome missense mutations are impaired in chromatin binding and heterochromatin reorganization. Here, we performed a proteomics analysis of post-translational modifications of MeCP2 isolated from adult mouse brain. We show that MeCP2 carries various post-translational modifications, among them phosphorylation on S80 and S421, which lead to minor changes in either heterochromatin binding kinetics or clustering. We found that MeCP2 is (di)methylated on several arginines and that this modification alters heterochromatin organization. Interestingly, we identified the Rett syndrome mutation site R106 as a dimethylation site. In addition, co-expression of protein arginine methyltransferases (PRMT)1 and PRMT6 lead to a decrease of heterochromatin clustering. Altogether, we identified and validated novel modifications of MeCP2 in the brain and show that these can modulate its ability to bind as well as reorganize heterochromatin, which may play a role in the pathology of Rett syndrome.
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Affiliation(s)
- Annika Schmidt
- Cell Biology and Epigenetics, Department of Biology, Technical University of Darmstadt, Darmstadt, Germany
| | - Jana Frei
- Stem Cell and Developmental Biology, Department of Biology, Technical University of Darmstadt, Darmstadt, Germany
| | - Ansgar Poetsch
- Queen Mary School, Medical College, Nanchang University, Nanchang, China
- Plant Biochemistry, Ruhr University Bochum, Bochum, Germany
- College of Marine Life Sciences, Ocean University of China, Qingdao, China
| | - Alexandra Chittka
- Division of Medicine, The Wolfson Institute for Biomedical Research, University College London, London, United Kingdom
- Department of Neuromuscular Diseases, Queen Square Institute of Neurology, University College London, London, United Kingdom
| | - Hui Zhang
- Cell Biology and Epigenetics, Department of Biology, Technical University of Darmstadt, Darmstadt, Germany
| | - Chris Aßmann
- Institute of Molecular Biology and Tumor Research, Philipps University Marburg, Marburg, Germany
| | - Anne Lehmkuhl
- Cell Biology and Epigenetics, Department of Biology, Technical University of Darmstadt, Darmstadt, Germany
| | - Uta-Maria Bauer
- Institute of Molecular Biology and Tumor Research, Philipps University Marburg, Marburg, Germany
| | - Ulrike A. Nuber
- Stem Cell and Developmental Biology, Department of Biology, Technical University of Darmstadt, Darmstadt, Germany
- *Correspondence: Ulrike A. Nuber, ; M. Cristina Cardoso,
| | - M. Cristina Cardoso
- Cell Biology and Epigenetics, Department of Biology, Technical University of Darmstadt, Darmstadt, Germany
- *Correspondence: Ulrike A. Nuber, ; M. Cristina Cardoso,
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Xiao C, Wu G, Chen P, Gao L, Chen G, Zhang H. Phase separation in epigenetics and cancer stem cells. Front Oncol 2022; 12:922604. [PMID: 36081552 PMCID: PMC9445202 DOI: 10.3389/fonc.2022.922604] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2022] [Accepted: 07/25/2022] [Indexed: 12/12/2022] Open
Abstract
Accumulating evidence indicates that liquid–liquid phase separation (LLPS) is the basis of the formation of membrane-less compartments in cells. This biomolecular condensate represented by phase separation may influence epigenetics in cancer stem cells (CSCs), a small subpopulation of cancer cells responding to the initiation, maintenance, metastasis, and therapy resistance of cancer. Understanding the underlying biophysical principles and the specific characteristics of biocondensates would provide insights into the precise blocking of potential tumor targets, thereby fundamentally curbing tumor occurrence, recurrence and metastasis. In this review, we summarized the key phenomenon and experimental detection of phase separation and the possibility of regulating the stemness of CSCs through phase separation. We believe that the mechanism of phase separation in CSCs will open up new avenues for the mystery of tumor formation, and modulating phase separation will be a great strategy for CSC-targeted tumor therapy.
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Affiliation(s)
- Chanchan Xiao
- Department of Microbiology and Immunology, School of Medicine, Jinan University, Guangzhou, China
- Institute of Geriatric Immunology, School of Medicine, Jinan University, Guangzhou, China
- Guangdong-Hongkong-Macao Great Bay Area Geroscience Joint Laboratory (GBGJL), School of Medicine, Jinan University, Guangzhou, China
| | - Guangjie Wu
- Department of Microbiology and Immunology, School of Medicine, Jinan University, Guangzhou, China
- Institute of Geriatric Immunology, School of Medicine, Jinan University, Guangzhou, China
- Guangdong-Hongkong-Macao Great Bay Area Geroscience Joint Laboratory (GBGJL), School of Medicine, Jinan University, Guangzhou, China
| | - Pengfei Chen
- Department of Microbiology and Immunology, School of Medicine, Jinan University, Guangzhou, China
- Institute of Geriatric Immunology, School of Medicine, Jinan University, Guangzhou, China
- Guangdong-Hongkong-Macao Great Bay Area Geroscience Joint Laboratory (GBGJL), School of Medicine, Jinan University, Guangzhou, China
| | - Lijuan Gao
- Department of Microbiology and Immunology, School of Medicine, Jinan University, Guangzhou, China
- Institute of Geriatric Immunology, School of Medicine, Jinan University, Guangzhou, China
- Guangdong-Hongkong-Macao Great Bay Area Geroscience Joint Laboratory (GBGJL), School of Medicine, Jinan University, Guangzhou, China
- *Correspondence: Lijuan Gao, ; Guobing Chen, ; Hongyi Zhang,
| | - Guobing Chen
- Department of Microbiology and Immunology, School of Medicine, Jinan University, Guangzhou, China
- Institute of Geriatric Immunology, School of Medicine, Jinan University, Guangzhou, China
- Guangdong-Hongkong-Macao Great Bay Area Geroscience Joint Laboratory (GBGJL), School of Medicine, Jinan University, Guangzhou, China
- *Correspondence: Lijuan Gao, ; Guobing Chen, ; Hongyi Zhang,
| | - Hongyi Zhang
- Department of Microbiology and Immunology, School of Medicine, Jinan University, Guangzhou, China
- Institute of Geriatric Immunology, School of Medicine, Jinan University, Guangzhou, China
- Guangdong-Hongkong-Macao Great Bay Area Geroscience Joint Laboratory (GBGJL), School of Medicine, Jinan University, Guangzhou, China
- *Correspondence: Lijuan Gao, ; Guobing Chen, ; Hongyi Zhang,
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36
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Ng WS, Sielaff H, Zhao ZW. Phase Separation-Mediated Chromatin Organization and Dynamics: From Imaging-Based Quantitative Characterizations to Functional Implications. Int J Mol Sci 2022; 23:ijms23148039. [PMID: 35887384 PMCID: PMC9316379 DOI: 10.3390/ijms23148039] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Revised: 07/18/2022] [Accepted: 07/19/2022] [Indexed: 12/14/2022] Open
Abstract
As an effective and versatile strategy to compartmentalize cellular components without the need for lipid membranes, phase separation has been found to underpin a wide range of intranuclear processes, particularly those involving chromatin. Many of the unique physico-chemical properties of chromatin-based phase condensates are harnessed by the cell to accomplish complex regulatory functions in a spatially and temporally controlled manner. Here, we survey key recent findings on the mechanistic roles of phase separation in regulating the organization and dynamics of chromatin-based molecular processes across length scales, packing states and intranuclear functions, with a particular emphasis on quantitative characterizations of these condensates enabled by advanced imaging-based approaches. By illuminating the complex interplay between chromatin and various chromatin-interacting molecular species mediated by phase separation, this review sheds light on an emerging multi-scale, multi-modal and multi-faceted landscape that hierarchically regulates the genome within the highly crowded and dynamic nuclear space. Moreover, deficiencies in existing studies also highlight the need for mechanism-specific criteria and multi-parametric approaches for the characterization of chromatin-based phase separation using complementary techniques and call for greater efforts to correlate the quantitative features of these condensates with their functional consequences in close-to-native cellular contexts.
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Affiliation(s)
- Woei Shyuan Ng
- Department of Chemistry, Faculty of Science, National University of Singapore, Singapore 119543, Singapore; (W.S.N.); (H.S.)
- Centre for BioImaging Sciences (CBIS), Faculty of Science, National University of Singapore, Singapore 117557, Singapore
| | - Hendrik Sielaff
- Department of Chemistry, Faculty of Science, National University of Singapore, Singapore 119543, Singapore; (W.S.N.); (H.S.)
- Centre for BioImaging Sciences (CBIS), Faculty of Science, National University of Singapore, Singapore 117557, Singapore
| | - Ziqing Winston Zhao
- Department of Chemistry, Faculty of Science, National University of Singapore, Singapore 119543, Singapore; (W.S.N.); (H.S.)
- Centre for BioImaging Sciences (CBIS), Faculty of Science, National University of Singapore, Singapore 117557, Singapore
- Mechanobiology Institute (MBI), National University of Singapore, Singapore 117411, Singapore
- Correspondence:
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37
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Nsengimana B, Khan FA, Awan UA, Wang D, Fang N, Wei W, Zhang W, Ji S. Pseudogenes and Liquid Phase Separation in Epigenetic Expression. Front Oncol 2022; 12:912282. [PMID: 35875144 PMCID: PMC9305658 DOI: 10.3389/fonc.2022.912282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Accepted: 06/13/2022] [Indexed: 11/24/2022] Open
Abstract
Pseudogenes have been considered as non-functional genes. However, peptides and long non-coding RNAs produced by pseudogenes are expressed in different tumors. Moreover, the dysregulation of pseudogenes is associated with cancer, and their expressions are higher in tumors compared to normal tissues. Recent studies show that pseudogenes can influence the liquid phase condensates formation. Liquid phase separation involves regulating different epigenetic stages, including transcription, chromatin organization, 3D DNA structure, splicing, and post-transcription modifications like m6A. Several membrane-less organelles, formed through the liquid phase separate, are also involved in the epigenetic regulation, and their defects are associated with cancer development. However, the association between pseudogenes and liquid phase separation remains unrevealed. The current study sought to investigate the relationship between pseudogenes and liquid phase separation in cancer development, as well as their therapeutic implications.
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Affiliation(s)
- Bernard Nsengimana
- Laboratory of Cell Signal Transduction, Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Henan University, Kaifeng, China
| | - Faiz Ali Khan
- Laboratory of Cell Signal Transduction, Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Henan University, Kaifeng, China
- School of Life Sciences, Henan University, Kaifeng, China
- Department of Basic Sciences Research, Shaukat Khanum Memorial Cancer Hospital and Research Centre (SKMCH&RC), Lahore, Pakistan
| | - Usman Ayub Awan
- Department of Medical Laboratory Technology, The University of Haripur, Haripur, Pakistan
| | - Dandan Wang
- Laboratory of Cell Signal Transduction, Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Henan University, Kaifeng, China
| | - Na Fang
- Laboratory of Cell Signal Transduction, Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Henan University, Kaifeng, China
| | - Wenqiang Wei
- Laboratory of Cell Signal Transduction, Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Henan University, Kaifeng, China
- *Correspondence: Wenqiang Wei, ; Weijuan Zhang, ; Shaoping Ji,
| | - Weijuan Zhang
- Laboratory of Cell Signal Transduction, Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Henan University, Kaifeng, China
- *Correspondence: Wenqiang Wei, ; Weijuan Zhang, ; Shaoping Ji,
| | - Shaoping Ji
- Laboratory of Cell Signal Transduction, Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Henan University, Kaifeng, China
- *Correspondence: Wenqiang Wei, ; Weijuan Zhang, ; Shaoping Ji,
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38
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Phase separation of insulin receptor substrate 1 drives the formation of insulin/IGF-1 signalosomes. Cell Discov 2022; 8:60. [PMID: 35764611 PMCID: PMC9240053 DOI: 10.1038/s41421-022-00426-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Accepted: 05/27/2022] [Indexed: 11/25/2022] Open
Abstract
As a critical node for insulin/IGF signaling, insulin receptor substrate 1 (IRS-1) is essential for metabolic regulation. A long and unstructured C-terminal region of IRS-1 recruits downstream effectors for promoting insulin/IGF signals. However, the underlying molecular basis for this remains elusive. Here, we found that the C-terminus of IRS-1 undergoes liquid-liquid phase separation (LLPS). Both electrostatic and hydrophobic interactions were seen to drive IRS-1 LLPS. Self-association of IRS-1, which was mainly mediated by the 301–600 region, drives IRS-1 LLPS to form insulin/IGF-1 signalosomes. Moreover, tyrosine residues of YXXM motifs, which recruit downstream effectors, also contributed to IRS-1 self-association and LLPS. Impairment of IRS-1 LLPS attenuated its positive effects on insulin/IGF-1 signaling. The metabolic disease-associated G972R mutation impaired the self-association and LLPS of IRS-1. Our findings delineate a mechanism in which LLPS of IRS-1-mediated signalosomes serves as an organizing center for insulin/IGF-1 signaling and implicate the role of aberrant IRS-1 LLPS in metabolic diseases.
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39
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Steinkellner H, Kempaiah P, Beribisky AV, Pferschy S, Etzler J, Huber A, Sarne V, Neuhaus W, Kuttke M, Bauer J, Arunachalam JP, Christodoulou J, Dressel R, Mildner A, Prinz M, Laccone F. TAT-MeCP2 protein variants rescue disease phenotypes in human and mouse models of Rett syndrome. Int J Biol Macromol 2022; 209:972-983. [PMID: 35460749 DOI: 10.1016/j.ijbiomac.2022.04.080] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 04/08/2022] [Accepted: 04/11/2022] [Indexed: 01/02/2023]
Abstract
Rett syndrome (RTT) is a neurodevelopmental disorder caused by pathogenic variants leading to functional impairment of the MeCP2 protein. Here, we used purified recombinant MeCP2e1 and MeCP2e2 protein variants fused to a TAT protein transduction domain (PTD) to evaluate their transduction ability into RTT patient-derived fibroblasts and the ability to carry out their cellular function. We then assessed their transduction ability and therapeutic effects in a RTT mouse model. In vitro, TAT-MeCP2e2-eGFP reversed the pathological hyperacetylation of histones H3K9 and H4K16, a hallmark of abolition of MeCP2 function. In vivo, intraperitoneal administration of TAT-MeCP2e1 and TAT-MeCP2e2 extended the lifespan of Mecp2-/y mice by >50%. This was accompanied by rescue of hippocampal CA2 neuron size in animals treated with TAT-MeCP2e1. Taken together, these findings provide a strong indication that recombinant TAT-MeCP2 can reach mouse brains following peripheral injection and can ameliorate the phenotype of RTT mouse models. Thus, our study serves as a first step in the development of a potentially novel RTT therapy.
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Affiliation(s)
- Hannes Steinkellner
- Center for Pathobiochemistry and Genetics, Institute of Medical Genetics, Medical University of Vienna, 1090 Vienna, Austria
| | - Prakasha Kempaiah
- Institute for Human Genetics, Georg August University, Universitätsmedizin Göttingen, 37073 Göttingen, Germany; Division of Infectious Diseases, Mayo Clinic, Jacksonville, FL, USA
| | - Alexander V Beribisky
- Center for Pathobiochemistry and Genetics, Institute of Medical Genetics, Medical University of Vienna, 1090 Vienna, Austria
| | - Sandra Pferschy
- Center for Pathobiochemistry and Genetics, Institute of Medical Genetics, Medical University of Vienna, 1090 Vienna, Austria
| | - Julia Etzler
- Center for Pathobiochemistry and Genetics, Institute of Medical Genetics, Medical University of Vienna, 1090 Vienna, Austria
| | - Anna Huber
- Center for Pathobiochemistry and Genetics, Institute of Medical Genetics, Medical University of Vienna, 1090 Vienna, Austria; Vienna Doctoral School of Pharmaceutical, Nutritional and Sport Sciences (PhaNuSpo), University of Vienna, Althanstraße 14, 1090 Vienna, Austria
| | - Victoria Sarne
- Center for Pathobiochemistry and Genetics, Institute of Medical Genetics, Medical University of Vienna, 1090 Vienna, Austria
| | - Winfried Neuhaus
- AIT Austrian Institute of Technology GmbH, Competence Center Molecular Diagnostics, 1210 Vienna, Austria
| | - Mario Kuttke
- Institute for Vascular Biology, Center for Physiology and Pharmacology, Medical University Vienna, Vienna, Austria
| | - Jan Bauer
- Department of Neuroimmunology, Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Jayamuruga P Arunachalam
- Institute for Human Genetics, Georg August University, Universitätsmedizin Göttingen, 37073 Göttingen, Germany; Division of Infectious Diseases, Mayo Clinic, Jacksonville, FL, USA; Department of Medicine, University of Toronto, Medical Sciences Building, 1 King's College Circle, Toronto, ON, Canada
| | - John Christodoulou
- Murdoch Children's Research Institute and Department of Paediatrics, University of Melbourne, Discipline of Child & Adolescent Health, Sydney Medical School, Australia
| | - Ralf Dressel
- Department of Cellular and Molecular Immunology, Georg August University, Universitätsmedizin Göttingen, 37073 Göttingen, Germany
| | - Alexander Mildner
- Institute of Neuropathology, Medical Faculty, University of Freiburg, Freiburg, Germany; Center for Basics in NeuroModulation (NeuroModulBasics), Faculty of Medicine, University of Freiburg, Freiburg, Germany; Signalling Research Centres BIOSS and CIBSS, University of Freiburg, Freiburg, Germany
| | - Marco Prinz
- Institute of Neuropathology, Medical Faculty, University of Freiburg, Freiburg, Germany; Center for Basics in NeuroModulation (NeuroModulBasics), Faculty of Medicine, University of Freiburg, Freiburg, Germany; Signalling Research Centres BIOSS and CIBSS, University of Freiburg, Freiburg, Germany
| | - Franco Laccone
- Center for Pathobiochemistry and Genetics, Institute of Medical Genetics, Medical University of Vienna, 1090 Vienna, Austria; Institute for Human Genetics, Georg August University, Universitätsmedizin Göttingen, 37073 Göttingen, Germany; Department of Cellular and Molecular Immunology, Georg August University, Universitätsmedizin Göttingen, 37073 Göttingen, Germany.
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40
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Zhang H, Romero H, Schmidt A, Gagova K, Qin W, Bertulat B, Lehmkuhl A, Milden M, Eck M, Meckel T, Leonhardt H, Cardoso MC. MeCP2-induced heterochromatin organization is driven by oligomerization-based liquid–liquid phase separation and restricted by DNA methylation. Nucleus 2022; 13:1-34. [PMID: 35156529 PMCID: PMC8855868 DOI: 10.1080/19491034.2021.2024691] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Affiliation(s)
- Hui Zhang
- Department of Biology, Technical University of Darmstadt, Darmstadt, Germany
| | - Hector Romero
- Department of Biology, Technical University of Darmstadt, Darmstadt, Germany
| | - Annika Schmidt
- Department of Biology, Technical University of Darmstadt, Darmstadt, Germany
| | - Katalina Gagova
- Department of Biology, Technical University of Darmstadt, Darmstadt, Germany
| | - Weihua Qin
- Faculty of Biology, Ludwig Maximilians University Munich, Munich, Germany
| | - Bianca Bertulat
- Department of Biology, Technical University of Darmstadt, Darmstadt, Germany
| | - Anne Lehmkuhl
- Department of Biology, Technical University of Darmstadt, Darmstadt, Germany
| | - Manuela Milden
- Department of Biology, Technical University of Darmstadt, Darmstadt, Germany
| | - Malte Eck
- Department of Biology, Technical University of Darmstadt, Darmstadt, Germany
| | - Tobias Meckel
- Department of Chemistry, Technical University of Darmstadt, Darmstadt, Germany
| | - Heinrich Leonhardt
- Faculty of Biology, Ludwig Maximilians University Munich, Munich, Germany
| | - M. Cristina Cardoso
- Department of Biology, Technical University of Darmstadt, Darmstadt, Germany
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41
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Brändle F, Frühbauer B, Jagannathan M. Principles and functions of pericentromeric satellite DNA clustering into chromocenters. Semin Cell Dev Biol 2022; 128:26-39. [PMID: 35144860 DOI: 10.1016/j.semcdb.2022.02.005] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2022] [Revised: 02/03/2022] [Accepted: 02/03/2022] [Indexed: 12/29/2022]
Abstract
Simple non-coding tandem repeats known as satellite DNA are observed widely across eukaryotes. These repeats occupy vast regions at the centromere and pericentromere of chromosomes but their contribution to cellular function has remained incompletely understood. Here, we review the literature on pericentromeric satellite DNA and discuss its organization and functions across eukaryotic species. We specifically focus on chromocenters, DNA-dense nuclear foci that contain clustered pericentromeric satellite DNA repeats from multiple chromosomes. We first discuss chromocenter formation and the roles that epigenetic modifications, satellite DNA transcripts and sequence-specific satellite DNA-binding play in this process. We then review the newly emerging functions of chromocenters in genome encapsulation, the maintenance of cell fate and speciation. We specifically highlight how the rapid divergence of satellite DNA repeats impacts reproductive isolation between closely related species. Together, we underline the importance of this so-called 'junk DNA' in fundamental biological processes.
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Affiliation(s)
- Franziska Brändle
- Institute of Biochemistry, ETH Zürich, Otto-Stern-Weg 3, Zürich CH-8093, Switzerland
| | - Benjamin Frühbauer
- Institute of Biochemistry, ETH Zürich, Otto-Stern-Weg 3, Zürich CH-8093, Switzerland
| | - Madhav Jagannathan
- Institute of Biochemistry, ETH Zürich, Otto-Stern-Weg 3, Zürich CH-8093, Switzerland.
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42
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Hammonds EF, Harwig MC, Paintsil EA, Tillison EA, Hill RB, Morrison EA. Histone H3 and H4 tails play an important role in nucleosome phase separation. Biophys Chem 2022; 283:106767. [PMID: 35158124 PMCID: PMC8963862 DOI: 10.1016/j.bpc.2022.106767] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Revised: 01/19/2022] [Accepted: 01/24/2022] [Indexed: 11/28/2022]
Abstract
Chromatin organization and its dynamic regulation are crucial in governing the temporal and spatial accessibility of DNA for proper gene expression. Disordered chains of nucleosomes comprise the basis of eukaryotic chromatin, forming higher-level organization across a range of length scales. Models of chromatin organization involving phase separation driven by chromatin-associating proteins have been proposed. More recently, evidence has emerged that nucleosome arrays can phase separate in the absence of other protein factors, yet questions remain regarding the molecular basis of chromatin phase separation that governs this dynamic nuclear organization. Here, we break chromatin down into its most basic subunit, the nucleosome core particle, and investigate phase separation using turbidity assays in conjunction with differential interference contrast microscopy. We show that, at physiologically-relevant concentrations, this fundamental subunit of chromatin undergoes phase separation. Individually removing the H3 and H4 tails abrogates phase separation under the same conditions. Taking a reductionist approach to investigate H3 and H4 tail peptide interactions in-trans with DNA and nucleosome core particles supports the direct involvement of these tails in chromatin phase separation. These results provide insight into fundamental mechanisms underlying phase separation of chromatin, which starts at the level of the nucleosome core particle, and support that long-range inter-nucleosomal interactions are sufficient to drive phase separation at nuclear concentrations. Additionally, our data have implications for understanding crosstalk between histone tails and provide a lens through which to interpret the effect of histone post-translational modifications and sequence variants. STATEMENT OF SIGNIFICANCE: Emerging models propose that chromatin organization is based in phase separation, however, mechanisms that drive this dynamic nuclear organization are only beginning to be understood. Previous focus has been on phase separation driven by chromatin-associating proteins, but this has recently shifted to recognize a direct role of chromatin in phase separation. Here, we take a fundamental approach in understanding chromatin phase separation and present new findings that the basic subunit of chromatin, the nucleosome core particle, undergoes phase separation under physiological concentrations of nucleosome and monovalent salt. Furthermore, the histone H3 and H4 tails are involved in phase separation in a manner independent of histone-associating proteins. These data suggest that H3 and H4 tail epigenetic factors may modulate chromatin phase separation.
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Affiliation(s)
- Erin F Hammonds
- Department of Biochemistry, Medical College of Wisconsin, 8701 Watertown Plank Rd., Milwaukee, WI 53226, United States of America
| | - Megan Cleland Harwig
- Department of Biochemistry, Medical College of Wisconsin, 8701 Watertown Plank Rd., Milwaukee, WI 53226, United States of America
| | - Emeleeta A Paintsil
- Department of Biochemistry, Medical College of Wisconsin, 8701 Watertown Plank Rd., Milwaukee, WI 53226, United States of America
| | - Emma A Tillison
- Department of Biochemistry, Medical College of Wisconsin, 8701 Watertown Plank Rd., Milwaukee, WI 53226, United States of America; Medical Scientist Training Program, Medical College of Wisconsin, 8701 Watertown Plank Rd., Milwaukee, WI 53226, United States of America
| | - R Blake Hill
- Department of Biochemistry, Medical College of Wisconsin, 8701 Watertown Plank Rd., Milwaukee, WI 53226, United States of America
| | - Emma A Morrison
- Department of Biochemistry, Medical College of Wisconsin, 8701 Watertown Plank Rd., Milwaukee, WI 53226, United States of America.
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43
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Abstract
In eukaryotic cells, protein and RNA factors involved in genome activities like transcription, RNA processing, DNA replication, and repair accumulate in self-organizing membraneless chromatin subcompartments. These structures contribute to efficiently conduct chromatin-mediated reactions and to establish specific cellular programs. However, the underlying mechanisms for their formation are only partly understood. Recent studies invoke liquid-liquid phase separation (LLPS) of proteins and RNAs in the establishment of chromatin activity patterns. At the same time, the folding of chromatin in the nucleus can drive genome partitioning into spatially distinct domains. Here, the interplay between chromatin organization, chromatin binding, and LLPS is discussed by comparing and contrasting three prototypical chromatin subcompartments: the nucleolus, clusters of active RNA polymerase II, and pericentric heterochromatin domains. It is discussed how the different ways of chromatin compartmentalization are linked to transcription regulation, the targeting of soluble factors to certain parts of the genome, and to disease-causing genetic aberrations.
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Affiliation(s)
- Karsten Rippe
- Division of Chromatin Networks, German Cancer Research Center (DKFZ) and Bioquant, 69120 Heidelberg, Germany
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44
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Ito K, Takizawa T. Nuclear Architecture in the Nervous System. Results Probl Cell Differ 2022; 70:419-442. [PMID: 36348117 DOI: 10.1007/978-3-031-06573-6_15] [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] [Indexed: 06/16/2023]
Abstract
Neurons and glial cells in the nervous system exhibit different gene expression programs for neural development and function. These programs are controlled by the epigenetic regulatory layers in the nucleus. The nucleus is a well-organized subcellular organelle that includes chromatin, the nuclear lamina, and nuclear bodies. These subnuclear components operate together as epigenetic regulators of neural development and function and are collectively called the nuclear architecture. In the nervous system, dynamic rearrangement of the nuclear architecture has been observed in each cell type, especially in neurons, allowing for their specialized functions, including learning and memory formation. Although the importance of nuclear architecture has been debated for decades, the paradigm has been changing rapidly, owing to the development of new technologies. Here, we reviewed the latest studies on nuclear geometry, nuclear bodies, and heterochromatin compartments, as well as summarized recent novel insights regarding radial positioning, chromatin condensation, and chromatin interaction between genes and cis-regulatory elements.
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Affiliation(s)
- Kenji Ito
- Institute for Regenerative Medicine and Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Smilow Center for Translational Research, Philadelphia, Pennsylvania, USA
| | - Takumi Takizawa
- Department of Pediatrics, Gunma University Graduate School of Medicine, Maebashi, Japan.
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45
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Hansen JC, Maeshima K, Hendzel MJ. The solid and liquid states of chromatin. Epigenetics Chromatin 2021; 14:50. [PMID: 34717733 PMCID: PMC8557566 DOI: 10.1186/s13072-021-00424-5] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Accepted: 10/22/2021] [Indexed: 12/14/2022] Open
Abstract
The review begins with a concise description of the principles of phase separation. This is followed by a comprehensive section on phase separation of chromatin, in which we recount the 60 years history of chromatin aggregation studies, discuss the evidence that chromatin aggregation intrinsically is a physiologically relevant liquid-solid phase separation (LSPS) process driven by chromatin self-interaction, and highlight the recent findings that under specific solution conditions chromatin can undergo liquid-liquid phase separation (LLPS) rather than LSPS. In the next section of the review, we discuss how certain chromatin-associated proteins undergo LLPS in vitro and in vivo. Some chromatin-binding proteins undergo LLPS in purified form in near-physiological ionic strength buffers while others will do so only in the presence of DNA, nucleosomes, or chromatin. The final section of the review evaluates the solid and liquid states of chromatin in the nucleus. While chromatin behaves as an immobile solid on the mesoscale, nucleosomes are mobile on the nanoscale. We discuss how this dual nature of chromatin, which fits well the concept of viscoelasticity, contributes to genome structure, emphasizing the dominant role of chromatin self-interaction.
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Affiliation(s)
- Jeffrey C Hansen
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO, 80523, USA.
| | - Kazuhiro Maeshima
- Genome Dynamics Laboratory, National Institute of Genetics, and Department of Genetics, Sokendai (Graduate University for Advanced Studies), Mishima, Shizuoka, 411-8540, Japan.
| | - Michael J Hendzel
- Department of Cell Biology, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB, Canada.
- Department of Oncology, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB, Canada.
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46
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Phase separation drives the self-assembly of mitochondrial nucleoids for transcriptional modulation. Nat Struct Mol Biol 2021; 28:900-908. [PMID: 34711968 DOI: 10.1038/s41594-021-00671-w] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Accepted: 09/14/2021] [Indexed: 11/08/2022]
Abstract
Mitochondria, the only semiautonomous organelles in mammalian cells, possess a circular, double-stranded genome termed mitochondrial DNA (mtDNA). While nuclear genomic DNA compaction, chromatin compartmentalization and transcription are known to be regulated by phase separation, how the mitochondrial nucleoid, a highly compacted spherical suborganelle, is assembled and functions is unknown. Here we assembled mitochondrial nucleoids in vitro and show that mitochondrial transcription factor A (TFAM) undergoes phase separation with mtDNA to drive nucleoid self-assembly. Moreover, nucleoid droplet formation promotes recruitment of the transcription machinery via a special, co-phase separation that concentrates transcription initiation, elongation and termination factors, and retains substrates to facilitate mtDNA transcription. We propose a model of mitochondrial nucleoid self-assembly driven by phase separation, and a pattern of co-phase separation involved in mitochondrial transcriptional regulation, which orchestrates the roles of TFAM in both mitochondrial nucleoid organization and transcription.
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47
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Jiang Y, Fu X, Zhang Y, Wang SF, Zhu H, Wang WK, Zhang L, Wu P, Wong CCL, Li J, Ma J, Guan JS, Huang Y, Hui J. Rett syndrome linked to defects in forming the MeCP2/Rbfox/LASR complex in mouse models. Nat Commun 2021; 12:5767. [PMID: 34599184 PMCID: PMC8486766 DOI: 10.1038/s41467-021-26084-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Accepted: 09/13/2021] [Indexed: 01/01/2023] Open
Abstract
Rett syndrome (RTT) is a severe neurological disorder and a leading cause of intellectual disability in young females. RTT is mainly caused by mutations found in the X-linked gene encoding methyl-CpG binding protein 2 (MeCP2). Despite extensive studies, the molecular mechanism underlying RTT pathogenesis is still poorly understood. Here, we report MeCP2 as a key subunit of a higher-order multiunit protein complex Rbfox/LASR. Defective MeCP2 in RTT mouse models disrupts the assembly of the MeCP2/Rbfox/LASR complex, leading to reduced binding of Rbfox proteins to target pre-mRNAs and aberrant splicing of Nrxns and Nlgn1 critical for synaptic plasticity. We further show that MeCP2 disease mutants display defective condensate properties and fail to promote phase-separated condensates with Rbfox proteins in vitro and in cultured cells. These data link an impaired function of MeCP2 with disease mutation in splicing control to its defective properties in mediating the higher-order assembly of the MeCP2/Rbfox/LASR complex. MeCP2 mutations can cause Rett syndrome, a severe childhood neurological disorder. Here the authors show that MeCP2 mediates the higher-order assembly of a large splicing complex Rbfox/LASR, which is disrupted in the mouse models of Rett syndrome.
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Affiliation(s)
- Yan Jiang
- State Key Laboratory of Molecular Biology, Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, 200031, Shanghai, China
| | - Xing Fu
- Shanghai Center for Plant Stress Biology, Chinese Academy of Sciences, 201602, Shanghai, China
| | - Yuhan Zhang
- State Key Laboratory of Genetic Engineering, Collaborative Innovation Centre of Genetics and Development, Department of Biochemistry, Institute of Plant Biology, School of Life Sciences, Fudan University, 200438, Shanghai, China.,Department of General Surgery, Shanghai Key Laboratory of Biliary Tract Disease Research, State Key Laboratory of Oncogenes and Related Genes, Xinhua Hospital, Shanghai Jiao Tong University, 200092, Shanghai, China
| | - Shen-Fei Wang
- State Key Laboratory of Molecular Biology, Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, 200031, Shanghai, China
| | - Hong Zhu
- State Key Laboratory of Molecular Biology, Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, 200031, Shanghai, China
| | - Wei-Kang Wang
- State Key Laboratory of Molecular Biology, Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, 200031, Shanghai, China
| | - Lin Zhang
- State Key Laboratory of Cell Biology, Shanghai Key Laboratory of Molecular Andrology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, University of Chinese Academy of Sciences, 200031, Shanghai, China
| | - Ping Wu
- National Facility for Protein Science in Shanghai, Zhangjiang Lab, Shanghai Advanced Research Institute, Chinese Academy of Sciences, 201210, Shanghai, China
| | - Catherine C L Wong
- National Facility for Protein Science in Shanghai, Zhangjiang Lab, Shanghai Advanced Research Institute, Chinese Academy of Sciences, 201210, Shanghai, China.,Center for Precision Medicine Multi-Omics Research, Peking University Health Science Center, School of Basic Medical Sciences, Peking University, 100191, Beijing, China
| | - Jinsong Li
- State Key Laboratory of Cell Biology, Shanghai Key Laboratory of Molecular Andrology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, University of Chinese Academy of Sciences, 200031, Shanghai, China
| | - Jinbiao Ma
- State Key Laboratory of Genetic Engineering, Collaborative Innovation Centre of Genetics and Development, Department of Biochemistry, Institute of Plant Biology, School of Life Sciences, Fudan University, 200438, Shanghai, China
| | - Ji-Song Guan
- School of Life Science and Technology, ShanghaiTech University, 201210, Shanghai, China.,Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, 200031, Shanghai, China
| | - Ying Huang
- Department of General Surgery, Shanghai Key Laboratory of Biliary Tract Disease Research, State Key Laboratory of Oncogenes and Related Genes, Xinhua Hospital, Shanghai Jiao Tong University, 200092, Shanghai, China.
| | - Jingyi Hui
- State Key Laboratory of Molecular Biology, Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, 200031, Shanghai, China.
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48
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Lyu X, Wang J, Wang J, Yin YS, Zhu Y, Li LL, Huang S, Peng S, Xue B, Liao R, Wang SQ, Long M, Wohland T, Chua BT, Sun Y, Li P, Chen XW, Xu L, Chen FJ, Li P. A gel-like condensation of Cidec generates lipid-permeable plates for lipid droplet fusion. Dev Cell 2021; 56:2592-2606.e7. [PMID: 34508658 DOI: 10.1016/j.devcel.2021.08.015] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Revised: 05/02/2021] [Accepted: 08/17/2021] [Indexed: 10/20/2022]
Abstract
Membrane contact between intracellular organelles is important in mediating organelle communication. However, the assembly of molecular machinery at membrane contact site and its internal organization correlating with its functional activity remain unclear. Here, we demonstrate that a gel-like condensation of Cidec, a crucial protein for obesity development by facilitating lipid droplet (LD) fusion, occurs at the LD-LD contact site (LDCS) through phase separation. The homomeric interaction between the multivalent N terminus of Cidec is sufficient to promote its phase separation both in vivo and in vitro. Interestingly, Cidec condensation at LDCSs generates highly plastic and lipid-permeable fusion plates that are geometrically constrained by donor LDs. In addition, Cidec condensates are distributed unevenly in the fusion plate generating stochastic sub-compartments that may represent unique lipid passageways during LD fusion. We have thus uncovered the organization and functional significance of geometry-constrained Cidec phase separation in mediating LD fusion and lipid homeostasis.
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Affiliation(s)
- Xuchao Lyu
- State Key Laboratory of Membrane Biology and Tsinghua-Peking Center for Life Sciences, Beijing Advanced Innovation Center for Structural Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Jia Wang
- State Key Laboratory of Membrane Biology and Tsinghua-Peking Center for Life Sciences, Beijing Advanced Innovation Center for Structural Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Jianqin Wang
- State Key Laboratory of Membrane Biology and Tsinghua-Peking Center for Life Sciences, Beijing Advanced Innovation Center for Structural Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Ye-Sheng Yin
- Shanghai Key Laboratory of Metabolic Remodeling and Health, Institute of Metabolism and Integrative Biology, Department of Endocrinology and Metabolism, Zhongshan Hospital, Fudan University, Shanghai 200032, China
| | - Yun Zhu
- Biodynamic Optical Imaging Center (BIOPIC), School of Life Sciences, Peking University, Beijing 100871, China
| | - Lin-Lin Li
- State Key Laboratory of Biomembrane and Membrane Biotechnology, College of Life Sciences, Peking University, Beijing 100871, China
| | - Shuangru Huang
- Departments of Biological Sciences and Chemistry and NUS Centre for Bio-Imaging Sciences, National University of Singapore, 14 Science Drive 4, Singapore 117557, Singapore
| | - Shuang Peng
- Institute of Mechanics, Chinese Academy of Sciences, No.15 Beisihuanxi Road, Beijing 100190, China
| | - Boxin Xue
- Biodynamic Optical Imaging Center (BIOPIC), School of Life Sciences, Peking University, Beijing 100871, China
| | - Rongyu Liao
- State Key Laboratory of Membrane Biology and Tsinghua-Peking Center for Life Sciences, Beijing Advanced Innovation Center for Structural Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Shi-Qiang Wang
- State Key Laboratory of Biomembrane and Membrane Biotechnology, College of Life Sciences, Peking University, Beijing 100871, China
| | - Mian Long
- Institute of Mechanics, Chinese Academy of Sciences, No.15 Beisihuanxi Road, Beijing 100190, China
| | - Thorsten Wohland
- Departments of Biological Sciences and Chemistry and NUS Centre for Bio-Imaging Sciences, National University of Singapore, 14 Science Drive 4, Singapore 117557, Singapore
| | - Boon Tin Chua
- Shanghai Key Laboratory of Metabolic Remodeling and Health, Institute of Metabolism and Integrative Biology, Department of Endocrinology and Metabolism, Zhongshan Hospital, Fudan University, Shanghai 200032, China
| | - Yujie Sun
- Biodynamic Optical Imaging Center (BIOPIC), School of Life Sciences, Peking University, Beijing 100871, China
| | - Pilong Li
- Beijing Advanced Innovation Center for Structural Biology, Tsinghua-Peking Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Xiao-Wei Chen
- State Key Laboratory of Membrane Biology, Center for Life Sciences and Institute of Molecular Medicine, College of Future Technology, Peking University, Beijing 100101, China
| | - Li Xu
- State Key Laboratory of Membrane Biology and Tsinghua-Peking Center for Life Sciences, Beijing Advanced Innovation Center for Structural Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China; Shanghai Qi Zhi Institute, Shanghai 200030, China
| | - Feng-Jung Chen
- Shanghai Key Laboratory of Metabolic Remodeling and Health, Institute of Metabolism and Integrative Biology, Department of Endocrinology and Metabolism, Zhongshan Hospital, Fudan University, Shanghai 200032, China; Shanghai Qi Zhi Institute, Shanghai 200030, China.
| | - Peng Li
- State Key Laboratory of Membrane Biology and Tsinghua-Peking Center for Life Sciences, Beijing Advanced Innovation Center for Structural Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China; Shanghai Qi Zhi Institute, Shanghai 200030, China.
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49
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Liu X, Jiang S, Ma L, Qu J, Zhao L, Zhu X, Ding J. Time-dependent effect of 1,6-hexanediol on biomolecular condensates and 3D chromatin organization. Genome Biol 2021; 22:230. [PMID: 34404453 PMCID: PMC8369800 DOI: 10.1186/s13059-021-02455-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Accepted: 07/30/2021] [Indexed: 02/08/2023] Open
Abstract
BACKGROUND Biomolecular condensates have been implicated in multiple cellular processes. However, the global role played by condensates in 3D chromatin organization remains unclear. At present, 1,6-hexanediol (1,6-HD) is the only available tool to globally disrupt condensates, yet the conditions of 1,6-HD vary considerably between studies and may even trigger apoptosis. RESULTS In this study, we first analyzed the effects of different concentrations and treatment durations of 1,6-HD and found that short-term exposure to 1.5% 1,6-HD dissolved biomolecular condensates whereas long-term exposure caused aberrant aggregation without affecting cell viability. Based on this condition, we drew a time-resolved map of 3D chromatin organization and found that short-term treatment with 1.5% 1,6-HD resulted in reduced long-range interactions, strengthened compartmentalization, homogenized A-A interactions, B-to-A compartment switch and TAD reorganization, whereas longer exposure had the opposite effects. Furthermore, the long-range interactions between condensate-component-enriched regions were markedly weakened following 1,6-HD treatment. CONCLUSIONS In conclusion, our study finds a proper 1,6-HD condition and provides a resource for exploring the role of biomolecular condensates in 3D chromatin organization.
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Affiliation(s)
- Xinyi Liu
- RNA Biomedical Institute, Sun Yat-Sen Memorial Hospital, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, 510080, China
- Center for Stem Cell Biology and Tissue Engineering, Key Laboratory for Stem Cells and Tissue Engineering, Ministry of Education, Sun Yat-Sen University, Guangzhou, 510080, China
- Department of Cell Biology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, 510080, China
| | - Shaoshuai Jiang
- RNA Biomedical Institute, Sun Yat-Sen Memorial Hospital, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, 510080, China
- Center for Stem Cell Biology and Tissue Engineering, Key Laboratory for Stem Cells and Tissue Engineering, Ministry of Education, Sun Yat-Sen University, Guangzhou, 510080, China
- Department of Cell Biology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, 510080, China
| | - Lin Ma
- RNA Biomedical Institute, Sun Yat-Sen Memorial Hospital, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, 510080, China
- Center for Stem Cell Biology and Tissue Engineering, Key Laboratory for Stem Cells and Tissue Engineering, Ministry of Education, Sun Yat-Sen University, Guangzhou, 510080, China
- Department of Cell Biology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, 510080, China
| | - Jiale Qu
- RNA Biomedical Institute, Sun Yat-Sen Memorial Hospital, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, 510080, China
- Center for Stem Cell Biology and Tissue Engineering, Key Laboratory for Stem Cells and Tissue Engineering, Ministry of Education, Sun Yat-Sen University, Guangzhou, 510080, China
- Department of Cell Biology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, 510080, China
| | - Longying Zhao
- RNA Biomedical Institute, Sun Yat-Sen Memorial Hospital, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, 510080, China
- Center for Stem Cell Biology and Tissue Engineering, Key Laboratory for Stem Cells and Tissue Engineering, Ministry of Education, Sun Yat-Sen University, Guangzhou, 510080, China
- Department of Cell Biology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, 510080, China
| | - Xing Zhu
- RNA Biomedical Institute, Sun Yat-Sen Memorial Hospital, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, 510080, China
- Center for Stem Cell Biology and Tissue Engineering, Key Laboratory for Stem Cells and Tissue Engineering, Ministry of Education, Sun Yat-Sen University, Guangzhou, 510080, China
- Department of Cell Biology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, 510080, China
| | - Junjun Ding
- RNA Biomedical Institute, Sun Yat-Sen Memorial Hospital, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, 510080, China.
- Center for Stem Cell Biology and Tissue Engineering, Key Laboratory for Stem Cells and Tissue Engineering, Ministry of Education, Sun Yat-Sen University, Guangzhou, 510080, China.
- Department of Cell Biology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, 510080, China.
- Department of Histology and Embryology, School of Basic Medical Sciences, Guangzhou Medical University, Guangzhou, 511436, China.
- West China Biomedical Big Data Center, West China Hospital, Sichuan University, Chengdu, 610041, China.
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Mimura M, Tomita S, Sugai H, Shinkai Y, Ishihara S, Kurita R. Uncharged Components of Single-Stranded DNA Modulate Liquid-Liquid Phase Separation With Cationic Linker Histone H1. Front Cell Dev Biol 2021; 9:710729. [PMID: 34422830 PMCID: PMC8371396 DOI: 10.3389/fcell.2021.710729] [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: 05/17/2021] [Accepted: 07/14/2021] [Indexed: 11/15/2022] Open
Abstract
Liquid-liquid phase separation (LLPS) of proteins and DNAs has been recognized as a fundamental mechanism for the formation of intracellular biomolecular condensates. Here, we show the role of the constituent DNA components, i.e., the phosphate groups, deoxyribose sugars, and nucleobases, in LLPS with a polycationic peptide, linker histone H1, a known key regulator of chromatin condensation. A comparison of the phase behavior of mixtures of H1 and single-stranded DNA-based oligomers in which one or more of the constituent moieties of DNA were removed demonstrated that not only the electrostatic interactions between the anionic phosphate groups of the oligomers and the cationic residues of H1, but also the interactions involving nucleobases and deoxyriboses (i) promoted the generation of spherical liquid droplets via LLPS as well as (ii) increased the density of DNA and decreased its fluidity within the droplets under low-salt conditions. Furthermore, we found the formation of non-spherical assemblies with both mobile and immobile fractions at relatively higher concentrations of H1 for all the oligomers. The roles of the DNA components that promote phase separation and modulate droplet characteristics revealed in this study will facilitate our understanding of the formation processes of the various biomolecular condensates containing nucleic acids, such as chromatin organization.
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Affiliation(s)
- Masahiro Mimura
- Faculty of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Japan
- Health and Medical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Japan
| | - Shunsuke Tomita
- Health and Medical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Japan
| | - Hiroka Sugai
- Faculty of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Japan
- Health and Medical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Japan
| | - Yoichi Shinkai
- Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Japan
| | - Sayaka Ishihara
- Health and Medical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Japan
| | - Ryoji Kurita
- Faculty of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Japan
- Health and Medical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Japan
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