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Tan W, Park JV, Venugopal H, Lou JQ, Dias PS, Baldoni PL, Dite T, Moon KW, Keenan CR, Gurzau AD, Leis A, Yousef J, Vaibhav V, Dagley LF, Ang CS, Corso L, Davidovich C, Vervoort SJ, Smyth GK, Blewitt ME, Allan RS, Hinde E, D'Arcy S, Ryu JK, Shakeel S. MORC2 phosphorylation fine tunes its DNA compaction activity. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.27.600912. [PMID: 38979330 PMCID: PMC11230365 DOI: 10.1101/2024.06.27.600912] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/10/2024]
Abstract
Variants in the poorly characterised oncoprotein, MORC2, a chromatin remodelling ATPase, lead to defects in epigenetic regulation and DNA damage response. The C-terminal domain (CTD) of MORC2, frequently phosphorylated in DNA damage, promotes cancer progression, but its role in chromatin remodelling remains unclear. Here, we report a molecular characterisation of full-length, phosphorylated MORC2, demonstrating its preference for binding open chromatin and functioning as a DNA sliding clamp. We identified a phosphate interacting motif within the CTD that dictates ATP hydrolysis rate and cooperative DNA binding. The DNA binding impacts several structural domains within the ATPase region. We provide the first visual proof that MORC2 induces chromatin remodelling through ATP hydrolysis-dependent DNA compaction, regulated by its phosphorylation state. These findings highlight phosphorylation of MORC2 CTD as a key modulator of chromatin remodelling, presenting it as a potential therapeutic target.
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2
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Fendler NL, Ly J, Welp L, Urlaub H, Vos SM. Identification and characterization of a human MORC2 DNA binding region that is required for gene silencing. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.05.597643. [PMID: 38895295 PMCID: PMC11185635 DOI: 10.1101/2024.06.05.597643] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/21/2024]
Abstract
The eukaryotic microrchidia (MORC) protein family are DNA gyrase, Hsp90, histidine kinase, MutL (GHKL)-type ATPases involved in gene expression regulation and chromatin compaction. The molecular mechanisms underlying these activities are incompletely understood. Here we studied the full-length human MORC2 protein biochemically. We identified a DNA binding site in the C-terminus of the protein, and we observe that this region is heavily phosphorylated in cells. Phosphorylation of MORC2 reduces its affinity for DNA and appears to exclude the protein from the nucleus. We observe that DNA binding by MORC2 reduces its ATPase activity and that MORC2 can topologically entrap multiple DNA substrates between its N-terminal GHKL and C-terminal coiled coil 3 dimerization domains. Finally, we observe that the MORC2 C-terminal DNA binding region is required for gene silencing in cells. Together, our data provide a model to understand how MORC2 engages with DNA substrates to mediate gene silencing.
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Affiliation(s)
- Nikole L. Fendler
- Department of Biology, Massachusetts Institute of Technology, Building 68, 31 Ames St., Cambridge, MA 02139
| | - Jimmy Ly
- Department of Biology, Massachusetts Institute of Technology, Building 68, 31 Ames St., Cambridge, MA 02139
- Whitehead Institute for Biomedical Research, Cambridge, MA 02139
| | - Luisa Welp
- Bioanalytical Mass Spectrometry, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
- Bioanalytics Group, University Medical Center Göttingen, Department of Clinical Chemistry, Göttingen, Germany
| | - Henning Urlaub
- Bioanalytical Mass Spectrometry, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
- Bioanalytics Group, University Medical Center Göttingen, Department of Clinical Chemistry, Göttingen, Germany
| | - Seychelle M. Vos
- Department of Biology, Massachusetts Institute of Technology, Building 68, 31 Ames St., Cambridge, MA 02139
- Howard Hughes Medical Institute
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3
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Li Z, Fan H, Ding W. Solving protein structures by combining structure prediction, molecular replacement and direct-methods-aided model completion. IUCRJ 2024; 11:152-167. [PMID: 38214490 PMCID: PMC10916285 DOI: 10.1107/s2052252523010291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Accepted: 11/29/2023] [Indexed: 01/13/2024]
Abstract
Highly accurate protein structure prediction can generate accurate models of protein and protein-protein complexes in X-ray crystallography. However, the question of how to make more effective use of predicted models for completing structure analysis, and which strategies should be employed for the more challenging cases such as multi-helical structures, multimeric structures and extremely large structures, both in the model preparation and in the completion steps, remains open for discussion. In this paper, a new strategy is proposed based on the framework of direct methods and dual-space iteration, which can greatly simplify the pre-processing steps of predicted models both in normal and in challenging cases. Following this strategy, full-length models or the conservative structural domains could be used directly as the starting model, and the phase error and the model bias between the starting model and the real structure would be modified in the direct-methods-based dual-space iteration. Many challenging cases (from CASP14) have been tested for the general applicability of this constructive strategy, and almost complete models have been generated with reasonable statistics. The hybrid strategy therefore provides a meaningful scheme for X-ray structure determination using a predicted model as the starting point.
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Affiliation(s)
- Zengru Li
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People’s Republic of China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, People’s Republic of China
| | - Haifu Fan
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People’s Republic of China
| | - Wei Ding
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People’s Republic of China
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4
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Keniry A, Blewitt ME. Chromatin-mediated silencing on the inactive X chromosome. Development 2023; 150:dev201742. [PMID: 37991053 DOI: 10.1242/dev.201742] [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: 11/23/2023]
Abstract
In mammals, the second X chromosome in females is silenced to enable dosage compensation between XX females and XY males. This essential process involves the formation of a dense chromatin state on the inactive X (Xi) chromosome. There is a wealth of information about the hallmarks of Xi chromatin and the contribution each makes to silencing, leaving the tantalising possibility of learning from this knowledge to potentially remove silencing to treat X-linked diseases in females. Here, we discuss the role of each chromatin feature in the establishment and maintenance of the silent state, which is of crucial relevance for such a goal.
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Affiliation(s)
- Andrew Keniry
- Epigenetics and Development Division, The Walter and Eliza Hall Institute for Medical Research, 1G Royal Parade, Parkville, VIC 3052, Australia
- The Department of Medical Biology, University of Melbourne, Parkville, VIC 3010, Australia
| | - Marnie E Blewitt
- Epigenetics and Development Division, The Walter and Eliza Hall Institute for Medical Research, 1G Royal Parade, Parkville, VIC 3052, Australia
- The Department of Medical Biology, University of Melbourne, Parkville, VIC 3010, Australia
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5
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Tapia Del Fierro A, den Hamer B, Benetti N, Jansz N, Chen K, Beck T, Vanyai H, Gurzau AD, Daxinger L, Xue S, Ly TTN, Wanigasuriya I, Iminitoff M, Breslin K, Oey H, Krom YD, van der Hoorn D, Bouwman LF, Johanson TM, Ritchie ME, Gouil QA, Reversade B, Prin F, Mohun T, van der Maarel SM, McGlinn E, Murphy JM, Keniry A, de Greef JC, Blewitt ME. SMCHD1 has separable roles in chromatin architecture and gene silencing that could be targeted in disease. Nat Commun 2023; 14:5466. [PMID: 37749075 PMCID: PMC10519958 DOI: 10.1038/s41467-023-40992-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Accepted: 08/07/2023] [Indexed: 09/27/2023] Open
Abstract
The interplay between 3D chromatin architecture and gene silencing is incompletely understood. Here, we report a novel point mutation in the non-canonical SMC protein SMCHD1 that enhances its silencing capacity at endogenous developmental targets. Moreover, it also results in enhanced silencing at the facioscapulohumeral muscular dystrophy associated macrosatellite-array, D4Z4, resulting in enhanced repression of DUX4 encoded by this repeat. Heightened SMCHD1 silencing perturbs developmental Hox gene activation, causing a homeotic transformation in mice. Paradoxically, the mutant SMCHD1 appears to enhance insulation against other epigenetic regulators, including PRC2 and CTCF, while depleting long range chromatin interactions akin to what is observed in the absence of SMCHD1. These data suggest that SMCHD1's role in long range chromatin interactions is not directly linked to gene silencing or insulating the chromatin, refining the model for how the different levels of SMCHD1-mediated chromatin regulation interact to bring about gene silencing in normal development and disease.
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Affiliation(s)
- Andres Tapia Del Fierro
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia
- The Department of Medical Biology, University of Melbourne, Melbourne, VIC, Australia
| | - Bianca den Hamer
- Department of Human Genetics, Leiden University Medical Center, Leiden, Netherlands
| | - Natalia Benetti
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia
- The Department of Medical Biology, University of Melbourne, Melbourne, VIC, Australia
| | - Natasha Jansz
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia
- The Department of Medical Biology, University of Melbourne, Melbourne, VIC, Australia
| | - Kelan Chen
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia
- The Department of Medical Biology, University of Melbourne, Melbourne, VIC, Australia
| | - Tamara Beck
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia
| | - Hannah Vanyai
- Crick Advanced Light Microscopy Facility, The Francis Crick Institute, London, UK
| | - Alexandra D Gurzau
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia
- The Department of Medical Biology, University of Melbourne, Melbourne, VIC, Australia
| | - Lucia Daxinger
- Queensland Institute of Medical Research, Brisbane, QLD, Australia
| | - Shifeng Xue
- Department of Biological Sciences, National University of Singapore, Singapore, Singapore
- Institute of Molecular and Cell Biology, A*STAR, Singapore, Singapore
| | - Thanh Thao Nguyen Ly
- Department of Biological Sciences, National University of Singapore, Singapore, Singapore
- Institute of Molecular and Cell Biology, A*STAR, Singapore, Singapore
| | - Iromi Wanigasuriya
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia
- The Department of Medical Biology, University of Melbourne, Melbourne, VIC, Australia
| | - Megan Iminitoff
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia
- The Department of Medical Biology, University of Melbourne, Melbourne, VIC, Australia
| | - Kelsey Breslin
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia
| | - Harald Oey
- Queensland Institute of Medical Research, Brisbane, QLD, Australia
| | - Yvonne D Krom
- Department of Human Genetics, Leiden University Medical Center, Leiden, Netherlands
| | - Dinja van der Hoorn
- Department of Human Genetics, Leiden University Medical Center, Leiden, Netherlands
| | - Linde F Bouwman
- Department of Human Genetics, Leiden University Medical Center, Leiden, Netherlands
| | - Timothy M Johanson
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia
- The Department of Medical Biology, University of Melbourne, Melbourne, VIC, Australia
| | - Matthew E Ritchie
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia
- The Department of Medical Biology, University of Melbourne, Melbourne, VIC, Australia
| | - Quentin A Gouil
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia
- The Department of Medical Biology, University of Melbourne, Melbourne, VIC, Australia
| | - Bruno Reversade
- Institute of Molecular and Cell Biology, A*STAR, Singapore, Singapore
- Genome Institute of Singapore, A*STAR, Singapore, Singapore
| | - Fabrice Prin
- Crick Advanced Light Microscopy Facility, The Francis Crick Institute, London, UK
| | - Timothy Mohun
- Crick Advanced Light Microscopy Facility, The Francis Crick Institute, London, UK
| | | | - Edwina McGlinn
- EMBL Australia, Monash University, Clayton, VIC, Australia
- Australian Regenerative Medicine Institute, Monash University, Clayton, VIC, Australia
| | - James M Murphy
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia
- The Department of Medical Biology, University of Melbourne, Melbourne, VIC, Australia
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, Australia
| | - Andrew Keniry
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia
- The Department of Medical Biology, University of Melbourne, Melbourne, VIC, Australia
| | - Jessica C de Greef
- Department of Human Genetics, Leiden University Medical Center, Leiden, Netherlands
| | - Marnie E Blewitt
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia.
- The Department of Medical Biology, University of Melbourne, Melbourne, VIC, Australia.
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6
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Tian X, Zhou Y, Wang S, Gao M, Xia Y, Li Y, Zhong Y, Xu W, Bai L, Fu B, Zhou Y, Lee HR, Deng H, Lan K, Feng P, Zhang J. Genome-Wide CRISPR-Cas9 Screen Identifies SMCHD1 as a Restriction Factor for Herpesviruses. mBio 2023; 14:e0054923. [PMID: 37010434 PMCID: PMC10128004 DOI: 10.1128/mbio.00549-23] [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: 03/07/2023] [Accepted: 03/10/2023] [Indexed: 04/04/2023] Open
Abstract
Intrinsic immunity is the frontline of host defense against invading pathogens. To combat viral infection, mammalian hosts deploy cell-intrinsic effectors to block viral replication prior to the onset of innate and adaptive immunity. In this study, SMCHD1 is identified as a pivotal cellular factor that restricts Kaposi's sarcoma-associated herpesvirus (KSHV) lytic reactivation through a genome-wide CRISPR-Cas9 knockout screen. Genome-wide chromatin profiling revealed that SMCHD1 associates with the KSHV genome, most prominently the origin of lytic DNA replication (ORI-Lyt). SMCHD1 mutants defective in DNA binding could not bind ORI-Lyt and failed to restrict KSHV lytic replication. Moreover, SMCHD1 functioned as a pan-herpesvirus restriction factor that potently suppressed a wide range of herpesviruses, including alpha, beta, and gamma subfamilies. SMCHD1 deficiency facilitated the replication of a murine herpesvirus in vivo. These findings uncovered SMCHD1 as a restriction factor against herpesviruses, and this could be harnessed for the development of antiviral therapies to limit viral infection. IMPORTANCE Intrinsic immunity represents the frontline of host defense against invading pathogens. However, our understanding of cell-intrinsic antiviral effectors remains limited. In this study, we identified SMCHD1 as a cell-intrinsic restriction factor that controlled KSHV lytic reactivation. Moreover, SMCHD1 restricted the replication of a wide range of herpesviruses by targeting the origins of viral DNA replication (ORIs), and SMCHD1 deficiency facilitated the replication of a murine herpesvirus in vivo. This study helps us to better understand intrinsic antiviral immunity, which may be harnessed to develop new therapeutics for the treatment of herpesvirus infection and the related diseases.
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Affiliation(s)
- Xuezhang Tian
- State Key Laboratory Breeding Base of Basic Science of Stomatology & Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology, State Key Laboratory of Virology, Medical Research Institute, Wuhan University, Wuhan, China
- Frontier Science Center for Immunology and Metabolism, Wuhan University, Wuhan, China
- Department of Pulmonary and Critical Care Medicine, Zhongnan Hospital of Wuhan University, Wuhan, China
- Wuhan Research Center for Infectious Diseases and Cancer, Chinese Academy of Medical Sciences, Wuhan, China
| | - Yaru Zhou
- State Key Laboratory Breeding Base of Basic Science of Stomatology & Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology, State Key Laboratory of Virology, Medical Research Institute, Wuhan University, Wuhan, China
- Frontier Science Center for Immunology and Metabolism, Wuhan University, Wuhan, China
| | - Shaowei Wang
- State Key Laboratory Breeding Base of Basic Science of Stomatology & Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology, State Key Laboratory of Virology, Medical Research Institute, Wuhan University, Wuhan, China
- Frontier Science Center for Immunology and Metabolism, Wuhan University, Wuhan, China
| | - Ming Gao
- State Key Laboratory Breeding Base of Basic Science of Stomatology & Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology, State Key Laboratory of Virology, Medical Research Institute, Wuhan University, Wuhan, China
- Frontier Science Center for Immunology and Metabolism, Wuhan University, Wuhan, China
| | - Yanlin Xia
- State Key Laboratory Breeding Base of Basic Science of Stomatology & Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology, State Key Laboratory of Virology, Medical Research Institute, Wuhan University, Wuhan, China
| | - Yangyang Li
- Frontier Science Center for Immunology and Metabolism, Wuhan University, Wuhan, China
- State Key Laboratory of Virology, School of Life Sciences, Wuhan University, Wuhan, China
| | - Yunhong Zhong
- State Key Laboratory Breeding Base of Basic Science of Stomatology & Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology, State Key Laboratory of Virology, Medical Research Institute, Wuhan University, Wuhan, China
- Frontier Science Center for Immunology and Metabolism, Wuhan University, Wuhan, China
| | - Wenhao Xu
- Frontier Science Center for Immunology and Metabolism, Wuhan University, Wuhan, China
| | - Lei Bai
- Frontier Science Center for Immunology and Metabolism, Wuhan University, Wuhan, China
- State Key Laboratory of Virology, School of Life Sciences, Wuhan University, Wuhan, China
| | - Bishi Fu
- Frontier Science Center for Immunology and Metabolism, Wuhan University, Wuhan, China
| | - Yu Zhou
- Frontier Science Center for Immunology and Metabolism, Wuhan University, Wuhan, China
- State Key Laboratory of Virology, School of Life Sciences, Wuhan University, Wuhan, China
| | - Hye-Ra Lee
- Department of Biotechnology and Bioinformatics, College of Science and Technology, Korea University, Sejong, South Korea
- Department of Lab Medicine, College of Medicine, Korea University, Seoul, South Korea
| | - Hongyu Deng
- CAS Key Laboratory of Infection and Immunity, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Ke Lan
- Frontier Science Center for Immunology and Metabolism, Wuhan University, Wuhan, China
- State Key Laboratory of Virology, School of Life Sciences, Wuhan University, Wuhan, China
| | - Pinghui Feng
- Section of Infection and Immunity, Herman Ostrow School of Dentistry, Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, California, USA
| | - Junjie Zhang
- State Key Laboratory Breeding Base of Basic Science of Stomatology & Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology, State Key Laboratory of Virology, Medical Research Institute, Wuhan University, Wuhan, China
- Frontier Science Center for Immunology and Metabolism, Wuhan University, Wuhan, China
- Department of Pulmonary and Critical Care Medicine, Zhongnan Hospital of Wuhan University, Wuhan, China
- Wuhan Research Center for Infectious Diseases and Cancer, Chinese Academy of Medical Sciences, Wuhan, China
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7
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McCoy AJ, Sammito MD, Read RJ. Implications of AlphaFold2 for crystallographic phasing by molecular replacement. Acta Crystallogr D Struct Biol 2022; 78:1-13. [PMID: 34981757 PMCID: PMC8725160 DOI: 10.1107/s2059798321012122] [Citation(s) in RCA: 48] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Accepted: 11/13/2021] [Indexed: 12/11/2022] Open
Abstract
The AlphaFold2 results in the 14th edition of Critical Assessment of Structure Prediction (CASP14) showed that accurate (low root-mean-square deviation) in silico models of protein structure domains are on the horizon, whether or not the protein is related to known structures through high-coverage sequence similarity. As highly accurate models become available, generated by harnessing the power of correlated mutations and deep learning, one of the aspects of structural biology to be impacted will be methods of phasing in crystallography. Here, the data from CASP14 are used to explore the prospects for changes in phasing methods, and in particular to explore the prospects for molecular-replacement phasing using in silico models.
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Affiliation(s)
- Airlie J. McCoy
- Department of Haematology, Cambridge Institute for Medical Research, University of Cambridge, Hills Road, Cambridge CB2 0XY, United Kingdom
| | - Massimo D. Sammito
- Department of Haematology, Cambridge Institute for Medical Research, University of Cambridge, Hills Road, Cambridge CB2 0XY, United Kingdom
| | - Randy J. Read
- Department of Haematology, Cambridge Institute for Medical Research, University of Cambridge, Hills Road, Cambridge CB2 0XY, United Kingdom
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8
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Takeuchi C, Murano K, Ishikawa M, Okano H, Iwasaki YW. Generation of Stable Drosophila Ovarian Somatic Cell Lines Using the piggyBac System. Methods Mol Biol 2022; 2509:143-153. [PMID: 35796962 DOI: 10.1007/978-1-0716-2380-0_9] [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] [Indexed: 06/15/2023]
Abstract
Transposable elements (TEs) constitute a large proportion of the genome in multiple organisms. Therefore, anti-transposable element machineries are essential to maintain genomic integrity. PIWI-interacting RNAs (piRNAs) are a major force to repress TEs in Drosophila ovaries. Ovarian somatic cells (OSC), in which nuclear piRNA regulation is functional, have been used for research on piRNA pathway as a cell culture system to elucidate the molecular mechanisms underlying the piRNA pathway. Analysis of piRNA pathway using a reporter system to monitor the gene regulation or overexpression of specific genes would be a powerful approach. Here, we present the technical protocol to establish stable cell lines using the piggyBac system, adopted for OSCs. This easy, consistent, and timesaving protocol may accelerate research on the piRNA pathway.
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Affiliation(s)
- Chikara Takeuchi
- Department of Molecular Biology, Keio University School of Medicine, Tokyo, Japan
| | - Kensaku Murano
- Department of Molecular Biology, Keio University School of Medicine, Tokyo, Japan
| | - Mitsuru Ishikawa
- Department of Physiology, Keio University School of Medicine, Tokyo, Japan
| | - Hideyuki Okano
- Department of Physiology, Keio University School of Medicine, Tokyo, Japan
| | - Yuka W Iwasaki
- Department of Molecular Biology, Keio University School of Medicine, Tokyo, Japan.
- Japan Science and Technology Agency (JST), Precursory Research for Embryonic Science and Technology (PRESTO), Saitama, Japan.
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9
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Ozden B, Kryshtafovych A, Karaca E. Assessment of the CASP14 assembly predictions. Proteins 2021; 89:1787-1799. [PMID: 34337786 DOI: 10.1002/prot.26199] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2021] [Revised: 07/08/2021] [Accepted: 07/22/2021] [Indexed: 12/11/2022]
Abstract
In CASP14, 39 research groups submitted more than 2500 3D models on 22 protein complexes. In general, the community performed well in predicting the fold of the assemblies (for 80% of the targets), although it faced significant challenges in reproducing the native contacts. This is especially the case for the complexes without whole-assembly templates. The leading predictor, BAKER-experimental, used a methodology combining classical techniques (template-based modeling, protein docking) with deep learning-based contact predictions and a fold-and-dock approach. The Venclovas team achieved the runner-up position with template-based modeling and docking. By analyzing the target interfaces, we showed that the complexes with depleted charged contacts or dominating hydrophobic interactions were the most challenging ones to predict. We also demonstrated that if AlphaFold2 predictions were at hand, the interface prediction challenge could be alleviated for most of the targets. All in all, it is evident that new approaches are needed for the accurate prediction of assemblies, which undoubtedly will expand on the significant improvements in the tertiary structure prediction field.
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Affiliation(s)
- Burcu Ozden
- Izmir Biomedicine and Genome Center, Izmir, Turkey.,Izmir International Biomedicine and Genome Institute, Dokuz Eylul University, Izmir, Turkey
| | - Andriy Kryshtafovych
- Protein Structure Prediction Center, Genome and Biomedical Sciences Facilities, University of California, Davis, California, USA
| | - Ezgi Karaca
- Izmir Biomedicine and Genome Center, Izmir, Turkey.,Izmir International Biomedicine and Genome Institute, Dokuz Eylul University, Izmir, Turkey
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10
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SMCHD1's ubiquitin-like domain is required for N-terminal dimerization and chromatin localization. Biochem J 2021; 478:2555-2569. [PMID: 34109974 PMCID: PMC8286825 DOI: 10.1042/bcj20210278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Revised: 05/28/2021] [Accepted: 06/10/2021] [Indexed: 11/17/2022]
Abstract
Structural maintenance of chromosomes flexible hinge domain-containing 1 (SMCHD1) is an epigenetic regulator that mediates gene expression silencing at targeted sites across the genome. Our current understanding of SMCHD1's molecular mechanism, and how substitutions within SMCHD1 lead to the diseases, facioscapulohumeral muscular dystrophy (FSHD) and Bosma arhinia microphthalmia syndrome (BAMS), are only emerging. Recent structural studies of its two component domains - the N-terminal ATPase and C-terminal SMC hinge - suggest that dimerization of each domain plays a central role in SMCHD1 function. Here, using biophysical techniques, we demonstrate that the SMCHD1 ATPase undergoes dimerization in a process that is dependent on both the N-terminal UBL (Ubiquitin-like) domain and ATP binding. We show that neither the dimerization event, nor the presence of a C-terminal extension past the transducer domain, affect SMCHD1's in vitro catalytic activity as the rate of ATP turnover remains comparable to the monomeric protein. We further examined the functional importance of the N-terminal UBL domain in cells, revealing that its targeted deletion disrupts the localization of full-length SMCHD1 to chromatin. These findings implicate UBL-mediated SMCHD1 dimerization as a crucial step for chromatin interaction, and thereby for promoting SMCHD1-mediated gene silencing.
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11
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Relating SMCHD1 structure to its function in epigenetic silencing. Biochem Soc Trans 2021; 48:1751-1763. [PMID: 32779700 PMCID: PMC7458401 DOI: 10.1042/bst20200242] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 07/12/2020] [Accepted: 07/13/2020] [Indexed: 02/07/2023]
Abstract
The structural maintenance of chromosomes hinge domain containing protein 1 (SMCHD1) is a large multidomain protein involved in epigenetic gene silencing. Variations in the SMCHD1 gene are associated with two debilitating human disorders, facioscapulohumeral muscular dystrophy (FSHD) and Bosma arhinia microphthalmia syndrome (BAMS). Failure of SMCHD1 to silence the D4Z4 macro-repeat array causes FSHD, yet the consequences on gene silencing of SMCHD1 variations associated with BAMS are currently unknown. Despite the interest due to these roles, our understanding of the SMCHD1 protein is in its infancy. Most knowledge of SMCHD1 function is based on its similarity to the structural maintenance of chromosomes (SMC) proteins, such as cohesin and condensin. SMC proteins and SMCHD1 share similar domain organisation and affect chromatin conformation. However, there are important differences between the domain architectures of SMC proteins and SMCHD1, which distinguish SMCHD1 as a non-canonical member of the family. In the last year, the crystal structures of the two key domains crucial to SMCHD1 function, the ATPase and hinge domains, have emerged. These structures reveal new insights into how SMCHD1 may bind and regulate chromatin structure, and address how amino acid variations in SMCHD1 may contribute to BAMS and FSHD. Here, we contrast SMCHD1 with canonical SMC proteins, and relate the ATPase and hinge domain structures to their roles in SMCHD1-mediated epigenetic silencing and disease.
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12
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Oliver MR, Horne CR, Shrestha S, Keown JR, Liang LY, Young SN, Sandow JJ, Webb AI, Goldstone DC, Lucet IS, Kannan N, Metcalf P, Murphy JM. Granulovirus PK-1 kinase activity relies on a side-to-side dimerization mode centered on the regulatory αC helix. Nat Commun 2021; 12:1002. [PMID: 33579933 PMCID: PMC7881018 DOI: 10.1038/s41467-021-21191-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Accepted: 01/19/2021] [Indexed: 12/19/2022] Open
Abstract
The life cycle of Baculoviridae family insect viruses depends on the viral protein kinase, PK-1, to phosphorylate the regulatory protein, p6.9, to induce baculoviral genome release. Here, we report the crystal structure of Cydia pomenella granulovirus PK-1, which, owing to its likely ancestral origin among host cell AGC kinases, exhibits a eukaryotic protein kinase fold. PK-1 occurs as a rigid dimer, where an antiparallel arrangement of the αC helices at the dimer core stabilizes PK-1 in a closed, active conformation. Dimerization is facilitated by C-lobe:C-lobe and N-lobe:N-lobe interactions between protomers, including the domain-swapping of an N-terminal helix that crowns a contiguous β-sheet formed by the two N-lobes. PK-1 retains a dimeric conformation in solution, which is crucial for catalytic activity. Our studies raise the prospect that parallel, side-to-side dimeric arrangements that lock kinase domains in a catalytically-active conformation could function more broadly as a regulatory mechanism among eukaryotic protein kinases. The viral Protein Kinase-1 (PK-1) phosphorylates the regulatory protein p6.9, which facilitates baculoviral genome release. Here, the authors combine X-ray crystallography with biophysical and biochemical analyses as well as molecular dynamics simulations to characterize Cydia pomenella granulovirus PK-1, which forms a dimer with a parallel side-to-side arrangement of the kinase domains and furthermore, they provide insights into its catalytic mechanism and evolutionary relationships with other kinases.
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Affiliation(s)
- Michael R Oliver
- School of Biological Sciences, University of Auckland, Auckland, New Zealand.,School of Biological Sciences, University of Edinburgh, Edinburgh, UK
| | - Christopher R Horne
- Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia.,Department of Medical Biology, University of Melbourne, Parkville, VIC, Australia
| | - Safal Shrestha
- Institute of Bioinformatics, University of Georgia, Athens, GA, USA
| | - Jeremy R Keown
- School of Biological Sciences, University of Auckland, Auckland, New Zealand.,Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK
| | - Lung-Yu Liang
- Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia.,Department of Medical Biology, University of Melbourne, Parkville, VIC, Australia
| | - Samuel N Young
- Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia
| | - Jarrod J Sandow
- Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia.,Department of Medical Biology, University of Melbourne, Parkville, VIC, Australia
| | - Andrew I Webb
- Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia.,Department of Medical Biology, University of Melbourne, Parkville, VIC, Australia
| | - David C Goldstone
- School of Biological Sciences, University of Auckland, Auckland, New Zealand
| | - Isabelle S Lucet
- Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia.,Department of Medical Biology, University of Melbourne, Parkville, VIC, Australia
| | - Natarajan Kannan
- Institute of Bioinformatics, University of Georgia, Athens, GA, USA.,Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, USA
| | - Peter Metcalf
- School of Biological Sciences, University of Auckland, Auckland, New Zealand.
| | - James M Murphy
- Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia. .,Department of Medical Biology, University of Melbourne, Parkville, VIC, Australia.
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13
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Huang Z, Yu J, Cui W, Johnson BK, Kim K, Pfeifer GP. The chromosomal protein SMCHD1 regulates DNA methylation and the 2c-like state of embryonic stem cells by antagonizing TET proteins. SCIENCE ADVANCES 2021; 7:7/4/eabb9149. [PMID: 33523915 PMCID: PMC7817097 DOI: 10.1126/sciadv.abb9149] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Accepted: 11/24/2020] [Indexed: 05/15/2023]
Abstract
5-Methylcytosine (5mC) oxidases, the ten-eleven translocation (TET) proteins, initiate DNA demethylation, but it is unclear how 5mC oxidation is regulated. We show that the protein SMCHD1 (structural maintenance of chromosomes flexible hinge domain containing 1) is found in complexes with TET proteins and negatively regulates TET activities. Removal of SMCHD1 from mouse embryonic stem (ES) cells induces DNA hypomethylation, preferentially at SMCHD1 target sites and accumulation of 5-hydroxymethylcytosine (5hmC), along with promoter demethylation and activation of the Dux double-homeobox gene. In the absence of SMCHD1, ES cells acquire a two-cell (2c) embryo-like state characterized by activation of an early embryonic transcriptome that is substantially imposed by Dux Using Smchd1/Tet1/Tet2/Tet3 quadruple-knockout cells, we show that DNA demethylation, activation of Dux, and other genes upon SMCHD1 loss depend on TET proteins. These data identify SMCHD1 as an antagonist of the 2c-like state of ES cells and of TET-mediated DNA demethylation.
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Affiliation(s)
- Zhijun Huang
- Center for Epigenetics, Van Andel Institute, Grand Rapids, MI 49503, USA
| | - Jiyoung Yu
- Center for Epigenetics, Van Andel Institute, Grand Rapids, MI 49503, USA
- Asan Medical Center, University of Ulsan, College of Medicine, Songpa, Seoul, South Korea
| | - Wei Cui
- Center for Epigenetics, Van Andel Institute, Grand Rapids, MI 49503, USA
| | - Benjamin K Johnson
- Center for Epigenetics, Van Andel Institute, Grand Rapids, MI 49503, USA
| | - Kyunggon Kim
- Asan Medical Center, University of Ulsan, College of Medicine, Songpa, Seoul, South Korea
| | - Gerd P Pfeifer
- Center for Epigenetics, Van Andel Institute, Grand Rapids, MI 49503, USA.
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