1
|
Li Q, Zhang J, Haluska C, Zhang X, Wang L, Liu G, Wang Z, Jin D, Cheng T, Wang H, Tian Y, Wang X, Sun L, Zhao X, Chen Z, Wang L. Cryo-EM structures of Smc5/6 in multiple states reveal its assembly and functional mechanisms. Nat Struct Mol Biol 2024:10.1038/s41594-024-01319-1. [PMID: 38890552 DOI: 10.1038/s41594-024-01319-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2023] [Accepted: 04/17/2024] [Indexed: 06/20/2024]
Abstract
Smc5/6 is a member of the eukaryotic structural maintenance of chromosomes (SMC) family of complexes with important roles in genome maintenance and viral restriction. However, limited structural understanding of Smc5/6 hinders the elucidation of its diverse functions. Here, we report cryo-EM structures of the budding yeast Smc5/6 complex in eight-subunit, six-subunit and five-subunit states. Structural maps throughout the entire length of these complexes reveal modularity and key elements in complex assembly. We show that the non-SMC element (Nse)2 subunit supports the overall shape of the complex and uses a wedge motif to aid the stability and function of the complex. The Nse6 subunit features a flexible hook region for attachment to the Smc5 and Smc6 arm regions, contributing to the DNA repair roles of the complex. Our results also suggest a structural basis for the opposite effects of the Nse1-3-4 and Nse5-6 subcomplexes in regulating Smc5/6 ATPase activity. Collectively, our integrated structural and functional data provide a framework for understanding Smc5/6 assembly and function.
Collapse
Affiliation(s)
- Qian Li
- The Center for Microbes, Development and Health, CAS Key Laboratory of Molecular Virology and Immunology, Shanghai Institute of Immunity and Infection, Chinese Academy of Sciences,University of Chinese Academy of Sciences, Shanghai, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Jun Zhang
- The Center for Microbes, Development and Health, CAS Key Laboratory of Molecular Virology and Immunology, Shanghai Institute of Immunity and Infection, Chinese Academy of Sciences,University of Chinese Academy of Sciences, Shanghai, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Cory Haluska
- Molecular Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Xiang Zhang
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS) and Shanghai Institute of Infectious Disease and Biosecurity, Shanghai Fifth People's Hospital, Shanghai Public Health Clinical Center, Institutes of Biomedical Sciences, School of Basic Medical Sciences,Fudan University, Shanghai, China
| | - Lei Wang
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
- CAS Key Laboratory of Infection and Immunity, National Laboratory of Macromolecules, Institute of Biophysics,Chinese Academy of Sciences, Beijing, China
| | - Guangfeng Liu
- National Center for Protein Science Shanghai, Shanghai Advanced Research Institute,Chinese Academy of Sciences, Shanghai, China
| | - Zhaoning Wang
- The Center for Microbes, Development and Health, CAS Key Laboratory of Molecular Virology and Immunology, Shanghai Institute of Immunity and Infection, Chinese Academy of Sciences,University of Chinese Academy of Sciences, Shanghai, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Duo Jin
- The Center for Microbes, Development and Health, CAS Key Laboratory of Molecular Virology and Immunology, Shanghai Institute of Immunity and Infection, Chinese Academy of Sciences,University of Chinese Academy of Sciences, Shanghai, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Tong Cheng
- The Center for Microbes, Development and Health, CAS Key Laboratory of Molecular Virology and Immunology, Shanghai Institute of Immunity and Infection, Chinese Academy of Sciences,University of Chinese Academy of Sciences, Shanghai, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Hongxia Wang
- The Center for Microbes, Development and Health, CAS Key Laboratory of Molecular Virology and Immunology, Shanghai Institute of Immunity and Infection, Chinese Academy of Sciences,University of Chinese Academy of Sciences, Shanghai, China
| | - Yuan Tian
- The Center for Microbes, Development and Health, CAS Key Laboratory of Molecular Virology and Immunology, Shanghai Institute of Immunity and Infection, Chinese Academy of Sciences,University of Chinese Academy of Sciences, Shanghai, China
| | - Xiangxi Wang
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
- CAS Key Laboratory of Infection and Immunity, National Laboratory of Macromolecules, Institute of Biophysics,Chinese Academy of Sciences, Beijing, China
| | - Lei Sun
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS) and Shanghai Institute of Infectious Disease and Biosecurity, Shanghai Fifth People's Hospital, Shanghai Public Health Clinical Center, Institutes of Biomedical Sciences, School of Basic Medical Sciences,Fudan University, Shanghai, China
| | - Xiaolan Zhao
- Molecular Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY, USA.
| | - Zhenguo Chen
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS) and Shanghai Institute of Infectious Disease and Biosecurity, Shanghai Fifth People's Hospital, Shanghai Public Health Clinical Center, Institutes of Biomedical Sciences, School of Basic Medical Sciences,Fudan University, Shanghai, China.
| | - Lanfeng Wang
- The Center for Microbes, Development and Health, CAS Key Laboratory of Molecular Virology and Immunology, Shanghai Institute of Immunity and Infection, Chinese Academy of Sciences,University of Chinese Academy of Sciences, Shanghai, China.
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China.
| |
Collapse
|
2
|
Cho T, Hoeg L, Setiaputra D, Durocher D. NFATC2IP is a mediator of SUMO-dependent genome integrity. Genes Dev 2024; 38:233-252. [PMID: 38503515 PMCID: PMC11065178 DOI: 10.1101/gad.350914.123] [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: 07/05/2023] [Accepted: 03/04/2024] [Indexed: 03/21/2024]
Abstract
The post-translational modification of proteins by SUMO is crucial for cellular viability and mammalian development in part due to the contribution of SUMOylation to genome duplication and repair. To investigate the mechanisms underpinning the essential function of SUMO, we undertook a genome-scale CRISPR/Cas9 screen probing the response to SUMOylation inhibition. This effort identified 130 genes whose disruption reduces or enhances the toxicity of TAK-981, a clinical-stage inhibitor of the SUMO E1-activating enzyme. Among the strongest hits, we validated and characterized NFATC2IP, an evolutionarily conserved protein related to the fungal Esc2 and Rad60 proteins that harbors tandem SUMO-like domains. Cells lacking NFATC2IP are viable but are hypersensitive to SUMO E1 inhibition, likely due to the accumulation of mitotic chromosome bridges and micronuclei. NFATC2IP primarily acts in interphase and associates with nascent DNA, suggesting a role in the postreplicative resolution of replication or recombination intermediates. Mechanistically, NFATC2IP interacts with the SMC5/6 complex and UBC9, the SUMO E2, via its first and second SUMO-like domains, respectively. AlphaFold-Multimer modeling suggests that NFATC2IP positions and activates the UBC9-NSMCE2 complex, the SUMO E3 ligase associated with SMC5/SMC6. We conclude that NFATC2IP is a key mediator of SUMO-dependent genomic integrity that collaborates with the SMC5/6 complex.
Collapse
Affiliation(s)
- Tiffany Cho
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario M5G 1X5, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario M5S 1A8, Canada
| | - Lisa Hoeg
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario M5G 1X5, Canada
| | - Dheva Setiaputra
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario M5G 1X5, Canada
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada
| | - Daniel Durocher
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario M5G 1X5, Canada;
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario M5S 1A8, Canada
| |
Collapse
|
3
|
Roy S, Adhikary H, D’Amours D. The SMC5/6 complex: folding chromosomes back into shape when genomes take a break. Nucleic Acids Res 2024; 52:2112-2129. [PMID: 38375830 PMCID: PMC10954462 DOI: 10.1093/nar/gkae103] [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: 11/13/2023] [Revised: 01/28/2024] [Accepted: 02/01/2024] [Indexed: 02/21/2024] Open
Abstract
High-level folding of chromatin is a key determinant of the shape and functional state of chromosomes. During cell division, structural maintenance of chromosome (SMC) complexes such as condensin and cohesin ensure large-scale folding of chromatin into visible chromosomes. In contrast, the SMC5/6 complex plays more local and context-specific roles in the structural organization of interphase chromosomes with important implications for health and disease. Recent advances in single-molecule biophysics and cryo-electron microscopy revealed key insights into the architecture of the SMC5/6 complex and how interactions connecting the complex to chromatin components give rise to its unique repertoire of interphase functions. In this review, we provide an integrative view of the features that differentiates the SMC5/6 complex from other SMC enzymes and how these enable dramatic reorganization of DNA folding in space during DNA repair reactions and other genome transactions. Finally, we explore the mechanistic basis for the dynamic targeting of the SMC5/6 complex to damaged chromatin and its crucial role in human health.
Collapse
Affiliation(s)
- Shamayita Roy
- Ottawa Institute of Systems Biology, Department of Cellular and Molecular Medicine, University of Ottawa, Roger Guindon Hall, 451 Smyth Rd, Ottawa, ON K1H 8M5, Canada
| | - Hemanta Adhikary
- Ottawa Institute of Systems Biology, Department of Cellular and Molecular Medicine, University of Ottawa, Roger Guindon Hall, 451 Smyth Rd, Ottawa, ON K1H 8M5, Canada
| | - Damien D’Amours
- Ottawa Institute of Systems Biology, Department of Cellular and Molecular Medicine, University of Ottawa, Roger Guindon Hall, 451 Smyth Rd, Ottawa, ON K1H 8M5, Canada
| |
Collapse
|
4
|
Little J, Chikina M, Clark NL. Evolutionary rate covariation is a reliable predictor of co-functional interactions but not necessarily physical interactions. eLife 2024; 12:RP93333. [PMID: 38415754 PMCID: PMC10942632 DOI: 10.7554/elife.93333] [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: 02/29/2024] Open
Abstract
Co-functional proteins tend to have rates of evolution that covary over time. This correlation between evolutionary rates can be measured over the branches of a phylogenetic tree through methods such as evolutionary rate covariation (ERC), and then used to construct gene networks by the identification of proteins with functional interactions. The cause of this correlation has been hypothesized to result from both compensatory coevolution at physical interfaces and nonphysical forces such as shared changes in selective pressure. This study explores whether coevolution due to compensatory mutations has a measurable effect on the ERC signal. We examined the difference in ERC signal between physically interacting protein domains within complexes compared to domains of the same proteins that do not physically interact. We found no generalizable relationship between physical interaction and high ERC, although a few complexes ranked physical interactions higher than nonphysical interactions. Therefore, we conclude that coevolution due to physical interaction is weak, but present in the signal captured by ERC, and we hypothesize that the stronger signal instead comes from selective pressures on the protein as a whole and maintenance of the general function.
Collapse
Affiliation(s)
- Jordan Little
- Department of Human Genetics, University of UtahSalt Lake CityUnited States
| | - Maria Chikina
- Department of Computational Biology, University of PittsburghPittsburghUnited States
| | - Nathan L Clark
- Department of Human Genetics, University of UtahSalt Lake CityUnited States
- Department of Biological Sciences, University of PittsburghPittsburghUnited States
| |
Collapse
|
5
|
Xu MJ, Jordan PW. SMC5/6 Promotes Replication Fork Stability via Negative Regulation of the COP9 Signalosome. Int J Mol Sci 2024; 25:952. [PMID: 38256025 PMCID: PMC10815603 DOI: 10.3390/ijms25020952] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2023] [Revised: 01/06/2024] [Accepted: 01/10/2024] [Indexed: 01/24/2024] Open
Abstract
It is widely accepted that DNA replication fork stalling is a common occurrence during cell proliferation, but there are robust mechanisms to alleviate this and ensure DNA replication is completed prior to chromosome segregation. The SMC5/6 complex has consistently been implicated in the maintenance of replication fork integrity. However, the essential role of the SMC5/6 complex during DNA replication in mammalian cells has not been elucidated. In this study, we investigate the molecular consequences of SMC5/6 loss at the replication fork in mouse embryonic stem cells (mESCs), employing the auxin-inducible degron (AID) system to deplete SMC5 acutely and reversibly in the defined cellular contexts of replication fork stall and restart. In SMC5-depleted cells, we identify a defect in the restart of stalled replication forks, underpinned by excess MRE11-mediated fork resection and a perturbed localization of fork protection factors to the stalled fork. Previously, we demonstrated a physical and functional interaction of SMC5/6 with the COP9 signalosome (CSN), a cullin deneddylase that enzymatically regulates cullin ring ligase (CRL) activity. Employing a combination of DNA fiber techniques, the AID system, small-molecule inhibition assays, and immunofluorescence microscopy analyses, we show that SMC5/6 promotes the localization of fork protection factors to stalled replication forks by negatively modulating the COP9 signalosome (CSN). We propose that the SMC5/6-mediated modulation of the CSN ensures that CRL activity and their roles in DNA replication fork stabilization are maintained to allow for efficient replication fork restart when a replication fork stall is alleviated.
Collapse
Affiliation(s)
- Michelle J. Xu
- Department of Biochemistry and Molecular Biology, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD 21205, USA
| | - Philip W. Jordan
- Department of Biochemistry and Molecular Biology, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD 21205, USA
- Department of Biochemistry and Molecular Biology, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA
| |
Collapse
|
6
|
O’Brien MP, Pryzhkova MV, Lake EMR, Mandino F, Shen X, Karnik R, Atkins A, Xu MJ, Ji W, Konstantino M, Brueckner M, Ment LR, Khokha MK, Jordan PW. SMC5 Plays Independent Roles in Congenital Heart Disease and Neurodevelopmental Disability. Int J Mol Sci 2023; 25:430. [PMID: 38203602 PMCID: PMC10779392 DOI: 10.3390/ijms25010430] [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: 11/30/2023] [Revised: 12/19/2023] [Accepted: 12/20/2023] [Indexed: 01/12/2024] Open
Abstract
Up to 50% of patients with severe congenital heart disease (CHD) develop life-altering neurodevelopmental disability (NDD). It has been presumed that NDD arises in CHD cases because of hypoxia before, during, or after cardiac surgery. Recent studies detected an enrichment in de novo mutations in CHD and NDD, as well as significant overlap between CHD and NDD candidate genes. However, there is limited evidence demonstrating that genes causing CHD can produce NDD independent of hypoxia. A patient with hypoplastic left heart syndrome and gross motor delay presented with a de novo mutation in SMC5. Modeling mutation of smc5 in Xenopus tropicalis embryos resulted in reduced heart size, decreased brain length, and disrupted pax6 patterning. To evaluate the cardiac development, we induced the conditional knockout (cKO) of Smc5 in mouse cardiomyocytes, which led to the depletion of mature cardiomyocytes and abnormal contractility. To test a role for Smc5 specifically in the brain, we induced cKO in the mouse central nervous system, which resulted in decreased brain volume, and diminished connectivity between areas related to motor function but did not affect vascular or brain ventricular volume. We propose that genetic factors, rather than hypoxia alone, can contribute when NDD and CHD cases occur concurrently.
Collapse
Affiliation(s)
- Matthew P. O’Brien
- Department of Pediatrics, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06510, USA
| | - Marina V. Pryzhkova
- Biochemistry and Molecular Biology Department, Johns Hopkins University Bloomberg School of Public Health, 615 N Wolfe St, Baltimore, MD 21205, USA
- Department of Biochemistry and Molecular Biology, Uniformed Services, University of the Health Sciences, 4301 Jones Bridge Rd, Bethesda, MD 20814, USA
| | - Evelyn M. R. Lake
- Department of Radiology and Biomedical Imaging, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06510, USA
| | - Francesca Mandino
- Department of Radiology and Biomedical Imaging, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06510, USA
| | - Xilin Shen
- Department of Radiology and Biomedical Imaging, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06510, USA
| | - Ruchika Karnik
- Department of Pediatrics, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06510, USA
| | - Alisa Atkins
- Biochemistry and Molecular Biology Department, Johns Hopkins University Bloomberg School of Public Health, 615 N Wolfe St, Baltimore, MD 21205, USA
| | - Michelle J. Xu
- Biochemistry and Molecular Biology Department, Johns Hopkins University Bloomberg School of Public Health, 615 N Wolfe St, Baltimore, MD 21205, USA
| | - Weizhen Ji
- Department of Pediatrics, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06510, USA
- Pediatric Genomics Discovery Program, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06510, USA
| | - Monica Konstantino
- Department of Pediatrics, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06510, USA
- Pediatric Genomics Discovery Program, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06510, USA
| | - Martina Brueckner
- Department of Pediatrics, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06510, USA
- Department of Genetics, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06510, USA
| | - Laura R. Ment
- Department of Pediatrics, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06510, USA
- Department of Neurology, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06510, USA
| | - Mustafa K. Khokha
- Department of Pediatrics, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06510, USA
- Pediatric Genomics Discovery Program, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06510, USA
- Department of Genetics, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06510, USA
| | - Philip W. Jordan
- Biochemistry and Molecular Biology Department, Johns Hopkins University Bloomberg School of Public Health, 615 N Wolfe St, Baltimore, MD 21205, USA
- Department of Biochemistry and Molecular Biology, Uniformed Services, University of the Health Sciences, 4301 Jones Bridge Rd, Bethesda, MD 20814, USA
| |
Collapse
|
7
|
Li S, Yu Y, Zheng J, Miller-Browne V, Ser Z, Kuang H, Patel DJ, Zhao X. Molecular basis for Nse5-6 mediated regulation of Smc5/6 functions. Proc Natl Acad Sci U S A 2023; 120:e2310924120. [PMID: 37903273 PMCID: PMC10636319 DOI: 10.1073/pnas.2310924120] [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: 07/08/2023] [Accepted: 09/29/2023] [Indexed: 11/01/2023] Open
Abstract
The Smc5/6 complex (Smc5/6) is important for genome replication and repair in eukaryotes. Its cellular functions are closely linked to the ATPase activity of the Smc5 and Smc6 subunits. This activity requires the dimerization of the motor domains of the two SMC subunits and is regulated by the six non-SMC subunits (Nse1 to Nse6). Among the NSEs, Nse5 and Nse6 form a stable subcomplex (Nse5-6) that dampens the ATPase activity of the complex. However, the underlying mechanisms and biological significance of this regulation remain unclear. Here, we address these issues using structural and functional studies. We determined cryo-EM structures of the yeast Smc5/6 derived from complexes consisting of either all eight subunits or a subset of five subunits. Both structures reveal that Nse5-6 associates with Smc6's motor domain and the adjacent coiled-coil segment, termed the neck region. Our structural analyses reveal that this binding is compatible with motor domain dimerization but results in dislodging the Nse4 subunit from the Smc6 neck. As the Nse4-Smc6 neck interaction favors motor domain engagement and thus ATPase activity, Nse6's competition with Nse4 can explain how Nse5-6 disfavors ATPase activity. Such regulation could in principle differentially affect Smc5/6-mediated processes depending on their needs of the complex's ATPase activity. Indeed, mutagenesis data in cells provide evidence that the Nse6-Smc6 neck interaction is important for the resolution of DNA repair intermediates but not for replication termination. Our results thus provide a molecular basis for how Nse5-6 modulates the ATPase activity and cellular functions of Smc5/6.
Collapse
Affiliation(s)
- Shibai Li
- Molecular Biology Program, Memorial Sloan-Kettering Cancer Center, New York, NY10065
| | - You Yu
- Structural Biology Program, Memorial Sloan-Kettering Cancer Center, New York, NY10065
| | - Jian Zheng
- Molecular Biology Program, Memorial Sloan-Kettering Cancer Center, New York, NY10065
- Programs in Biochemistry, Cell, and Molecular Biology, Weill Cornell Graduate School of Medical Sciences, New York, NY10065
| | - Victoria Miller-Browne
- Molecular Biology Program, Memorial Sloan-Kettering Cancer Center, New York, NY10065
- Programs in Biochemistry, Cell, and Molecular Biology, Weill Cornell Graduate School of Medical Sciences, New York, NY10065
| | - Zheng Ser
- Functional Proteomics Laboratory, Institute of Molecular and Cell Biology, Agency for Science, Technology and Research, Proteos, Singapore138673, Singapore
| | - Huihui Kuang
- Simons Electron Microscopy Center, New York Structural Biology Center, New York, NY10027
| | - Dinshaw J. Patel
- Structural Biology Program, Memorial Sloan-Kettering Cancer Center, New York, NY10065
| | - Xiaolan Zhao
- Molecular Biology Program, Memorial Sloan-Kettering Cancer Center, New York, NY10065
| |
Collapse
|
8
|
Roy S, Zaker A, Mer A, D’Amours D. Large-scale phenogenomic analysis of human cancers uncovers frequent alterations affecting SMC5/6 complex components in breast cancer. NAR Cancer 2023; 5:zcad047. [PMID: 37705607 PMCID: PMC10495288 DOI: 10.1093/narcan/zcad047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Revised: 08/09/2023] [Accepted: 08/22/2023] [Indexed: 09/15/2023] Open
Abstract
Cancer cells often experience large-scale alterations in genome architecture because of DNA damage and replication stress. Whether mutations in core regulators of chromosome structure can also lead to cancer-promoting loss in genome stability is not fully understood. To address this question, we conducted a systematic analysis of mutations affecting a global regulator of chromosome biology -the SMC5/6 complex- in cancer genomics cohorts. Analysis of 64 959 cancer samples spanning 144 tissue types and 199 different cancer genome studies revealed that the SMC5/6 complex is frequently altered in breast cancer patients. Patient-derived mutations targeting this complex associate with strong phenotypic outcomes such as loss of ploidy control and reduced overall survival. Remarkably, the phenotypic impact of several patient mutations can be observed in a heterozygous context, hence providing an explanation for a prominent role of SMC5/6 mutations in breast cancer pathogenesis. Overall, our findings suggest that genes encoding global effectors of chromosome architecture can act as key contributors to cancer development in humans.
Collapse
Affiliation(s)
- Shamayita Roy
- Ottawa Institute of Systems Biology, Department of Cellular and Molecular Medicine, University of Ottawa, Roger Guindon Hall, 451 Smyth Rd, Ottawa, ON K1H 8M5, Canada
| | - Arvin Zaker
- Department of Biochemistry, Microbiology & Immunology, University of Ottawa, Roger Guindon Hall, 451 Smyth Rd, Ottawa, ON K1H 8M5, Canada
| | - Arvind Mer
- Department of Biochemistry, Microbiology & Immunology, University of Ottawa, Roger Guindon Hall, 451 Smyth Rd, Ottawa, ON K1H 8M5, Canada
| | - Damien D’Amours
- Ottawa Institute of Systems Biology, Department of Cellular and Molecular Medicine, University of Ottawa, Roger Guindon Hall, 451 Smyth Rd, Ottawa, ON K1H 8M5, Canada
| |
Collapse
|
9
|
Bürmann F, Löwe J. Structural biology of SMC complexes across the tree of life. Curr Opin Struct Biol 2023; 80:102598. [PMID: 37104976 PMCID: PMC10512200 DOI: 10.1016/j.sbi.2023.102598] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 03/20/2023] [Accepted: 03/26/2023] [Indexed: 04/29/2023]
Abstract
Structural maintenance of chromosomes (SMC) complexes guard and organize the three-dimensional structure of chromosomal DNA across the tree of life. Many SMC functions can be explained by an inherent motor activity that extrudes large DNA loops while the complexes move along their substrate. Here, we review recent structural insights into the architecture and conservation of these molecular machines, their interaction with DNA, and the conformational changes that are linked to their ATP hydrolysis cycle.
Collapse
Affiliation(s)
- Frank Bürmann
- MRC Laboratory of Molecular Biology, Structural Studies Division, Cambridge Biomedical Campus, Cambridge, CB2 0QH, UK
| | - Jan Löwe
- MRC Laboratory of Molecular Biology, Structural Studies Division, Cambridge Biomedical Campus, Cambridge, CB2 0QH, UK.
| |
Collapse
|
10
|
Peng XP, Zhao X. The multi-functional Smc5/6 complex in genome protection and disease. Nat Struct Mol Biol 2023; 30:724-734. [PMID: 37336994 PMCID: PMC10372777 DOI: 10.1038/s41594-023-01015-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Accepted: 05/05/2023] [Indexed: 06/21/2023]
Abstract
Structural maintenance of chromosomes (SMC) complexes are ubiquitous genome regulators with a wide range of functions. Among the three types of SMC complexes in eukaryotes, cohesin and condensin fold the genome into different domains and structures, while Smc5/6 plays direct roles in promoting chromosomal replication and repair and in restraining pathogenic viral extra-chromosomal DNA. The importance of Smc5/6 for growth, genotoxin resistance and host defense across species is highlighted by its involvement in disease prevention in plants and animals. Accelerated progress in recent years, including structural and single-molecule studies, has begun to provide greater insights into the mechanisms underlying Smc5/6 functions. Here we integrate a broad range of recent studies on Smc5/6 to identify emerging features of this unique SMC complex and to explain its diverse cellular functions and roles in disease pathogenesis. We also highlight many key areas requiring further investigation for achieving coherent views of Smc5/6-driven mechanisms.
Collapse
Affiliation(s)
- Xiao P Peng
- Department of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Xiaolan Zhao
- Molecular Biology Program, Sloan Kettering Cancer Institute, Memorial Sloan Kettering Cancer Center, New York, NY, USA.
| |
Collapse
|
11
|
Taschner M, Gruber S. DNA segment capture by Smc5/6 holocomplexes. Nat Struct Mol Biol 2023; 30:619-628. [PMID: 37012407 DOI: 10.1038/s41594-023-00956-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2022] [Accepted: 03/01/2023] [Indexed: 04/05/2023]
Abstract
Three distinct structural maintenance of chromosomes (SMC) complexes facilitate chromosome folding and segregation in eukaryotes, presumably by DNA loop extrusion. How SMCs interact with DNA to extrude loops is not well understood. Among the SMC complexes, Smc5/6 has dedicated roles in DNA repair and preventing a buildup of aberrant DNA junctions. In the present study, we describe the reconstitution of ATP-dependent DNA loading by yeast Smc5/6 rings. Loading strictly requires the Nse5/6 subcomplex which opens the kleisin neck gate. We show that plasmid molecules are topologically entrapped in the kleisin and two SMC subcompartments, but not in the full SMC compartment. This is explained by the SMC compartment holding a looped DNA segment and by kleisin locking it in place when passing between the two flanks of the loop for neck-gate closure. Related segment capture events may provide the power stroke in subsequent DNA extrusion steps, possibly also in other SMC complexes, thus providing a unifying principle for DNA loading and extrusion.
Collapse
Affiliation(s)
- Michael Taschner
- Department of Fundamental Microbiology, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | - Stephan Gruber
- Department of Fundamental Microbiology, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland.
| |
Collapse
|
12
|
Pradhan B, Kanno T, Umeda Igarashi M, Loke MS, Baaske MD, Wong JSK, Jeppsson K, Björkegren C, Kim E. The Smc5/6 complex is a DNA loop-extruding motor. Nature 2023; 616:843-848. [PMID: 37076626 PMCID: PMC10132971 DOI: 10.1038/s41586-023-05963-3] [Citation(s) in RCA: 33] [Impact Index Per Article: 33.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Accepted: 03/16/2023] [Indexed: 04/21/2023]
Abstract
Structural maintenance of chromosomes (SMC) protein complexes are essential for the spatial organization of chromosomes1. Whereas cohesin and condensin organize chromosomes by extrusion of DNA loops, the molecular functions of the third eukaryotic SMC complex, Smc5/6, remain largely unknown2. Using single-molecule imaging, we show that Smc5/6 forms DNA loops by extrusion. Upon ATP hydrolysis, Smc5/6 reels DNA symmetrically into loops at a force-dependent rate of one kilobase pair per second. Smc5/6 extrudes loops in the form of dimers, whereas monomeric Smc5/6 unidirectionally translocates along DNA. We also find that the subunits Nse5 and Nse6 (Nse5/6) act as negative regulators of loop extrusion. Nse5/6 inhibits loop-extrusion initiation by hindering Smc5/6 dimerization but has no influence on ongoing loop extrusion. Our findings reveal functions of Smc5/6 at the molecular level and establish DNA loop extrusion as a conserved mechanism among eukaryotic SMC complexes.
Collapse
Affiliation(s)
| | - Takaharu Kanno
- Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, Sweden
- Department of Biosciences and Nutrition, Karolinska Institutet, Huddinge, Sweden
| | - Miki Umeda Igarashi
- Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, Sweden
- Department of Biosciences and Nutrition, Karolinska Institutet, Huddinge, Sweden
| | - Mun Siong Loke
- Max Planck Institute of Biophysics, Frankfurt am Main, Germany
| | | | | | - Kristian Jeppsson
- Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, Sweden
- Department of Biosciences and Nutrition, Karolinska Institutet, Huddinge, Sweden
| | - Camilla Björkegren
- Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, Sweden.
- Department of Biosciences and Nutrition, Karolinska Institutet, Huddinge, Sweden.
| | - Eugene Kim
- Max Planck Institute of Biophysics, Frankfurt am Main, Germany.
| |
Collapse
|
13
|
Kabirova E, Nurislamov A, Shadskiy A, Smirnov A, Popov A, Salnikov P, Battulin N, Fishman V. Function and Evolution of the Loop Extrusion Machinery in Animals. Int J Mol Sci 2023; 24:ijms24055017. [PMID: 36902449 PMCID: PMC10003631 DOI: 10.3390/ijms24055017] [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: 02/07/2023] [Revised: 02/25/2023] [Accepted: 03/02/2023] [Indexed: 03/08/2023] Open
Abstract
Structural maintenance of chromosomes (SMC) complexes are essential proteins found in genomes of all cellular organisms. Essential functions of these proteins, such as mitotic chromosome formation and sister chromatid cohesion, were discovered a long time ago. Recent advances in chromatin biology showed that SMC proteins are involved in many other genomic processes, acting as active motors extruding DNA, which leads to the formation of chromatin loops. Some loops formed by SMC proteins are highly cell type and developmental stage specific, such as SMC-mediated DNA loops required for VDJ recombination in B-cell progenitors, or dosage compensation in Caenorhabditis elegans and X-chromosome inactivation in mice. In this review, we focus on the extrusion-based mechanisms that are common for multiple cell types and species. We will first describe an anatomy of SMC complexes and their accessory proteins. Next, we provide biochemical details of the extrusion process. We follow this by the sections describing the role of SMC complexes in gene regulation, DNA repair, and chromatin topology.
Collapse
Affiliation(s)
- Evelyn Kabirova
- Institute of Cytology and Genetics SB RAS, 630090 Novosibirsk, Russia
- Department of Natural Sciences, Novosibirsk State University, 630090 Novosibirsk, Russia
| | - Artem Nurislamov
- Institute of Cytology and Genetics SB RAS, 630090 Novosibirsk, Russia
- Department of Natural Sciences, Novosibirsk State University, 630090 Novosibirsk, Russia
| | - Artem Shadskiy
- Institute of Cytology and Genetics SB RAS, 630090 Novosibirsk, Russia
- Department of Natural Sciences, Novosibirsk State University, 630090 Novosibirsk, Russia
| | - Alexander Smirnov
- Institute of Cytology and Genetics SB RAS, 630090 Novosibirsk, Russia
- Department of Natural Sciences, Novosibirsk State University, 630090 Novosibirsk, Russia
| | - Andrey Popov
- Institute of Cytology and Genetics SB RAS, 630090 Novosibirsk, Russia
- Department of Natural Sciences, Novosibirsk State University, 630090 Novosibirsk, Russia
| | - Pavel Salnikov
- Institute of Cytology and Genetics SB RAS, 630090 Novosibirsk, Russia
- Department of Natural Sciences, Novosibirsk State University, 630090 Novosibirsk, Russia
| | - Nariman Battulin
- Institute of Cytology and Genetics SB RAS, 630090 Novosibirsk, Russia
- Department of Natural Sciences, Novosibirsk State University, 630090 Novosibirsk, Russia
| | - Veniamin Fishman
- Institute of Cytology and Genetics SB RAS, 630090 Novosibirsk, Russia
- Department of Natural Sciences, Novosibirsk State University, 630090 Novosibirsk, Russia
- Artificial Intelligence Research Institute (AIRI), 121108 Moscow, Russia
- Correspondence:
| |
Collapse
|
14
|
New opportunities in integrative structural modeling. Curr Opin Struct Biol 2022; 77:102488. [PMID: 36279817 DOI: 10.1016/j.sbi.2022.102488] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2022] [Revised: 09/13/2022] [Accepted: 09/15/2022] [Indexed: 12/14/2022]
Abstract
Integrative structural modeling enables structure determination of macromolecules and their complexes by integrating data from multiple sources. It has been successfully used to characterize macromolecular structures when a single structural biology technique was insufficient. Recent developments in cellular structural biology, including in-cell cryo-electron tomography and artificial intelligence-based structure prediction, have created new opportunities for integrative structural modeling. Here, we will review these opportunities along with the latest developments in integrative modeling methods and their applications. We also highlight open challenges and directions for further development.
Collapse
|
15
|
Chang JTH, Li S, Beckwitt EC, Than T, Haluska C, Chandanani J, O’Donnell ME, Zhao X, Liu S. Smc5/6's multifaceted DNA binding capacities stabilize branched DNA structures. Nat Commun 2022; 13:7179. [PMID: 36418314 PMCID: PMC9684126 DOI: 10.1038/s41467-022-34928-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Accepted: 11/11/2022] [Indexed: 11/25/2022] Open
Abstract
Smc5/6 is an evolutionarily conserved SMC complex with roles in DNA replication and repair, as well as in viral DNA restriction. Understanding its multiple functions has been hampered by a lack of mechanistic studies on how the Smc5/6 complex associates with different types of DNA. Here we address this question by simultaneously visualizing the behavior of Smc5/6 on three types of DNA, namely double-stranded (ds) DNA, single-stranded (ss) DNA, and junction DNA formed by juxtaposed ss- and dsDNA, using correlative single-molecule fluorescence and force microscopy. We find that Smc5/6 displays distinct behaviors toward different types of DNA, dynamically associating with dsDNA while stably binding to junction DNA. Mechanistically, both the Nse1-3-4 subcomplex and ATP binding enhance the complex's dsDNA association. In contrast, Smc5/6's assembly onto ssDNA emanating from junction DNA, which occurs even in the presence high-affinity ssDNA binders, is aided by Nse1-3-4, but not by ATP. Moreover, we show that Smc5/6 protects junction DNA stability by preventing ssDNA annealing. The multifaceted DNA association behaviors of Smc5/6 provide a framework for understanding its diverse functions in genome maintenance and viral DNA restriction.
Collapse
Affiliation(s)
- Jeremy T-H. Chang
- grid.134907.80000 0001 2166 1519Laboratory of Nanoscale Biophysics and Biochemistry, The Rockefeller University, New York, NY 10065 USA ,grid.51462.340000 0001 2171 9952Tri-Institutional MD-PhD Program, The Rockefeller University, Weill Cornell Medical College, and Memorial Sloan Kettering Cancer Center, New York, NY 10065 USA
| | - Shibai Li
- grid.51462.340000 0001 2171 9952Molecular Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065 USA
| | - Emily C. Beckwitt
- grid.134907.80000 0001 2166 1519Laboratory of DNA Replication, Howard Hughes Medical Institute, The Rockefeller University, New York, NY 10065 USA
| | - Thane Than
- grid.51462.340000 0001 2171 9952Molecular Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065 USA
| | - Cory Haluska
- grid.51462.340000 0001 2171 9952Molecular Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065 USA
| | - Joshua Chandanani
- grid.134907.80000 0001 2166 1519Laboratory of Nanoscale Biophysics and Biochemistry, The Rockefeller University, New York, NY 10065 USA
| | - Michael E. O’Donnell
- grid.134907.80000 0001 2166 1519Laboratory of DNA Replication, Howard Hughes Medical Institute, The Rockefeller University, New York, NY 10065 USA
| | - Xiaolan Zhao
- grid.51462.340000 0001 2171 9952Tri-Institutional MD-PhD Program, The Rockefeller University, Weill Cornell Medical College, and Memorial Sloan Kettering Cancer Center, New York, NY 10065 USA ,grid.51462.340000 0001 2171 9952Molecular Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065 USA
| | - Shixin Liu
- grid.134907.80000 0001 2166 1519Laboratory of Nanoscale Biophysics and Biochemistry, The Rockefeller University, New York, NY 10065 USA ,grid.51462.340000 0001 2171 9952Tri-Institutional MD-PhD Program, The Rockefeller University, Weill Cornell Medical College, and Memorial Sloan Kettering Cancer Center, New York, NY 10065 USA
| |
Collapse
|
16
|
Oravcová M, Nie M, Zilio N, Maeda S, Jami-Alahmadi Y, Lazzerini-Denchi E, Wohlschlegel JA, Ulrich HD, Otomo T, Boddy MN. The Nse5/6-like SIMC1-SLF2 complex localizes SMC5/6 to viral replication centers. eLife 2022; 11:e79676. [PMID: 36373674 PMCID: PMC9708086 DOI: 10.7554/elife.79676] [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: 04/22/2022] [Accepted: 11/09/2022] [Indexed: 11/16/2022] Open
Abstract
The human SMC5/6 complex is a conserved guardian of genome stability and an emerging component of antiviral responses. These disparate functions likely require distinct mechanisms of SMC5/6 regulation. In yeast, Smc5/6 is regulated by its Nse5/6 subunits, but such regulatory subunits for human SMC5/6 are poorly defined. Here, we identify a novel SMC5/6 subunit called SIMC1 that contains SUMO interacting motifs (SIMs) and an Nse5-like domain. We isolated SIMC1 from the proteomic environment of SMC5/6 within polyomavirus large T antigen (LT)-induced subnuclear compartments. SIMC1 uses its SIMs and Nse5-like domain to localize SMC5/6 to polyomavirus replication centers (PyVRCs) at SUMO-rich PML nuclear bodies. SIMC1's Nse5-like domain binds to the putative Nse6 orthologue SLF2 to form an anti-parallel helical dimer resembling the yeast Nse5/6 structure. SIMC1-SLF2 structure-based mutagenesis defines a conserved surface region containing the N-terminus of SIMC1's helical domain that regulates SMC5/6 localization to PyVRCs. Furthermore, SLF1, which recruits SMC5/6 to DNA lesions via its BRCT and ARD motifs, binds SLF2 analogously to SIMC1 and forms a separate Nse5/6-like complex. Thus, two Nse5/6-like complexes with distinct recruitment domains control human SMC5/6 localization.
Collapse
Affiliation(s)
- Martina Oravcová
- Department of Molecular Medicine, The Scripps Research InstituteLa JollaUnited States
| | - Minghua Nie
- Department of Molecular Medicine, The Scripps Research InstituteLa JollaUnited States
| | | | - Shintaro Maeda
- Department of Integrative Structural and Computational Biology, The Scripps Research InstituteLa JollaUnited States
| | - Yasaman Jami-Alahmadi
- Department of Biological Chemistry, David Geffen School of Medicine, University of California, Los AngelesLos AngelesUnited States
| | | | - James A Wohlschlegel
- Department of Biological Chemistry, David Geffen School of Medicine, University of California, Los AngelesLos AngelesUnited States
| | | | - Takanori Otomo
- Department of Integrative Structural and Computational Biology, The Scripps Research InstituteLa JollaUnited States
- San Diego Biomedical Research InstituteSan DiegoUnited States
| | - Michael N Boddy
- Department of Molecular Medicine, The Scripps Research InstituteLa JollaUnited States
| |
Collapse
|
17
|
Smc5/6 silences episomal transcription by a three-step function. Nat Struct Mol Biol 2022; 29:922-931. [PMID: 36097294 DOI: 10.1038/s41594-022-00829-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Accepted: 07/29/2022] [Indexed: 11/08/2022]
Abstract
In addition to its role in chromosome maintenance, the six-membered Smc5/6 complex functions as a restriction factor that binds to and transcriptionally silences viral and other episomal DNA. However, the underlying mechanism is unknown. Here, we show that transcriptional silencing by the human Smc5/6 complex is a three-step process. The first step is entrapment of the episomal DNA by a mechanism dependent on Smc5/6 ATPase activity and a function of its Nse4a subunit for which the Nse4b paralog cannot substitute. The second step results in Smc5/6 recruitment to promyelocytic leukemia nuclear bodies by SLF2 (the human ortholog of Nse6). The third step promotes silencing through a mechanism requiring Nse2 but not its SUMO ligase activity. By contrast, the related cohesin and condensin complexes fail to bind to or silence episomal DNA, indicating a property unique to Smc5/6.
Collapse
|
18
|
Hallett ST, Campbell Harry I, Schellenberger P, Zhou L, Cronin N, Baxter J, Etheridge T, Murray J, Oliver A. Cryo-EM structure of the Smc5/6 holo-complex. Nucleic Acids Res 2022; 50:9505-9520. [PMID: 35993814 PMCID: PMC9458440 DOI: 10.1093/nar/gkac692] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Revised: 07/14/2022] [Accepted: 07/30/2022] [Indexed: 01/06/2023] Open
Abstract
The Smc5/6 complex plays an essential role in the resolution of recombination intermediates formed during mitosis or meiosis, or as a result of the cellular response to replication stress. It also functions as a restriction factor preventing viral replication. Here, we report the cryogenic EM (cryo-EM) structure of the six-subunit budding yeast Smc5/6 holo-complex, reconstituted from recombinant proteins expressed in insect cells - providing both an architectural overview of the entire complex and an understanding of how the Nse1/3/4 subcomplex binds to the hetero-dimeric SMC protein core. In addition, we demonstrate that a region within the head domain of Smc5, equivalent to the 'W-loop' of Smc4 or 'F-loop' of Smc1, mediates an important interaction with Nse1. Notably, mutations that alter the surface-charge profile of the region of Nse1 which accepts the Smc5-loop, lead to a slow-growth phenotype and a global reduction in the chromatin-associated fraction of the Smc5/6 complex, as judged by single molecule localisation microscopy experiments in live yeast. Moreover, when taken together, our data indicates functional equivalence between the structurally unrelated KITE and HAWK accessory subunits associated with SMC complexes.
Collapse
Affiliation(s)
- Stephen T Hallett
- Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Falmer, UK
| | - Isabella Campbell Harry
- Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Falmer, UK
| | - Pascale Schellenberger
- Electron Microscopy Imaging Centre, School of Life Sciences, University of Sussex, Falmer, UK
| | - Lihong Zhou
- Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Falmer, UK
| | - Nora B Cronin
- London Consortium for CryoEM (LonCEM) Facility, The Francis Crick Institute, London, UK
| | - Jonathan Baxter
- Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Falmer, UK
| | - Thomas J Etheridge
- Correspondence may also be addressed to Thomas J. Etheridge. Tel: +44 1273 678123;
| | - Johanne M Murray
- Correspondence may also be addressed to Johanne M. Murray. Tel: +44 1273 877191;
| | - Antony W Oliver
- To whom correspondence should be addressed. Tel: +44 1273 678349;
| |
Collapse
|
19
|
Cryo-EM structure of DNA-bound Smc5/6 reveals DNA clamping enabled by multi-subunit conformational changes. Proc Natl Acad Sci U S A 2022; 119:e2202799119. [PMID: 35648833 PMCID: PMC9191643 DOI: 10.1073/pnas.2202799119] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The Smc5/6 complex plays multiple roles in DNA replication and repair. Its genome-protecting functions rely on its interaction with DNA; however, how this complex engages DNA is poorly understood. We report on a cryogenic electron microscopy structure of DNA-bound budding yeast Smc5/6 complex, revealing that its subunits form a clamp to encircle a double-helical DNA. We define the multi-subunit interactions forming the DNA clamp and the DNA binding sites distributed among subunits. We identify subunit transformations upon DNA capture and functional effects conferred by its multiple DNA contact sites. Our findings, in conjunction with studies on other structural maintenance of chromosomes (SMC) complexes, suggest a common SMC DNA-clamp mechanism with individual complex specific features that enable diverse genome organization and protection functions by SMC family complexes. Structural maintenance of chromosomes (SMC) complexes are essential for chromatin organization and functions throughout the cell cycle. The cohesin and condensin SMCs fold and tether DNA, while Smc5/6 directly promotes DNA replication and repair. The functions of SMCs rely on their abilities to engage DNA, but how Smc5/6 binds and translocates on DNA remains largely unknown. Here, we present a 3.8 Å cryogenic electron microscopy (cryo-EM) structure of DNA-bound Saccharomyces cerevisiae Smc5/6 complex containing five of its core subunits, including Smc5, Smc6, and the Nse1-3-4 subcomplex. Intricate interactions among these subunits support the formation of a clamp that encircles the DNA double helix. The positively charged inner surface of the clamp contacts DNA in a nonsequence-specific manner involving numerous DNA binding residues from four subunits. The DNA duplex is held up by Smc5 and 6 head regions and positioned between their coiled-coil arm regions, reflecting an engaged-head and open-arm configuration. The Nse3 subunit secures the DNA from above, while the hook-shaped Nse4 kleisin forms a scaffold connecting DNA and all other subunits. The Smc5/6 DNA clamp shares similarities with DNA-clamps formed by other SMCs but also exhibits differences that reflect its unique functions. Mapping cross-linking mass spectrometry data derived from DNA-free Smc5/6 to the DNA-bound Smc5/6 structure identifies multi-subunit conformational changes that enable DNA capture. Finally, mutational data from cells reveal distinct DNA binding contributions from each subunit to Smc5/6 chromatin association and cell fitness. In summary, our integrative study illuminates how a unique SMC complex engages DNA in supporting genome regulation.
Collapse
|
20
|
Nomidis SK, Carlon E, Gruber S, Marko JF. DNA tension-modulated translocation and loop extrusion by SMC complexes revealed by molecular dynamics simulations. Nucleic Acids Res 2022; 50:4974-4987. [PMID: 35474142 PMCID: PMC9122525 DOI: 10.1093/nar/gkac268] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2021] [Revised: 03/21/2022] [Accepted: 04/04/2022] [Indexed: 12/19/2022] Open
Abstract
Structural Maintenance of Chromosomes (SMC) complexes play essential roles in genome organization across all domains of life. To determine how the activities of these large (≈50 nm) complexes are controlled by ATP binding and hydrolysis, we developed a molecular dynamics model that accounts for conformational motions of the SMC and DNA. The model combines DNA loop capture with an ATP-induced ‘power stroke’ to translocate the SMC complex along DNA. This process is sensitive to DNA tension: at low tension (0.1 pN), the model makes loop-capture steps of average 60 nm and up to 200 nm along DNA (larger than the complex itself), while at higher tension, a distinct inchworm-like translocation mode appears. By tethering DNA to an experimentally-observed additional binding site (‘safety belt’), the model SMC complex can perform loop extrusion (LE). The dependence of LE on DNA tension is distinct for fixed DNA tension vs. fixed DNA end points: LE reversal occurs above 0.5 pN for fixed tension, while LE stalling without reversal occurs at about 2 pN for fixed end points. Our model matches recent experimental results for condensin and cohesin, and makes testable predictions for how specific structural variations affect SMC function.
Collapse
Affiliation(s)
- Stefanos K Nomidis
- Laboratory for Soft Matter and Biophysics, KU Leuven, Celestijnenlaan 200D, 3001 Leuven, Belgium
- Flemish Institute for Technological Research (VITO), Boeretang 200, B-2400 Mol, Belgium
| | - Enrico Carlon
- Laboratory for Soft Matter and Biophysics, KU Leuven, Celestijnenlaan 200D, 3001 Leuven, Belgium
| | - Stephan Gruber
- Départment de Microbiologie Fondamentale, Université de Lausanne, 1015 Lausanne, Switzerland
| | - John F Marko
- To whom correspondence should be addressed. Tel: +1 847 467 1276; Fax: +1 847 467 1380;
| |
Collapse
|
21
|
Yiu SPT, Guo R, Zerbe C, Weekes MP, Gewurz BE. Epstein-Barr virus BNRF1 destabilizes SMC5/6 cohesin complexes to evade its restriction of replication compartments. Cell Rep 2022; 38:110411. [PMID: 35263599 PMCID: PMC8981113 DOI: 10.1016/j.celrep.2022.110411] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Revised: 12/29/2021] [Accepted: 01/28/2022] [Indexed: 11/11/2022] Open
Abstract
Epstein-Barr virus (EBV) persistently infects people worldwide. Delivery of ∼170-kb EBV genomes to nuclei and use of nuclear membrane-less replication compartments (RCs) for their lytic cycle amplification necessitate evasion of intrinsic antiviral responses. Proteomics analysis indicates that, upon B cell infection or lytic reactivation, EBV depletes the cohesin SMC5/6, which has major roles in chromosome maintenance and DNA damage repair. The major tegument protein BNRF1 targets SMC5/6 complexes by a ubiquitin proteasome pathway dependent on calpain proteolysis and Cullin-7. In the absence of BNRF1, SMC5/6 associates with R-loop structures, including at the viral lytic origin of replication, and interferes with RC formation and encapsidation. CRISPR analysis identifies RC restriction roles of SMC5/6 components involved in DNA entrapment and SUMOylation. Our study highlights SMC5/6 as an intrinsic immune sensor and restriction factor for a human herpesvirus RC and has implications for the pathogenesis of EBV-associated cancers.
Collapse
Affiliation(s)
- Stephanie Pei Tung Yiu
- Division of Infectious Diseases, Department of Medicine, Brigham and Women's Hospital, 181 Longwood Avenue, Boston, MA 02115, USA; Harvard Graduate Program in Virology, Boston, MA 02115, USA; Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA; Department of Microbiology, Harvard Medical School, Boston, MA 02115, USA
| | - Rui Guo
- Division of Infectious Diseases, Department of Medicine, Brigham and Women's Hospital, 181 Longwood Avenue, Boston, MA 02115, USA; Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA; Department of Microbiology, Harvard Medical School, Boston, MA 02115, USA
| | - Cassie Zerbe
- Cambridge Institute for Medical Research, University of Cambridge, Hills Road, Cambridge CB2 0XY, UK
| | - Michael P Weekes
- Cambridge Institute for Medical Research, University of Cambridge, Hills Road, Cambridge CB2 0XY, UK
| | - Benjamin E Gewurz
- Division of Infectious Diseases, Department of Medicine, Brigham and Women's Hospital, 181 Longwood Avenue, Boston, MA 02115, USA; Harvard Graduate Program in Virology, Boston, MA 02115, USA; Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA; Department of Microbiology, Harvard Medical School, Boston, MA 02115, USA.
| |
Collapse
|
22
|
Mechanisms of DNA Mobilization and Sequestration. Genes (Basel) 2022; 13:genes13020352. [PMID: 35205396 PMCID: PMC8872102 DOI: 10.3390/genes13020352] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Revised: 02/10/2022] [Accepted: 02/12/2022] [Indexed: 12/04/2022] Open
Abstract
The entire genome becomes mobilized following DNA damage. Understanding the mechanisms that act at the genome level requires that we embrace experimental and computational strategies to capture the behavior of the long-chain DNA polymer, which is the building block for the chromosome. Long-chain polymers exhibit constrained, sub-diffusive motion in the nucleus. Cross-linking proteins, including cohesin and condensin, have a disproportionate effect on genome organization in their ability to stabilize transient interactions. Cross-linking proteins can segregate the genome into sub-domains through polymer–polymer phase separation (PPPS) and can drive the formation of gene clusters through small changes in their binding kinetics. Principles from polymer physics provide a means to unravel the mysteries hidden in the chains of life.
Collapse
|
23
|
Klykov O, Kopylov M, Carragher B, Heck AJ, Noble AJ, Scheltema RA. Label-free visual proteomics: Coupling MS- and EM-based approaches in structural biology. Mol Cell 2022; 82:285-303. [PMID: 35063097 PMCID: PMC8842845 DOI: 10.1016/j.molcel.2021.12.027] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2021] [Revised: 12/14/2021] [Accepted: 12/20/2021] [Indexed: 01/22/2023]
Abstract
Combining diverse experimental structural and interactomic methods allows for the construction of comprehensible molecular encyclopedias of biological systems. Typically, this involves merging several independent approaches that provide complementary structural and functional information from multiple perspectives and at different resolution ranges. A particularly potent combination lies in coupling structural information from cryoelectron microscopy or tomography (cryo-EM or cryo-ET) with interactomic and structural information from mass spectrometry (MS)-based structural proteomics. Cryo-EM/ET allows for sub-nanometer visualization of biological specimens in purified and near-native states, while MS provides bioanalytical information for proteins and protein complexes without introducing additional labels. Here we highlight recent achievements in protein structure and interactome determination using cryo-EM/ET that benefit from additional MS analysis. We also give our perspective on how combining cryo-EM/ET and MS will continue bridging gaps between molecular and cellular studies by capturing and describing 3D snapshots of proteomes and interactomes.
Collapse
Affiliation(s)
- Oleg Klykov
- National Center for In-situ Tomographic Ultramicroscopy, Simons Electron Microscopy Center, New York Structural Biology Center, New York, NY, USA,Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY, USA
| | - Mykhailo Kopylov
- National Center for In-situ Tomographic Ultramicroscopy, Simons Electron Microscopy Center, New York Structural Biology Center, New York, NY, USA
| | - Bridget Carragher
- National Center for In-situ Tomographic Ultramicroscopy, Simons Electron Microscopy Center, New York Structural Biology Center, New York, NY, USA,Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY, USA
| | - Albert J.R. Heck
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, 3584 CH Utrecht, The Netherlands,Netherlands Proteomics Center, 3584 CH Utrecht, The Netherlands
| | - Alex J Noble
- National Center for In-situ Tomographic Ultramicroscopy, Simons Electron Microscopy Center, New York Structural Biology Center, New York, NY, USA,Corresponding author for cryo-EM/ET/FIB-SEM: Alex J. Noble, tel: (+1) 212-939-0660;
| | - Richard A. Scheltema
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, 3584 CH Utrecht, The Netherlands,Netherlands Proteomics Center, 3584 CH Utrecht, The Netherlands,Corresponding author for MS: Richard A. Scheltema, tel: (+31) 30 253 6804;
| |
Collapse
|
24
|
Varejão N, Lascorz J, Codina-Fabra J, Bellí G, Borràs-Gas H, Torres-Rosell J, Reverter D. Structural basis for the E3 ligase activity enhancement of yeast Nse2 by SUMO-interacting motifs. Nat Commun 2021; 12:7013. [PMID: 34853311 PMCID: PMC8636563 DOI: 10.1038/s41467-021-27301-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Accepted: 11/09/2021] [Indexed: 01/02/2023] Open
Abstract
Post-translational modification of proteins by ubiquitin and ubiquitin-like modifiers, such as SUMO, are key events in protein homeostasis or DNA damage response. Smc5/6 is a nuclear multi-subunit complex that participates in the recombinational DNA repair processes and is required in the maintenance of chromosome integrity. Nse2 is a subunit of the Smc5/6 complex that possesses SUMO E3 ligase activity by the presence of a SP-RING domain that activates the E2~SUMO thioester for discharge on the substrate. Here we present the crystal structure of the SUMO E3 ligase Nse2 in complex with an E2-SUMO thioester mimetic. In addition to the interface between the SP-RING domain and the E2, the complex reveals how two SIM (SUMO-Interacting Motif) -like motifs in Nse2 are restructured upon binding the donor and E2-backside SUMO during the E3-dependent discharge reaction. Both SIM interfaces are essential in the activity of Nse2 and are required to cope with DNA damage. Nse2 is a SUMO E3 ligase component of the Smc5/6 multisubunit complex involved in the DNA repair and chromosome integrity. Here, the structure of the Nse2 in complex with an E2-SUMO thioester mimetic reveals the combined action of two SIM motifs during the E3- dependent conjugation reaction.
Collapse
Affiliation(s)
- Nathalia Varejão
- Institut de Biotecnologia i de Biomedicina (IBB) and Dept. de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, 08193, Bellaterra, Spain
| | - Jara Lascorz
- Institut de Biotecnologia i de Biomedicina (IBB) and Dept. de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, 08193, Bellaterra, Spain
| | - Joan Codina-Fabra
- IRBLLEIDA, Dept. Ciències Mèdiques Bàsiques, Universitat de Lleida, Lleida, Spain
| | - Gemma Bellí
- IRBLLEIDA, Dept. Ciències Mèdiques Bàsiques, Universitat de Lleida, Lleida, Spain
| | - Helena Borràs-Gas
- Institut de Biotecnologia i de Biomedicina (IBB) and Dept. de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, 08193, Bellaterra, Spain
| | - Jordi Torres-Rosell
- IRBLLEIDA, Dept. Ciències Mèdiques Bàsiques, Universitat de Lleida, Lleida, Spain
| | - David Reverter
- Institut de Biotecnologia i de Biomedicina (IBB) and Dept. de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, 08193, Bellaterra, Spain.
| |
Collapse
|
25
|
Piersimoni L, Kastritis PL, Arlt C, Sinz A. Cross-Linking Mass Spectrometry for Investigating Protein Conformations and Protein-Protein Interactions─A Method for All Seasons. Chem Rev 2021; 122:7500-7531. [PMID: 34797068 DOI: 10.1021/acs.chemrev.1c00786] [Citation(s) in RCA: 83] [Impact Index Per Article: 27.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Mass spectrometry (MS) has become one of the key technologies of structural biology. In this review, the contributions of chemical cross-linking combined with mass spectrometry (XL-MS) for studying three-dimensional structures of proteins and for investigating protein-protein interactions are outlined. We summarize the most important cross-linking reagents, software tools, and XL-MS workflows and highlight prominent examples for characterizing proteins, their assemblies, and interaction networks in vitro and in vivo. Computational modeling plays a crucial role in deriving 3D-structural information from XL-MS data. Integrating XL-MS with other techniques of structural biology, such as cryo-electron microscopy, has been successful in addressing biological questions that to date could not be answered. XL-MS is therefore expected to play an increasingly important role in structural biology in the future.
Collapse
Affiliation(s)
- Lolita Piersimoni
- Department of Pharmaceutical Chemistry & Bioanalytics, Institute of Pharmacy, Kurt-Mothes-Strasse 3, D-06120 Halle (Saale), Germany.,Center for Structural Mass Spectrometry, Kurt-Mothes-Strasse 3, D-06120 Halle (Saale), Germany
| | - Panagiotis L Kastritis
- Interdisciplinary Research Center HALOmem, Charles Tanford Protein Center, Kurt-Mothes-Strasse 3a, D-06120 Halle (Saale), Germany.,Institute of Biochemistry and Biotechnology, Martin Luther University Halle-Wittenberg, Kurt-Mothes-Strasse 3, D-06120 Halle (Saale), Germany.,Biozentrum, Weinbergweg 22, D-06120 Halle (Saale), Germany
| | - Christian Arlt
- Department of Pharmaceutical Chemistry & Bioanalytics, Institute of Pharmacy, Kurt-Mothes-Strasse 3, D-06120 Halle (Saale), Germany.,Center for Structural Mass Spectrometry, Kurt-Mothes-Strasse 3, D-06120 Halle (Saale), Germany
| | - Andrea Sinz
- Department of Pharmaceutical Chemistry & Bioanalytics, Institute of Pharmacy, Kurt-Mothes-Strasse 3, D-06120 Halle (Saale), Germany.,Center for Structural Mass Spectrometry, Kurt-Mothes-Strasse 3, D-06120 Halle (Saale), Germany
| |
Collapse
|
26
|
A Framework for Stochastic Optimization of Parameters for Integrative Modeling of Macromolecular Assemblies. Life (Basel) 2021; 11:life11111183. [PMID: 34833059 PMCID: PMC8618978 DOI: 10.3390/life11111183] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Revised: 10/20/2021] [Accepted: 10/23/2021] [Indexed: 01/15/2023] Open
Abstract
Integrative modeling of macromolecular assemblies requires stochastic sampling, for example, via MCMC (Markov Chain Monte Carlo), since exhaustively enumerating all structural degrees of freedom is infeasible. MCMC-based methods usually require tuning several parameters, such as the move sizes for coarse-grained beads and rigid bodies, for sampling to be efficient and accurate. Currently, these parameters are tuned manually. To automate this process, we developed a general heuristic for derivative-free, global, stochastic, parallel, multiobjective optimization, termed StOP (Stochastic Optimization of Parameters) and applied it to optimize sampling-related parameters for the Integrative Modeling Platform (IMP). Given an integrative modeling setup, list of parameters to optimize, their domains, metrics that they influence, and the target ranges of these metrics, StOP produces the optimal values of these parameters. StOP is adaptable to the available computing capacity and converges quickly, allowing for the simultaneous optimization of a large number of parameters. However, it is not efficient at high dimensions and not guaranteed to find optima in complex landscapes. We demonstrate its performance on several examples of random functions, as well as on two integrative modeling examples, showing that StOP enhances the efficiency of sampling the posterior distribution, resulting in more good-scoring models and better sampling precision.
Collapse
|
27
|
Abstract
The specialized two-stage meiotic cell division program halves a cell's chromosome complement in preparation for sexual reproduction. This reduction in ploidy requires that in meiotic prophase, each pair of homologous chromosomes (homologs) identify one another and form physical links through DNA recombination. Here, we review recent advances in understanding the complex morphological changes that chromosomes undergo during meiotic prophase to promote homolog identification and crossing over. We focus on the structural maintenance of chromosomes (SMC) family cohesin complexes and the meiotic chromosome axis, which together organize chromosomes and promote recombination. We then discuss the architecture and dynamics of the conserved synaptonemal complex (SC), which assembles between homologs and mediates local and global feedback to ensure high fidelity in meiotic recombination. Finally, we discuss exciting new advances, including mechanisms for boosting recombination on particular chromosomes or chromosomal domains and the implications of a new liquid crystal model for SC assembly and structure. Expected final online publication date for the Annual Review of Genetics, Volume 55 is November 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
Collapse
Affiliation(s)
- Sarah N Ur
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, California 92093, USA; ,
| | - Kevin D Corbett
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, California 92093, USA; , .,Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093, USA
| |
Collapse
|
28
|
Taschner M, Basquin J, Steigenberger B, Schäfer IB, Soh YM, Basquin C, Lorentzen E, Räschle M, Scheltema RA, Gruber S. Nse5/6 inhibits the Smc5/6 ATPase and modulates DNA substrate binding. EMBO J 2021; 40:e107807. [PMID: 34191293 PMCID: PMC8327961 DOI: 10.15252/embj.2021107807] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Revised: 06/10/2021] [Accepted: 06/11/2021] [Indexed: 12/23/2022] Open
Abstract
Eukaryotic cells employ three SMC (structural maintenance of chromosomes) complexes to control DNA folding and topology. The Smc5/6 complex plays roles in DNA repair and in preventing the accumulation of deleterious DNA junctions. To elucidate how specific features of Smc5/6 govern these functions, we reconstituted the yeast holo‐complex. We found that the Nse5/6 sub‐complex strongly inhibited the Smc5/6 ATPase by preventing productive ATP binding. This inhibition was relieved by plasmid DNA binding but not by short linear DNA, while opposing effects were observed without Nse5/6. We uncovered two binding sites for Nse5/6 on Smc5/6, based on an Nse5/6 crystal structure and cross‐linking mass spectrometry data. One binding site is located at the Smc5/6 arms and one at the heads, the latter likely exerting inhibitory effects on ATP hydrolysis. Cysteine cross‐linking demonstrated that the interaction with Nse5/6 anchored the ATPase domains in a non‐productive state, which was destabilized by ATP and DNA. Under similar conditions, the Nse4/3/1 module detached from the ATPase. Altogether, we show how DNA substrate selection is modulated by direct inhibition of the Smc5/6 ATPase by Nse5/6.
Collapse
Affiliation(s)
- Michael Taschner
- Department of Fundamental Microbiology (DMF), Faculty of Biology and Medicine (FBM), University of Lausanne (UNIL), Lausanne, Switzerland
| | - Jérôme Basquin
- Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Barbara Steigenberger
- Max Planck Institute of Biochemistry, Martinsried, Germany.,Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht, The Netherlands.,Netherlands Proteomics Centre, Utrecht, The Netherlands
| | | | - Young-Min Soh
- Department of Fundamental Microbiology (DMF), Faculty of Biology and Medicine (FBM), University of Lausanne (UNIL), Lausanne, Switzerland
| | - Claire Basquin
- Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Esben Lorentzen
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
| | - Markus Räschle
- Molecular Genetics, University of Kaiserslautern, Kaiserslautern, Germany
| | - Richard A Scheltema
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht, The Netherlands.,Netherlands Proteomics Centre, Utrecht, The Netherlands
| | - Stephan Gruber
- Department of Fundamental Microbiology (DMF), Faculty of Biology and Medicine (FBM), University of Lausanne (UNIL), Lausanne, Switzerland
| |
Collapse
|