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de Vivo A, Sanchez A, Yegres J, Kim J, Emly S, Kee Y. The OTUD5-UBR5 complex regulates FACT-mediated transcription at damaged chromatin. Nucleic Acids Res 2019; 47:729-746. [PMID: 30508113 PMCID: PMC6344881 DOI: 10.1093/nar/gky1219] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Accepted: 11/22/2018] [Indexed: 12/16/2022] Open
Abstract
Timely stalling and resumption of RNA polymerases at damaged chromatin are actively regulated processes. Prior work showed an importance of FACT histone chaperone in such process. Here we provide a new role of OTUD5 deubiquitinase in the FACT-dependent process. Through a DUB RNAi screen, we found OTUD5 as a specific stabilizer of the UBR5 E3 ligase. OTUD5 localizes to DNA double strand breaks (DSBs), interacts with UBR5 and represses the RNA Pol II elongation and RNA synthesis. OTUD5 co-localizes and interacts with the FACT component SPT16 and antagonizes the histone H2A deposition at DSB lesions. OTUD5 interacts with UBR5 and SPT16 independently through two distinct regions, and both interactions are necessary for arresting the Pol II elongation at lesions. These analyses suggested that the catalytic (through UBR5 stabilization) as well as scaffolding (through FACT binding) activities of OTUD5 are involved in the FACT-dependent transcription. We found that a cancer-associated missense mutation within the OTUD5 Ubiquitin Interacting Motif (UIM) abrogates the FACT association and the Pol II arrest, providing a possible link between the transcriptional regulation and tumor suppression. Our work establishes OTUD5 as a new regulator of the DNA damage response, and provides an insight into the FACT-dependent transcription at damaged chromatin.
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Affiliation(s)
- Angelo de Vivo
- Department of Cell Biology, Microbiology, and Molecular Biology, College of Arts and Sciences, University of South Florida, Tampa, FL 33620, USA
| | - Anthony Sanchez
- Department of Cell Biology, Microbiology, and Molecular Biology, College of Arts and Sciences, University of South Florida, Tampa, FL 33620, USA
| | - Jose Yegres
- Department of Cell Biology, Microbiology, and Molecular Biology, College of Arts and Sciences, University of South Florida, Tampa, FL 33620, USA
| | - Jeonghyeon Kim
- Department of Cell Biology, Microbiology, and Molecular Biology, College of Arts and Sciences, University of South Florida, Tampa, FL 33620, USA
| | - Sylvia Emly
- Department of Cell Biology, Microbiology, and Molecular Biology, College of Arts and Sciences, University of South Florida, Tampa, FL 33620, USA
| | - Younghoon Kee
- Department of Cell Biology, Microbiology, and Molecular Biology, College of Arts and Sciences, University of South Florida, Tampa, FL 33620, USA
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52
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The histone chaperoning pathway: from ribosome to nucleosome. Essays Biochem 2019; 63:29-43. [PMID: 31015382 PMCID: PMC6484783 DOI: 10.1042/ebc20180055] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Revised: 02/26/2019] [Accepted: 02/28/2019] [Indexed: 12/15/2022]
Abstract
Nucleosomes represent the fundamental repeating unit of eukaryotic DNA, and comprise eight core histones around which DNA is wrapped in nearly two superhelical turns. Histones do not have the intrinsic ability to form nucleosomes; rather, they require an extensive repertoire of interacting proteins collectively known as ‘histone chaperones’. At a fundamental level, it is believed that histone chaperones guide the assembly of nucleosomes through preventing non-productive charge-based aggregates between the basic histones and acidic cellular components. At a broader level, histone chaperones influence almost all aspects of chromatin biology, regulating histone supply and demand, governing histone variant deposition, maintaining functional chromatin domains and being co-factors for histone post-translational modifications, to name a few. In this essay we review recent structural insights into histone-chaperone interactions, explore evidence for the existence of a histone chaperoning ‘pathway’ and reconcile how such histone-chaperone interactions may function thermodynamically to assemble nucleosomes and maintain chromatin homeostasis.
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53
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Padavannil A, Sarkar P, Kim SJ, Cagatay T, Jiou J, Brautigam CA, Tomchick DR, Sali A, D'Arcy S, Chook YM. Importin-9 wraps around the H2A-H2B core to act as nuclear importer and histone chaperone. eLife 2019; 8:e43630. [PMID: 30855230 PMCID: PMC6453568 DOI: 10.7554/elife.43630] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2018] [Accepted: 03/09/2019] [Indexed: 01/29/2023] Open
Abstract
We report the crystal structure of nuclear import receptor Importin-9 bound to its cargo, the histones H2A-H2B. Importin-9 wraps around the core, globular region of H2A-H2B to form an extensive interface. The nature of this interface coupled with quantitative analysis of deletion mutants of H2A-H2B suggests that the NLS-like sequences in the H2A-H2B tails play a minor role in import. Importin-9•H2A-H2B is reminiscent of interactions between histones and histone chaperones in that it precludes H2A-H2B interactions with DNA and H3-H4 as seen in the nucleosome. Like many histone chaperones, which prevent inappropriate non-nucleosomal interactions, Importin-9 also sequesters H2A-H2B from DNA. Importin-9 appears to act as a storage chaperone for H2A-H2B while escorting it to the nucleus. Surprisingly, RanGTP does not dissociate Importin-9•H2A-H2B but assembles into a RanGTP•Importin-9•H2A-H2B complex. The presence of Ran in the complex, however, modulates Imp9-H2A-H2B interactions to facilitate its dissociation by DNA and assembly into a nucleosome.
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Affiliation(s)
- Abhilash Padavannil
- Department of PharmacologyUniversity of Texas Southwestern Medical CenterDallasUnited States
| | - Prithwijit Sarkar
- Department of Biological SciencesUniversity of Texas at DallasRichardsonUnited States
| | - Seung Joong Kim
- Department of PhysicsKorea Advanced Institute of Science and Technology (KAIST)DaejeonKorea
| | - Tolga Cagatay
- Department of PharmacologyUniversity of Texas Southwestern Medical CenterDallasUnited States
| | - Jenny Jiou
- Department of PharmacologyUniversity of Texas Southwestern Medical CenterDallasUnited States
| | - Chad A Brautigam
- Department of BiophysicsUniversity of Texas Southwestern Medical CenterDallasUnited States
| | - Diana R Tomchick
- Department of BiophysicsUniversity of Texas Southwestern Medical CenterDallasUnited States
| | - Andrej Sali
- Department of Bioengineering and Therapeutic Sciences, California Institute for Quantitative BiosciencesUniversity of California, San FranciscoSan FranciscoUnited States
- Department of Pharmaceutical Chemistry, California Institute for Quantitative BiosciencesUniversity of California, San FranciscoSan FranciscoUnited states
| | - Sheena D'Arcy
- Department of Chemistry and BiochemistryUniversity of Texas at DallasRichardsonUnited States
| | - Yuh Min Chook
- Department of PharmacologyUniversity of Texas Southwestern Medical CenterDallasUnited States
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54
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Transcription-driven chromatin repression of Intragenic transcription start sites. PLoS Genet 2019; 15:e1007969. [PMID: 30707695 PMCID: PMC6373976 DOI: 10.1371/journal.pgen.1007969] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Revised: 02/13/2019] [Accepted: 01/16/2019] [Indexed: 12/31/2022] Open
Abstract
Progression of RNA polymerase II (RNAPII) transcription relies on the appropriately positioned activities of elongation factors. The resulting profile of factors and chromatin signatures along transcription units provides a “positional information system” for transcribing RNAPII. Here, we investigate a chromatin-based mechanism that suppresses intragenic initiation of RNAPII transcription. We demonstrate that RNAPII transcription across gene promoters represses their function in plants. This repression is characterized by reduced promoter-specific molecular signatures and increased molecular signatures associated with RNAPII elongation. The conserved FACT histone chaperone complex is required for this repression mechanism. Genome-wide Transcription Start Site (TSS) mapping reveals thousands of discrete intragenic TSS positions in fact mutants, including downstream promoters that initiate alternative transcript isoforms. We find that histone H3 lysine 4 mono-methylation (H3K4me1), an Arabidopsis RNAPII elongation signature, is enriched at FACT-repressed intragenic TSSs. Our analyses suggest that FACT is required to repress intragenic TSSs at positions that are in part characterized by elevated H3K4me1 levels. In sum, conserved and plant-specific chromatin features correlate with the co-transcriptional repression of intragenic TSSs. Our insights into TSS repression by RNAPII transcription promise to inform the regulation of alternative transcript isoforms and the characterization of gene regulation through the act of pervasive transcription across eukaryotic genomes. Genes represent DNA elements that are transcribed into mRNA. However, the position where transcription actually starts can be dynamically regulated to expand the diversity of RNA isoforms produced from a single gene. Functionally, alternative Transcription Start Sites (TSSs) may generate protein isoforms with differing N-terminal regions and distinct cellular functions. In plants, light signaling regulates protein isoforms largely through regulated TSS selection, emphasizing the biological significance of this mechanism. Despite the importance of alternative TSS selection, little is known about the underlying molecular mechanisms. Here, we characterize for the first time how transcription initiation from an upstream promoter represses alternative downstream promoter activity in plants. This repression mechanism is associated with chromatin changes that are required to maintain precise gene expression control. Specific chromatin signatures are established during transcription via dynamic interactions between the transcription machinery and associated factors. The conserved histone chaperone complex FACT is one such factor involved in regulating the chromatin environment along genes during transcription. We find that mutant plants with reduced FACT activity specifically initiate transcription from thousands of intragenic positions, thus expanding RNA isoform diversity. Overall, our study reveals conserved and plant-specific chromatin features associated with the co-transcriptional repression of downstream intragenic TSSs. These findings promise to help inform the molecular mechanism underlying environmentally-triggered TSS regulation in plants.
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55
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Ricketts MD, Han J, Szurgot MR, Marmorstein R. Molecular basis for chromatin assembly and modification by multiprotein complexes. Protein Sci 2018; 28:329-343. [PMID: 30350439 DOI: 10.1002/pro.3535] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Revised: 10/05/2018] [Accepted: 10/08/2018] [Indexed: 12/29/2022]
Abstract
Epigenetic regulation of the chromatin landscape is often orchestrated through modulation of nucleosomes. Nucleosomes are composed of two copies each of the four core histones, H2A, H2B, H3, and H4, wrapped in ~150 bp of DNA. We focus this review on recent structural studies that further elucidate the mechanisms used by macromolecular complexes to mediate histone modification and nucleosome assembly. Nucleosome assembly, spacing, and variant histone incorporation are coordinated by chromatin remodeler and histone chaperone complexes. Several recent structural studies highlight how disparate families of histone chaperones and chromatin remodelers share similar features that underlie how they interact with their respective histone or nucleosome substrates. Post-translational modification of histone residues is mediated by enzymatic subunits within large complexes. Until recently, relatively little was known about how association with auxiliary subunits serves to modulate the activity and specificity of the enzymatic subunit. Analysis of several recent structures highlights the different modes that auxiliary subunits use to influence enzymatic activity or direct specificity toward individual histone residues.
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Affiliation(s)
- M Daniel Ricketts
- Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, 19104.,Abramson Family Cancer Research Institute, University of Pennsylvania, Philadelphia, Pennsylvania, 19104
| | - Joseph Han
- Department of Chemistry Graduate Group, University of Pennsylvania, Philadelphia, Pennsylvania, 19104
| | - Mary R Szurgot
- Graduate Group in Biochemistry and Molecular Biophysics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, 19104
| | - Ronen Marmorstein
- Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, 19104.,Abramson Family Cancer Research Institute, University of Pennsylvania, Philadelphia, Pennsylvania, 19104.,Department of Chemistry Graduate Group, University of Pennsylvania, Philadelphia, Pennsylvania, 19104.,Graduate Group in Biochemistry and Molecular Biophysics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, 19104
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56
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Jiang H, Xu S, Chen Y, Li H, Tian L, Zhou H, Zhao Z, Yang C, Zhong Z, Cai G, Su D. The structural basis of human Spt16 N-terminal domain interaction with histone (H3-H4) 2 tetramer. Biochem Biophys Res Commun 2018; 508:864-870. [PMID: 30528735 DOI: 10.1016/j.bbrc.2018.11.150] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2018] [Accepted: 11/21/2018] [Indexed: 02/05/2023]
Abstract
FACT (Facilitates Chromatin Transactions) is a heterodimeric protein complex involved in RNA polymerase II transcription elongation, playing essential roles in chromatin remodeling during transcription, replication, and DNA damage repair. The FACT subunit hSpt16 is essential for nucleosome reorganization. The N-terminal domain of hSpt16 (hSpt16-NTD) was recently described as a histone (H3-H4)2-binding domain; however, its mode of interaction remains unknown. In this study, we solved the structure of hSpt16-NTD437 at 2.19 Å and found that a long-disordered region (hSpt16-LDR), after the main body of hSpt16-NTD, is a novel histone-binding motif. Furthermore, hSpt16-LDR interaction with (H3-H4)2 is H3 N-terminal tail-independent. Therefore, Spt16-NTD is a histone H3-H4-specific binding domain with a distinct mechanism of interaction between histones and histone chaperones.
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Affiliation(s)
- Hua Jiang
- State Key Lab of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan, 610041, PR China
| | - Sidan Xu
- State Key Lab of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan, 610041, PR China
| | - Yiping Chen
- State Key Lab of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan, 610041, PR China
| | - Huiyan Li
- State Key Lab of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan, 610041, PR China
| | - Lu Tian
- State Key Lab of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan, 610041, PR China
| | - Hongying Zhou
- Department of Human Anatomy, West China School of Basic Medical Sciences and Forensic Medicine, Sichuan University, Chengdu, PR China
| | - Zhiwei Zhao
- Department of Human Anatomy, West China School of Basic Medical Sciences and Forensic Medicine, Sichuan University, Chengdu, PR China
| | - Cheng Yang
- Key Laboratory of Green Chemistry & Technology, College of Chemistry, Sichuan University, Chengdu, PR China
| | - Zhihui Zhong
- Laboratory of Nonhuman Primate Disease Modeling Research, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, PR China
| | - Guocai Cai
- Department of Cardiovascular Medicine, The Third Hospital of MianYang (Sichuan Mental Health Center), Sichuan, 621000, PR China
| | - Dan Su
- State Key Lab of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan, 610041, PR China.
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57
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Chang HW, Valieva ME, Safina A, Chereji RV, Wang J, Kulaeva OI, Morozov AV, Kirpichnikov MP, Feofanov AV, Gurova KV, Studitsky VM. Mechanism of FACT removal from transcribed genes by anticancer drugs curaxins. SCIENCE ADVANCES 2018; 4:eaav2131. [PMID: 30417101 PMCID: PMC6221510 DOI: 10.1126/sciadv.aav2131] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2018] [Accepted: 10/10/2018] [Indexed: 05/21/2023]
Abstract
Human FACT (facilitates chromatin transcription) is a multifunctional protein complex that has histone chaperone activity and facilitates nucleosome survival and transcription through chromatin. Anticancer drugs curaxins induce FACT trapping on chromatin of cancer cells (c-trapping), but the mechanism of c-trapping is not fully understood. Here, we show that in cancer cells, FACT is highly enriched within the bodies of actively transcribed genes. Curaxin-dependent c-trapping results in redistribution of FACT from the transcribed chromatin regions to other genomic loci. Using a combination of biochemical and biophysical approaches, we have demonstrated that FACT is bound to and unfolds nucleosomes in the presence of curaxins. This tight binding to the nucleosome results in inhibition of FACT-dependent transcription in vitro in the presence of both curaxins and competitor chromatin, suggesting a mechanism of FACT trapping on bulk nucleosomes (n-trapping).
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Affiliation(s)
- Han-Wen Chang
- Fox Chase Cancer Center, Philadelphia, PA 19111, USA
| | - Maria E. Valieva
- Biology Faculty, Lomonosov Moscow State University, 119992 Moscow, Russia
- Max Planck Institute for Molecular Genetics, Ihnestraße 63-73, 14195 Berlin, Germany
| | - Alfiya Safina
- Department of Cell Stress Biology, Roswell Park Cancer Institute, Buffalo, NY 14263, USA
| | - Răzvan V. Chereji
- Eunice Kennedy Shriver National Institute for Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Jianmin Wang
- Department of Bioinformatics, Roswell Park Cancer Institute, Elm and Carlton Streets, Buffalo, NY 14263, USA
| | | | - Alexandre V. Morozov
- Department of Physics and Astronomy and Center for Quantitative Biology, Rutgers University, Piscataway, NJ 08854, USA
| | - Mikhail P. Kirpichnikov
- Biology Faculty, Lomonosov Moscow State University, 119992 Moscow, Russia
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, 117997 Moscow, Russia
| | - Alexey V. Feofanov
- Biology Faculty, Lomonosov Moscow State University, 119992 Moscow, Russia
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, 117997 Moscow, Russia
| | - Katerina V. Gurova
- Department of Cell Stress Biology, Roswell Park Cancer Institute, Buffalo, NY 14263, USA
| | - Vasily M. Studitsky
- Fox Chase Cancer Center, Philadelphia, PA 19111, USA
- Biology Faculty, Lomonosov Moscow State University, 119992 Moscow, Russia
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58
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Martin BJE, Chruscicki AT, Howe LJ. Transcription Promotes the Interaction of the FAcilitates Chromatin Transactions (FACT) Complex with Nucleosomes in Saccharomyces cerevisiae. Genetics 2018; 210:869-881. [PMID: 30237209 PMCID: PMC6218215 DOI: 10.1534/genetics.118.301349] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Accepted: 09/06/2018] [Indexed: 12/20/2022] Open
Abstract
The FACT (FAcilitates Chromatin Transactions) complex is a conserved complex that maintains chromatin structure on transcriptionally active genes. Consistent with this, FACT is enriched on highly expressed genes, but how it is targeted to these regions is unknown. In vitro, FACT binds destabilized nucleosomes, supporting the hypothesis that FACT is targeted to transcribed chromatin through recognition of RNA polymerase (RNAP)-disrupted nucleosomes. In this study, we used high-resolution analysis of FACT occupancy in Saccharomyces cerevisiae to test this hypothesis. We demonstrate that FACT interacts with nucleosomes in vivo and that its interaction with chromatin is dependent on transcription by any of the three RNAPs. Deep sequencing of micrococcal nuclease-resistant fragments shows that FACT-bound nucleosomes exhibit differing nuclease sensitivity compared to bulk chromatin, consistent with a modified nucleosome structure being the preferred ligand for this complex. Interestingly, a subset of FACT-bound nucleosomes may be "overlapping dinucleosomes," in which one histone octamer invades the ∼147-bp territory normally occupied by the adjacent nucleosome. While the differing nuclease sensitivity of FACT-bound nucleosomes could also be explained by the demonstrated ability of FACT to alter nucleosome structure, transcription inhibition restores nuclease resistance, suggesting that it is not due to FACT interaction alone. Collectively, these results are consistent with a model in which FACT is targeted to transcribed genes through preferential interaction with RNAP-disrupted nucleosomes.
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Affiliation(s)
- Benjamin J E Martin
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - Adam T Chruscicki
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - LeAnn J Howe
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
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59
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Corbeski I, Dolinar K, Wienk H, Boelens R, van Ingen H. DNA repair factor APLF acts as a H2A-H2B histone chaperone through binding its DNA interaction surface. Nucleic Acids Res 2018; 46:7138-7152. [PMID: 29905837 PMCID: PMC6101569 DOI: 10.1093/nar/gky507] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2017] [Revised: 05/02/2018] [Accepted: 05/22/2018] [Indexed: 01/23/2023] Open
Abstract
Genome replication, transcription and repair require the assembly/disassembly of the nucleosome. Histone chaperones are regulators of this process by preventing formation of non-nucleosomal histone-DNA complexes. Aprataxin and polynucleotide kinase like factor (APLF) is a non-homologous end-joining (NHEJ) DNA repair factor that possesses histone chaperone activity in its acidic domain (APLFAD). Here, we studied the molecular basis of this activity using biochemical and structural methods. We find that APLFAD is intrinsically disordered and binds histone complexes (H3-H4)2 and H2A-H2B specifically and with high affinity. APLFAD prevents unspecific complex formation between H2A-H2B and DNA in a chaperone assay, establishing for the first time its specific histone chaperone function for H2A-H2B. On the basis of a series of nuclear magnetic resonance studies, supported by mutational analysis, we show that the APLFAD histone binding domain uses two aromatic side chains to anchor to the α1-α2 patches on both H2A and H2B, thereby covering most of their DNA-interaction surface. An additional binding site on both APLFAD and H2A-H2B may be involved in the handoff between APLF and DNA or other chaperones. Together, our data support the view that APLF provides not only a scaffold but also generic histone chaperone activity for the NHEJ-complex.
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Affiliation(s)
- Ivan Corbeski
- NMR Spectroscopy, Bijvoet Center for Biomolecular Research, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands
| | - Klemen Dolinar
- NMR Spectroscopy, Bijvoet Center for Biomolecular Research, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands
- Group for Nano- and Biotechnological applications, Department of Fundamentals of Electrical Engineering, Mathematics and Physics, University of Ljubljana, Tržaška cesta 25, 1000 Ljubljana, Slovenia
| | - Hans Wienk
- NMR Spectroscopy, Bijvoet Center for Biomolecular Research, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands
| | - Rolf Boelens
- NMR Spectroscopy, Bijvoet Center for Biomolecular Research, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands
| | - Hugo van Ingen
- NMR Spectroscopy, Bijvoet Center for Biomolecular Research, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands
- Macromolecular Biochemistry, Leiden Institute of Chemistry, Leiden University, Einsteinweg 55, 2333 CC, Leiden, The Netherlands
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60
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Gurova K, Chang HW, Valieva ME, Sandlesh P, Studitsky VM. Structure and function of the histone chaperone FACT - Resolving FACTual issues. BIOCHIMICA ET BIOPHYSICA ACTA. GENE REGULATORY MECHANISMS 2018; 1861:S1874-9399(18)30159-7. [PMID: 30055319 PMCID: PMC6349528 DOI: 10.1016/j.bbagrm.2018.07.008] [Citation(s) in RCA: 70] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Revised: 07/17/2018] [Accepted: 07/19/2018] [Indexed: 12/12/2022]
Abstract
FAcilitates Chromatin Transcription (FACT) has been considered essential for transcription through chromatin mostly based on cell-free experiments. However, FACT inactivation in cells does not cause a significant reduction in transcription. Moreover, not all mammalian cells require FACT for viability. Here we synthesize information from different organisms to reveal the core function(s) of FACT and propose a model that reconciles the cell-free and cell-based observations. We describe FACT structure and nucleosomal interactions, and their roles in FACT-dependent transcription, replication and repair. The variable requirements for FACT among different tumor and non-tumor cells suggest that various FACT-dependent processes have significantly different levels of relative importance in different eukaryotic cells. We propose that the stability of chromatin, which might vary among different cell types, dictates these diverse requirements for FACT to support cell viability. Since tumor cells are among the most sensitive to FACT inhibition, this vulnerability could be exploited for cancer treatment.
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Affiliation(s)
- Katerina Gurova
- Department of Cell Stress Biology, Roswell Park Cancer Institute, Elm and Carlton Streets, Buffalo, NY 14263, USA.
| | - Han-Wen Chang
- Fox Chase Cancer Center, Philadelphia, PA 19111, USA
| | - Maria E Valieva
- Biology Faculty, Lomonosov Moscow State University, Moscow, Russia
| | - Poorva Sandlesh
- Department of Cell Stress Biology, Roswell Park Cancer Institute, Elm and Carlton Streets, Buffalo, NY 14263, USA
| | - Vasily M Studitsky
- Fox Chase Cancer Center, Philadelphia, PA 19111, USA; Biology Faculty, Lomonosov Moscow State University, Moscow, Russia.
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61
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Pfab A, Grønlund JT, Holzinger P, Längst G, Grasser KD. The Arabidopsis Histone Chaperone FACT: Role of the HMG-Box Domain of SSRP1. J Mol Biol 2018; 430:2747-2759. [PMID: 29966609 DOI: 10.1016/j.jmb.2018.06.046] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Revised: 06/18/2018] [Accepted: 06/22/2018] [Indexed: 11/15/2022]
Abstract
Histone chaperones play critical roles in regulated structural transitions of chromatin in eukaryotic cells that involve nucleosome disassembly and reassembly. The histone chaperone FACT is a heterodimeric complex consisting in plants and metazoa of SSRP1/SPT16 and is involved in dynamic nucleosome reorganization during various DNA-dependent processes including transcription, replication and repair. The C-terminal HMG-box domain of the SSRP1 subunit mediates interactions with DNA and nucleosomes in vitro, but its relevance in vivo is unclear. Here, we demonstrate that Arabidopsis ssrp1-2 mutant plants express a C-terminally truncated SSRP1 protein. Although the structure of the truncated HMG-box domain is distinctly disturbed, it still exhibits residual DNA-binding activity, but has lost DNA-bending activity. Since ssrp1-2 plants are phenotypically affected but viable, the HMG-box domain may be functionally non-essential. To examine this possibility, SSRP1∆HMG completely lacking the HMG-box domain was studied. SSRP1∆HMG in vitro did not bind to DNA and its interactions with nucleosomes were severely reduced. Nevertheless, the protein showed a nuclear mobility and protein interactions similar to SSRP1. Interestingly, expression of SSRP1∆HMG is almost as efficient as that of full-length SSRP1 in supporting normal growth and development of the otherwise non-viable Arabidopsis ssrp1-1 mutant. SSRP1∆HMG is structurally similar to the fungal ortholog termed Pob3 that shares clear similarity with SSRP1, but it lacks the C-terminal HMG-box. Therefore, our findings indicate that the HMG-box domain conserved among SSRP1 proteins is not critical in Arabidopsis, and thus, the functionality of SSRP1/SPT16 in plants/metazoa and Pob3/Spt16 in fungi is perhaps more similar than anticipated.
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Affiliation(s)
- Alexander Pfab
- Department of Cell Biology & Plant Biochemistry, Biochemistry Centre, University of Regensburg, Universitätsstr. 31, D-93053 Regensburg, Germany
| | - Jesper T Grønlund
- Department of Life Sciences, Aalborg University, Sohngaardsholmsvej 49, DK-9000 Aalborg, Denmark
| | - Philipp Holzinger
- Department of Cell Biology & Plant Biochemistry, Biochemistry Centre, University of Regensburg, Universitätsstr. 31, D-93053 Regensburg, Germany
| | - Gernot Längst
- Department of Biochemistry III, Biochemistry Centre, University of Regensburg, Universitätsstr. 31, D-93053 Regensburg, Germany
| | - Klaus D Grasser
- Department of Cell Biology & Plant Biochemistry, Biochemistry Centre, University of Regensburg, Universitätsstr. 31, D-93053 Regensburg, Germany.
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62
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Marcianò G, Da Vela S, Tria G, Svergun DI, Byron O, Huang DT. Structure-specific recognition protein-1 (SSRP1) is an elongated homodimer that binds histones. J Biol Chem 2018; 293:10071-10083. [PMID: 29764934 PMCID: PMC6028955 DOI: 10.1074/jbc.ra117.000994] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2017] [Revised: 05/14/2018] [Indexed: 12/31/2022] Open
Abstract
The histone chaperone complex facilitates chromatin transcription (FACT) plays important roles in DNA repair, replication, and transcription. In the formation of this complex, structure-specific recognition protein-1 (SSRP1) heterodimerizes with suppressor of Ty 16 (SPT16). SSRP1 also has SPT16-independent functions, but how SSRP1 functions alone remains elusive. Here, using analytical ultracentrifugation (AUC) and small-angle X-ray scattering (SAXS) techniques, we characterized human SSRP1 and that from the amoeba Dictyostelium discoideum and show that both orthologs form an elongated homodimer in solution. We found that substitutions in the SSRP1 pleckstrin homology domain known to bind SPT16 also disrupt SSRP1 homodimerization. Moreover, AUC and SAXS analyses revealed that SSRP1 homodimerization and heterodimerization with SPT16 (resulting in FACT) involve the same SSRP1 surface, namely the PH2 region, and that the FACT complex contains only one molecule of SSRP1. These observations suggest that SSRP1 homo- and heterodimerization might be mutually exclusive. Moreover, isothermal titration calorimetry analyses disclosed that SSRP1 binds both histones H2A-H2B and H3-H4 and that disruption of SSRP1 homodimerization decreases its histone-binding affinity. Together, our results provide evidence for regulation of SSRP1 by homodimerization and suggest a potential role for homodimerization in facilitating SPT16-independent functions of SSRP1.
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Affiliation(s)
- Gabriele Marcianò
- From the Cancer Research UK Beatson Institute, Garscube Estate, Switchback Road, and the Institute of Cancer Sciences, University of Glasgow, Glasgow G61 1BD, Scotland, United Kingdom,
| | - Stefano Da Vela
- the European Molecular Biology Laboratory, Hamburg Outstation, EMBL ℅ DESY, Notkestrasse 85, 22607 Hamburg, Germany, and
| | - Giancarlo Tria
- the European Molecular Biology Laboratory, Hamburg Outstation, EMBL ℅ DESY, Notkestrasse 85, 22607 Hamburg, Germany, and
| | - Dmitri I Svergun
- the European Molecular Biology Laboratory, Hamburg Outstation, EMBL ℅ DESY, Notkestrasse 85, 22607 Hamburg, Germany, and
| | - Olwyn Byron
- the School of Life Sciences, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - Danny T Huang
- From the Cancer Research UK Beatson Institute, Garscube Estate, Switchback Road, and the Institute of Cancer Sciences, University of Glasgow, Glasgow G61 1BD, Scotland, United Kingdom,
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63
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Mylonas C, Tessarz P. Transcriptional repression by FACT is linked to regulation of chromatin accessibility at the promoter of ES cells. Life Sci Alliance 2018; 1:e201800085. [PMID: 30456357 PMCID: PMC6238418 DOI: 10.26508/lsa.201800085] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Revised: 05/29/2018] [Accepted: 05/29/2018] [Indexed: 12/22/2022] Open
Abstract
Depletion of FACT in murine embryonic stem cells show mild changes on the nucleosomal landscape but widespread changes in the transcriptome, faster proliferation, and neuronal differentiation rates. The conserved and essential histone chaperone, facilitates chromatin transcription (FACT), reorganizes nucleosomes during DNA transcription, replication, and repair and ensures both efficient elongation of RNA Pol II and nucleosome integrity. In mammalian cells, FACT is a heterodimer, consisting of SSRP1 and SUPT16. Here, we show that in contrast to yeast, FACT accumulates at the transcription start site of genes reminiscent of RNA polymerase II profile. Depletion of FACT in mouse embryonic stem cells leads to deregulation of developmental and pro-proliferative genes concomitant with hyper-proliferation of mES cells. Using MNase-seq, Assay for Transposase-Accessible Chromatin sequencing, and nascent elongating transcript sequencing, we show that up-regulation of genes coincides with loss of nucleosomes upstream of the transcription start site and concomitant increase in antisense transcription, indicating that FACT impacts the promoter architecture to regulate the expression of these genes. Finally, we demonstrate a role for FACT in cell fate determination and show that FACT depletion primes embryonic stem cells for the neuronal lineage.
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Affiliation(s)
| | - Peter Tessarz
- Max Planck Institute for Biology of Ageing, Cologne, Germany.,Cologne Excellence Cluster on Cellular Stress Responses in Ageing Associated Diseases, University of Cologne, Cologne, Germany
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64
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Hamilton PD, Andley UP. In vitro interactions of histones and α-crystallin. Biochem Biophys Rep 2018; 15:7-12. [PMID: 30023439 PMCID: PMC6047474 DOI: 10.1016/j.bbrep.2018.05.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2018] [Revised: 05/15/2018] [Accepted: 05/17/2018] [Indexed: 11/15/2022] Open
Abstract
The aggregation of crystallins in lenses is associated with cataract formation. We previously reported that mutant crystallins are associated with an increased abundance of histones in knock-in and knockout mouse models. However, very little is known about the specific interactions between lens crystallins and histones. Here, we performed in vitro analyses to determine whether α-crystallin interacts with histones directly. Isothermal titration calorimetry revealed a strong histone–α-crystallin binding with a Kd of 4 × 10−7 M, and the thermodynamic parameters suggested that the interaction was both entropy and enthalpy driven. Size-exclusion chromatography further showed that histone–α-crystallin complexes are water soluble but become water insoluble as the concentration of histones is increased. Right-angle light scattering measurements of the water-soluble fractions of histone–α-crystallin mixtures showed a decrease in the oligomeric molecular weight of α-crystallin, indicating that histones alter the oligomerization of α-crystallin. Taken together, these findings reveal for the first time that histones interact with and affect the solubility and aggregation of α-crystallin, indicating that the interaction between α-crystallin and histones in the lens is functionally important. Histones are upregulated in α-crystallin mutant mice with hereditary cataracts. Isothermal titration calorimetry reveals histones and α-crystallin interact. These interactions are enthalpy and entropy driven. Histones affect the solubility and aggregation behavior of α-crystallin in vitro.
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Affiliation(s)
- Paul D Hamilton
- Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, MO, USA
| | - Usha P Andley
- Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, MO, USA
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65
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Acetylation-Dependent Recruitment of the FACT Complex and Its Role in Regulating Pol II Occupancy Genome-Wide in Saccharomyces cerevisiae. Genetics 2018; 209:743-756. [PMID: 29695490 DOI: 10.1534/genetics.118.300943] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Accepted: 04/23/2018] [Indexed: 12/23/2022] Open
Abstract
Histone chaperones, chromatin remodelers, and histone modifying complexes play a critical role in alleviating the nucleosomal barrier for DNA-dependent processes. Here, we have examined the role of two highly conserved yeast (Saccharomyces cerevisiae) histone chaperones, facilitates chromatin transcription (FACT) and Spt6, in regulating transcription. We show that the H3 tail contributes to the recruitment of FACT to coding sequences in a manner dependent on acetylation. We found that deleting a H3 histone acetyltransferase Gcn5 or mutating lysines on the H3 tail impairs FACT recruitment at ADH1 and ARG1 genes. However, deleting the H4 tail or mutating the H4 lysines failed to dampen FACT occupancy in coding regions. Additionally, we show that FACT depletion reduces RNA polymerase II (Pol II) occupancy genome-wide. Spt6 depletion leads to a reduction in Pol II occupancy toward the 3'-end, in a manner dependent on the gene length. Severe transcription and histone-eviction defects were also observed in a strain that was impaired for Spt6 recruitment (spt6Δ202) and depleted of FACT. Importantly, the severity of the defect strongly correlated with wild-type Pol II occupancies at these genes, indicating critical roles for Spt6 and Spt16 in promoting high-level transcription. Collectively, our results show that both FACT and Spt6 are important for transcription globally and may participate during different stages of transcription.
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66
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McCullough LL, Connell Z, Xin H, Studitsky VM, Feofanov AV, Valieva ME, Formosa T. Functional roles of the DNA-binding HMGB domain in the histone chaperone FACT in nucleosome reorganization. J Biol Chem 2018. [PMID: 29514976 DOI: 10.1074/jbc.ra117.000199] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The essential histone chaperone FACT (facilitates chromatin transcription) promotes both nucleosome assembly and disassembly. FACT is a heterodimer of Spt16 with either SSRP1 or Pob3, differing primarily by the presence of a high-mobility group B (HMGB) DNA-binding domain furnished only by SSRP1. Yeast FACT lacks the intrinsic HMGB domain found in SSRP1-based homologs such as human FACT, but yeast FACT activity is supported by Nhp6, which is a freestanding, single HMGB-domain protein. The importance of histone binding by FACT domains has been established, but the roles of DNA-binding activity remain poorly understood. Here, we examined these roles by fusing single or multiple HMGB modules to Pob3 to mimic SSRP1 or to test the effects of extended DNA-binding capacity. Human FACT and a yeast mimic both required Nhp6 to support nucleosome reorganization in vitro, indicating that a single intrinsic DNA-binding HMGB module is insufficient for full FACT activity. Three fused HMGB modules supported activity without Nhp6 assistance, but this FACT variant did not efficiently release from nucleosomes and was toxic in vivo Notably, intrinsic DNA-binding HMGB modules reduced the DNA accessibility and histone H2A-H2B dimer loss normally associated with nucleosome reorganization. We propose that DNA bending by HMGB domains promotes nucleosome destabilization and reorganization by exposing FACT's histone-binding sites, but DNA bending also produces DNA curvature needed to accommodate nucleosome assembly. Intrinsic DNA-bending activity therefore favors nucleosome assembly by FACT over nucleosome reorganization, but excessive activity impairs FACT release, suggesting a quality control checkpoint during nucleosome assembly.
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Affiliation(s)
- Laura L McCullough
- From the Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, Utah 84132
| | - Zaily Connell
- From the Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, Utah 84132
| | - Hua Xin
- From the Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, Utah 84132
| | - Vasily M Studitsky
- the Biology Faculty, Lomonosov, Moscow State University, Leninskie Gory 1, Moscow 119992, Russia.,the Fox Chase Cancer Center, Philadelphia, Pennsylvania 19111
| | - Alexey V Feofanov
- the Biology Faculty, Lomonosov, Moscow State University, Leninskie Gory 1, Moscow 119992, Russia.,the Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow 117997, Russia, and
| | - Maria E Valieva
- the Biology Faculty, Lomonosov, Moscow State University, Leninskie Gory 1, Moscow 119992, Russia
| | - Tim Formosa
- From the Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, Utah 84132,
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67
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Serra-Cardona A, Zhang Z. Replication-Coupled Nucleosome Assembly in the Passage of Epigenetic Information and Cell Identity. Trends Biochem Sci 2017; 43:136-148. [PMID: 29292063 DOI: 10.1016/j.tibs.2017.12.003] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2017] [Revised: 12/07/2017] [Accepted: 12/09/2017] [Indexed: 12/31/2022]
Abstract
During S phase, replicated DNA must be assembled into nucleosomes using both newly synthesized and parental histones in a process that is tightly coupled to DNA replication. This DNA replication-coupled process is regulated by multitude of histone chaperones as well as by histone-modifying enzymes. In recent years novel insights into nucleosome assembly of new H3-H4 tetramers have been gained through studies on the classical histone chaperone CAF-1 and the identification of novel factors involved in this process. Moreover, in vitro reconstitution of chromatin replication has shed light on nucleosome assembly of parental H3-H4, a process that remains elusive. Finally, recent studies have revealed that the replication-coupled nucleosome assembly is important for the determination and maintenance of cell fate in multicellular organisms.
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Affiliation(s)
- Albert Serra-Cardona
- Institute for Cancer Genetics, Columbia University, New York, NY 10032, USA; Department of Pediatrics, Columbia University, New York, NY 10032, USA; Department of Genetics and Development, Columbia University, New York, NY 10032, USA
| | - Zhiguo Zhang
- Institute for Cancer Genetics, Columbia University, New York, NY 10032, USA; Department of Pediatrics, Columbia University, New York, NY 10032, USA; Department of Genetics and Development, Columbia University, New York, NY 10032, USA.
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68
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Nyamugenda E, Cox AB, Pierce JB, Banning RC, Huynh ML, May C, Marshall S, Turkal CE, Duina AA. Charged residues on the side of the nucleosome contribute to normal Spt16-gene interactions in budding yeast. Epigenetics 2017; 13:1-7. [PMID: 29271283 DOI: 10.1080/15592294.2017.1418132] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
Abstract
Previous work in Saccharomyces cerevisiae identified three residues located in close proximity to each other on the side of the nucleosome whose integrity is required for proper association of the Spt16 component of the FACT complex across transcribed genes. In an effort to gain further insights into the parameters that control Spt16 interactions with genes in vivo, we tested the effects of additional histone mutants on Spt16 occupancy across two constitutively transcribed genes. These studies revealed that mutations in several charged residues in the vicinity of the three residues originally identified as important for Spt16-gene interactions also significantly perturb normal association of Spt16 across genes. Based on these and our previous findings, we propose that the charge landscape across the region encompassed by these residues, which we refer to as the Influences Spt16-Gene Interactions or ISGI region, is an important contributor to proper Spt16-gene interactions in vivo.
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Affiliation(s)
| | - A Brandon Cox
- a Biology Department , Hendrix College , Conway , AR 72032
| | - Jacob B Pierce
- a Biology Department , Hendrix College , Conway , AR 72032
| | - Ryan C Banning
- a Biology Department , Hendrix College , Conway , AR 72032
| | | | - Catey May
- a Biology Department , Hendrix College , Conway , AR 72032
| | - Sarah Marshall
- a Biology Department , Hendrix College , Conway , AR 72032
| | | | - Andrea A Duina
- a Biology Department , Hendrix College , Conway , AR 72032
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69
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Miller TC, Costa A. The architecture and function of the chromatin replication machinery. Curr Opin Struct Biol 2017; 47:9-16. [PMID: 28419835 DOI: 10.1016/j.sbi.2017.03.011] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2017] [Accepted: 03/20/2017] [Indexed: 12/11/2022]
Abstract
Genomic DNA in eukaryotic cells is packaged into nucleosome arrays. During replication, nucleosomes need to be dismantled ahead of the advancing replication fork and reassembled on duplicated DNA. The architecture and function of the core replisome machinery is now beginning to be elucidated, with recent insights shaping our view on DNA replication processes. Simultaneously, breakthroughs in our mechanistic understanding of epigenetic inheritance allow us to build new models of how histone chaperones integrate with the replisome to reshuffle nucleosomes. The emerging picture indicates that the core eukaryotic DNA replication machinery has evolved elements that handle nucleosomes to facilitate chromatin duplication.
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Affiliation(s)
- Thomas Cr Miller
- Molecular Machines Laboratory, The Francis Crick Institute, 1 Midland Rd, NW11AT London, United Kingdom
| | - Alessandro Costa
- Molecular Machines Laboratory, The Francis Crick Institute, 1 Midland Rd, NW11AT London, United Kingdom.
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70
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Chen P, Li G. Structure and Epigenetic Regulation of Chromatin Fibers. COLD SPRING HARBOR SYMPOSIA ON QUANTITATIVE BIOLOGY 2017; 82:25-35. [PMID: 29167282 DOI: 10.1101/sqb.2017.82.033795] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
In eukaryotes, genomic DNA is hierarchically packaged by histones into chromatin on several levels to fit inside the nucleus. As a central-level structure between nucleosomal arrays and higher-order chromatin organizations, the 30-nm chromatin fiber and its dynamics play a crucial role in gene regulation. However, despite considerable efforts over the past three decades, the fundamental structure and its dynamic regulation of chromatin fibers still remain as a big challenge in molecular biology. Here, we mainly summarize the most recent progress in elucidating the structure of the 30-nm chromatin fiber in vitro and epigenetic regulation of chromatin fibers by chromatin factors, particularly histone variants. In addition, we also discuss recent studies in unraveling the three-dimensional organization of chromatin fibers in situ by genomic approaches and electron microscopy.
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Affiliation(s)
- Ping Chen
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Guohong Li
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
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71
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Shintomi K, Hirano T. Mitotic Chromosome Assembly In Vitro: Functional Cross Talk between Nucleosomes and Condensins. COLD SPRING HARBOR SYMPOSIA ON QUANTITATIVE BIOLOGY 2017; 82:157-164. [PMID: 29118204 DOI: 10.1101/sqb.2017.82.033639] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The mitotic chromosome is a macromolecular assembly that ensures error-free transmission of the genome during cell division. It has long been a big mystery how long stretches of DNA might be folded into rod-shaped chromosomes or how such an elaborate process might be accomplished at a mechanistic level. Cell-free extracts made from frog eggs offer a unique opportunity to address these questions by enabling mitotic chromosomes to be assembled in a test tube. Moreover, the core part of the chromosome assembly reaction can now be reconstituted with a limited number of purified factors. A combination of these in vitro assays makes it possible not only to prepare a complete list of proteins required for chromosome assembly but also to dissect functions of individual proteins and their cooperation with unparalleled clarity. Emerging lines of evidence underscore the paramount importance of condensins in building mitotic chromosomes and shed new light on the functional cross talk between nucleosomes and condensins in this process.
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Affiliation(s)
- Keishi Shintomi
- Chromosome Dynamics Laboratory, RIKEN, Wako, Saitama 351-0198, Japan
| | - Tatsuya Hirano
- Chromosome Dynamics Laboratory, RIKEN, Wako, Saitama 351-0198, Japan
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72
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Safina A, Cheney P, Pal M, Brodsky L, Ivanov A, Kirsanov K, Lesovaya E, Naberezhnov D, Nesher E, Koman I, Wang D, Wang J, Yakubovskaya M, Winkler D, Gurova K. FACT is a sensor of DNA torsional stress in eukaryotic cells. Nucleic Acids Res 2017; 45:1925-1945. [PMID: 28082391 PMCID: PMC5389579 DOI: 10.1093/nar/gkw1366] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2016] [Accepted: 12/29/2016] [Indexed: 02/01/2023] Open
Abstract
Transitions of B-DNA to alternative DNA structures (ADS) can be triggered by negative torsional strain, which occurs during replication and transcription, and may lead to genomic instability. However, how ADS are recognized in cells is unclear. We found that the binding of candidate anticancer drug, curaxin, to cellular DNA results in uncoiling of nucleosomal DNA, accumulation of negative supercoiling and conversion of multiple regions of genomic DNA into left-handed Z-form. Histone chaperone FACT binds rapidly to the same regions via the SSRP1 subunit in curaxin-treated cells. In vitro binding of purified SSRP1 or its isolated CID domain to a methylated DNA fragment containing alternating purine/pyrimidines, which is prone to Z-DNA transition, is much stronger than to other types of DNA. We propose that FACT can recognize and bind Z-DNA or DNA in transition from a B to Z form. Binding of FACT to these genomic regions triggers a p53 response. Furthermore, FACT has been shown to bind to other types of ADS through a different structural domain, which also leads to p53 activation. Thus, we propose that FACT acts as a sensor of ADS formation in cells. Recognition of ADS by FACT followed by a p53 response may explain the role of FACT in DNA damage prevention.
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Affiliation(s)
- Alfiya Safina
- Department of Cell Stress Biology, Roswell Park Cancer Institute, Elm and Carlton Streets, Buffalo, NY 14127, USA
| | - Peter Cheney
- Department of Cell Stress Biology, Roswell Park Cancer Institute, Elm and Carlton Streets, Buffalo, NY 14127, USA
| | - Mahadeb Pal
- Department of Cell Stress Biology, Roswell Park Cancer Institute, Elm and Carlton Streets, Buffalo, NY 14127, USA
| | - Leonid Brodsky
- Department of Evolutionary & Environmental Biology, Tauber Bioinformatics Research Center, University of Haifa, Mount Carmel, Haifa 31905, Israel
| | - Alexander Ivanov
- Department of Chemical Carcinogenesis, Institute of Carcinogenesis, Blokhin Cancer Research Center RAMS, Moscow 115478, Russia
| | - Kirill Kirsanov
- Department of Chemical Carcinogenesis, Institute of Carcinogenesis, Blokhin Cancer Research Center RAMS, Moscow 115478, Russia
| | - Ekaterina Lesovaya
- Department of Chemical Carcinogenesis, Institute of Carcinogenesis, Blokhin Cancer Research Center RAMS, Moscow 115478, Russia.,I.P. Pavlov Ryazan State Medical University, Ryazan, Russia
| | - Denis Naberezhnov
- Department of Chemical Carcinogenesis, Institute of Carcinogenesis, Blokhin Cancer Research Center RAMS, Moscow 115478, Russia
| | - Elimelech Nesher
- Department of Cell Stress Biology, Roswell Park Cancer Institute, Elm and Carlton Streets, Buffalo, NY 14127, USA.,Department of Molecular Biology, Ariel University, Ariel 40700, Israel
| | - Igor Koman
- Department of Molecular Biology, Ariel University, Ariel 40700, Israel
| | - Dan Wang
- Department of Bioinformatics, Roswell Park Cancer Institute, Elm and Carlton Streets, Buffalo, NY 14127, USA
| | - Jianming Wang
- Department of Bioinformatics, Roswell Park Cancer Institute, Elm and Carlton Streets, Buffalo, NY 14127, USA
| | - Marianna Yakubovskaya
- Department of Chemical Carcinogenesis, Institute of Carcinogenesis, Blokhin Cancer Research Center RAMS, Moscow 115478, Russia
| | - Duane Winkler
- Department of Molecular and Cell Biology, University of Texas at Dallas, 800 W. Campbell Rd., Richardson, TX 75080, USA
| | - Katerina Gurova
- Department of Cell Stress Biology, Roswell Park Cancer Institute, Elm and Carlton Streets, Buffalo, NY 14127, USA
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73
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Kevei É, Pokrzywa W, Hoppe T. Repair or destruction-an intimate liaison between ubiquitin ligases and molecular chaperones in proteostasis. FEBS Lett 2017; 591:2616-2635. [PMID: 28699655 PMCID: PMC5601288 DOI: 10.1002/1873-3468.12750] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Revised: 07/04/2017] [Accepted: 07/06/2017] [Indexed: 12/11/2022]
Abstract
Cellular differentiation, developmental processes, and environmental factors challenge the integrity of the proteome in every eukaryotic cell. The maintenance of protein homeostasis, or proteostasis, involves folding and degradation of damaged proteins, and is essential for cellular function, organismal growth, and viability 1, 2. Misfolded proteins that cannot be refolded by chaperone machineries are degraded by specialized proteolytic systems. A major degradation pathway regulating cellular proteostasis is the ubiquitin (Ub)/proteasome system (UPS), which regulates turnover of damaged proteins that accumulate upon stress and during aging. Despite a large number of structurally unrelated substrates, Ub conjugation is remarkably selective. Substrate selectivity is mainly provided by the group of E3 enzymes. Several observations indicate that numerous E3 Ub ligases intimately collaborate with molecular chaperones to maintain the cellular proteome. In this review, we provide an overview of specialized quality control E3 ligases playing a critical role in the degradation of damaged proteins. The process of substrate recognition and turnover, the type of chaperones they team up with, and the potential pathogeneses associated with their malfunction will be further discussed.
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Affiliation(s)
- Éva Kevei
- School of Biological Sciences, University of Reading, Whiteknights, UK
| | - Wojciech Pokrzywa
- International Institute of Molecular and Cell Biology in Warsaw, Poland
| | - Thorsten Hoppe
- Institute for Genetics and Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Germany
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74
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Rowlands H, Dhavarasa P, Cheng A, Yankulov K. Forks on the Run: Can the Stalling of DNA Replication Promote Epigenetic Changes? Front Genet 2017; 8:86. [PMID: 28690636 PMCID: PMC5479891 DOI: 10.3389/fgene.2017.00086] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2017] [Accepted: 06/06/2017] [Indexed: 11/13/2022] Open
Abstract
Built of DNA polymerases and multiple associated factors, the replication fork steadily progresses along the DNA template and faithfully replicates DNA. This model can be found in practically every textbook of genetics, with the more complex situation of chromatinized DNA in eukaryotes often viewed as a variation. However, the replication-coupled disassembly/reassembly of chromatin adds significant complexity to the whole replication process. During the course of eukaryotic DNA replication the forks encounter various conditions and numerous impediments. These include nucleosomes with a variety of post-translational modifications, euchromatin and heterochromatin, differentially methylated DNA, tightly bound proteins, active gene promoters and DNA loops. At such positions the forks slow down or even stall. Dedicated factors stabilize the fork and prevent its rotation or collapse, while other factors resolve the replication block and facilitate the resumption of elongation. The fate of histones during replication stalling and resumption is not well understood. In this review we briefly describe recent advances in our understanding of histone turnover during DNA replication and focus on the possible mechanisms of nucleosome disassembly/reassembly at paused replication forks. We propose that replication pausing provides opportunities for an epigenetic change of the associated locus.
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Affiliation(s)
- Hollie Rowlands
- Department of Molecular and Cellular Biology, University of Guelph, GuelphON, Canada
| | - Piriththiv Dhavarasa
- Department of Molecular and Cellular Biology, University of Guelph, GuelphON, Canada
| | - Ashley Cheng
- Department of Molecular and Cellular Biology, University of Guelph, GuelphON, Canada
| | - Krassimir Yankulov
- Department of Molecular and Cellular Biology, University of Guelph, GuelphON, Canada
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75
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Warren C, Shechter D. Fly Fishing for Histones: Catch and Release by Histone Chaperone Intrinsically Disordered Regions and Acidic Stretches. J Mol Biol 2017; 429:2401-2426. [PMID: 28610839 DOI: 10.1016/j.jmb.2017.06.005] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2017] [Revised: 06/05/2017] [Accepted: 06/06/2017] [Indexed: 01/21/2023]
Abstract
Chromatin is the complex of eukaryotic DNA and proteins required for the efficient compaction of the nearly 2-meter-long human genome into a roughly 10-micron-diameter cell nucleus. The fundamental repeating unit of chromatin is the nucleosome: 147bp of DNA wrapped about an octamer of histone proteins. Nucleosomes are stable enough to organize the genome yet must be dynamically displaced and reassembled to allow access to the underlying DNA for transcription, replication, and DNA damage repair. Histone chaperones are a non-catalytic group of proteins that are central to the processes of nucleosome assembly and disassembly and thus the fluidity of the ever-changing chromatin landscape. Histone chaperones are responsible for binding the highly basic histone proteins, shielding them from non-specific interactions, facilitating their deposition onto DNA, and aiding in their eviction from DNA. Although most histone chaperones perform these common functions, recent structural studies of many different histone chaperones reveal that there are few commonalities in their folds. Importantly, sequence-based predictions show that histone chaperones are highly enriched in intrinsically disordered regions (IDRs) and acidic stretches. In this review, we focus on the molecular mechanisms underpinning histone binding, selectivity, and regulation of these highly dynamic protein regions. We highlight new evidence suggesting that IDRs are often critical for histone chaperone function and play key roles in chromatin assembly and disassembly pathways.
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Affiliation(s)
- Christopher Warren
- Department of Biochemistry, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY 10461, USA
| | - David Shechter
- Department of Biochemistry, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY 10461, USA.
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76
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Chen CC, Mellone BG. Chromatin assembly: Journey to the CENter of the chromosome. J Cell Biol 2017; 214:13-24. [PMID: 27377247 PMCID: PMC4932374 DOI: 10.1083/jcb.201605005] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2016] [Accepted: 06/14/2016] [Indexed: 11/22/2022] Open
Abstract
All eukaryotic genomes are packaged into basic units of DNA wrapped around histone proteins called nucleosomes. The ability of histones to specify a variety of epigenetic states at defined chromatin domains is essential for cell survival. The most distinctive type of chromatin is found at centromeres, which are marked by the centromere-specific histone H3 variant CENP-A. Many of the factors that regulate CENP-A chromatin have been identified; however, our understanding of the mechanisms of centromeric nucleosome assembly, maintenance, and reorganization remains limited. This review discusses recent insights into these processes and draws parallels between centromeric and noncentromeric chromatin assembly mechanisms.
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Affiliation(s)
- Chin-Chi Chen
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT 06269
| | - Barbara G Mellone
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT 06269 Institute for Systems Genomics, University of Connecticut, Storrs, CT 06269
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77
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Understanding nucleosome dynamics and their links to gene expression and DNA replication. Nat Rev Mol Cell Biol 2017; 18:548-562. [PMID: 28537572 DOI: 10.1038/nrm.2017.47] [Citation(s) in RCA: 309] [Impact Index Per Article: 44.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Advances in genomics technology have provided the means to probe myriad chromatin interactions at unprecedented spatial and temporal resolution. This has led to a profound understanding of nucleosome organization within the genome, revealing that nucleosomes are highly dynamic. Nucleosome dynamics are governed by a complex interplay of histone composition, histone post-translational modifications, nucleosome occupancy and positioning within chromatin, which are influenced by numerous regulatory factors, including general regulatory factors, chromatin remodellers, chaperones and polymerases. It is now known that these dynamics regulate diverse cellular processes ranging from gene transcription to DNA replication and repair.
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78
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Golloshi R, Sanders JT, McCord RP. Genome organization during the cell cycle: unity in division. WILEY INTERDISCIPLINARY REVIEWS-SYSTEMS BIOLOGY AND MEDICINE 2017; 9. [PMID: 28510289 DOI: 10.1002/wsbm.1389] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Revised: 03/12/2017] [Accepted: 03/14/2017] [Indexed: 12/11/2022]
Abstract
During the cell cycle, the genome must undergo dramatic changes in structure, from a decondensed, yet highly organized interphase structure to a condensed, generic mitotic chromosome and then back again. For faithful cell division, the genome must be replicated and chromosomes and sister chromatids physically segregated from one another. Throughout these processes, there is feedback and tension between the information-storing role and the physical properties of chromosomes. With a combination of recent techniques in fluorescence microscopy, chromosome conformation capture (Hi-C), biophysical experiments, and computational modeling, we can now attribute mechanisms to many long-observed features of chromosome structure changes during cell division. Apparent conflicts that arise when integrating the concepts from these different proposed mechanisms emphasize that orchestrating chromosome organization during cell division requires a complex system of factors rather than a simple pathway. Cell division is both essential for and threatening to proper genome organization. As interphase three-dimensional (3D) genome structure is quite static at a global level, cell division provides an important window of opportunity to make substantial changes in 3D genome organization in daughter cells, allowing for proper differentiation and development. Mistakes in the process of chromosome condensation or rebuilding the structure after mitosis can lead to diseases such as cancer, premature aging, and neurodegeneration. WIREs Syst Biol Med 2017, 9:e1389. doi: 10.1002/wsbm.1389 For further resources related to this article, please visit the WIREs website.
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Affiliation(s)
- Rosela Golloshi
- Department of Biochemistry & Cellular and Molecular Biology, University of Tennessee, Knoxville, TN, USA
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79
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Residues in the Nucleosome Acidic Patch Regulate Histone Occupancy and Are Important for FACT Binding in Saccharomyces cerevisiae. Genetics 2017; 206:1339-1348. [PMID: 28468903 DOI: 10.1534/genetics.117.201939] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2017] [Accepted: 04/22/2017] [Indexed: 01/02/2023] Open
Abstract
The essential histone chaperone FACT plays a critical role in DNA replication, repair, and transcription, primarily by binding to histone H2A-H2B dimers and regulating their assembly into nucleosomes. While FACT histone chaperone activity has been extensively studied, the exact nature of the H2A and H2B residues important for FACT binding remains controversial. In this study, we characterized the functions of residues in the histone H2A and H2B acidic patch, which is important for binding many chromatin-associated factors. We found that mutations in essential acidic patch residues cause a defect in histone occupancy in yeast, even though most of these histone mutants are expressed normally in yeast and form stable nucleosomes in vitro Instead, we show that two acidic patch residues, H2B L109 and H2A E57, are important for histone binding to FACT in vivo We systematically screened mutants in other H2A and H2B residues previously suspected to be important for FACT binding and confirmed the importance of H2B M62 using an in-vivo FACT-binding assay. Furthermore, we show that, like deletion mutants in FACT subunits, an H2A E57 and H2B M62 double mutant is lethal in yeast. In summary, we show that residues in the nucleosome acidic patch promote histone occupancy and are important for FACT binding to H2A-H2B dimers in yeast.
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80
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Mahé EA, Madigou T, Sérandour AA, Bizot M, Avner S, Chalmel F, Palierne G, Métivier R, Salbert G. Cytosine modifications modulate the chromatin architecture of transcriptional enhancers. Genome Res 2017; 27:947-958. [PMID: 28396520 PMCID: PMC5453328 DOI: 10.1101/gr.211466.116] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Accepted: 04/05/2017] [Indexed: 12/19/2022]
Abstract
Epigenetic mechanisms are believed to play key roles in the establishment of cell-specific transcription programs. Accordingly, the modified bases 5-methylcytosine (5mC) and 5-hydroxymethylcytosine (5hmC) have been observed in DNA of genomic regulatory regions such as enhancers, and oxidation of 5mC into 5hmC by Ten-eleven translocation (TET) proteins correlates with enhancer activation. However, the functional relationship between cytosine modifications and the chromatin architecture of enhancers remains elusive. To gain insights into their function, 5mC and 5hmC levels were perturbed by inhibiting DNA methyltransferases and TETs during differentiation of mouse embryonal carcinoma cells into neural progenitors, and chromatin characteristics of enhancers bound by the pioneer transcription factors FOXA1, MEIS1, and PBX1 were interrogated. In a large fraction of the tested enhancers, inhibition of DNA methylation was associated with a significant increase in monomethylation of H3K4, a characteristic mark of enhancer priming. In addition, at some specific enhancers, 5mC oxidation by TETs facilitated chromatin opening, a process that may stabilize MEIS1 binding to these genomic regions.
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Affiliation(s)
- Elise A Mahé
- CNRS UMR6290, Equipe SP@RTE, Institut de Génétique et Développement de Rennes, Campus de Beaulieu, 35042 Rennes Cedex, France.,Université de Rennes 1, Campus de Beaulieu, 35042 Rennes Cedex, France
| | - Thierry Madigou
- CNRS UMR6290, Equipe SP@RTE, Institut de Génétique et Développement de Rennes, Campus de Beaulieu, 35042 Rennes Cedex, France.,Université de Rennes 1, Campus de Beaulieu, 35042 Rennes Cedex, France
| | | | - Maud Bizot
- CNRS UMR6290, Equipe SP@RTE, Institut de Génétique et Développement de Rennes, Campus de Beaulieu, 35042 Rennes Cedex, France.,Université de Rennes 1, Campus de Beaulieu, 35042 Rennes Cedex, France
| | - Stéphane Avner
- CNRS UMR6290, Equipe SP@RTE, Institut de Génétique et Développement de Rennes, Campus de Beaulieu, 35042 Rennes Cedex, France.,Université de Rennes 1, Campus de Beaulieu, 35042 Rennes Cedex, France
| | - Frédéric Chalmel
- Inserm U1085-IRSET, Université de Rennes 1, F-35042 Rennes, France
| | - Gaëlle Palierne
- CNRS UMR6290, Equipe SP@RTE, Institut de Génétique et Développement de Rennes, Campus de Beaulieu, 35042 Rennes Cedex, France.,Université de Rennes 1, Campus de Beaulieu, 35042 Rennes Cedex, France
| | - Raphaël Métivier
- CNRS UMR6290, Equipe SP@RTE, Institut de Génétique et Développement de Rennes, Campus de Beaulieu, 35042 Rennes Cedex, France.,Université de Rennes 1, Campus de Beaulieu, 35042 Rennes Cedex, France
| | - Gilles Salbert
- CNRS UMR6290, Equipe SP@RTE, Institut de Génétique et Développement de Rennes, Campus de Beaulieu, 35042 Rennes Cedex, France.,Université de Rennes 1, Campus de Beaulieu, 35042 Rennes Cedex, France
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81
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Fischl H, Howe FS, Furger A, Mellor J. Paf1 Has Distinct Roles in Transcription Elongation and Differential Transcript Fate. Mol Cell 2017; 65:685-698.e8. [PMID: 28190769 PMCID: PMC5316414 DOI: 10.1016/j.molcel.2017.01.006] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Revised: 09/22/2016] [Accepted: 01/05/2017] [Indexed: 12/12/2022]
Abstract
RNA polymerase II (Pol2) movement through chromatin and the co-transcriptional processing and fate of nascent transcripts is coordinated by transcription elongation factors (TEFs) such as polymerase-associated factor 1 (Paf1), but it is not known whether TEFs have gene-specific functions. Using strand-specific nucleotide resolution techniques, we show that levels of Paf1 on Pol2 vary between genes, are controlled dynamically by environmental factors via promoters, and reflect levels of processing and export factors on the encoded transcript. High levels of Paf1 on Pol2 promote transcript nuclear export, whereas low levels reflect nuclear retention. Strains lacking Paf1 show marked elongation defects, although low levels of Paf1 on Pol2 are sufficient for transcription elongation. Our findings support distinct Paf1 functions: a core general function in transcription elongation, satisfied by the lowest Paf1 levels, and a regulatory function in determining differential transcript fate by varying the level of Paf1 on Pol2.
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Affiliation(s)
- Harry Fischl
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, UK
| | - Françoise S Howe
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, UK
| | - Andre Furger
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, UK
| | - Jane Mellor
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, UK.
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82
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Reddy BA, Jeronimo C, Robert F. Recent Perspectives on the Roles of Histone Chaperones in Transcription Regulation. ACTA ACUST UNITED AC 2017. [DOI: 10.1007/s40610-017-0049-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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83
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Baßler J, Ahmed YL, Kallas M, Kornprobst M, Calviño FR, Gnädig M, Thoms M, Stier G, Ismail S, Kharde S, Castillo N, Griesel S, Bastuck S, Bradatsch B, Thomson E, Flemming D, Sinning I, Hurt E. Interaction network of the ribosome assembly machinery from a eukaryotic thermophile. Protein Sci 2017; 26:327-342. [PMID: 27863450 DOI: 10.1002/pro.3085] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2016] [Revised: 10/24/2016] [Accepted: 11/08/2016] [Indexed: 12/30/2022]
Abstract
Ribosome biogenesis in eukaryotic cells is a highly dynamic and complex process innately linked to cell proliferation. The assembly of ribosomes is driven by a myriad of biogenesis factors that shape pre-ribosomal particles by processing and folding the ribosomal RNA and incorporating ribosomal proteins. Biochemical approaches allowed the isolation and characterization of pre-ribosomal particles from Saccharomyces cerevisiae, which lead to a spatiotemporal map of biogenesis intermediates along the path from the nucleolus to the cytoplasm. Here, we cloned almost the entire set (∼180) of ribosome biogenesis factors from the thermophilic fungus Chaetomium thermophilum in order to perform an in-depth analysis of their protein-protein interaction network as well as exploring the suitability of these thermostable proteins for structural studies. First, we performed a systematic screen, testing about 80 factors for crystallization and structure determination. Next, we performed a yeast 2-hybrid analysis and tested about 32,000 binary combinations, which identified more than 1000 protein-protein contacts between the thermophilic ribosome assembly factors. To exemplary verify several of these interactions, we performed biochemical reconstitution with the focus on the interaction network between 90S pre-ribosome factors forming the ctUTP-A and ctUTP-B modules, and the Brix-domain containing assembly factors of the pre-60S subunit. Our work provides a rich resource for biochemical reconstitution and structural analyses of the conserved ribosome assembly machinery from a eukaryotic thermophile.
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Affiliation(s)
- Jochen Baßler
- Biochemistry Center Heidelberg BZH, University of Heidelberg, Heidelberg, 69120, Germany
| | - Yasar Luqman Ahmed
- Biochemistry Center Heidelberg BZH, University of Heidelberg, Heidelberg, 69120, Germany
| | - Martina Kallas
- Biochemistry Center Heidelberg BZH, University of Heidelberg, Heidelberg, 69120, Germany
| | - Markus Kornprobst
- Biochemistry Center Heidelberg BZH, University of Heidelberg, Heidelberg, 69120, Germany
| | - Fabiola R Calviño
- Biochemistry Center Heidelberg BZH, University of Heidelberg, Heidelberg, 69120, Germany
| | - Marén Gnädig
- Biochemistry Center Heidelberg BZH, University of Heidelberg, Heidelberg, 69120, Germany
| | - Matthias Thoms
- Biochemistry Center Heidelberg BZH, University of Heidelberg, Heidelberg, 69120, Germany
| | - Gunter Stier
- Biochemistry Center Heidelberg BZH, University of Heidelberg, Heidelberg, 69120, Germany
| | - Sherif Ismail
- Biochemistry Center Heidelberg BZH, University of Heidelberg, Heidelberg, 69120, Germany
| | - Satyavati Kharde
- Biochemistry Center Heidelberg BZH, University of Heidelberg, Heidelberg, 69120, Germany
| | - Nestor Castillo
- Biochemistry Center Heidelberg BZH, University of Heidelberg, Heidelberg, 69120, Germany
| | - Sabine Griesel
- Biochemistry Center Heidelberg BZH, University of Heidelberg, Heidelberg, 69120, Germany
| | - Sonja Bastuck
- Biochemistry Center Heidelberg BZH, University of Heidelberg, Heidelberg, 69120, Germany
| | - Bettina Bradatsch
- Biochemistry Center Heidelberg BZH, University of Heidelberg, Heidelberg, 69120, Germany
| | - Emma Thomson
- Biochemistry Center Heidelberg BZH, University of Heidelberg, Heidelberg, 69120, Germany
| | - Dirk Flemming
- Biochemistry Center Heidelberg BZH, University of Heidelberg, Heidelberg, 69120, Germany
| | - Irmgard Sinning
- Biochemistry Center Heidelberg BZH, University of Heidelberg, Heidelberg, 69120, Germany
| | - Ed Hurt
- Biochemistry Center Heidelberg BZH, University of Heidelberg, Heidelberg, 69120, Germany
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84
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Valieva ME, Gerasimova NS, Kudryashova KS, Kozlova AL, Kirpichnikov MP, Hu Q, Botuyan MV, Mer G, Feofanov AV, Studitsky VM. Stabilization of Nucleosomes by Histone Tails and by FACT Revealed by spFRET Microscopy. Cancers (Basel) 2017; 9:cancers9010003. [PMID: 28067802 PMCID: PMC5295774 DOI: 10.3390/cancers9010003] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2016] [Revised: 12/19/2016] [Accepted: 12/22/2016] [Indexed: 12/31/2022] Open
Abstract
A correct chromatin structure is important for cell viability and is tightly regulated by numerous factors. Human protein complex FACT (facilitates chromatin transcription) is an essential factor involved in chromatin transcription and cancer development. Here FACT-dependent changes in the structure of single nucleosomes were studied with single-particle Förster resonance energy transfer (spFRET) microscopy using nucleosomes labeled with a donor-acceptor pair of fluorophores, which were attached to the adjacent gyres of DNA near the contact between H2A-H2B dimers. Human FACT and its version without the C-terminal domain (CTD) and the high mobility group (HMG) domain of the structure-specific recognition protein 1 (SSRP1) subunit did not change the structure of the nucleosomes, while FACT without the acidic C-terminal domains of the suppressor of Ty 16 (Spt16) and the SSRP1 subunits caused nucleosome aggregation. Proteolytic removal of histone tails significantly disturbed the nucleosome structure, inducing partial unwrapping of nucleosomal DNA. Human FACT reduced DNA unwrapping and stabilized the structure of tailless nucleosomes. CTD and/or HMG domains of SSRP1 are required for this FACT activity. In contrast, previously it has been shown that yeast FACT unfolds (reorganizes) nucleosomes using the CTD domain of SSRP1-like Pol I-binding protein 3 subunit (Pob3). Thus, yeast and human FACT complexes likely utilize the same domains for nucleosome reorganization and stabilization, respectively, and these processes are mechanistically similar.
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Affiliation(s)
- Maria E Valieva
- Biology Faculty, Lomonosov Moscow State University, Leninskie Gory 1, Moscow 119992, Russia.
| | - Nadezhda S Gerasimova
- Biology Faculty, Lomonosov Moscow State University, Leninskie Gory 1, Moscow 119992, Russia.
| | - Kseniya S Kudryashova
- Biology Faculty, Lomonosov Moscow State University, Leninskie Gory 1, Moscow 119992, Russia.
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry of Russian Academy of Sciences, Moscow 117997, Russia.
| | - Anastasia L Kozlova
- Biology Faculty, Lomonosov Moscow State University, Leninskie Gory 1, Moscow 119992, Russia.
| | - Mikhail P Kirpichnikov
- Biology Faculty, Lomonosov Moscow State University, Leninskie Gory 1, Moscow 119992, Russia.
| | - Qi Hu
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN 55905, USA.
| | - Maria Victoria Botuyan
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN 55905, USA.
| | - Georges Mer
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN 55905, USA.
| | - Alexey V Feofanov
- Biology Faculty, Lomonosov Moscow State University, Leninskie Gory 1, Moscow 119992, Russia.
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry of Russian Academy of Sciences, Moscow 117997, Russia.
| | - Vasily M Studitsky
- Biology Faculty, Lomonosov Moscow State University, Leninskie Gory 1, Moscow 119992, Russia.
- Fox Chase Cancer Center, Philadelphia, PA 19111, USA.
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85
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Hammond CM, Strømme CB, Huang H, Patel DJ, Groth A. Histone chaperone networks shaping chromatin function. Nat Rev Mol Cell Biol 2017; 18:141-158. [PMID: 28053344 DOI: 10.1038/nrm.2016.159] [Citation(s) in RCA: 347] [Impact Index Per Article: 49.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The association of histones with specific chaperone complexes is important for their folding, oligomerization, post-translational modification, nuclear import, stability, assembly and genomic localization. In this way, the chaperoning of soluble histones is a key determinant of histone availability and fate, which affects all chromosomal processes, including gene expression, chromosome segregation and genome replication and repair. Here, we review the distinct structural and functional properties of the expanding network of histone chaperones. We emphasize how chaperones cooperate in the histone chaperone network and via co-chaperone complexes to match histone supply with demand, thereby promoting proper nucleosome assembly and maintaining epigenetic information by recycling modified histones evicted from chromatin.
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Affiliation(s)
- Colin M Hammond
- Biotech Research and Innovation Centre (BRIC) and Centre for Epigenetics, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen DK-2200, Denmark
| | - Caroline B Strømme
- Biotech Research and Innovation Centre (BRIC) and Centre for Epigenetics, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen DK-2200, Denmark
| | - Hongda Huang
- Structural Biology Program, Memorial Sloan-Kettering Cancer Center, New York, New York 10065, USA
| | - Dinshaw J Patel
- Structural Biology Program, Memorial Sloan-Kettering Cancer Center, New York, New York 10065, USA
| | - Anja Groth
- Biotech Research and Innovation Centre (BRIC) and Centre for Epigenetics, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen DK-2200, Denmark
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86
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Alabert C, Jasencakova Z, Groth A. Chromatin Replication and Histone Dynamics. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 1042:311-333. [PMID: 29357065 DOI: 10.1007/978-981-10-6955-0_15] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Inheritance of the DNA sequence and its proper organization into chromatin is fundamental for genome stability and function. Therefore, how specific chromatin structures are restored on newly synthesized DNA and transmitted through cell division remains a central question to understand cell fate choices and self-renewal. Propagation of genetic information and chromatin-based information in cycling cells entails genome-wide disruption and restoration of chromatin, coupled with faithful replication of DNA. In this chapter, we describe how cells duplicate the genome while maintaining its proper organization into chromatin. We reveal how specialized replication-coupled mechanisms rapidly assemble newly synthesized DNA into nucleosomes, while the complete restoration of chromatin organization including histone marks is a continuous process taking place throughout the cell cycle. Because failure to reassemble nucleosomes at replication forks blocks DNA replication progression in higher eukaryotes and leads to genomic instability, we further underline the importance of the mechanistic link between DNA replication and chromatin duplication.
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Affiliation(s)
- Constance Alabert
- Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee, UK
| | - Zuzana Jasencakova
- Biotech Research and Innovation Centre (BRIC), Health and Medical Faculty, University of Copenhagen, Copenhagen, Denmark
| | - Anja Groth
- Biotech Research and Innovation Centre (BRIC), Health and Medical Faculty, University of Copenhagen, Copenhagen, Denmark.
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87
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Talbert PB, Henikoff S. Histone variants on the move: substrates for chromatin dynamics. Nat Rev Mol Cell Biol 2016; 18:115-126. [PMID: 27924075 DOI: 10.1038/nrm.2016.148] [Citation(s) in RCA: 226] [Impact Index Per Article: 28.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Most histones are assembled into nucleosomes behind the replication fork to package newly synthesized DNA. By contrast, histone variants, which are encoded by separate genes, are typically incorporated throughout the cell cycle. Histone variants can profoundly change chromatin properties, which in turn affect DNA replication and repair, transcription, and chromosome packaging and segregation. Recent advances in the study of histone replacement have elucidated the dynamic processes by which particular histone variants become substrates of histone chaperones, ATP-dependent chromatin remodellers and histone-modifying enzymes. Here, we review histone variant dynamics and the effects of replacing DNA synthesis-coupled histones with their replication-independent variants on the chromatin landscape.
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Affiliation(s)
- Paul B Talbert
- Howard Hughes Medical Institute, Fred Hutchinson Cancer Research Center, 1100 Fairview Avenue North, Seattle, Washington 98109-1024, USA
| | - Steven Henikoff
- Howard Hughes Medical Institute, Fred Hutchinson Cancer Research Center, 1100 Fairview Avenue North, Seattle, Washington 98109-1024, USA
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88
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Morgan MT, Wolberger C. Recognition of ubiquitinated nucleosomes. Curr Opin Struct Biol 2016; 42:75-82. [PMID: 27923209 DOI: 10.1016/j.sbi.2016.11.016] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2016] [Revised: 11/03/2016] [Accepted: 11/15/2016] [Indexed: 11/26/2022]
Abstract
Histone ubiquitination plays a non-degradative role in regulating transcription and the DNA damage response. A mechanistic understanding of this chromatin modification has lagged that of small histone modifications because of the technical challenges in preparing ubiquitinated nucleosomes. The recent structure of the DUB module of the SAGA coactivator complex bound to a nucleosome containing monoubiquitinated H2B has provided the first view of how specialized subunits target this enzyme to its substrate. Single particle electron microscopy of the intact SAGA coactivator suggests how the DUB module and histone acetyltransferase module engage a nucleosomal substrate. A cryo EM study of 53BP1 bound to nucleosomes containing ubiquitinated H2A and H4 methylated at K20 extends our understanding of recognition of biologically distinct combinations of chromatin marks through multivalent interactions.
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Affiliation(s)
- Michael T Morgan
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Cynthia Wolberger
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
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89
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Large-scale ATP-independent nucleosome unfolding by a histone chaperone. Nat Struct Mol Biol 2016; 23:1111-1116. [PMID: 27820806 DOI: 10.1038/nsmb.3321] [Citation(s) in RCA: 69] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2016] [Accepted: 10/13/2016] [Indexed: 12/13/2022]
Abstract
DNA accessibility to regulatory proteins is substantially influenced by nucleosome structure and dynamics. The facilitates chromatin transcription (FACT) complex increases the accessibility of nucleosomal DNA, but the mechanism and extent of its nucleosome reorganization activity are unknown. Here we determined the effects of FACT from the yeast Saccharomyces cerevisiae on single nucleosomes by using single-particle Förster resonance energy transfer (spFRET) microscopy. FACT binding results in dramatic ATP-independent, symmetrical and reversible DNA uncoiling that affects at least 70% of the DNA within a nucleosome, occurs without apparent loss of histones and proceeds via an 'all-or-none' mechanism. A mutated version of FACT is defective in uncoiling, and a histone mutation that suppresses phenotypes caused by this FACT mutation in vivo restores the uncoiling activity in vitro. Thus, FACT-dependent nucleosome unfolding modulates the accessibility of nucleosomal DNA, and this activity is an important function of FACT in vivo.
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90
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Structural Insights into the Association of Hif1 with Histones H2A-H2B Dimer and H3-H4 Tetramer. Structure 2016; 24:1810-1820. [DOI: 10.1016/j.str.2016.08.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2016] [Revised: 08/01/2016] [Accepted: 08/01/2016] [Indexed: 11/22/2022]
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91
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Li W, Chen P, Yu J, Dong L, Liang D, Feng J, Yan J, Wang PY, Li Q, Zhang Z, Li M, Li G. FACT Remodels the Tetranucleosomal Unit of Chromatin Fibers for Gene Transcription. Mol Cell 2016; 64:120-133. [PMID: 27666592 DOI: 10.1016/j.molcel.2016.08.024] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Revised: 05/13/2016] [Accepted: 08/18/2016] [Indexed: 10/21/2022]
Abstract
In eukaryotes, the packaging of genomic DNA into chromatin plays a critical role in gene regulation. However, the dynamic organization of chromatin fibers and its regulatory mechanisms remain poorly understood. Using single-molecule force spectroscopy, we reveal that the tetranucleosomes-on-a-string appears as a stable secondary structure during hierarchical organization of chromatin fibers. The stability of the tetranucleosomal unit is attenuated by histone chaperone FACT (facilitates chromatin transcription) in vitro. Consistent with in vitro observations, our genome-wide analysis further shows that FACT facilitates gene transcription by destabilizing the tetranucleosomal unit of chromatin fibers in yeast. Additionally, we found that the linker histone H1 not only enhances the stability but also facilitates the folding and unfolding kinetics of the outer nucleosomal wrap. Our study demonstrates that the tetranucleosome is a regulatory structural unit of chromatin fibers beyond the nucleosome and provides crucial mechanistic insights into the structure and dynamics of chromatin fibers during gene transcription.
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Affiliation(s)
- Wei Li
- National Laboratory for Condensed Matter Physics and Key Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, China, 100190
| | - Ping Chen
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China, 100101
| | - Juan Yu
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China, 100101
| | - Liping Dong
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China, 100101; Graduate School of University of Chinese Academy of Sciences, Beijing, China, 100049
| | - Dan Liang
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China, 100101; Graduate School of University of Chinese Academy of Sciences, Beijing, China, 100049
| | - Jianxun Feng
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences and Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, China 100871
| | - Jie Yan
- Department of Physics, National University of Singapore, Singapore, 117542; Mechanobiology Institute, National University of Singapore, Singapore, 117411
| | - Peng-Ye Wang
- National Laboratory for Condensed Matter Physics and Key Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, China, 100190
| | - Qing Li
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences and Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, China 100871
| | - Zhiguo Zhang
- Department of Biochemistry and Molecular Biology, Mayo Clinic College of Medicine, 200 First Street SW, Rochester, MN 55905, USA
| | - Ming Li
- National Laboratory for Condensed Matter Physics and Key Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, China, 100190.
| | - Guohong Li
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China, 100101.
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92
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Charles Richard JL, Shukla MS, Menoni H, Ouararhni K, Lone IN, Roulland Y, Papin C, Ben Simon E, Kundu T, Hamiche A, Angelov D, Dimitrov S. FACT Assists Base Excision Repair by Boosting the Remodeling Activity of RSC. PLoS Genet 2016; 12:e1006221. [PMID: 27467129 PMCID: PMC4965029 DOI: 10.1371/journal.pgen.1006221] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2016] [Accepted: 07/06/2016] [Indexed: 01/14/2023] Open
Abstract
FACT, in addition to its role in transcription, is likely implicated in both transcription-coupled nucleotide excision repair and DNA double strand break repair. Here, we present evidence that FACT could be directly involved in Base Excision Repair and elucidate the chromatin remodeling mechanisms of FACT during BER. We found that, upon oxidative stress, FACT is released from transcription related protein complexes to get associated with repair proteins and chromatin remodelers from the SWI/SNF family. We also showed the rapid recruitment of FACT to the site of damage, coincident with the glycosylase OGG1, upon the local generation of oxidized DNA. Interestingly, FACT facilitates uracil-DNA glycosylase in the removal of uracil from nucleosomal DNA thanks to an enhancement in the remodeling activity of RSC. This discloses a novel property of FACT wherein it has a co-remodeling activity and strongly enhances the remodeling capacity of the chromatin remodelers. Altogether, our data suggest that FACT may acts in concert with RSC to facilitate excision of DNA lesions during the initial step of BER. In the nucleus, DNA is packaged into chromatin. The repeating unit of chromatin, the nucleosome, consists of a histone octamer around which DNA is wrapped into two superhelical turns. The nucleosome is a barrier for various nuclear processes which require access to DNA. To repair lesions on DNA, this barrier has to be overcome by either nucleosome remodeling or by histone eviction. Here we present evidence that FACT, a protein known to be involved in transcription, is also involved in BER, by boosting nucleosome remodeling. Upon in vivo oxidized DNA lesion induction, FACT exhibits a BER-like protein behavior, and it is recruited to the sites of DNA damages. In vitro experiments show that FACT boosts the remodeling activity of the chromatin remodeler RSC and is implicated in DNA repair. The presence of FACT greatly facilitates the removal of uracil from nucleosomal, but not from naked DNA, in a RSC-mediated reaction. Taken collectively, our in vitro and in vivo data reveal a role of FACT in BER by helping the remodeling of chromatin at the sites of lesions.
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Affiliation(s)
- John Lalith Charles Richard
- Université Joseph Fourier-Grenoble 1, INSERM Institut Albert Bonniot U823, Site Santé, Grenoble, France
- Université de Lyon, Laboratoire de Biologie Moléculaire de la Cellule, LBMC CNRS/ENSL/UCBL UMR5239 & Institut NeuroMyoGène–INMG CNRS/UCBL UMR5310, Ecole Normale Supérieure de Lyon, Lyon, France
| | - Manu Shubhdarshan Shukla
- Université Joseph Fourier-Grenoble 1, INSERM Institut Albert Bonniot U823, Site Santé, Grenoble, France
- Université de Lyon, Laboratoire de Biologie Moléculaire de la Cellule, LBMC CNRS/ENSL/UCBL UMR5239 & Institut NeuroMyoGène–INMG CNRS/UCBL UMR5310, Ecole Normale Supérieure de Lyon, Lyon, France
| | - Hervé Menoni
- Université de Lyon, Laboratoire de Biologie Moléculaire de la Cellule, LBMC CNRS/ENSL/UCBL UMR5239 & Institut NeuroMyoGène–INMG CNRS/UCBL UMR5310, Ecole Normale Supérieure de Lyon, Lyon, France
| | - Khalid Ouararhni
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, CNRS/INSERM/ULP, Parc d’Innovation, Illkirch, France
| | - Imtiaz Nisar Lone
- Université de Lyon, Laboratoire de Biologie Moléculaire de la Cellule, LBMC CNRS/ENSL/UCBL UMR5239 & Institut NeuroMyoGène–INMG CNRS/UCBL UMR5310, Ecole Normale Supérieure de Lyon, Lyon, France
| | - Yohan Roulland
- Université Joseph Fourier-Grenoble 1, INSERM Institut Albert Bonniot U823, Site Santé, Grenoble, France
| | - Christophe Papin
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, CNRS/INSERM/ULP, Parc d’Innovation, Illkirch, France
| | - Elsa Ben Simon
- Université de Lyon, Laboratoire de Biologie Moléculaire de la Cellule, LBMC CNRS/ENSL/UCBL UMR5239 & Institut NeuroMyoGène–INMG CNRS/UCBL UMR5310, Ecole Normale Supérieure de Lyon, Lyon, France
| | - Tapas Kundu
- Transcription and Disease Laboratory, Molecular Biology and Genetics Unit Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, India
| | - Ali Hamiche
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, CNRS/INSERM/ULP, Parc d’Innovation, Illkirch, France
- * E-mail: (AH); (DA); (SD)
| | - Dimitar Angelov
- Université de Lyon, Laboratoire de Biologie Moléculaire de la Cellule, LBMC CNRS/ENSL/UCBL UMR5239 & Institut NeuroMyoGène–INMG CNRS/UCBL UMR5310, Ecole Normale Supérieure de Lyon, Lyon, France
- * E-mail: (AH); (DA); (SD)
| | - Stefan Dimitrov
- Université Joseph Fourier-Grenoble 1, INSERM Institut Albert Bonniot U823, Site Santé, Grenoble, France
- * E-mail: (AH); (DA); (SD)
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93
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Raj R, Lercher L, Mohammed S, Davis BG. Synthetic Nucleosomes Reveal that GlcNAcylation Modulates Direct Interaction with the FACT Complex. Angew Chem Int Ed Engl 2016; 55:8918-22. [PMID: 27272618 PMCID: PMC5111754 DOI: 10.1002/anie.201603106] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Indexed: 12/28/2022]
Abstract
Transcriptional regulation can be established by various post-translational modifications (PTMs) on histone proteins in the nucleosome and by nucleobase modifications on chromosomal DNA. Functional consequences of histone O-GlcNAcylation (O-GlcNAc=O-linked β-N-acetylglucosamine) are largely unexplored. Herein, we generate homogeneously GlcNAcylated histones and nucleosomes by chemical post-translational modification. Mass-spectrometry-based quantitative interaction proteomics reveals a direct interaction between GlcNAcylated nucleosomes and the "facilitates chromatin transcription" (FACT) complex. Preferential binding of FACT to GlcNAcylated nucleosomes may point towards O-GlcNAcylation as one of the triggers for FACT-driven transcriptional control.
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Affiliation(s)
- Ritu Raj
- Department of Chemistry, University of Oxford, Chemistry Research Laboratory, Mansfield Road, Oxford, OX1 3TA, UK
| | - Lukas Lercher
- Department of Chemistry, University of Oxford, Chemistry Research Laboratory, Mansfield Road, Oxford, OX1 3TA, UK
| | - Shabaz Mohammed
- Department of Chemistry, University of Oxford, Chemistry Research Laboratory, Mansfield Road, Oxford, OX1 3TA, UK
| | - Benjamin G Davis
- Department of Chemistry, University of Oxford, Chemistry Research Laboratory, Mansfield Road, Oxford, OX1 3TA, UK.
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94
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Mao P, Kyriss MNM, Hodges AJ, Duan M, Morris RT, Lavine MD, Topping TB, Gloss LM, Wyrick JJ. A basic domain in the histone H2B N-terminal tail is important for nucleosome assembly by FACT. Nucleic Acids Res 2016; 44:9142-9152. [PMID: 27369377 PMCID: PMC5100577 DOI: 10.1093/nar/gkw588] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Accepted: 06/20/2016] [Indexed: 12/28/2022] Open
Abstract
Nucleosome assembly in vivo requires assembly factors, such as histone chaperones, to bind to histones and mediate their deposition onto DNA. In yeast, the essential histone chaperone FACT (FAcilitates Chromatin Transcription) functions in nucleosome assembly and H2A–H2B deposition during transcription elongation and DNA replication. Recent studies have identified candidate histone residues that mediate FACT binding to histones, but it is not known which histone residues are important for FACT to deposit histones onto DNA during nucleosome assembly. In this study, we report that the histone H2B repression (HBR) domain within the H2B N-terminal tail is important for histone deposition by FACT. Deletion of the HBR domain causes significant defects in histone occupancy in the yeast genome, particularly at HBR-repressed genes, and a pronounced increase in H2A–H2B dimers that remain bound to FACT in vivo. Moreover, the HBR domain is required for purified FACT to efficiently assemble recombinant nucleosomes in vitro. We propose that the interaction between the highly basic HBR domain and DNA plays an important role in stabilizing the nascent nucleosome during the process of histone H2A–H2B deposition by FACT.
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Affiliation(s)
- Peng Mao
- School of Molecular Biosciences and Center for Reproductive Biology, Washington State University, Pullman, WA 99164, USA
| | - McKenna N M Kyriss
- School of Molecular Biosciences and Center for Reproductive Biology, Washington State University, Pullman, WA 99164, USA
| | - Amelia J Hodges
- School of Molecular Biosciences and Center for Reproductive Biology, Washington State University, Pullman, WA 99164, USA
| | - Mingrui Duan
- School of Molecular Biosciences and Center for Reproductive Biology, Washington State University, Pullman, WA 99164, USA
| | - Robert T Morris
- School of Molecular Biosciences and Center for Reproductive Biology, Washington State University, Pullman, WA 99164, USA
| | - Mark D Lavine
- School of Molecular Biosciences and Center for Reproductive Biology, Washington State University, Pullman, WA 99164, USA
| | - Traci B Topping
- School of Molecular Biosciences and Center for Reproductive Biology, Washington State University, Pullman, WA 99164, USA
| | - Lisa M Gloss
- School of Molecular Biosciences and Center for Reproductive Biology, Washington State University, Pullman, WA 99164, USA
| | - John J Wyrick
- School of Molecular Biosciences and Center for Reproductive Biology, Washington State University, Pullman, WA 99164, USA
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95
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Smeenk G, Mailand N. Writers, Readers, and Erasers of Histone Ubiquitylation in DNA Double-Strand Break Repair. Front Genet 2016; 7:122. [PMID: 27446204 PMCID: PMC4923129 DOI: 10.3389/fgene.2016.00122] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Accepted: 06/15/2016] [Indexed: 12/16/2022] Open
Abstract
DNA double-strand breaks (DSBs) are highly cytotoxic DNA lesions, whose faulty repair may alter the content and organization of cellular genomes. To counteract this threat, numerous signaling and repair proteins are recruited hierarchically to the chromatin areas surrounding DSBs to facilitate accurate lesion repair and restoration of genome integrity. In vertebrate cells, ubiquitin-dependent modifications of histones adjacent to DSBs by RNF8, RNF168, and other ubiquitin ligases have a key role in promoting the assembly of repair protein complexes, serving as direct recruitment platforms for a range of genome caretaker proteins and their associated factors. These DNA damage-induced chromatin ubiquitylation marks provide an essential component of a histone code for DSB repair that is controlled by multifaceted regulatory circuits, underscoring its importance for genome stability maintenance. In this review, we provide a comprehensive account of how DSB-induced histone ubiquitylation is sensed, decoded and modulated by an elaborate array of repair factors and regulators. We discuss how these mechanisms impact DSB repair pathway choice and functionality for optimal protection of genome integrity, as well as cell and organismal fitness.
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Affiliation(s)
- Godelieve Smeenk
- Ubiquitin Signaling Group, Protein Signaling Program, Faculty of Health and Medical Sciences, The Novo Nordisk Foundation Center for Protein Research, University of Copenhagen Copenhagen, Denmark
| | - Niels Mailand
- Ubiquitin Signaling Group, Protein Signaling Program, Faculty of Health and Medical Sciences, The Novo Nordisk Foundation Center for Protein Research, University of Copenhagen Copenhagen, Denmark
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96
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Prendergast L, Müller S, Liu Y, Huang H, Dingli F, Loew D, Vassias I, Patel DJ, Sullivan KF, Almouzni G. The CENP-T/-W complex is a binding partner of the histone chaperone FACT. Genes Dev 2016; 30:1313-26. [PMID: 27284163 PMCID: PMC4911930 DOI: 10.1101/gad.275073.115] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Accepted: 05/02/2016] [Indexed: 01/28/2023]
Abstract
Prendergast et al. identified Spt16 and SSRP1, subunits of the H2A–H2B histone chaperone FACT, as CENP-W-binding partners through a proteomic screen. They developed a model in which the FACT chaperone stabilizes the soluble CENP-T/-W complex in the cell and promotes dynamics of exchange, enabling CENP-T/-W deposition at centromeres. The CENP-T/-W histone fold complex, as an integral part of the inner kinetochore, is essential for building a proper kinetochore at the centromere in order to direct chromosome segregation during mitosis. Notably, CENP-T/-W is not inherited at centromeres, and new deposition is absolutely required at each cell cycle for kinetochore function. However, the mechanisms underlying this new deposition of CENP-T/-W at centromeres are unclear. Here, we found that CENP-T deposition at centromeres is uncoupled from DNA synthesis. We identified Spt16 and SSRP1, subunits of the H2A–H2B histone chaperone facilitates chromatin transcription (FACT), as CENP-W binding partners through a proteomic screen. We found that the C-terminal region of Spt16 binds specifically to the histone fold region of CENP-T/-W. Furthermore, depletion of Spt16 impairs CENP-T and CENP-W deposition at endogenous centromeres, and site-directed targeting of Spt16 alone is sufficient to ensure local de novo CENP-T accumulation. We propose a model in which the FACT chaperone stabilizes the soluble CENP-T/-W complex in the cell and promotes dynamics of exchange, enabling CENP-T/-W deposition at centromeres.
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Affiliation(s)
- Lisa Prendergast
- UMR3664, Centre National de la Recherche Scientifique, Institut Curie, PSL (Paris Sciences et Lettres) Research University, F-75005 Paris, France; UMR3664, Centre National de la Recherche Scientifique, University Pierre and Marie Curie Paris 06, Sorbonne Universités, F-75005 Paris, France
| | - Sebastian Müller
- UMR3664, Centre National de la Recherche Scientifique, Institut Curie, PSL (Paris Sciences et Lettres) Research University, F-75005 Paris, France; UMR3664, Centre National de la Recherche Scientifique, University Pierre and Marie Curie Paris 06, Sorbonne Universités, F-75005 Paris, France
| | - Yiwei Liu
- Structural Biology Program, Memorial Sloan-Kettering Cancer Center, New York, New York 10065, USA
| | - Hongda Huang
- Structural Biology Program, Memorial Sloan-Kettering Cancer Center, New York, New York 10065, USA
| | - Florent Dingli
- UMR3664, Centre National de la Recherche Scientifique, Institut Curie, PSL (Paris Sciences et Lettres) Research University, F-75005 Paris, France; Laboratoire de Spectrométrie de Masse Protéomique, Institut Curie, PSL (Paris Sciences et Lettres) Research University Centre de Recherche, Paris 75005, France
| | - Damarys Loew
- UMR3664, Centre National de la Recherche Scientifique, Institut Curie, PSL (Paris Sciences et Lettres) Research University, F-75005 Paris, France; Laboratoire de Spectrométrie de Masse Protéomique, Institut Curie, PSL (Paris Sciences et Lettres) Research University Centre de Recherche, Paris 75005, France
| | - Isabelle Vassias
- UMR3664, Centre National de la Recherche Scientifique, Institut Curie, PSL (Paris Sciences et Lettres) Research University, F-75005 Paris, France; UMR3664, Centre National de la Recherche Scientifique, University Pierre and Marie Curie Paris 06, Sorbonne Universités, F-75005 Paris, France
| | - Dinshaw J Patel
- Structural Biology Program, Memorial Sloan-Kettering Cancer Center, New York, New York 10065, USA
| | - Kevin F Sullivan
- Centre for Chromosome Biology, School of Natural Sciences, National University of Ireland, Galway, Ireland
| | - Geneviève Almouzni
- UMR3664, Centre National de la Recherche Scientifique, Institut Curie, PSL (Paris Sciences et Lettres) Research University, F-75005 Paris, France; UMR3664, Centre National de la Recherche Scientifique, University Pierre and Marie Curie Paris 06, Sorbonne Universités, F-75005 Paris, France
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97
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Raj R, Lercher L, Mohammed S, Davis BG. Synthetic Nucleosomes Reveal that GlcNAcylation Modulates Direct Interaction with the FACT Complex. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201603106] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- Ritu Raj
- Department of Chemistry; University of Oxford, Chemistry Research Laboratory; Mansfield Road Oxford OX1 3TA UK
| | - Lukas Lercher
- Department of Chemistry; University of Oxford, Chemistry Research Laboratory; Mansfield Road Oxford OX1 3TA UK
| | - Shabaz Mohammed
- Department of Chemistry; University of Oxford, Chemistry Research Laboratory; Mansfield Road Oxford OX1 3TA UK
| | - Benjamin G. Davis
- Department of Chemistry; University of Oxford, Chemistry Research Laboratory; Mansfield Road Oxford OX1 3TA UK
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98
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Abstract
Organism viability relies on the stable maintenance of specific chromatin landscapes, established during development, that shape cell functions and identities by driving distinct gene expression programs. Yet epigenome maintenance is challenged during transcription, replication, and repair of DNA damage, all of which elicit dynamic changes in chromatin organization. Here, we review recent advances that have shed light on the specialized mechanisms contributing to the restoration of epigenome structure and function after DNA damage in the mammalian cell nucleus. By drawing a parallel with epigenome maintenance during replication, we explore emerging concepts and highlight open issues in this rapidly growing field. In particular, we present our current knowledge of molecular players that support the coordinated maintenance of genome and epigenome integrity in response to DNA damage, and we highlight how nuclear organization impacts genome stability. Finally, we discuss possible functional implications of epigenome plasticity in response to genotoxic stress.
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Affiliation(s)
- Juliette Dabin
- Epigenome Integrity Group, UMR 7216 CNRS, Paris Diderot University, Sorbonne Paris Cité, 75013 Paris Cedex 13, France
| | - Anna Fortuny
- Epigenome Integrity Group, UMR 7216 CNRS, Paris Diderot University, Sorbonne Paris Cité, 75013 Paris Cedex 13, France
| | - Sophie E Polo
- Epigenome Integrity Group, UMR 7216 CNRS, Paris Diderot University, Sorbonne Paris Cité, 75013 Paris Cedex 13, France.
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99
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Aguilar-Gurrieri C, Larabi A, Vinayachandran V, Patel NA, Yen K, Reja R, Ebong IO, Schoehn G, Robinson CV, Pugh BF, Panne D. Structural evidence for Nap1-dependent H2A-H2B deposition and nucleosome assembly. EMBO J 2016; 35:1465-82. [PMID: 27225933 PMCID: PMC4931181 DOI: 10.15252/embj.201694105] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2016] [Accepted: 04/21/2016] [Indexed: 11/25/2022] Open
Abstract
Nap1 is a histone chaperone involved in the nuclear import of H2A–H2B and nucleosome assembly. Here, we report the crystal structure of Nap1 bound to H2A–H2B together with in vitro and in vivo functional studies that elucidate the principles underlying Nap1‐mediated H2A–H2B chaperoning and nucleosome assembly. A Nap1 dimer provides an acidic binding surface and asymmetrically engages a single H2A–H2B heterodimer. Oligomerization of the Nap1–H2A–H2B complex results in burial of surfaces required for deposition of H2A–H2B into nucleosomes. Chromatin immunoprecipitation‐exonuclease (ChIP‐exo) analysis shows that Nap1 is required for H2A–H2B deposition across the genome. Mutants that interfere with Nap1 oligomerization exhibit severe nucleosome assembly defects showing that oligomerization is essential for the chaperone function. These findings establish the molecular basis for Nap1‐mediated H2A–H2B deposition and nucleosome assembly.
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Affiliation(s)
- Carmen Aguilar-Gurrieri
- European Molecular Biology Laboratory, Grenoble, France Unit for Virus Host-Cell Interactions, Univ. Grenoble Alpes-EMBL-CNRS, Grenoble, France
| | - Amédé Larabi
- European Molecular Biology Laboratory, Grenoble, France Unit for Virus Host-Cell Interactions, Univ. Grenoble Alpes-EMBL-CNRS, Grenoble, France
| | - Vinesh Vinayachandran
- Center for Eukaryotic Gene Regulation, Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA, USA
| | - Nisha A Patel
- Department of Chemistry, University of Oxford, Oxford, UK
| | - Kuangyu Yen
- Department of Cell Biology, Southern Medical University, Guangzhou, China
| | - Rohit Reja
- Center for Eukaryotic Gene Regulation, Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA, USA
| | - Ima-O Ebong
- Department of Chemistry, University of Oxford, Oxford, UK
| | - Guy Schoehn
- Unit for Virus Host-Cell Interactions, Univ. Grenoble Alpes-EMBL-CNRS, Grenoble, France Université Grenoble-Alpes, Grenoble, France Centre National de la Recherche Scientifique (CNRS) IBS, Grenoble, France CEA, IBS, Grenoble, France
| | | | - B Franklin Pugh
- Center for Eukaryotic Gene Regulation, Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA, USA
| | - Daniel Panne
- European Molecular Biology Laboratory, Grenoble, France Unit for Virus Host-Cell Interactions, Univ. Grenoble Alpes-EMBL-CNRS, Grenoble, France
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100
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Solution structure of the isolated histone H2A-H2B heterodimer. Sci Rep 2016; 6:24999. [PMID: 27181506 PMCID: PMC4867618 DOI: 10.1038/srep24999] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Accepted: 04/08/2016] [Indexed: 01/04/2023] Open
Abstract
During chromatin-regulated processes, the histone H2A-H2B heterodimer functions dynamically in and out of the nucleosome. Although detailed crystal structures of nucleosomes have been established, that of the isolated full-length H2A-H2B heterodimer has remained elusive. Here, we have determined the solution structure of human H2A-H2B by NMR coupled with CS-Rosetta. H2A and H2B each contain a histone fold, comprising four α-helices and two β-strands (α1-β1-α2-β2-α3-αC), together with the long disordered N- and C-terminal H2A tails and the long N-terminal H2B tail. The N-terminal αN helix, C-terminal β3 strand, and 310 helix of H2A observed in the H2A-H2B nucleosome structure are disordered in isolated H2A-H2B. In addition, the H2A α1 and H2B αC helices are not well fixed in the heterodimer, and the H2A and H2B tails are not completely random coils. Comparison of hydrogen-deuterium exchange, fast hydrogen exchange, and {(1)H}-(15)N hetero-nuclear NOE data with the CS-Rosetta structure indicates that there is some conformation in the H2A 310 helical and H2B Lys11 regions, while the repression domain of H2B (residues 27-34) exhibits an extended string-like structure. This first structure of the isolated H2A-H2B heterodimer provides insight into its dynamic functions in chromatin.
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