1
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Hu Y, Schwab S, Deiss S, Escudeiro P, van Heesch T, Joiner JD, Vreede J, Hartmann MD, Lupas AN, Alvarez BH, Alva V, Dame RT. Bacterial histone HBb from Bdellovibrio bacteriovorus compacts DNA by bending. Nucleic Acids Res 2024:gkae485. [PMID: 38864377 DOI: 10.1093/nar/gkae485] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Revised: 05/01/2024] [Accepted: 05/24/2024] [Indexed: 06/13/2024] Open
Abstract
Histones are essential for genome compaction and transcription regulation in eukaryotes, where they assemble into octamers to form the nucleosome core. In contrast, archaeal histones assemble into dimers that form hypernucleosomes upon DNA binding. Although histone homologs have been identified in bacteria recently, their DNA-binding characteristics remain largely unexplored. Our study reveals that the bacterial histone HBb (Bd0055) is indispensable for the survival of Bdellovibrio bacteriovorus, suggesting critical roles in DNA organization and gene regulation. By determining crystal structures of free and DNA-bound HBb, we unveil its distinctive dimeric assembly, diverging from those of eukaryotic and archaeal histones, while also elucidating how it binds and bends DNA through interaction interfaces reminiscent of eukaryotic and archaeal histones. Building on this, by employing various biophysical and biochemical approaches, we further substantiated the ability of HBb to bind and compact DNA by bending in a sequence-independent manner. Finally, using DNA affinity purification and sequencing, we reveal that HBb binds along the entire genomic DNA of B. bacteriovorus without sequence specificity. These distinct DNA-binding properties of bacterial histones, showcasing remarkable similarities yet significant differences from their archaeal and eukaryotic counterparts, highlight the diverse roles histones play in DNA organization across all domains of life.
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Affiliation(s)
- Yimin Hu
- Department of Protein Evolution, Max Planck Institute for Biology Tübingen, Tübingen, Germany
| | - Samuel Schwab
- Leiden Institute of Chemistry, Leiden University, Einsteinweg 55, 2333CC Leiden, The Netherlands; Centre for Microbial Cell Biology, Leiden University, Leiden, The Netherlands; Centre for Interdisciplinary Genome Research, Leiden University, Leiden, The Netherlands
| | - Silvia Deiss
- Department of Protein Evolution, Max Planck Institute for Biology Tübingen, Tübingen, Germany
| | - Pedro Escudeiro
- Department of Protein Evolution, Max Planck Institute for Biology Tübingen, Tübingen, Germany
| | - Thor van Heesch
- Van 't Hoff Institute for Molecular Sciences, University of Amsterdam, The Netherlands
| | - Joe D Joiner
- Department of Protein Evolution, Max Planck Institute for Biology Tübingen, Tübingen, Germany
| | - Jocelyne Vreede
- Van 't Hoff Institute for Molecular Sciences, University of Amsterdam, The Netherlands
| | - Marcus D Hartmann
- Department of Protein Evolution, Max Planck Institute for Biology Tübingen, Tübingen, Germany
- Interfaculty Institute of Biochemistry, University of Tübingen, Tübingen, Germany
| | - Andrei N Lupas
- Department of Protein Evolution, Max Planck Institute for Biology Tübingen, Tübingen, Germany
| | - Birte Hernandez Alvarez
- Department of Protein Evolution, Max Planck Institute for Biology Tübingen, Tübingen, Germany
| | - Vikram Alva
- Department of Protein Evolution, Max Planck Institute for Biology Tübingen, Tübingen, Germany
| | - Remus T Dame
- Leiden Institute of Chemistry, Leiden University, Einsteinweg 55, 2333CC Leiden, The Netherlands; Centre for Microbial Cell Biology, Leiden University, Leiden, The Netherlands; Centre for Interdisciplinary Genome Research, Leiden University, Leiden, The Netherlands
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2
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Li NN, Lun DX, Gong N, Meng G, Du XY, Wang H, Bao X, Li XY, Song JW, Hu K, Li L, Li SY, Liu W, Zhu W, Zhang Y, Li J, Yao T, Mou L, Han X, Hao F, Hu Y, Liu L, Zhu H, Wu Y, Liu B. Targeting the chromatin structural changes of antitumor immunity. J Pharm Anal 2024; 14:100905. [PMID: 38665224 PMCID: PMC11043877 DOI: 10.1016/j.jpha.2023.11.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Revised: 09/28/2023] [Accepted: 11/21/2023] [Indexed: 04/28/2024] Open
Abstract
Epigenomic imbalance drives abnormal transcriptional processes, promoting the onset and progression of cancer. Although defective gene regulation generally affects carcinogenesis and tumor suppression networks, tumor immunogenicity and immune cells involved in antitumor responses may also be affected by epigenomic changes, which may have significant implications for the development and application of epigenetic therapy, cancer immunotherapy, and their combinations. Herein, we focus on the impact of epigenetic regulation on tumor immune cell function and the role of key abnormal epigenetic processes, DNA methylation, histone post-translational modification, and chromatin structure in tumor immunogenicity, and introduce these epigenetic research methods. We emphasize the value of small-molecule inhibitors of epigenetic modulators in enhancing antitumor immune responses and discuss the challenges of developing treatment plans that combine epigenetic therapy and immunotherapy through the complex interaction between cancer epigenetics and cancer immunology.
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Affiliation(s)
- Nian-nian Li
- Weifang People's Hospital, Weifang, Shandong, 261000, China
- School of Life Sciences, Nankai University, Tianjin, 300071, China
| | - Deng-xing Lun
- Weifang People's Hospital, Weifang, Shandong, 261000, China
| | - Ningning Gong
- Weifang Traditional Chinese Medicine Hospital, Weifang, Shandong, 261000, China
| | - Gang Meng
- Shaanxi Key Laboratory of Sericulture, Ankang University, Ankang, Shaanxi, 725000, China
| | - Xin-ying Du
- Weifang People's Hospital, Weifang, Shandong, 261000, China
| | - He Wang
- Weifang People's Hospital, Weifang, Shandong, 261000, China
| | - Xiangxiang Bao
- Weifang People's Hospital, Weifang, Shandong, 261000, China
| | - Xin-yang Li
- Guizhou Education University, Guiyang, 550018, China
| | - Ji-wu Song
- Weifang People's Hospital, Weifang, Shandong, 261000, China
| | - Kewei Hu
- Weifang Traditional Chinese Medicine Hospital, Weifang, Shandong, 261000, China
| | - Lala Li
- Guizhou Normal University, Guiyang, 550025, China
| | - Si-ying Li
- Weifang People's Hospital, Weifang, Shandong, 261000, China
| | - Wenbo Liu
- Weifang People's Hospital, Weifang, Shandong, 261000, China
| | - Wanping Zhu
- Weifang People's Hospital, Weifang, Shandong, 261000, China
| | - Yunlong Zhang
- School of Medical Imaging, Weifang Medical University, Weifang, Shandong, 261053, China
| | - Jikai Li
- Department of Bone and Soft Tissue Oncology, Tianjin Hospital, Tianjin, 300299, China
| | - Ting Yao
- School of Life Sciences, Nankai University, Tianjin, 300071, China
- Teda Institute of Biological Sciences & Biotechnology, Nankai University, Tianjin, 300457, China
| | - Leming Mou
- Weifang People's Hospital, Weifang, Shandong, 261000, China
| | - Xiaoqing Han
- Weifang People's Hospital, Weifang, Shandong, 261000, China
| | - Furong Hao
- Weifang People's Hospital, Weifang, Shandong, 261000, China
| | - Yongcheng Hu
- Weifang People's Hospital, Weifang, Shandong, 261000, China
| | - Lin Liu
- School of Life Sciences, Nankai University, Tianjin, 300071, China
| | - Hongguang Zhu
- Weifang People's Hospital, Weifang, Shandong, 261000, China
| | - Yuyun Wu
- Xinqiao Hospital of Army Military Medical University, Chongqing, 400038, China
| | - Bin Liu
- Weifang People's Hospital, Weifang, Shandong, 261000, China
- School of Life Sciences, Nankai University, Tianjin, 300071, China
- Teda Institute of Biological Sciences & Biotechnology, Nankai University, Tianjin, 300457, China
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3
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Wenck BR, Vickerman RL, Burkhart BW, Santangelo TJ. Archaeal histone-based chromatin structures regulate transcription elongation rates. Commun Biol 2024; 7:236. [PMID: 38413771 PMCID: PMC10899632 DOI: 10.1038/s42003-024-05928-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Accepted: 02/16/2024] [Indexed: 02/29/2024] Open
Abstract
Many archaea encode and express histone proteins to compact their genomes. Archaeal and eukaryotic histones share a near-identical fold that permits DNA wrapping through select histone-DNA contacts to generate chromatin-structures that must be traversed by RNA polymerase (RNAP) to generate transcripts. As archaeal histones can spontaneously assemble with a single histone isoform, single-histone chromatin variants provide an idealized platform to detail the impacts of distinct histone-DNA contacts on transcription efficiencies and to detail the role of the conserved cleavage stimulatory factor, Transcription Factor S (TFS), in assisting RNAP through chromatin landscapes. We demonstrate that substitution of histone residues that modify histone-DNA contacts or the three-dimensional chromatin structure result in radically altered transcription elongation rates and pausing patterns. Chromatin-barriers slow and pause RNAP, providing regulatory potential. The modest impacts of TFS on elongation rates through chromatin landscapes is correlated with TFS-dispensability from the archaeon Thermococcus kodakarensis. Our results detail the importance of distinct chromatin structures for archaeal gene expression and provide a unique perspective on the evolution of, and regulatory strategies imposed by, eukaryotic chromatin.
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Affiliation(s)
- Breanna R Wenck
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO, 80523, USA
| | - Robert L Vickerman
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO, 80523, USA
| | - Brett W Burkhart
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO, 80523, USA
| | - Thomas J Santangelo
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO, 80523, USA.
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4
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Ofer S, Blombach F, Erkelens AM, Barker D, Soloviev Z, Schwab S, Smollett K, Matelska D, Fouqueau T, van der Vis N, Kent NA, Thalassinos K, Dame RT, Werner F. DNA-bridging by an archaeal histone variant via a unique tetramerisation interface. Commun Biol 2023; 6:968. [PMID: 37740023 PMCID: PMC10516927 DOI: 10.1038/s42003-023-05348-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Accepted: 09/12/2023] [Indexed: 09/24/2023] Open
Abstract
In eukaryotes, histone paralogues form obligate heterodimers such as H3/H4 and H2A/H2B that assemble into octameric nucleosome particles. Archaeal histones are dimeric and assemble on DNA into 'hypernucleosome' particles of varying sizes with each dimer wrapping 30 bp of DNA. These are composed of canonical and variant histone paralogues, but the function of these variants is poorly understood. Here, we characterise the structure and function of the histone paralogue MJ1647 from Methanocaldococcus jannaschii that has a unique C-terminal extension enabling homotetramerisation. The 1.9 Å X-ray structure of a dimeric MJ1647 species, structural modelling of the tetramer, and site-directed mutagenesis reveal that the C-terminal tetramerization module consists of two alpha helices in a handshake arrangement. Unlike canonical histones, MJ1647 tetramers can bridge two DNA molecules in vitro. Using single-molecule tethered particle motion and DNA binding assays, we show that MJ1647 tetramers bind ~60 bp DNA and compact DNA in a highly cooperative manner. We furthermore show that MJ1647 effectively competes with the transcription machinery to block access to the promoter in vitro. To the best of our knowledge, MJ1647 is the first histone shown to have DNA bridging properties, which has important implications for genome structure and gene expression in archaea.
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Affiliation(s)
- Sapir Ofer
- Institute for Structural and Molecular Biology, Division of Biosciences, University College London, Darwin Building, Gower Street, London, WC1E 6BT, UK
| | - Fabian Blombach
- Institute for Structural and Molecular Biology, Division of Biosciences, University College London, Darwin Building, Gower Street, London, WC1E 6BT, UK
| | - Amanda M Erkelens
- Leiden Institute of Chemistry, Leiden University, Leiden, the Netherlands
| | - Declan Barker
- Institute for Structural and Molecular Biology, Division of Biosciences, University College London, Darwin Building, Gower Street, London, WC1E 6BT, UK
| | - Zoja Soloviev
- Institute for Structural and Molecular Biology, Division of Biosciences, University College London, Darwin Building, Gower Street, London, WC1E 6BT, UK
| | - Samuel Schwab
- Leiden Institute of Chemistry, Leiden University, Leiden, the Netherlands
| | - Katherine Smollett
- Institute for Structural and Molecular Biology, Division of Biosciences, University College London, Darwin Building, Gower Street, London, WC1E 6BT, UK
| | - Dorota Matelska
- Institute for Structural and Molecular Biology, Division of Biosciences, University College London, Darwin Building, Gower Street, London, WC1E 6BT, UK
- Centre for Genomics Research, Discovery Sciences, BioPharmaceuticals R&D, AstraZeneca, Cambridge, UK
| | - Thomas Fouqueau
- Institute for Structural and Molecular Biology, Division of Biosciences, University College London, Darwin Building, Gower Street, London, WC1E 6BT, UK
| | - Nico van der Vis
- Leiden Institute of Chemistry, Leiden University, Leiden, the Netherlands
| | - Nicholas A Kent
- School of Biosciences, Cardiff University, Museum Avenue, Cardiff, CF10 3AX, UK
| | - Konstantinos Thalassinos
- Institute for Structural and Molecular Biology, Division of Biosciences, University College London, Darwin Building, Gower Street, London, WC1E 6BT, UK
| | - Remus T Dame
- Leiden Institute of Chemistry, Leiden University, Leiden, the Netherlands.
| | - Finn Werner
- Institute for Structural and Molecular Biology, Division of Biosciences, University College London, Darwin Building, Gower Street, London, WC1E 6BT, UK.
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5
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Yang J, Son Y, Kang M, Park W. AamA-mediated epigenetic control of genome-wide gene expression and phenotypic traits in Acinetobacter baumannii ATCC 17978. Microb Genom 2023; 9:mgen001093. [PMID: 37589545 PMCID: PMC10483419 DOI: 10.1099/mgen.0.001093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2022] [Accepted: 08/03/2023] [Indexed: 08/18/2023] Open
Abstract
Individual deletions of three genes encoding orphan DNA methyltransferases resulted in the occurrence of growth defect only in the aamA (encoding AcinetobacterAdenine Methylase A) mutant of A. baumannii strain ATCC 17978. Our single-molecule real-time sequencing-based methylome analysis revealed multiple AamA-mediated DNA methylation sites and proposed a potent census target motif (TTTRAATTYAAA). Loss of Dam led to modulation of genome-wide gene expression, and several Dam-target sites including the promoter region of the trmD operon (rpsP, rimM, trmD, and rplS) were identified through our methylome and transcriptome analyses. AamA methylation also appeared to control the expression of many genes linked to membrane functions (lolAB, lpxO), replication (dnaA) and protein synthesis (trmD operon) in the strain ATCC 17978. Interestingly, cellular resistance against several antibiotics and ethidium bromide through functions of efflux pumps diminished in the absence of the aamA gene, and the complementation of aamA gene restored the wild-type phenotypes. Other tested phenotypic traits such as outer-membrane vesicle production, biofilm formation and virulence were also affected in the aamA mutant. Collectively, our data indicated that epigenetic regulation through AamA-mediated DNA methylation of novel target sites mostly in the regulatory regions could contribute significantly to changes in multiple phenotypic traits in A. baumannii ATCC 17978.
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Affiliation(s)
- Jihye Yang
- Laboratory of Molecular Environmental Microbiology, Department of Environmental Science and Ecological Engineering, Korea University, Seoul, Republic of Korea
| | - Yongjun Son
- Laboratory of Molecular Environmental Microbiology, Department of Environmental Science and Ecological Engineering, Korea University, Seoul, Republic of Korea
| | - Mingyeong Kang
- Laboratory of Molecular Environmental Microbiology, Department of Environmental Science and Ecological Engineering, Korea University, Seoul, Republic of Korea
| | - Woojun Park
- Laboratory of Molecular Environmental Microbiology, Department of Environmental Science and Ecological Engineering, Korea University, Seoul, Republic of Korea
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6
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Stevens KM, Warnecke T. Histone variants in archaea - An undiscovered country. Semin Cell Dev Biol 2023; 135:50-58. [PMID: 35221208 DOI: 10.1016/j.semcdb.2022.02.016] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Revised: 02/20/2022] [Accepted: 02/20/2022] [Indexed: 12/23/2022]
Abstract
Exchanging core histones in the nucleosome for paralogous variants can have important functional ramifications. Many of these variants, and their physiological roles, have been characterized in exquisite detail in model eukaryotes, including humans. In comparison, our knowledge of histone biology in archaea remains rudimentary. This is true in particular for our knowledge of histone variants. Many archaea encode several histone genes that differ in sequence, but do these paralogs make distinct, adaptive contributions to genome organization and regulation in a manner comparable to eukaryotes? Below, we review what we know about histone variants in archaea at the level of structure, regulation, and evolution. In all areas, our knowledge pales when compared to the wealth of insight that has been gathered for eukaryotes. Recent findings, however, provide tantalizing glimpses into a rich and largely undiscovered country that is at times familiar and eukaryote-like and at times strange and uniquely archaeal. We sketch a preliminary roadmap for further exploration of this country; an undertaking that may ultimately shed light not only on chromatin biology in archaea but also on the origin of histone-based chromatin in eukaryotes.
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Affiliation(s)
- Kathryn M Stevens
- Medical Research Council London Institute of Medical Sciences, London, United Kingdom; Institute of Clinical Sciences, Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Tobias Warnecke
- Medical Research Council London Institute of Medical Sciences, London, United Kingdom; Institute of Clinical Sciences, Faculty of Medicine, Imperial College London, London, United Kingdom.
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7
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Erkelens AM, Henneman B, van der Valk RA, Kirolos NCS, Dame RT. Specific DNA binding of archaeal histones HMfA and HMfB. Front Microbiol 2023; 14:1166608. [PMID: 37143534 PMCID: PMC10151503 DOI: 10.3389/fmicb.2023.1166608] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Accepted: 03/27/2023] [Indexed: 05/06/2023] Open
Abstract
In archaea, histones play a role in genome compaction and are involved in transcription regulation. Whereas archaeal histones bind DNA without sequence specificity, they bind preferentially to DNA containing repeats of alternating A/T and G/C motifs. These motifs are also present on the artificial sequence "Clone20," a high-affinity model sequence for binding of the histones from Methanothermus fervidus. Here, we investigate the binding of HMfA and HMfB to Clone20 DNA. We show that specific binding at low protein concentrations (<30 nM) yields a modest level of DNA compaction, attributed to tetrameric nucleosome formation, whereas nonspecific binding strongly compacts DNA. We also demonstrate that histones impaired in hypernucleosome formation are still able to recognize the Clone20 sequence. Histone tetramers indeed exhibit a higher binding affinity for Clone20 than nonspecific DNA. Our results indicate that a high-affinity DNA sequence does not act as a nucleation site, but is bound by a tetramer which we propose is geometrically different from the hypernucleosome. Such a mode of histone binding might permit sequence-driven modulation of hypernucleosome size. These findings might be extrapolated to histone variants that do not form hypernucleosomes. Versatile binding modes of histones could provide a platform for functional interplay between genome compaction and transcription.
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Affiliation(s)
| | - Bram Henneman
- Leiden Institute of Chemistry, Leiden University, Leiden, Netherlands
| | | | | | - Remus T. Dame
- Leiden Institute of Chemistry, Leiden University, Leiden, Netherlands
- Centre for Microbial Cell Biology, Leiden University, Leiden, Netherlands
- *Correspondence: Remus T. Dame,
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8
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Sakrikar S, Schmid A. An archaeal histone-like protein regulates gene expression in response to salt stress. Nucleic Acids Res 2021; 49:12732-12743. [PMID: 34883507 PMCID: PMC8682779 DOI: 10.1093/nar/gkab1175] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Revised: 11/09/2021] [Accepted: 11/12/2021] [Indexed: 12/21/2022] Open
Abstract
Histones, ubiquitous in eukaryotes as DNA-packing proteins, find their evolutionary origins in archaea. Unlike the characterized histone proteins of a number of methanogenic and themophilic archaea, previous research indicated that HpyA, the sole histone encoded in the model halophile Halobacterium salinarum, is not involved in DNA packaging. Instead, it was found to have widespread but subtle effects on gene expression and to maintain wild type cell morphology. However, the precise function of halophilic histone-like proteins remain unclear. Here we use quantitative phenotyping, genetics, and functional genomics to investigate HpyA function. These experiments revealed that HpyA is important for growth and rod-shaped morphology in reduced salinity. HpyA preferentially binds DNA at discrete genomic sites under low salt to regulate expression of ion uptake, particularly iron. HpyA also globally but indirectly activates other ion uptake and nucleotide biosynthesis pathways in a salt-dependent manner. Taken together, these results demonstrate an alternative function for an archaeal histone-like protein as a transcriptional regulator, with its function tuned to the physiological stressors of the hypersaline environment.
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Affiliation(s)
- Saaz Sakrikar
- Biology Department, Duke University, Durham, NC27708, USA
- University Program in Genetics and Genomics, Duke University, Durham, NC27708, USA
| | - Amy K Schmid
- Biology Department, Duke University, Durham, NC27708, USA
- University Program in Genetics and Genomics, Duke University, Durham, NC27708, USA
- Center for Genomics and Computational Biology, Duke University, Durham, NC27708, USA
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9
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Maruyama H, Nambu T, Mashimo C, Okinaga T, Takeyasu K. Single-Molecule/Cell Analyses Reveal Principles of Genome-Folding Mechanisms in the Three Domains of Life. Int J Mol Sci 2021; 22:13432. [PMID: 34948225 PMCID: PMC8707338 DOI: 10.3390/ijms222413432] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Revised: 12/06/2021] [Accepted: 12/10/2021] [Indexed: 11/21/2022] Open
Abstract
Comparative structural/molecular biology by single-molecule analyses combined with single-cell dissection, mass spectroscopy, and biochemical reconstitution have been powerful tools for elucidating the mechanisms underlying genome DNA folding. All genomes in the three domains of life undergo stepwise folding from DNA to 30-40 nm fibers. Major protein players are histone (Eukarya and Archaea), Alba (Archaea), and HU (Bacteria) for fundamental structural units of the genome. In Euryarchaeota, a major archaeal phylum, either histone or HTa (the bacterial HU homolog) were found to wrap DNA. This finding divides archaea into two groups: those that use DNA-wrapping as the fundamental step in genome folding and those that do not. Archaeal transcription factor-like protein TrmBL2 has been suggested to be involved in genome folding and repression of horizontally acquired genes, similar to bacterial H-NS protein. Evolutionarily divergent SMC proteins contribute to the establishment of higher-order structures. Recent results are presented, including the use of Hi-C technology to reveal that archaeal SMC proteins are involved in higher-order genome folding, and the use of single-molecule tracking to reveal the detailed functions of bacterial and eukaryotic SMC proteins. Here, we highlight the similarities and differences in the DNA-folding mechanisms in the three domains of life.
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Affiliation(s)
- Hugo Maruyama
- Department of Bacteriology, Osaka Dental University, Hirakata 573-1121, Japan; (T.N.); (C.M.); (T.O.)
| | - Takayuki Nambu
- Department of Bacteriology, Osaka Dental University, Hirakata 573-1121, Japan; (T.N.); (C.M.); (T.O.)
| | - Chiho Mashimo
- Department of Bacteriology, Osaka Dental University, Hirakata 573-1121, Japan; (T.N.); (C.M.); (T.O.)
| | - Toshinori Okinaga
- Department of Bacteriology, Osaka Dental University, Hirakata 573-1121, Japan; (T.N.); (C.M.); (T.O.)
| | - Kunio Takeyasu
- Graduate School of Biostudies, Kyoto University, Kyoto 606-8501, Japan;
- Center for Biotechnology, National Taiwan University, Taipei 10672, Taiwan
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10
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Stevens KM, Hocher A, Warnecke T. Deep conservation of histone variants in Thermococcales archaea. Genome Biol Evol 2021; 14:6459647. [PMID: 34894218 PMCID: PMC8775648 DOI: 10.1093/gbe/evab274] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/06/2021] [Indexed: 11/12/2022] Open
Abstract
Histones are ubiquitous in eukaryotes where they assemble into nucleosomes, binding and wrapping DNA to form chromatin. One process to modify chromatin and regulate DNA accessibility is the replacement of histones in the nucleosome with paralogous variants. Histones are also present in archaea but whether and how histone variants contribute to the generation of different physiologically relevant chromatin states in these organisms remains largely unknown. Conservation of paralogs with distinct properties can provide prima facie evidence for defined functional roles. We recently revealed deep conservation of histone paralogs with different properties in the Methanobacteriales, but little is known experimentally about these histones. In contrast, the two histones of the model archaeon Thermococcus kodakarensis, HTkA and HTkB, have been examined in some depth, both in vitro and in vivo. HTkA and HTkB exhibit distinct DNA-binding behaviors and elicit unique transcriptional responses when deleted. Here, we consider the evolution of HTkA/B and their orthologs across the order Thermococcales. We find histones with signature HTkA- and HTkB-like properties to be present in almost all Thermococcales genomes. Phylogenetic analysis indicates the presence of one HTkA- and one HTkB-like histone in the ancestor of Thermococcales and long-term maintenance of these two paralogs throughout Thermococcales diversification. Our results support the notion that archaea and eukaryotes have convergently evolved histone variants that carry out distinct adaptive functions. Intriguingly, we also detect more highly diverged histone-fold proteins, related to those found in some bacteria, in several Thermococcales genomes. The functions of these bacteria-type histones remain unknown, but structural modeling suggests that they can form heterodimers with HTkA/B-like histones.
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Affiliation(s)
- Kathryn M Stevens
- Medical Research Council London Institute of Medical Sciences, London, United Kingdom.,Institute of Clinical Sciences, Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Antoine Hocher
- Medical Research Council London Institute of Medical Sciences, London, United Kingdom.,Institute of Clinical Sciences, Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Tobias Warnecke
- Medical Research Council London Institute of Medical Sciences, London, United Kingdom.,Institute of Clinical Sciences, Faculty of Medicine, Imperial College London, London, United Kingdom
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11
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Villain P, da Cunha V, Villain E, Forterre P, Oberto J, Catchpole R, Basta T. The hyperthermophilic archaeon Thermococcus kodakarensis is resistant to pervasive negative supercoiling activity of DNA gyrase. Nucleic Acids Res 2021; 49:12332-12347. [PMID: 34755863 PMCID: PMC8643681 DOI: 10.1093/nar/gkab869] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2021] [Revised: 09/10/2021] [Accepted: 11/02/2021] [Indexed: 01/15/2023] Open
Abstract
In all cells, DNA topoisomerases dynamically regulate DNA supercoiling allowing essential DNA processes such as transcription and replication to occur. How this complex system emerged in the course of evolution is poorly understood. Intriguingly, a single horizontal gene transfer event led to the successful establishment of bacterial gyrase in Archaea, but its emergent function remains a mystery. To better understand the challenges associated with the establishment of pervasive negative supercoiling activity, we expressed the gyrase of the bacterium Thermotoga maritima in a naïve archaeon Thermococcus kodakarensis which naturally has positively supercoiled DNA. We found that the gyrase was catalytically active in T. kodakarensis leading to strong negative supercoiling of plasmid DNA which was stably maintained over at least eighty generations. An increased sensitivity of gyrase-expressing T. kodakarensis to ciprofloxacin suggested that gyrase also modulated chromosomal topology. Accordingly, global transcriptome analyses revealed large scale gene expression deregulation and identified a subset of genes responding to the negative supercoiling activity of gyrase. Surprisingly, the artificially introduced dominant negative supercoiling activity did not have a measurable effect on T. kodakarensis growth rate. Our data suggest that gyrase can become established in Thermococcales archaea without critically interfering with DNA transaction processes.
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Affiliation(s)
- Paul Villain
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France
| | - Violette da Cunha
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France
| | | | - Patrick Forterre
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France.,Archaeal Virology Unit, Institut Pasteur, Paris, France
| | - Jacques Oberto
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France
| | - Ryan Catchpole
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France.,Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA 30602, USA
| | - Tamara Basta
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France
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