1
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Xiang P, Li F, Ma Z, Yue J, Lu C, You Y, Hou L, Yin B, Qiang B, Shu P, Peng X. HCF-1 promotes cell cycle progression by regulating the expression of CDC42. Cell Death Dis 2020; 11:907. [PMID: 33097698 PMCID: PMC7584624 DOI: 10.1038/s41419-020-03094-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2020] [Revised: 08/09/2020] [Accepted: 09/09/2020] [Indexed: 11/16/2022]
Abstract
The eukaryotic cell cycle involves a highly orchestrated series of events in which the cellular genome is replicated during a synthesis (S) phase and each of the two resulting copies are segregated properly during mitosis (M). Host cell factor-1 (HCF-1) is a transcriptional co-regulator that is essential for and has been implicated in basic cellular processes, such as transcriptional regulation and cell cycle progression. Although a series of HCF-1 transcriptional targets have been identified, few functional clues have been provided, especially for chromosome segregation. Our results showed that HCF-1 activated CDC42 expression by binding to the −881 to −575 region upstream of the CDC42 transcription start site, and the regulation of CDC42 expression by HCF-1 was correlated with cell cycle progression. The overexpression of a spontaneously cycling and constitutively active CDC42 mutant (CDC42F28L) rescued G1 phase delay and multinucleate defects in mitosis upon the loss of HCF-1. Therefore, these results establish that HCF-1 ensures proper cell cycle progression by regulating the expression of CDC42, which indicates a possible mechanism of cell cycle coordination and the regulation mode of typical Rho GTPases.
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Affiliation(s)
- Pan Xiang
- State Key Laboratory of Medical Molecular Biology, Department of Molecular Biology and Biochemistry, Institute of Basic Medical Sciences, Medical Primate Research Center, Neuroscience Center, Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Beijing, China
| | - Fei Li
- State Key Laboratory of Medical Molecular Biology, Department of Molecular Biology and Biochemistry, Institute of Basic Medical Sciences, Medical Primate Research Center, Neuroscience Center, Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Beijing, China
| | - Zhihua Ma
- State Key Laboratory of Medical Molecular Biology, Department of Molecular Biology and Biochemistry, Institute of Basic Medical Sciences, Medical Primate Research Center, Neuroscience Center, Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Beijing, China
| | - Jiping Yue
- State Key Laboratory of Medical Molecular Biology, Department of Molecular Biology and Biochemistry, Institute of Basic Medical Sciences, Medical Primate Research Center, Neuroscience Center, Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Beijing, China
| | - Cailing Lu
- State Key Laboratory of Medical Molecular Biology, Department of Molecular Biology and Biochemistry, Institute of Basic Medical Sciences, Medical Primate Research Center, Neuroscience Center, Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Beijing, China
| | - Yuangang You
- State Key Laboratory of Medical Molecular Biology, Department of Molecular Biology and Biochemistry, Institute of Basic Medical Sciences, Medical Primate Research Center, Neuroscience Center, Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Beijing, China
| | - Lin Hou
- State Key Laboratory of Medical Molecular Biology, Department of Molecular Biology and Biochemistry, Institute of Basic Medical Sciences, Medical Primate Research Center, Neuroscience Center, Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Beijing, China
| | - Bin Yin
- State Key Laboratory of Medical Molecular Biology, Department of Molecular Biology and Biochemistry, Institute of Basic Medical Sciences, Medical Primate Research Center, Neuroscience Center, Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Beijing, China
| | - Boqin Qiang
- State Key Laboratory of Medical Molecular Biology, Department of Molecular Biology and Biochemistry, Institute of Basic Medical Sciences, Medical Primate Research Center, Neuroscience Center, Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Beijing, China
| | - Pengcheng Shu
- State Key Laboratory of Medical Molecular Biology, Department of Molecular Biology and Biochemistry, Institute of Basic Medical Sciences, Medical Primate Research Center, Neuroscience Center, Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Beijing, China.
| | - Xiaozhong Peng
- State Key Laboratory of Medical Molecular Biology, Department of Molecular Biology and Biochemistry, Institute of Basic Medical Sciences, Medical Primate Research Center, Neuroscience Center, Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Beijing, China. .,Institute of Medical Biology, Chinese Academy of Medical Sciences, Peking Union Medical College, Kunming, China.
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2
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Fan D, Wang M, Cheng A, Jia R, Yang Q, Wu Y, Zhu D, Zhao X, Chen S, Liu M, Zhang S, Ou X, Mao S, Gao Q, Sun D, Wen X, Liu Y, Yu Y, Zhang L, Tian B, Pan L, Chen X. The Role of VP16 in the Life Cycle of Alphaherpesviruses. Front Microbiol 2020; 11:1910. [PMID: 33013729 PMCID: PMC7461839 DOI: 10.3389/fmicb.2020.01910] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2020] [Accepted: 07/21/2020] [Indexed: 12/12/2022] Open
Abstract
The protein encoded by the UL48 gene of alphaherpesviruses is named VP16 or alpha-gene-transactivating factor (α-TIF). In the early stage of viral replication, VP16 is an important transactivator that can activate the transcription of viral immediate-early genes, and in the late stage of viral replication, VP16, as a tegument, is involved in viral assembly. This review will explain the mechanism of VP16 acting as α-TIF to activate the transcription of viral immediate-early genes, its role in the transition from viral latency to reactivation, and its effects on viral assembly and maturation. In addition, this review also provides new insights for further research on the life cycle of alphaherpesviruses and the role of VP16 in the viral life cycle.
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Affiliation(s)
- Dengjian Fan
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Mingshu Wang
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Anchun Cheng
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Renyong Jia
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Qiao Yang
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Ying Wu
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Dekang Zhu
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Xinxin Zhao
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Shun Chen
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Mafeng Liu
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Shaqiu Zhang
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Xumin Ou
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Sai Mao
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Qun Gao
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Di Sun
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Xingjian Wen
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Yunya Liu
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Yanling Yu
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Ling Zhang
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Bin Tian
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Leichang Pan
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Xiaoyue Chen
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
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3
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Gudkova D, Dergai O, Praz V, Herr W. HCF-2 inhibits cell proliferation and activates differentiation-gene expression programs. Nucleic Acids Res 2019; 47:5792-5808. [PMID: 31049581 PMCID: PMC6582346 DOI: 10.1093/nar/gkz307] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Revised: 04/04/2019] [Accepted: 04/17/2019] [Indexed: 12/20/2022] Open
Abstract
HCF-2 is a member of the host-cell-factor protein family, which arose in early vertebrate evolution as a result of gene duplication. Whereas its paralog, HCF-1, is known to act as a versatile chromatin-associated protein required for cell proliferation and differentiation, much less is known about HCF-2. Here, we show that HCF-2 is broadly present in human and mouse cells, and possesses activities distinct from HCF-1. Unlike HCF-1, which is excluded from nucleoli, HCF-2 is nucleolar—an activity conferred by one and a half C-terminal Fibronectin type 3 repeats and inhibited by the HCF-1 nuclear localization signal. Elevated HCF-2 synthesis in HEK-293 cells results in phenotypes reminiscent of HCF-1-depleted cells, including inhibition of cell proliferation and mitotic defects. Furthermore, increased HCF-2 levels in HEK-293 cells lead to inhibition of cell proliferation and metabolism gene-expression programs with parallel activation of differentiation and morphogenesis gene-expression programs. Thus, the HCF ancestor appears to have evolved into a small two-member protein family possessing contrasting nuclear versus nucleolar localization, and cell proliferation and differentiation functions.
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Affiliation(s)
- Daria Gudkova
- Center for Integrative Genomics, University of Lausanne, 1015 Lausanne, Switzerland
| | - Oleksandr Dergai
- Center for Integrative Genomics, University of Lausanne, 1015 Lausanne, Switzerland
| | - Viviane Praz
- Center for Integrative Genomics, University of Lausanne, 1015 Lausanne, Switzerland.,Swiss Institute of Bioinformatics, University of Lausanne,1015 Lausanne, Switzerland
| | - Winship Herr
- Center for Integrative Genomics, University of Lausanne, 1015 Lausanne, Switzerland
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4
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Minocha S, Herr W. Cortical and Commissural Defects Upon HCF-1 Loss in Nkx2.1-Derived Embryonic Neurons and Glia. Dev Neurobiol 2019; 79:578-595. [PMID: 31207118 PMCID: PMC6771735 DOI: 10.1002/dneu.22704] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Revised: 06/06/2019] [Accepted: 06/06/2019] [Indexed: 11/28/2022]
Abstract
Formation of the cerebral cortex and commissures involves a complex developmental process defined by multiple molecular mechanisms governing proliferation of neuronal and glial precursors, neuronal and glial migration, and patterning events. Failure in any of these processes can lead to malformations. Here, we study the role of HCF-1 in these processes. HCF-1 is a conserved metazoan transcriptional co-regulator long implicated in cell proliferation and more recently in human metabolic disorders and mental retardation. Loss of HCF-1 in a subset of ventral telencephalic Nkx2.1-positive progenitors leads to reduced numbers of GABAergic interneurons and glia, owing not to decreased proliferation but rather to increased apoptosis before cell migration. The loss of these cells leads to development of severe commissural and cortical defects in early postnatal mouse brains. These defects include mild and severe structural defects of the corpus callosum and anterior commissure, respectively, and increased folding of the cortex resembling polymicrogyria. Hence, in addition to its well-established role in cell proliferation, HCF-1 is important for organ development, here the brain.
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Affiliation(s)
- Shilpi Minocha
- Center for Integrative Genomics, GénopodeUniversity of LausanneLausanneCH‐1015Switzerland
| | - Winship Herr
- Center for Integrative Genomics, GénopodeUniversity of LausanneLausanneCH‐1015Switzerland
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5
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Rapid Recapitulation of Nonalcoholic Steatohepatitis upon Loss of Host Cell Factor 1 Function in Mouse Hepatocytes. Mol Cell Biol 2019; 39:MCB.00405-18. [PMID: 30559308 PMCID: PMC6379584 DOI: 10.1128/mcb.00405-18] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Host cell factor 1 (HCF-1), encoded by the ubiquitously expressed X-linked gene Hcfc1, is an epigenetic coregulator important for mouse development and cell proliferation, including during liver regeneration. We used a hepatocyte-specific inducible Hcfc1 knockout allele (called Hcfc1hepKO) to induce HCF-1 loss in hepatocytes of hemizygous Hcfc1hepKO/Y males by 4 days. Host cell factor 1 (HCF-1), encoded by the ubiquitously expressed X-linked gene Hcfc1, is an epigenetic coregulator important for mouse development and cell proliferation, including during liver regeneration. We used a hepatocyte-specific inducible Hcfc1 knockout allele (called Hcfc1hepKO) to induce HCF-1 loss in hepatocytes of hemizygous Hcfc1hepKO/Y males by 4 days. In heterozygous Hcfc1hepKO/+ females, owing to random X-chromosome inactivation, upon Hcfc1hepKO allele induction, a 50/50 mix of HCF-1-positive and -negative hepatocyte clusters is engineered. The livers with Hcfc1hepKO/Y hepatocytes displayed a 21- to 24-day terminal nonalcoholic fatty liver (NAFL), followed by nonalcoholic steatohepatitis (NASH) disease progression typical of severe NAFL disease (NAFLD). In contrast, in livers with heterozygous Hcfc1hepKO/+ hepatocytes, HCF-1-positive hepatocytes replaced HCF-1-negative hepatocytes and revealed only mild NAFL development. Loss of HCF-1 led to loss of PGC1α protein, probably owing to its destabilization, and deregulation of gene expression, particularly of genes involved in mitochondrial structure and function, likely explaining the severe Hcfc1hepKO/Y liver pathology. Thus, HCF-1 is essential for hepatocyte function, likely playing both transcriptional and nontranscriptional roles. These genetically engineered loss-of-HCF-1 mice can be used to study NASH as well as NAFLD resolution.
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6
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Epiblast-specific loss of HCF-1 leads to failure in anterior-posterior axis specification. Dev Biol 2016; 418:75-88. [PMID: 27521049 DOI: 10.1016/j.ydbio.2016.08.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2016] [Revised: 08/08/2016] [Accepted: 08/08/2016] [Indexed: 02/06/2023]
Abstract
Mammalian Host-Cell Factor 1 (HCF-1), a transcriptional co-regulator, plays important roles during the cell-division cycle in cell culture, embryogenesis as well as adult tissue. In mice, HCF-1 is encoded by the X-chromosome-linked Hcfc1 gene. Induced Hcfc1(cKO/+) heterozygosity with a conditional knockout (cKO) allele in the epiblast of female embryos leads to a mixture of HCF-1-positive and -deficient cells owing to random X-chromosome inactivation. These embryos survive owing to the replacement of all HCF-1-deficient cells by HCF-1-positive cells during E5.5 to E8.5 of development. In contrast, complete epiblast-specific loss of HCF-1 in male embryos, Hcfc1(epiKO/Y), leads to embryonic lethality. Here, we characterize this lethality. We show that male epiblast-specific loss of Hcfc1 leads to a developmental arrest at E6.5 with a rapid progressive cell-cycle exit and an associated failure of anterior visceral endoderm migration and primitive streak formation. Subsequently, gastrulation does not take place. We note that the pattern of Hcfc1(epiKO/Y) lethality displays many similarities to loss of β-catenin function. These results reveal essential new roles for HCF-1 in early embryonic cell proliferation and development.
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7
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Minocha S, Sung TL, Villeneuve D, Lammers F, Herr W. Compensatory embryonic response to allele-specific inactivation of the murine X-linked gene Hcfc1. Dev Biol 2016; 412:1-17. [DOI: 10.1016/j.ydbio.2016.02.019] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2015] [Revised: 02/22/2016] [Accepted: 02/22/2016] [Indexed: 01/29/2023]
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8
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Genomic Determinants of THAP11/ZNF143/HCFC1 Complex Recruitment to Chromatin. Mol Cell Biol 2015; 35:4135-46. [PMID: 26416877 DOI: 10.1128/mcb.00477-15] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2015] [Accepted: 09/21/2015] [Indexed: 01/10/2023] Open
Abstract
The THAP11 and ZNF143 transcription factors recognize overlapping DNA sequences and are reported to exhibit signs of both competitive and cooperative binding. HCFC1 serves as a scaffold protein, bridging interactions between transcription factors, including THAP11 and ZNF143, and transcriptional coregulators. The exact mechanism of how DNA sequences guide the recruitment of the THAP11/ZNF143/HCFC1 complex to chromatin is still controversial. In this study, we use chromosomally integrated synthetic constructs and clustered regularly interspaced short palindromic repeat (CRISPR)-Cas9-mediated approaches in intact cells to elucidate the role of the DNA sequence in the recruitment of this complex and to establish its biological relevance. We show that the ACTACA submotif, shared by both THAP11 and ZNF143, directs the recruitment of THAP11 and HCFC1 to ZNF143-occupied loci. Importantly, its position, spacing, and orientation relative to the ZNF143 core motif are critical for this action. CRISPR-Cas9-mediated alterations of the ACTACA submotif at endogenous promoters recapitulated results obtained with synthetic constructs and resulted in altered gene transcription and histone modifications at targeted promoters. Our in vivo approaches provide strong evidence for the molecular role of the ACTACA submotif in THAP11, ZNF143, and HCFC1 cooperative recruitment to chromatin and its biological role in target gene expression.
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9
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Reilly PT, Afzal S, Wakeham A, Haight J, You-Ten A, Zaugg K, Dembowy J, Young A, Mak TW. Generation and characterization of the Anp32e-deficient mouse. PLoS One 2010; 5:e13597. [PMID: 21049064 PMCID: PMC2964292 DOI: 10.1371/journal.pone.0013597] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2010] [Accepted: 10/01/2010] [Indexed: 01/17/2023] Open
Abstract
Background Accumulated literature suggests that the acidic nuclear phosphoprotein 32 kilodalton (Anp32) proteins control multiple cellular activities through different molecular mechanisms. Like other Anp32 family members, Anp32e (a.k.a. Cpd1, PhapIII) has been conserved throughout vertebrate evolution, suggesting that it has an important function in organismal survival. Principal Findings Here, we demonstrate that the Anp32e gene can be deleted in mice without any apparent effect on their wellbeing. No defects in thymocyte apoptosis in response to various stresses, fibroblast growth, gross behaviour, physical ability, or pathogenesis were defined. Furthermore, combined deletion of Anp32a and Anp32e also resulted in a viable and apparently healthy mouse. Significance These results provide evidence that significant functional redundancy exists among Anp32 family members.
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Affiliation(s)
- Patrick T. Reilly
- Department of Cellular and Molecular Research, National Cancer Centre Singapore, Singapore, Singapore
- Campbell Family Cancer Research Institute, University Health Network, Toronto, Ontario, Canada
| | - Samia Afzal
- Campbell Family Cancer Research Institute, University Health Network, Toronto, Ontario, Canada
- Graduate Program in Immunology, University of Toronto, Toronto, Ontario, Canada
| | - Andrew Wakeham
- Campbell Family Cancer Research Institute, University Health Network, Toronto, Ontario, Canada
| | - Jillian Haight
- Campbell Family Cancer Research Institute, University Health Network, Toronto, Ontario, Canada
| | - Annick You-Ten
- Campbell Family Cancer Research Institute, University Health Network, Toronto, Ontario, Canada
| | - Kathrin Zaugg
- Campbell Family Cancer Research Institute, University Health Network, Toronto, Ontario, Canada
| | - Joanna Dembowy
- Campbell Family Cancer Research Institute, University Health Network, Toronto, Ontario, Canada
| | - Ashley Young
- Campbell Family Cancer Research Institute, University Health Network, Toronto, Ontario, Canada
| | - Tak W. Mak
- Department of Cellular and Molecular Research, National Cancer Centre Singapore, Singapore, Singapore
- Campbell Family Cancer Research Institute, University Health Network, Toronto, Ontario, Canada
- * E-mail:
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10
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Mangone M, Myers MP, Herr W. Role of the HCF-1 basic region in sustaining cell proliferation. PLoS One 2010; 5:e9020. [PMID: 20126307 PMCID: PMC2814863 DOI: 10.1371/journal.pone.0009020] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2009] [Accepted: 01/06/2010] [Indexed: 01/15/2023] Open
Abstract
Background The human herpes simplex virus-associated host cell factor 1 (HCF-1) is a conserved human transcriptional co-regulator that links positive and negative histone modifying activities with sequence-specific DNA-binding transcription factors. It is synthesized as a 2035 amino acid precursor that is cleaved to generate an amino- (HCF-1N) terminal subunit, which promotes G1-to-S phase progression, and a carboxy- (HCF-1C) terminal subunit, which controls multiple aspects of cell division during M phase. The HCF-1N subunit contains a Kelch domain that tethers HCF-1 to sequence-specific DNA-binding transcription factors, and a poorly characterized so called “Basic” region (owing to a high ratio of basic vs. acidic amino acids) that is required for cell proliferation and has been shown to associate with the Sin3 histone deacetylase (HDAC) component. Here we studied the role of the Basic region in cell proliferation and G1-to-S phase transition assays. Methodology/Principal Findings Surprisingly, much like the transcriptional activation domains of sequence-specific DNA-binding transcription factors, there is no unique sequence within the Basic region required for promoting cell proliferation or G1-to-S phase transition. Indeed, the ability to promote these activities is size dependent such that the shorter the Basic region segment the less activity observed. We find, however, that the Basic region requirements for promoting cell proliferation in a temperature-sensitive tsBN67 cell assay are more stringent than for G1-to-S phase progression in an HCF-1 siRNA-depletion HeLa-cell assay. Thus, either half of the Basic region alone can support G1-to-S phase progression but not cell proliferation effectively in these assays. Nevertheless, the Basic region displays considerable structural plasticity because each half is able to promote cell proliferation when duplicated in tandem. Consistent with a potential role in promoting cell-cycle progression, the Sin3a HDAC component can associate independently with either half of the Basic region fused to the HCF-1 Kelch domain. Conclusions/Significance While conserved, the HCF-1 Basic region displays striking structural flexibility for controlling cell proliferation.
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Affiliation(s)
- Marco Mangone
- Watson School of Biological Sciences, Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, United States of America
| | - Michael P. Myers
- Watson School of Biological Sciences, Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, United States of America
| | - Winship Herr
- Watson School of Biological Sciences, Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, United States of America
- * E-mail:
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11
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Kristie TM, Liang Y, Vogel JL. Control of alpha-herpesvirus IE gene expression by HCF-1 coupled chromatin modification activities. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2009; 1799:257-65. [PMID: 19682612 DOI: 10.1016/j.bbagrm.2009.08.003] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2009] [Revised: 07/15/2009] [Accepted: 08/01/2009] [Indexed: 01/17/2023]
Abstract
The immediate early genes of the alpha-herpesviruses HSV and VZV are transcriptionally regulated by viral and cellular factors in a complex combinatorial manner. Despite this complexity and the apparent redundancy of activators, the expression of the viral IE genes is critically dependent upon the cellular transcriptional coactivator HCF-1. Although the role of HCF-1 had remained elusive, recent studies have demonstrated that the protein is a component of multiple chromatin modification complexes including the Set1/MLL1 histone H3K4 methyltransferases. Studies using model viral promoter-reporter systems as well as analyses of components recruited to the viral genome during the initiation of infection have elucidated the significance of HCF-1 chromatin modification complexes in contributing to the final state of modified histones assembled on the viral IE promoters. Strikingly, the absence of HCF-1 results in the accumulation of nucleosomes bearing repressive marks on the viral IE promoters and silencing of viral gene expression.
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Affiliation(s)
- Thomas M Kristie
- Laboratory of Viral Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 4-129, 4 Center Drive, Bethesda, Maryland 20892, USA.
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12
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Lee S, Horn V, Julien E, Liu Y, Wysocka J, Bowerman B, Hengartner MO, Herr W. Epigenetic regulation of histone H3 serine 10 phosphorylation status by HCF-1 proteins in C. elegans and mammalian cells. PLoS One 2007; 2:e1213. [PMID: 18043729 PMCID: PMC2082077 DOI: 10.1371/journal.pone.0001213] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2007] [Accepted: 10/30/2007] [Indexed: 12/02/2022] Open
Abstract
BACKGROUND The human herpes simplex virus (HSV) host cell factor HCF-1 is a transcriptional coregulator that associates with both histone methyl- and acetyltransferases, and a histone deacetylase and regulates cell proliferation and division. In HSV-infected cells, HCF-1 associates with the viral protein VP16 to promote formation of a multiprotein-DNA transcriptional activator complex. The ability of HCF proteins to stabilize this VP16-induced complex has been conserved in diverse animal species including Drosophila melanogaster and Caenorhabditis elegans suggesting that VP16 targets a conserved cellular function of HCF-1. METHODOLOGY/PRINCIPAL FINDINGS To investigate the role of HCF proteins in animal development, we have characterized the effects of loss of the HCF-1 homolog in C. elegans, called Ce HCF-1. Two large hcf-1 deletion mutants (pk924 and ok559) are viable but display reduced fertility. Loss of Ce HCF-1 protein at reduced temperatures (e.g., 12 degrees C), however, leads to a high incidence of embryonic lethality and early embryonic mitotic and cytokinetic defects reminiscent of mammalian cell-division defects upon loss of HCF-1 function. Even when viable, however, at normal temperature, mutant embryos display reduced levels of phospho-histone H3 serine 10 (H3S10P), a modification implicated in both transcriptional and mitotic regulation. Mammalian cells with defective HCF-1 also display defects in mitotic H3S10P status. CONCLUSIONS/SIGNIFICANCE These results suggest that HCF-1 proteins possess conserved roles in the regulation of cell division and mitotic histone phosphorylation.
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Affiliation(s)
- Soyoung Lee
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, United States of America
- Program in Molecular and Cellular Biology, Stony Brook University, Stony Brook, New York, United States of America
| | - Virginie Horn
- Center for Integrative Genomics, University of Lausanne, Génopode, Lausanne, Switzerland
| | - Eric Julien
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, United States of America
| | - Yi Liu
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, United States of America
| | - Joanna Wysocka
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, United States of America
| | - Bruce Bowerman
- Institute of Molecular Biology, University of Oregon, Eugene, Oregon, United States of America
| | - Michael O. Hengartner
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, United States of America
| | - Winship Herr
- Center for Integrative Genomics, University of Lausanne, Génopode, Lausanne, Switzerland
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, United States of America
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13
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Capotosti F, Hsieh JJD, Herr W. Species selectivity of mixed-lineage leukemia/trithorax and HCF proteolytic maturation pathways. Mol Cell Biol 2007; 27:7063-72. [PMID: 17698583 PMCID: PMC2168920 DOI: 10.1128/mcb.00769-07] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Site-specific proteolytic processing plays important roles in the regulation of cellular activities. The histone modification activity of the human trithorax group mixed-lineage leukemia (MLL) protein and the cell cycle regulatory activity of the cell proliferation factor herpes simplex virus host cell factor 1 (HCF-1) are stimulated by cleavage of precursors that generates stable heterodimeric complexes. MLL is processed by a protease called taspase 1, whereas the precise mechanisms of HCF-1 maturation are unclear, although they are known to depend on a series of sequence repeats called HCF-1(PRO) repeats. We demonstrate here that the Drosophila homologs of MLL and HCF-1, called Trithorax and dHCF, are both cleaved by Drosophila taspase 1. Although highly related, the human and Drosophila taspase 1 proteins display cognate species specificity. Thus, human taspase 1 preferentially cleaves MLL and Drosophila taspase 1 preferentially cleaves Trithorax, consistent with coevolution of taspase 1 and MLL/Trithorax proteins. HCF proteins display even greater species-specific divergence in processing: whereas dHCF is cleaved by the Drosophila taspase 1, human and mouse HCF-1 maturation is taspase 1 independent. Instead, human and Xenopus HCF-1PRO repeats are cleaved in vitro by a human proteolytic activity with novel properties. Thus, from insects to humans, HCF proteins have conserved proteolytic maturation but evolved different mechanisms.
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Affiliation(s)
- Francesca Capotosti
- Center for Integrative Genomics, University of Lausanne, Génopode Building, 1015 Lausanne, Switzerland
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14
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Knez J, Piluso D, Bilan P, Capone JP. Host Cell Factor-1 and E2F4 Interact Via Multiple Determinants in Each Protein. Mol Cell Biochem 2006; 288:79-90. [PMID: 16633736 DOI: 10.1007/s11010-006-9122-x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2005] [Accepted: 01/09/2006] [Indexed: 12/17/2022]
Abstract
Host Cell Factor (HCF-1) is a conserved, essential protein initially identified as a co-regulator for the Herpes Simplex Virus transactivator VP16. HCF-1 is variously involved in regulating transcription, splicing, cell proliferation and cytokinesis; however, its mechanisms of action remain unknown. HCF-1 function is manifested through an increasing assortment of cellular factors that target different regions of the protein. Several HCF-1 partners target the amino-terminal kelch domain of HCF-1 (residues 1-380) via a consensus HCF-binding motif (HBM) comprising the tetrapeptide (D/E)HXY. Searches of sequence databases indicated that this motif is present in E2F1 and E2F4, two members of the E2F family of cell cycle regulators. We show here that E2F4 specifically and directly interacts with HCF-1. Mutational analysis showed E2F4 independently targets the kelch domain and the basic domain (residues 450-902) of HCF-1, both of which are required for normal cell-cycle progression via separate determinants. The HBM-containing domain of E2F4 was necessary for interaction with the kelch domain of HCF-1 but not for interaction with the basic domain. Mutations in the HCF-1 kelch domain known to block cell growth abrogated E2F4 binding to the kelch domain in the absence but not in the presence of the juxtaposed basic region. Functionally, HCF-1 co-activated E2F4/DP-1 in transient transfection assays, while E2F4 blocked HCF-1-dependent rescue of a cell line that harbors a temperature sensitive mutant of HCF-1 that causes growth arrest. Our findings show that HCF-1 and E2F4 interact via multiple determinants and suggest a linkage between E2F4 and HCF-1 cell growth pathways.
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Affiliation(s)
- Jozo Knez
- Department of Biochemistry and Biomedical Sciences, McMaster University Medical Center, McMaster University, 1200 Main St. W., Hamilton, Ontario, L8N 3Z5, Canada
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15
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Herbst A, Hemann MT, Tworkowski KA, Salghetti SE, Lowe SW, Tansey WP. A conserved element in Myc that negatively regulates its proapoptotic activity. EMBO Rep 2005; 6:177-83. [PMID: 15678160 PMCID: PMC1299243 DOI: 10.1038/sj.embor.7400333] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2004] [Revised: 12/13/2004] [Accepted: 12/15/2004] [Indexed: 01/03/2023] Open
Abstract
Myc is an oncoprotein transcription factor that promotes cell proliferation and apoptosis. Analysis of highly conserved elements within vertebrate Myc proteins has been instrumental in defining the functions of the Myc protein. Here, we probe the role of a highly conserved, but little studied, element within the central region of c-Myc, termed 'Myc box III' (MbIII). We show that MbIII is important for transcriptional repression by Myc, and for transformation both in vitro and in a mouse model of lymphomagenesis. Curiously, disruption of MbIII decreases transformation activity by increasing the efficiency with which Myc can induce apoptosis, suggesting that MbIII is a negative regulator of programmed cell death. These findings reveal a role for MbIII in Myc biology, and establish that the oncogenic capacity of Myc is linked directly to its ability to temper the apoptotic response.
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Affiliation(s)
- Andreas Herbst
- Cold Spring Harbor Laboratory, 1 Bungtown Road, Cold Spring Harbor, New York 11724, USA
- Labor E01 304, Forschungslabor B, Med. Klinik II, Klinikum Grosshadern, Marchioninistrasse 15, 80333 Munich, Germany
| | - Michael T Hemann
- Cold Spring Harbor Laboratory, 1 Bungtown Road, Cold Spring Harbor, New York 11724, USA
| | - Kathryn A Tworkowski
- Cold Spring Harbor Laboratory, 1 Bungtown Road, Cold Spring Harbor, New York 11724, USA
- Molecular and Cellular Biology Program, State University of New York at Stony Brook, Stony Brook, New York 11794, USA
| | - Simone E Salghetti
- Cold Spring Harbor Laboratory, 1 Bungtown Road, Cold Spring Harbor, New York 11724, USA
| | - Scott W Lowe
- Cold Spring Harbor Laboratory, 1 Bungtown Road, Cold Spring Harbor, New York 11724, USA
| | - William P Tansey
- Cold Spring Harbor Laboratory, 1 Bungtown Road, Cold Spring Harbor, New York 11724, USA
- Tel: +1 516 367 8436; Fax: +1 516 367 8874; E-mail:
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16
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Julien E, Herr W. A switch in mitotic histone H4 lysine 20 methylation status is linked to M phase defects upon loss of HCF-1. Mol Cell 2005; 14:713-25. [PMID: 15200950 DOI: 10.1016/j.molcel.2004.06.008] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2003] [Revised: 04/23/2004] [Accepted: 04/27/2004] [Indexed: 11/24/2022]
Abstract
The abundant chromatin-associated human factor HCF-1 is a heterodimeric complex of HCF-1N and HCF-1C subunits that are essential for two stages of the cell cycle. The HCF-1N subunit promotes G1 phase progression, whereas the HCF-1C subunit ensures proper cytokinesis at completion of M phase. How the HCF-1C subunit functions is unknown. Here, we show that HCF-1C subunit depletion causes extensive mitotic defects, including a switch from monomethyl to dimethyl lysine 20 of histone H4 (H4-K20) and defective chromosome alignment and segregation. Consistent with these activities, the HCF-1C subunit can associate with chromatin independently of the HCF-1N subunit and regulates the expression of the H4-K20 methyltransferase PR-Set7. Indeed, upregulation of PR-Set7 expression upon loss of HCF-1 leads to improper mitotic H4-K20 methylation and cytokinesis defects. These results establish the HCF-1C subunit as an important M phase regulator and suggest that H4-K20 methylation status contributes to chromosome behavior during mitosis and proper cytokinesis.
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Affiliation(s)
- Eric Julien
- Cold Spring Harbor Laboratory, 1 Bungtown Road, Cold Spring Harbor, NY 11724, USA
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17
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Abstract
HCF-1 is a transcriptional cofactor required for activation of herpes simplex virus immediate-early genes by VP16 as well as less clearly defined roles in cell proliferation, cytokinesis, and spliceosome formation. It is expressed as a large precursor that undergoes proteolysis to yield two subunits that remain stably associated. VP16 uses a degenerate 4-amino acid sequence, known as the HCF-binding motif, to bind to a six-bladed beta-propeller domain at the N terminus of HCF-1. Functional HCF-binding motifs are also found in LZIP and Zhangfei, two cellular bZIP transcription factors of unknown function. Here we show that the HCF-binding motif occurs in a wide spectrum of DNA-binding proteins and transcriptional cofactors. Three well characterized examples were further analyzed for their ability to use HCF-1 as a coactivator. Krox20, a zinc finger transcription factor required for Schwann cell differentiation, and E2F4, a cell cycle regulator, showed a strong requirement for functional HCF-1 to activate transcription. In contrast, activation by estrogen receptor-alpha did not display HCF dependence. In Krox20, the HCF-binding motif lies within the N-terminal activation domain and mutation of this sequence diminishes both transactivation and association with the HCF-1 beta-propeller. The activation domain in the C-terminal subunit of HCF-1 contributes to activation by Krox20, possibly through recruitment of p300. These results suggest that HCF-1 is recruited by many different classes of cellular transcription factors and is therefore likely to be required for a variety of cellular processes including cell cycle progression and development.
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Affiliation(s)
| | - Angus C. Wilson
- To whom correspondence should be addressed: Dept. of Microbiology, 550 First Ave., New York, NY 10016. Tel.: 212-263-0206; Fax: 212-263-8276;
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18
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Wysocka J, Herr W. The herpes simplex virus VP16-induced complex: the makings of a regulatory switch. Trends Biochem Sci 2003; 28:294-304. [PMID: 12826401 DOI: 10.1016/s0968-0004(03)00088-4] [Citation(s) in RCA: 226] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
When herpes simplex virus (HSV) infects human cells, it is able to enter two modes of infection: lytic and latent. A key activator of lytic infection is a virion protein called VP16, which, upon infection of a permissive cell, forms a transcriptional regulatory complex with two cellular proteins - the POU-domain transcription factor Oct-1 and the cell-proliferation factor HCF-1 - to activate transcription of the first set of expressed viral genes. This regulatory complex, called the VP16-induced complex, reveals mechanisms of combinatorial control of transcription. The activities of Oct-1 and HCF-1 - two important regulators of cellular gene expression and proliferation - illuminate strategies by which HSV might coexist with its host.
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19
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Julien E, Herr W. Proteolytic processing is necessary to separate and ensure proper cell growth and cytokinesis functions of HCF-1. EMBO J 2003; 22:2360-9. [PMID: 12743030 PMCID: PMC156000 DOI: 10.1093/emboj/cdg242] [Citation(s) in RCA: 103] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
HCF-1 is a highly conserved and abundant chromatin-associated host cell factor required for transcriptional activation of herpes simplex virus immediate-early genes by the virion protein VP16. HCF-1 exists as a heterodimeric complex of associated N- (HCF-1(N)) and C- (HCF-1(C)) terminal subunits that result from proteolytic processing of a precursor protein. We have used small-interfering RNA (siRNA) to inactivate HCF-1 in an array of normal and transformed mammalian cells to identify its cellular functions. Our results show that HCF-1 is a broadly acting regulator of two stages of the cell cycle: exit from mitosis, where it ensures proper cytokinesis, and passage through the G(1) phase, where it promotes cell cycle progression. Proteolytic processing is necessary to separate and ensure these two HCF-1 activities, which are performed by separate HCF-1 subunits: the HCF-1(N) subunit promotes passage through the G(1) phase whereas the HCF-1(C) subunit is involved in proper exit from mitosis. These results suggest that HCF-1 links the regulation of exit from mitosis and the G(1) phase of cell growth, possibly to coordinate the reactivation of gene expression after mitosis.
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Affiliation(s)
- Eric Julien
- Cold Spring Harbor Laboratory, NY 11724, USA
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20
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Abstract
Myc is an oncoprotein transcription factor that plays a prominent role in cancer. Like many transcription factors, Myc is an unstable protein that is destroyed by ubiquitin (Ub)-mediated proteolysis. Here, we report that the oncoprotein and Ub ligase Skp2 regulates Myc ubiquitylation and stability. Because of the growing number of Ub ligases that function as transcriptional coactivators, we speculated that Skp2 might also regulate Myc's transcriptional activity. Consistent with this model, we also show that Skp2 is a transcriptional coactivator for Myc, recognizing an essential element within the Myc activation domain and activating Myc target genes. These data suggest that Skp2 functions to connect Myc activity and destruction, and reveal an unexpected oncoprotein connection that may play an important role in controlling cell growth in normal and cancer cells.
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Affiliation(s)
- So Young Kim
- Cold Spring Harbor Laboratory, 1 Bungtown Road, Cold Spring Harbor, NY 11724, USA
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21
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Wysocka J, Myers MP, Laherty CD, Eisenman RN, Herr W. Human Sin3 deacetylase and trithorax-related Set1/Ash2 histone H3-K4 methyltransferase are tethered together selectively by the cell-proliferation factor HCF-1. Genes Dev 2003; 17:896-911. [PMID: 12670868 PMCID: PMC196026 DOI: 10.1101/gad.252103] [Citation(s) in RCA: 314] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The abundant and chromatin-associated protein HCF-1 is a critical player in mammalian cell proliferation as well as herpes simplex virus (HSV) transcription. We show here that separate regions of HCF-1 critical for its role in cell proliferation associate with the Sin3 histone deacetylase (HDAC) and a previously uncharacterized human trithorax-related Set1/Ash2 histone methyltransferase (HMT). The Set1/Ash2 HMT methylates histone H3 at Lys 4 (K4), but not if the neighboring K9 residue is already methylated. HCF-1 tethers the Sin3 and Set1/Ash2 transcriptional regulatory complexes together even though they are generally associated with opposite transcriptional outcomes: repression and activation of transcription, respectively. Nevertheless, this tethering is context-dependent because the transcriptional activator VP16 selectively binds HCF-1 associated with the Set1/Ash2 HMT complex in the absence of the Sin3 HDAC complex. These results suggest that HCF-1 can broadly regulate transcription, both positively and negatively, through selective modulation of chromatin structure.
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Affiliation(s)
- Joanna Wysocka
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA
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22
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Reilly PT, Wysocka J, Herr W. Inactivation of the retinoblastoma protein family can bypass the HCF-1 defect in tsBN67 cell proliferation and cytokinesis. Mol Cell Biol 2002; 22:6767-78. [PMID: 12215534 PMCID: PMC134044 DOI: 10.1128/mcb.22.19.6767-6778.2002] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Owing to a single missense mutation in the cell proliferation factor HCF-1, the temperature-sensitive tsBN67 hamster cell line arrests proliferation at nonpermissive temperatures, primarily in a G(0)/G(1) state, and displays temperature-sensitive cytokinesis defects. The HCF-1 mutation in tsBN67 cells also causes a temperature-sensitive dissociation of HCF-1 from chromatin prior to cell proliferation arrest, suggesting that HCF-1-chromatin association is important for mammalian-cell proliferation. Here, we report that the simian virus 40 (SV40) early region, in particular, large T antigen (Tag), and the adenovirus oncoprotein E1A can rescue the tsBN67 cell proliferation defect at nonpermissive temperatures. The SV40 early region rescues the tsBN67 cell proliferation defect without restoring the HCF-1-chromatin association, indicating that these oncoproteins bypass a requirement for HCF-1 function. The SV40 early region also rescues the tsBN67 cytokinesis defect, suggesting that the roles of HCF-1 in cell proliferation and proper cytokinesis are intimately linked. The ability of SV40 Tag and adenovirus E1A to inactivate members of the pRb protein family-pRb, p107, and p130-is important for the bypass of HCF-1 function. These results suggest that HCF-1 regulates mammalian-cell proliferation and cytokinesis, at least in part, by either directly or indirectly opposing pRb family member function.
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Affiliation(s)
- Patrick T Reilly
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York 11724, USA
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