1
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Wang YC, Kelso AA, Karamafrooz A, Chen YH, Chen WK, Cheng CT, Qi Y, Gu L, Malkas L, Taglialatela A, Kung HJ, Moldovan GL, Ciccia A, Stark JM, Ann DK. Arginine shortage induces replication stress and confers genotoxic resistance by inhibiting histone H4 translation and promoting PCNA ubiquitination. Cell Rep 2023; 42:112296. [PMID: 36961817 PMCID: PMC10517088 DOI: 10.1016/j.celrep.2023.112296] [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: 09/20/2021] [Revised: 01/12/2023] [Accepted: 03/06/2023] [Indexed: 03/25/2023] Open
Abstract
The arginine dependency of cancer cells creates metabolic vulnerability. In this study, we examine the impact of arginine availability on DNA replication and genotoxicity resistance. Using DNA combing assays, we find that limiting extracellular arginine results in the arrest of cancer cells at S phase and a slowing or stalling of DNA replication. The translation of new histone H4 is arginine dependent and influences DNA replication. Increased proliferating cell nuclear antigen (PCNA) occupancy and helicase-like transcription factor (HLTF)-catalyzed PCNA K63-linked polyubiquitination protect arginine-starved cells from DNA damage. Arginine-deprived cancer cells display tolerance to genotoxicity in a PCNA K63-linked polyubiquitination-dependent manner. Our findings highlight the crucial role of extracellular arginine in nutrient-regulated DNA replication and provide potential avenues for the development of cancer treatments.
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Affiliation(s)
- Yi-Chang Wang
- Department of Diabetes Complications and Metabolism, Arthur Riggs Diabetes and Metabolism Research Institute, Beckman Research Institute, City of Hope, Duarte, CA 91010, USA
| | - Andrew A Kelso
- Irell & Manella Graduate School of Biological Sciences, City of Hope, Duarte, CA 91010, USA
| | - Adak Karamafrooz
- Department of Diabetes Complications and Metabolism, Arthur Riggs Diabetes and Metabolism Research Institute, Beckman Research Institute, City of Hope, Duarte, CA 91010, USA
| | - Yi-Hsuan Chen
- Department of Diabetes Complications and Metabolism, Arthur Riggs Diabetes and Metabolism Research Institute, Beckman Research Institute, City of Hope, Duarte, CA 91010, USA; Irell & Manella Graduate School of Biological Sciences, City of Hope, Duarte, CA 91010, USA
| | - Wei-Kai Chen
- Irell & Manella Graduate School of Biological Sciences, City of Hope, Duarte, CA 91010, USA
| | - Chun-Ting Cheng
- Department of Diabetes Complications and Metabolism, Arthur Riggs Diabetes and Metabolism Research Institute, Beckman Research Institute, City of Hope, Duarte, CA 91010, USA; Irell & Manella Graduate School of Biological Sciences, City of Hope, Duarte, CA 91010, USA
| | - Yue Qi
- Irell & Manella Graduate School of Biological Sciences, City of Hope, Duarte, CA 91010, USA
| | - Long Gu
- Department of Molecular and Cellular Biology, Beckman Research Institute, City of Hope, Duarte, CA 91010, USA
| | - Linda Malkas
- Department of Cancer Genetics and Epigenetics, Beckman Research Institute, City of Hope, Duarte, CA 91010, USA; Department of Molecular and Cellular Biology, Beckman Research Institute, City of Hope, Duarte, CA 91010, USA
| | - Angelo Taglialatela
- Department of Genetics and Development, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Hsing-Jien Kung
- Graduate Institute of Cancer Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University, Taipei 110, Taiwan, ROC
| | - George-Lucian Moldovan
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University College of Medicine, Hershey, PA 17033, USA
| | - Alberto Ciccia
- Department of Genetics and Development, Columbia University Irving Medical Center, New York, NY 10032, USA; Institute for Cancer Genetics, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Jeremy M Stark
- Department of Cancer Genetics and Epigenetics, Beckman Research Institute, City of Hope, Duarte, CA 91010, USA; Irell & Manella Graduate School of Biological Sciences, City of Hope, Duarte, CA 91010, USA
| | - David K Ann
- Department of Diabetes Complications and Metabolism, Arthur Riggs Diabetes and Metabolism Research Institute, Beckman Research Institute, City of Hope, Duarte, CA 91010, USA; Irell & Manella Graduate School of Biological Sciences, City of Hope, Duarte, CA 91010, USA.
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2
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Wang YC, Kelso AA, Karamafrooz A, Chen YH, Chen WK, Cheng CT, Qi Y, Gu L, Malkas L, Kung HJ, Moldovan GL, Ciccia A, Stark JM, Ann DK. Arginine shortage induces replication stress and confers genotoxic resistance by inhibiting histone H4 translation and promoting PCNA polyubiquitination. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.31.526362. [PMID: 36778247 PMCID: PMC9915598 DOI: 10.1101/2023.01.31.526362] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
The unique arginine dependencies of cancer cell proliferation and survival creates metabolic vulnerability. Here, we investigate the impact of extracellular arginine availability on DNA replication and genotoxic resistance. Using DNA combing assays, we find that when extracellular arginine is limited, cancer cells are arrested at S-phase and DNA replication forks slow or stall instantly until arginine is re-supplied. The translation of new histone H4 is arginine-dependent and impacts DNA replication and the expression of newly synthesized histone H4 is reduced in the avascular nutrient-poor breast cancer xenograft tumor cores. Furthermore, we demonstrate that increased PCNA occupancy and HLTF-catalyzed PCNA K63-linked polyubiquitination protects arginine-starved cells from hydroxyurea-induced, DNA2-catalyzed nascent strand degradation. Finally, arginine-deprived cancer cells are tolerant to genotoxic insults in a PCNA K63-linked polyubiquitination-dependent manner. Together, these findings reveal that extracellular arginine is the "linchpin" for nutrient-regulated DNA replication. Such information could be leveraged to expand current modalities or design new drug targets against cancer.
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Affiliation(s)
- Yi-Chang Wang
- Department of Diabetes Complications and Metabolism, Arthur Riggs Diabetes and Metabolism Research Institute, Beckman Research Institute, City of Hope, Duarte, CA 91010, USA
| | - Andrew A. Kelso
- Irell & Manella Graduate School of Biological Sciences, City of Hope, Duarte, CA 91010, USA
| | - Adak Karamafrooz
- Department of Diabetes Complications and Metabolism, Arthur Riggs Diabetes and Metabolism Research Institute, Beckman Research Institute, City of Hope, Duarte, CA 91010, USA
| | - Yi-Hsuan Chen
- Department of Diabetes Complications and Metabolism, Arthur Riggs Diabetes and Metabolism Research Institute, Beckman Research Institute, City of Hope, Duarte, CA 91010, USA
- Irell & Manella Graduate School of Biological Sciences, City of Hope, Duarte, CA 91010, USA
| | - Wei-Kai Chen
- Irell & Manella Graduate School of Biological Sciences, City of Hope, Duarte, CA 91010, USA
| | - Chun-Ting Cheng
- Department of Diabetes Complications and Metabolism, Arthur Riggs Diabetes and Metabolism Research Institute, Beckman Research Institute, City of Hope, Duarte, CA 91010, USA
- Irell & Manella Graduate School of Biological Sciences, City of Hope, Duarte, CA 91010, USA
| | - Yue Qi
- Irell & Manella Graduate School of Biological Sciences, City of Hope, Duarte, CA 91010, USA
| | - Long Gu
- Department of Molecular and Cellular Biology, Beckman Research Institute, City of Hope, Duarte, CA 91010, USA
| | - Linda Malkas
- Department of Cancer Genetics and Epigenetics, Beckman Research Institute, City of Hope, Duarte, CA 91010, USA
- Department of Molecular and Cellular Biology, Beckman Research Institute, City of Hope, Duarte, CA 91010, USA
| | - Hsing-Jien Kung
- Graduate Institute of Cancer Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University, Taipei 110, Taiwan, ROC
| | - George-Lucian Moldovan
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University College of Medicine, Hershey, PA 17033, USA
| | - Alberto Ciccia
- Department of Genetics and Development, Columbia University Medical Center, New York, NY 10032, USA
| | - Jeremy M. Stark
- Department of Cancer Genetics and Epigenetics, Beckman Research Institute, City of Hope, Duarte, CA 91010, USA
- Irell & Manella Graduate School of Biological Sciences, City of Hope, Duarte, CA 91010, USA
| | - David K Ann
- Department of Diabetes Complications and Metabolism, Arthur Riggs Diabetes and Metabolism Research Institute, Beckman Research Institute, City of Hope, Duarte, CA 91010, USA
- Irell & Manella Graduate School of Biological Sciences, City of Hope, Duarte, CA 91010, USA
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3
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Wang YL, Lee CC, Shen YC, Lin PL, Wu WR, Lin YZ, Cheng WC, Chang H, Hung Y, Cho YC, Liu LC, Xia WY, Ji JH, Liang JA, Chiang SF, Liu CG, Yao J, Hung MC, Wang SC. Evading immune surveillance via tyrosine phosphorylation of nuclear PCNA. Cell Rep 2021; 36:109537. [PMID: 34433039 DOI: 10.1016/j.celrep.2021.109537] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Revised: 03/26/2021] [Accepted: 07/26/2021] [Indexed: 12/23/2022] Open
Abstract
Increased DNA replication and metastasis are hallmarks of cancer progression, while deregulated proliferation often triggers sustained replication stresses in cancer cells. How cancer cells overcome the growth stress and proceed to metastasis remains largely elusive. Proliferating cell nuclear antigen (PCNA) is an indispensable component of the DNA replication machinery. Here, we show that phosphorylation of PCNA on tyrosine 211 (pY211-PCNA) regulates DNA metabolism and tumor microenvironment. Abrogation of pY211-PCNA blocks fork processivity, resulting in biogenesis of single-stranded DNA (ssDNA) through a MRE11-dependent mechanism. The cytosolic ssDNA subsequently induces inflammatory cytokines through a cyclic GMP-AMP synthetase (cGAS)-dependent cascade, triggering an anti-tumor immunity by natural killer (NK) cells to suppress distant metastasis. Expression of pY211-PCNA is inversely correlated with cytosolic ssDNA and associated with poor survival in patients with cancer. Our results pave the way to biomarkers and therapies exploiting immune responsiveness to target metastatic cancer.
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Affiliation(s)
- Yuan-Liang Wang
- Graduate Institute of Biomedical Sciences, College of Medicine, China Medical University, Taichung 40402, Taiwan
| | - Chuan-Chun Lee
- Center for Molecular Medicine, China Medical University Hospital, Taichung 40447, Taiwan
| | - Yi-Chun Shen
- Graduate Institute of Biomedical Sciences, College of Medicine, China Medical University, Taichung 40402, Taiwan
| | - Pei-Le Lin
- Graduate Institute of Biomedical Sciences, College of Medicine, China Medical University, Taichung 40402, Taiwan
| | - Wan-Rong Wu
- Graduate Institute of Biomedical Sciences, College of Medicine, China Medical University, Taichung 40402, Taiwan
| | - You-Zhe Lin
- Graduate Institute of Biomedical Sciences, College of Medicine, China Medical University, Taichung 40402, Taiwan
| | - Wei-Chung Cheng
- Graduate Institute of Biomedical Sciences, College of Medicine, China Medical University, Taichung 40402, Taiwan; Research Center for Tumor Medical Science, China Medical University, Taichung 40402, Taiwan; Cancer Biology and Drug Discovery Ph.D. Program, China Medical University, Taichung 40402, Taiwan
| | - Han Chang
- Division of Molecular Pathology, Department of Pathology, China Medical University Hospital, Taichung 40447, Taiwan
| | - Yu Hung
- Graduate Institute of Biomedical Sciences, College of Medicine, China Medical University, Taichung 40402, Taiwan
| | - Yi-Chun Cho
- Graduate Institute of Biomedical Sciences, College of Medicine, China Medical University, Taichung 40402, Taiwan
| | - Liang-Chih Liu
- Department of Surgery, China Medical University Hospital, Taichung 40447, Taiwan
| | - Wei-Ya Xia
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Jin-Huei Ji
- Department of Radiation Oncology, China Medical University Hospital, Taichung 40447, Taiwan
| | - Ji-An Liang
- School of Medicine, College of Medicine, China Medical University, Taichung 40402, Taiwan; Department of Radiation Oncology, China Medical University Hospital, Taichung 40447, Taiwan
| | - Shu-Fen Chiang
- Lab of Precision Medicine, Feng-Yuan Hospital, Ministry of Health and Welfare, Taichung, Taiwan
| | - Chang-Gong Liu
- Department of Experimental Therapeutics, The University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, USA
| | - Jun Yao
- Department of Neuro-Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Mien-Chie Hung
- Graduate Institute of Biomedical Sciences, College of Medicine, China Medical University, Taichung 40402, Taiwan; Center for Molecular Medicine, China Medical University Hospital, Taichung 40447, Taiwan; Research Center for Tumor Medical Science, China Medical University, Taichung 40402, Taiwan; Drug Development Center, China Medical University, Taichung 40402, Taiwan; Cancer Biology and Drug Discovery Ph.D. Program, China Medical University, Taichung 40402, Taiwan; Department of Biotechnology, Asia University, Taichung 41354, Taiwan.
| | - Shao-Chun Wang
- Graduate Institute of Biomedical Sciences, College of Medicine, China Medical University, Taichung 40402, Taiwan; Center for Molecular Medicine, China Medical University Hospital, Taichung 40447, Taiwan; Research Center for Tumor Medical Science, China Medical University, Taichung 40402, Taiwan; Drug Development Center, China Medical University, Taichung 40402, Taiwan; Cancer Biology and Drug Discovery Ph.D. Program, China Medical University, Taichung 40402, Taiwan; Department of Biotechnology, Asia University, Taichung 41354, Taiwan; Department of Cancer Biology, University of Cincinnati, Cincinnati, OH 45267, USA.
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4
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Gerits N, Johannessen M, Tümmler C, Walquist M, Kostenko S, Snapkov I, van Loon B, Ferrari E, Hübscher U, Moens U. Agnoprotein of polyomavirus BK interacts with proliferating cell nuclear antigen and inhibits DNA replication. Virol J 2015; 12:7. [PMID: 25638270 PMCID: PMC4318453 DOI: 10.1186/s12985-014-0220-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2014] [Accepted: 12/01/2014] [Indexed: 12/25/2022] Open
Abstract
Background The human polyomavirus BK expresses a 66 amino-acid peptide referred to as agnoprotein. Though mutants lacking agnoprotein are severely reduced in producing infectious virions, the exact function of this peptide remains incompletely understood. To elucidate the function of agnoprotein, we searched for novel cellular interaction partners. Methods Yeast-two hybrid assay was performed with agnoprotein as bait against human kidney and thymus libraries. The interaction between agnoprotein and putative partners was further examined by GST pull down, co-immunoprecipitation, and fluorescence resonance energy transfer studies. Biochemical and biological studies were performed to examine the functional implication of the interaction of agnoprotein with cellular target proteins. Results Proliferating cell nuclear antigen (PCNA), which acts as a processivity factor for DNA polymerase δ, was identified as an interaction partner. The interaction between agnoprotein and PCNA is direct and occurs also in human cells. Agnoprotein exerts an inhibitory effect on PCNA-dependent DNA synthesis in vitro and reduces cell proliferation when ectopically expressed. Overexpression of PCNA restores agnoprotein-mediated inhibition of cell proliferation. Conclusion Our data suggest that PCNA is a genuine interaction partner of agnoprotein and the inhibitory effect on PCNA-dependent DNA synthesis by the agnoprotein may play a role in switching off (viral) DNA replication late in the viral replication cycle when assembly of replicated genomes and synthesized viral capsid proteins occurs. Electronic supplementary material The online version of this article (doi:10.1186/s12985-014-0220-1) contains supplementary material, which is available to authorized users.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | - Ugo Moens
- UiT - The Arctic University of Norway, Faculty of Health Sciences, Department of Medical Biology, Molecular Inflammation Research Group, Tromsø NO-9037, Norway.
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5
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Wang SC. PCNA: a silent housekeeper or a potential therapeutic target? Trends Pharmacol Sci 2014; 35:178-86. [PMID: 24655521 DOI: 10.1016/j.tips.2014.02.004] [Citation(s) in RCA: 202] [Impact Index Per Article: 20.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2013] [Revised: 02/17/2014] [Accepted: 02/18/2014] [Indexed: 11/18/2022]
Abstract
Proliferating cell nuclear antigen (PCNA) is known as a molecular marker for proliferation given its role in replication. Three identical molecules of PCNA form a molecular sliding clamp around the DNA double helix. This provides an essential platform on which multiple proteins are dynamically recruited and coordinately regulated. Over the past decade, new research has provided a deeper comprehension of PCNA as a coordinator of essential cellular functions for cell growth, death, and maintenance. Although the biology of PCNA in proliferation has been comprehensively reviewed, research progress in unveiling the potential of targeting PCNA for disease treatment has not been systematically discussed. Here we briefly summarize the basic structural and functional characteristics of PCNA, and then discuss new developments in its protein interactions, trimer formation, and signaling regulation that open the door to possible therapeutic targeting of PCNA.
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Affiliation(s)
- Shao-Chun Wang
- Department of Cancer Biology, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA.
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Lentz S, Eversole R, Means J. Screening of Biomarkers for the Histological Examination of Cellular Proliferation and Death in the Livers of the Western MosquitofishGambusia Affinis. J Histotechnol 2013. [DOI: 10.1179/his.2003.26.3.157] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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Zhao H, Chen MS, Lo YH, Waltz SE, Wang J, Ho PC, Vasiliauskas J, Plattner R, Wang YL, Wang SC. The Ron receptor tyrosine kinase activates c-Abl to promote cell proliferation through tyrosine phosphorylation of PCNA in breast cancer. Oncogene 2013; 33:1429-37. [PMID: 23542172 DOI: 10.1038/onc.2013.84] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2012] [Revised: 12/12/2012] [Accepted: 01/11/2013] [Indexed: 12/14/2022]
Abstract
Multiple growth pathways lead to enhanced proliferation in malignant cells. However, how the core machinery of DNA replication is regulated by growth signaling remains largely unclear. The sliding clamp proliferating cell nuclear antigen (PCNA) is an indispensable component of the DNA machinery responsible for replicating the genome and maintaining genomic integrity. We previously reported that epidermal growth factor receptor (EGFR) triggered tyrosine 211 (Y211) phosphorylation of PCNA, which in turn stabilized PCNA on chromatin to promote cell proliferation. Here we show that the phosphorylation can also be catalyzed by the non-receptor tyrosine kinase c-Abl. We further demonstrate that, in the absence of EGFR, signaling to PCNA can be attained through the activation of the Ron receptor tyrosine kinase and the downstream non-receptor tyrosine kinase c-Abl. We show that Ron and c-Abl form a complex, and that activation of Ron by its ligand, hepatocyte growth factor-like protein (HGFL), stimulates c-Abl kinase activity, which in turn directly phosphorylates PCNA at Y211 and leads to an increased level of chromatin-associated PCNA. Correspondingly, HGFL-induced Ron activation resulted in Y211 phosphorylation of PCNA while silencing of c-Abl blocked this effect. We show that c-Abl and Y211 phosphorylation of PCNA is an important axis downstream of Ron, which is required for cell proliferation. Treatment with a specific peptide that inhibits Y211 phosphorylation of PCNA or with the c-Abl pharmacological inhibitor imatinib suppressed HGFL-induced cell proliferation. Our findings identify the pathway of Ron-c-Abl-PCNA as a mechanism of oncogene-induced cell proliferation, with potentially important implications for development of combination therapy of breast cancer.
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Affiliation(s)
- H Zhao
- Department of Cancer Biology, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - M-S Chen
- Department of Cancer Biology, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Y-H Lo
- Department of Cancer Biology, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - S E Waltz
- 1] Department of Cancer Biology, University of Cincinnati College of Medicine, Cincinnati, OH, USA [2] Cincinnati Veterans Affairs Medical Center, Cincinnati, OH, USA
| | - J Wang
- Department of Pathology and Laboratory Medicine, University of Cincinnati Medical Center, Cincinnati, OH, USA
| | - P-C Ho
- Department of Cancer Biology, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - J Vasiliauskas
- Department of Cancer Biology, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - R Plattner
- Department of Molecular and Biomedical Pharmacology, University of Kentucky School of Medicine, Lexington, KY, USA
| | - Y-L Wang
- Department of Cancer Biology, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - S-C Wang
- Department of Cancer Biology, University of Cincinnati College of Medicine, Cincinnati, OH, USA
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8
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Lo YH, Ho PC, Chen MS, Hugo E, Ben-Jonathan N, Wang SC. Phosphorylation at tyrosine 114 of Proliferating Cell Nuclear Antigen (PCNA) is required for adipogenesis in response to high fat diet. Biochem Biophys Res Commun 2013; 430:43-8. [PMID: 23201573 PMCID: PMC3724334 DOI: 10.1016/j.bbrc.2012.11.047] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2012] [Accepted: 11/06/2012] [Indexed: 11/25/2022]
Abstract
Clonal proliferation is an obligatory component of adipogenesis. Although several cell cycle regulators are known to participate in the transition between pre-adipocyte proliferation and terminal adipocyte differentiation, how the core DNA synthesis machinery is coordinately regulated in adipogenesis remains elusive. PCNA (Proliferating Cell Nuclear Antigen) is an indispensable component for DNA synthesis during proliferation. Here we show that PCNA is subject to phosphorylation at the highly conserved tyrosine residue 114 (Y114). Replacing the Y114 residue with phenylalanine (Y114F), which is structurally similar to tyrosine but cannot be phosphorylated, does not affect normal animal development. However, when challenged with high fat diet, mice carrying homozygous Y114F alleles (PCNA(F/F)) are resistant to adipose tissue enlargement in comparison to wild-type (WT) mice. Mouse embryonic fibroblasts (MEFs) harboring WT or Y114F mutant PCNA proliferate at similar rates. However, when subjected to adipogenesis induction in culture, PCNA(F/F) MEFs are not able to re-enter the cell cycle and fail to form mature adipocytes, while WT MEFs undergo mitotic clonal expansion in response to the adipogenic stimulation, accompanied by enhanced Y114 phosphorylation of PCNA, and differentiate to mature adipocytes. Consistent with the function of Y114 phosphorylation in clonal proliferation in adipogenesis, fat tissues isolated from WT mice contain significantly more adipocytes than those isolated from PCNA(F/F) mice. This study identifies a critical role for PCNA in adipose tissue development, and for the first time identifies a role of the core DNA replication machinery at the interface between proliferation and differentiation.
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Affiliation(s)
- Yuan-Hung Lo
- Department of Cancer Biology, University of Cincinnati College of Medicine, 3125 Eden Avenue, Cincinnati, OH 45267-0521, USA
- Department of Environmental Health, University of Cincinnati College of Medicine, 3223 Eden Avenue, Kettering Laboratory, Cincinnati, OH 45267-0056
| | - Po-Chun Ho
- Department of Cancer Biology, University of Cincinnati College of Medicine, 3125 Eden Avenue, Cincinnati, OH 45267-0521, USA
- Department of Environmental Health, University of Cincinnati College of Medicine, 3223 Eden Avenue, Kettering Laboratory, Cincinnati, OH 45267-0056
| | - Min-Shan Chen
- Department of Cancer Biology, University of Cincinnati College of Medicine, 3125 Eden Avenue, Cincinnati, OH 45267-0521, USA
- Department of Environmental Health, University of Cincinnati College of Medicine, 3223 Eden Avenue, Kettering Laboratory, Cincinnati, OH 45267-0056
| | - Eric Hugo
- Department of Cancer Biology, University of Cincinnati College of Medicine, 3125 Eden Avenue, Cincinnati, OH 45267-0521, USA
- Department of Environmental Health, University of Cincinnati College of Medicine, 3223 Eden Avenue, Kettering Laboratory, Cincinnati, OH 45267-0056
| | - Nira Ben-Jonathan
- Department of Cancer Biology, University of Cincinnati College of Medicine, 3125 Eden Avenue, Cincinnati, OH 45267-0521, USA
- Department of Environmental Health, University of Cincinnati College of Medicine, 3223 Eden Avenue, Kettering Laboratory, Cincinnati, OH 45267-0056
| | - Shao-Chun Wang
- Address correspondence to: Shao-Chun Wang, Ph.D. Department of Cancer Biology, University of Cincinnati College of Medicine, 3125 Eden Avenue, The Vontz Center, Cincinnati, OH, 45267-0521. Tel; 513-558-4259; Fax: 513-558-4454;
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9
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De Biasio A, Blanco FJ. Proliferating Cell Nuclear Antigen Structure and Interactions. PROTEIN-NUCLEIC ACIDS INTERACTIONS 2013; 91:1-36. [DOI: 10.1016/b978-0-12-411637-5.00001-9] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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10
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Zhao H, Ho PC, Lo YH, Espejo A, Bedford MT, Hung MC, Wang SC. Interaction of proliferation cell nuclear antigen (PCNA) with c-Abl in cell proliferation and response to DNA damages in breast cancer. PLoS One 2012; 7:e29416. [PMID: 22238610 PMCID: PMC3251568 DOI: 10.1371/journal.pone.0029416] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2011] [Accepted: 11/28/2011] [Indexed: 01/09/2023] Open
Abstract
Cell proliferation in primary and metastatic tumors is a fundamental characteristic of advanced breast cancer. Further understanding of the mechanism underlying enhanced cell growth will be important in identifying novel prognostic markers and therapeutic targets. Here we demonstrated that tyrosine phosphorylation of the proliferating cell nuclear antigen (PCNA) is a critical event in growth regulation of breast cancer cells. We found that phosphorylation of PCNA at tyrosine 211 (Y211) enhanced its association with the non-receptor tyrosine kinase c-Abl. We further demonstrated that c-Abl facilitates chromatin association of PCNA and is required for nuclear foci formation of PCNA in cells stressed by DNA damage as well as in unperturbed cells. Targeting Y211 phosphorylation of PCNA with a cell-permeable peptide inhibited the phosphorylation and reduced the PCNA-Abl interaction. These results show that PCNA signal transduction has an important impact on the growth regulation of breast cancer cells.
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Affiliation(s)
- Huajun Zhao
- Department of Cancer and Cell Biology, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America
| | - Po-Chun Ho
- Department of Cancer and Cell Biology, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America
| | - Yuan-Hung Lo
- Department of Cancer and Cell Biology, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America
| | - Alexsandra Espejo
- Department of Molecular Carcinogenesis, M. D. Anderson Cancer Center, University of Texas, Smithville, Texas, United States of America
| | - Mark T. Bedford
- Department of Molecular Carcinogenesis, M. D. Anderson Cancer Center, University of Texas, Smithville, Texas, United States of America
| | - Mien-Chie Hung
- Department of Molecular and Cellular Oncology, M. D. Anderson Cancer Center, University of Texas, Houston, Texas, United States of America
- Center for Molecular Medicine, China Medical University and Hospital, Taichung, Taiwan
- Graduate Institute of Cancer Biology, China Medical University and Hospital, Taichung, Taiwan
| | - Shao-Chun Wang
- Department of Cancer and Cell Biology, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America
- * E-mail: .
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11
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Zhao H, Lo YH, Ma L, Waltz SE, Gray JK, Hung MC, Wang SC. Targeting tyrosine phosphorylation of PCNA inhibits prostate cancer growth. Mol Cancer Ther 2011; 10:29-36. [PMID: 21220489 DOI: 10.1158/1535-7163.mct-10-0778] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The proliferation cell nuclear antigen (PCNA) is a critical protein required for DNA replication in proliferating cells including cancer cells. However, direct inhibition of PCNA in cancer cells has been difficult due to the lack of targetable sites. We previously reported that phosphorylation of tyrosine 211 (Y211) on PCNA is important for the proliferative function of PCNA when this protein is associated with the chromatin in cancer cells. Here, we show that the Y211 phosphorylation of PCNA is a frequent event in advanced prostate cancer. To explore the potential of this signaling event in inhibition of cancer cell growth, we used a synthetic peptide, the Y211F peptide, which when present inhibits phosphorylation of Y211 on endogenous PCNA. Treatment with this peptide, but not a scrambled control peptide, resulted in S-phase arrest, inhibition of DNA synthesis, and enhanced cell death in a panel of human prostate cancer cell lines. In addition, treatment with the Y211F peptide led to decreased tumor growth in PC3-derived xenograft tumors in vivo in nude mice. Our study shows for the first time that PCNA phosphorylation at Y211 is a frequent and biologically important signaling event in prostate cancer. This study also shows a proof of concept that Y211 phosphorylation of PCNA may be used as a therapeutic target in prostate cancer cells, including cells of advanced cancers that are refractory to standard hormonal therapies.
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Affiliation(s)
- Huajun Zhao
- Corresponding Author: Shao-Chun Wang, Department of Cancer and Cell Biology, 3125 Eden Ave., Cincinnati, OH 45267, USA
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Sabbioneda S, Minesinger BK, Giannattasio M, Plevani P, Muzi-Falconi M, Jinks-Robertson S. The 9-1-1 checkpoint clamp physically interacts with polzeta and is partially required for spontaneous polzeta-dependent mutagenesis in Saccharomyces cerevisiae. J Biol Chem 2005; 280:38657-65. [PMID: 16169844 DOI: 10.1074/jbc.m507638200] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
The use of translesion synthesis (TLS) polymerases to bypass DNA lesions during replication constitutes an important mechanism to restart blocked/stalled DNA replication forks. Because TLS polymerases generally have low fidelity on undamaged DNA, the cell must regulate the interaction of TLS polymerases with damaged versus undamaged DNA to maintain genome integrity. The Saccharomyces cerevisiae checkpoint proteins Ddc1, Rad17, and Mec3 form a clamp-like structure (the 9-1-1 clamp) that has physical similarity to the homotrimeric sliding clamp proliferating cell nuclear antigen, which interacts with and promotes the processivity of the replicative DNA polymerases. In this work, we demonstrate both an in vivo and in vitro physical interaction between the Mec3 and Ddc1 subunits of the 9-1-1 clamp and the Rev7 subunit of the Polzeta TLS polymerase. In addition, we demonstrate that loss of Mec3, Ddc1, or Rad17 results in a decrease in Polzeta-dependent spontaneous mutagenesis. These results suggest that, in addition to its checkpoint signaling role, the 9-1-1 clamp may physically regulate Polzeta-dependent mutagenesis by controlling the access of Polzeta to damaged DNA.
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Affiliation(s)
- Simone Sabbioneda
- Dipartimento di Scienze Biomolecolari e Biotecnologie, Università degli Studi di Milano, Milano, Italy 20133
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13
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Bao S, Lu T, Wang X, Zheng H, Wang LE, Wei Q, Hittelman WN, Li L. Disruption of the Rad9/Rad1/Hus1 (9–1–1) complex leads to checkpoint signaling and replication defects. Oncogene 2004; 23:5586-93. [PMID: 15184880 DOI: 10.1038/sj.onc.1207753] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The checkpoint sliding-clamp complex, Rad9/Rad1/Hus1, plays a critical role during initiation of checkpoint signals in response to DNA damage and replication disruption. We investigated the impact of loss of Rad1 on checkpoint function and on DNA replication in mammalian cells. We show that RAD1 is an essential gene for sustained cell proliferation and that loss of Rad1 causes destabilization of Rad9 and Hus1 and consequently disintegration of the sliding-clamp complex. In Rad1-depleted cells, Atr-dependent Chk1 activation was impaired whereas Atm-mediated Chk2 activation was unaffected, suggesting that the sliding clamp is required primarily in Atr-dependent signal activation. Disruption of sliding-clamp function also caused a major defect in S-phase control. Rad1-depleted cells exhibited an RDS phenotype, indicating that damage-induced S-phase arrest was compromised by Rad1 loss. Furthermore, lack of Rad1 also affected the efficiency of replication recovery from DNA synthesis blockage, resulting in a prolonged S phase. These deficiencies may perpetually generate DNA strand breakage as we have found chromosomal abnormalities in Rad1-depleted cells. We conclude that the Rad9/Rad1/Hus1 complex is essential for Atr-dependent checkpoint signaling, which may play critical roles in the facilitation of DNA replication and in the maintenance of genomic integrity.
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Affiliation(s)
- Shilai Bao
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
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14
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Wang X, Guan J, Hu B, Weiss RS, Iliakis G, Wang Y. Involvement of Hus1 in the chain elongation step of DNA replication after exposure to camptothecin or ionizing radiation. Nucleic Acids Res 2004; 32:767-75. [PMID: 14762204 PMCID: PMC373359 DOI: 10.1093/nar/gkh243] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2003] [Revised: 12/23/2003] [Accepted: 12/23/2003] [Indexed: 11/12/2022] Open
Abstract
DNA damage-induced S phase (S) checkpoint includes inhibition of both replicon initiation and chain elongation. The precise mechanism for controlling the two processes remains unclear. In this study, we showed that Hus1-deficient mouse cells had an impaired S checkpoint after exposure to DNA strand break-inducing agents such as camptothecin (CPT) (>or=1.0 micro M), or ionizing radiation (IR) (>or=15 Gy). The Hus1-dependent S checkpoint contributes to cell resistance to CPT. This impaired S checkpoint induced by CPT or IR in Hus1-deficient cells reflected mainly the chain elongation step of DNA replication and was correlated with the reduction of dissociation of PCNA from DNA replication foci. Although Hus1 is required for Rad9 phosphorylation following exposure of cells to CPT or IR, Hus1-deficient cells showed normal activation of ATR/CHK1 and ATM kinases at doses where the checkpoint defects were manifested, suggesting that Hus1 is not a component of the sensor system for activating these pathways in S checkpoint induced by CPT or IR.
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Affiliation(s)
- Xiang Wang
- Department of Radiation Oncology, Kimmel Cancer Center of Jefferson Medical College, Thomas Jefferson University, Philadelphia, PA 19107, USA
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15
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Abstract
The human genome, comprising three billion base pairs coding for 30000-40000 genes, is constantly attacked by endogenous reactive metabolites, therapeutic drugs and a plethora of environmental mutagens that impact its integrity. Thus it is obvious that the stability of the genome must be under continuous surveillance. This is accomplished by DNA repair mechanisms, which have evolved to remove or to tolerate pre-cytotoxic, pre-mutagenic and pre-clastogenic DNA lesions in an error-free, or in some cases, error-prone way. Defects in DNA repair give rise to hypersensitivity to DNA-damaging agents, accumulation of mutations in the genome and finally to the development of cancer and various metabolic disorders. The importance of DNA repair is illustrated by DNA repair deficiency and genomic instability syndromes, which are characterised by increased cancer incidence and multiple metabolic alterations. Up to 130 genes have been identified in humans that are associated with DNA repair. This review is aimed at updating our current knowledge of the various repair pathways by providing an overview of DNA-repair genes and the corresponding proteins, participating either directly in DNA repair, or in checkpoint control and signaling of DNA damage.
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Affiliation(s)
- Markus Christmann
- Division of Applied Toxicology, Institute of Toxicology, University of Mainz, Obere Zahlbacher Str. 67, D-55131 Mainz, Germany
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16
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Post SM, Tomkinson AE, Lee EYHP. The human checkpoint Rad protein Rad17 is chromatin-associated throughout the cell cycle, localizes to DNA replication sites, and interacts with DNA polymerase epsilon. Nucleic Acids Res 2003; 31:5568-75. [PMID: 14500819 PMCID: PMC206465 DOI: 10.1093/nar/gkg765] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The checkpoint Rad proteins Rad17, Rad9, Rad1, Hus1, ATR, and ATRIP become associated with chromatin in response to DNA damage caused by genotoxic agents and replication inhibitors, as well as during unperturbed DNA replication in S phase. Here we show that murine Rad17 is phosphorylated at two sites that were previously shown to be modified in response to DNA damage, independent of DNA damage and ATM, in proliferating tissue. In contrast to studies with Xenopus laevis extracts but similar to observations in Schizosaccharomyces pombe, the level of chromatin-bound hRad17 remains relatively constant during the cell cycle and does not change significantly in response to DNA damage or replication block. However, phosphorylated hRad17 preferentially associates with the sites of ongoing DNA replication and interacts with the DNA replication protein, DNA polymerase epsilon. These results provide a link between the DNA damage checkpoint machinery and the replication apparatus and suggest that hRad17 may play a role in monitoring the progress of DNA replication via its interaction with DNA polymerase epsilon.
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Affiliation(s)
- Sean M Post
- Department of Molecular Medicine/Institute of Biotechnology, University of Texas Health Science Center at San Antonio, 15355 Lambda Drive, San Antonio, TX 78245, USA
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17
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Meister P, Poidevin M, Francesconi S, Tratner I, Zarzov P, Baldacci G. Nuclear factories for signalling and repairing DNA double strand breaks in living fission yeast. Nucleic Acids Res 2003; 31:5064-73. [PMID: 12930957 PMCID: PMC212815 DOI: 10.1093/nar/gkg719] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
In mammalian and budding yeast cells treated with genotoxic agents, different proteins implicated in detecting, signalling or repairing DNA lesions form nuclear foci. We studied foci formed by proteins involved in these processes in living fission yeast cells, which is amenable to genetic and molecular analysis. Using fluorescent tags, we analysed subnuclear localisations of the DNA damage checkpoint protein Rad9, of the homologous recombination protein Rad22 and of PCNA, which are implicated in many aspects of DNA metabolism. After inducing double strand breaks (DSBs) with ionising radiations, Rad22, Rad9 and PCNA form a low number of nuclear foci. Rad9 recruitment to foci depends on the presence of Rad1, Hus1 and Rad17, but is independent of downstream checkpoint effectors and of homologous recombination proteins. Likewise, Rad22 and PCNA form foci despite inactive homologous recombination repair and impaired DNA damage checkpoint. Rad22 and Rad9 foci co-localise completely, whereas PCNA co-localises with Rad22 and Rad9 only partially. Foci do not disassemble in cells unable to repair DNA by homologous recombination. Thus, in fission yeast, DSBs are detected by the DNA damage checkpoint and are repaired by homologous recombination at a few spatially confined subnuclear compartments where Rad22, Rad9 and PCNA concentrate independently.
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Affiliation(s)
- Peter Meister
- Institut Curie-CNRS UMR 2027, Bâtiment 110, Centre Universitaire, 91405 Orsay Cedex, France
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18
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Yamamoto T, Kimura S, Mori Y, Uchiyama Y, Ishibashi T, Hashimoto J, Sakaguchi K. Interaction between proliferating cell nuclear antigen and JUN-activation-domain-binding protein 1 in the meristem of rice, Oryza sativa L. PLANTA 2003; 217:175-183. [PMID: 12783325 DOI: 10.1007/s00425-003-0981-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2002] [Accepted: 12/30/2002] [Indexed: 05/24/2023]
Abstract
The eukaryotic polymerase processivity factor, proliferating cell nuclear antigen (PCNA), interacts with many cell cycle-regulator proteins and with proteins involved in the mechanisms of DNA replication and repair. In the present study using two-hybrid analysis with PCNA from rice, Oryza sativa L. cv. Nipponbare (OsPCNA), we found that OsPCNA interacted in vitro and in vivo with rice JUN-activation-domain-binding protein 1 (OsJab1), which is known as COP9/signalsome subunit 5. Both OsPCNA and OsJab1 transcripts were expressed strongly in the shoot apical meristem and weakly in young leaves, flag leaves, ears, roots and root tips. No expression was detected in the mature leaves. The OsPCNA and OsJab1 proteins were expressed and accumulated mostly in the shoot apical meristem and ears, suggesting that OsJab1 is involved in cell proliferation in cooperation with OsPCNA. The role of OsPCNA with OsJab1 in plant DNA proliferation is discussed.
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Affiliation(s)
- Taichi Yamamoto
- Department of Applied Biological Science, Faculty of Science and Technology, Science University of Tokyo, 2641 Yamazaki, Noda-shi, 278-8510, Chiba-ken, Japan
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19
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Dahm K, Hübscher U. Colocalization of human Rad17 and PCNA in late S phase of the cell cycle upon replication block. Oncogene 2002; 21:7710-9. [PMID: 12400013 DOI: 10.1038/sj.onc.1205872] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2002] [Revised: 07/11/2002] [Accepted: 07/15/2002] [Indexed: 12/22/2022]
Abstract
In response to replication block or DNA damage in S phase the DNA replication and DNA damage checkpoints are activated. The current model in human predicts, that a Rad17/Replication factor C (RF-C) complex might serve as a recruitment complex for the Rad9/Hus1/Rad1 complex to sites of replication block or DNA damage. In this study we have investigated the fate of the Rad17/RF-C complex after treatment of synchronized Hela cells with the replication inhibitor hydroxyurea. In hydroxyurea treated cells the RF-C p37 subunit became more resistant to extraction. Moreover, co-immunoprecipitation studies with extracts of hydroxyurea treated cells showed an interaction of RF-C p37 with Rad17 and of PCNA with Rad9 and RF-C p37. An enhanced colocalization of Rad17 and PCNA in late S phase after hydroxyurea treatment was observed. Our data suggested, that upon replication block a Rad17/RF-C complex is recruited to sites of DNA lesions in late S phase, binds the Rad9/Hus1/Rad1 complex and enables it to interact with PCNA. An interaction of Rad17/RF-C with PCNA appears to be mediated by the small RF-C p37 subunit, suggesting that PCNA might provide communication between replication checkpoint control and DNA replication and repair.
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Affiliation(s)
- Kirsten Dahm
- Institute of Veterinary Biochemistry and Molecular Biology, University Zürich-Irchel, Winterthurerstrasse 190, 8057 Zürich, Switzerland
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20
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Hirai I, Wang HG. A role of the C-terminal region of human Rad9 (hRad9) in nuclear transport of the hRad9 checkpoint complex. J Biol Chem 2002; 277:25722-7. [PMID: 11994305 DOI: 10.1074/jbc.m203079200] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Rad9, Rad1, and Hus1 are members of the Rad family of checkpoint proteins that are required for both DNA replication and DNA damage checkpoints and are thought to function as sensors in the DNA integrity checkpoint control. These proteins can interact with each other and form a stable proliferating cell nuclear antigen-related Rad9.Rad1.Hus1 heterotrimeric complex that might encircle DNA at or near the damaged sites. In this study, we demonstrate that the human Rad9 (hRad9) protein contains a predicted nuclear localization sequence (NLS) near its C terminus, which plays an essential role in the hRad9-mediated G(2) checkpoint. Deletion experiments indicate that the NLS-containing region of hRad9 is critical for the nuclear transport of not only hRad9 but also human Rad1 (hRad1) and human Hus1 (hHus1), although this region is not required for hRad9.hRad1.hHus1 complex formation. In support of the role that hRad9 NLS plays in the nuclear targeting of the hRad9.hRad1.hHus1 complex, overexpression of a deletion mutant of hRad9 lacking the NLS-containing C-terminal region can bypass the G(2) checkpoint and result in cell death after ionizing radiation or hydroxyurea treatment. Moreover, knockdown of hRad9 expression by small interfering RNA (siRNA) results in hRad1 accumulation in the cytoplasm and significantly abrogates the G(2) checkpoint in the presence of damaged DNA or incomplete DNA replication. Thus, the C-terminal region of human Rad9 protein is important for G(2) checkpoint control by operating the transport of the hRad9.hRad1.hHus1 checkpoint complex into the nucleus.
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Affiliation(s)
- Itaru Hirai
- Drug Discovery Program, H. Lee Moffitt Cancer Center and Research Institute, Tampa, Florida 33612, USA
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21
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Yoshida K, Komatsu K, Wang HG, Kufe D. c-Abl tyrosine kinase regulates the human Rad9 checkpoint protein in response to DNA damage. Mol Cell Biol 2002; 22:3292-300. [PMID: 11971963 PMCID: PMC133797 DOI: 10.1128/mcb.22.10.3292-3300.2002] [Citation(s) in RCA: 80] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The ubiquitously expressed c-Abl tyrosine kinase is activated in the apoptotic response of cells to DNA damage. The mechanisms by which c-Abl signals the induction of apoptosis are not understood. Here we show that c-Abl binds constitutively to the mammalian homolog of the Schizosaccharomyces pombe Rad9 cell cycle checkpoint protein. The SH3 domain of c-Abl interacts directly with the C-terminal region of Rad9. c-Abl phosphorylates the Rad9 Bcl-2 homology 3 domain (Tyr-28) in vitro and in cells exposed to DNA-damaging agents. The results also demonstrate that c-Abl-mediated phosphorylation of Rad9 induces binding of Rad9 to the antiapototic Bcl-x(L) protein. The regulation of Rad9 by c-Abl in the DNA damage response is further supported by the demonstration that the interaction between c-Abl and Rad9 contributes to DNA damage-induced apoptosis. These findings indicate that Rad9 is regulated by a c-Abl-dependent mechanism in the apoptotic response to genotoxic stress.
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Affiliation(s)
- Kiyotsugu Yoshida
- Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts 02115, USA
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22
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Sever-Chroneos Z, Angus SP, Fribourg AF, Wan H, Todorov I, Knudsen KE, Knudsen ES. Retinoblastoma tumor suppressor protein signals through inhibition of cyclin-dependent kinase 2 activity to disrupt PCNA function in S phase. Mol Cell Biol 2001; 21:4032-45. [PMID: 11359910 PMCID: PMC87065 DOI: 10.1128/mcb.21.12.4032-4045.2001] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2000] [Accepted: 03/13/2001] [Indexed: 11/20/2022] Open
Abstract
The retinoblastoma tumor suppressor protein (RB) is a negative regulator of the cell cycle that inhibits both G(1) and S-phase progression. While RB-mediated G(1) inhibition has been extensively studied, the mechanism utilized for S-phase inhibition is unknown. To delineate the mechanism through which RB inhibits DNA replication, we generated cells which inducibly express a constitutively active allele of RB (PSM-RB). We show that RB-mediated S-phase inhibition does not inhibit the chromatin binding function of MCM2 or RPA, suggesting that RB does not regulate the prereplication complex or disrupt early initiation events. However, activation of RB in S-phase cells disrupts the chromatin tethering of PCNA, a requisite component of the DNA replication machinery. The action of RB was S phase specific and did not inhibit the DNA damage-mediated association of PCNA with chromatin. We also show that RB-mediated PCNA inhibition was dependent on downregulation of CDK2 activity, which was achieved through the downregulation of cyclin A. Importantly, restoration of cyclin-dependent kinase 2 (CDK2)-cyclin A and thus PCNA activity partially restored S-phase progression in the presence of active RB. Therefore, the data presented identify RB-mediated regulation of PCNA activity via CDK2 attenuation as a mechanism through which RB regulates S-phase progression. Together, these findings identify a novel pathway of RB-mediated replication inhibition.
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Affiliation(s)
- Z Sever-Chroneos
- Department of Cell Biology, Vontz Center for Molecular Studies, University of Cincinnati, College of Medicine, Cincinnati, Ohio 45267-0521, USA
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