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Arakawa J, Kondoh H, Matsushita T, Ogino Y, Asai M, Tanuma SI, Uchiumi F. Induction of the human CDC45 gene promoter activity by natural compound trans‑resveratrol. Mol Med Rep 2024; 29:92. [PMID: 38577929 PMCID: PMC11025027 DOI: 10.3892/mmr.2024.13216] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Accepted: 03/13/2024] [Indexed: 04/06/2024] Open
Abstract
GGAA motifs in the human TP53 and HELB gene promoters play a part in responding to trans‑resveratrol (Rsv) in HeLa S3 cells. This sequence is also present in the 5'‑upstream region of the human CDC45 gene, which encodes a component of CMG DNA helicase protein complex. The cells were treated with Rsv (20 µM), then transcripts and the translated protein were analyzed by quantitative RT‑PCR and western blotting, respectively. The results showed that the CDC45 gene and protein expression levels were induced after the treatment. To examine whether they were due to the activation of transcription, a 5'‑upstream 556‑bp of the CDC45 gene was cloned and inserted into a multi‑cloning site of the Luciferase (Luc) expression vector. In the present study, various deletion/point mutation‑introduced Luc expression plasmids were constructed and they were used for the transient transfection assay. The results showed that the GGAA motif, which is included in a putative RELB protein recognizing sequence, plays a part in the promoter activity with response to Rsv in HeLa S3 cells.
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Affiliation(s)
- Jun Arakawa
- Department of Gene Regulation, Faculty of Pharmaceutical Sciences, Tokyo University of Science, Noda, Chiba 278-8510, Japan
| | - Hikaru Kondoh
- Department of Gene Regulation, Faculty of Pharmaceutical Sciences, Tokyo University of Science, Noda, Chiba 278-8510, Japan
| | - Tokiyoshi Matsushita
- Department of Gene Regulation, Faculty of Pharmaceutical Sciences, Tokyo University of Science, Noda, Chiba 278-8510, Japan
| | - Yoko Ogino
- Department of Gene Regulation, Faculty of Pharmaceutical Sciences, Tokyo University of Science, Noda, Chiba 278-8510, Japan
| | - Masashi Asai
- Department of Gene Regulation, Faculty of Pharmaceutical Sciences, Tokyo University of Science, Noda, Chiba 278-8510, Japan
- Laboratory of Kampo Pharmacology, Faculty of Pharmaceutical Sciences, Yokohama University of Pharmacy, Yokohama, Kanagawa 245-0066, Japan
| | - Sei-Ichi Tanuma
- Genomic Medicinal Science, Research Institute for Science and Technology, Tokyo University of Science, Noda, Chiba 278-8510, Japan
| | - Fumiaki Uchiumi
- Department of Gene Regulation, Faculty of Pharmaceutical Sciences, Tokyo University of Science, Noda, Chiba 278-8510, Japan
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2
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Wu L, Gao G, Mi H, Luo Z, Wang Z, Liu Y, Wu L, Long H, Shen Y. Validation of CDC45 as a novel biomarker for diagnosis and prognosis of gastric cancer. PeerJ 2024; 12:e17130. [PMID: 38515458 PMCID: PMC10956518 DOI: 10.7717/peerj.17130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Accepted: 02/27/2024] [Indexed: 03/23/2024] Open
Abstract
Background Cell division cycle protein 45 (CDC45) has been demonstrated to play vital roles in the progression of various malignancies. However, the clinical significance of CDC45 in gastric cancer (GC) remains unreported. Method In this study, we employed the TCGA database and the TCGA & GTEx dataset to compare the mRNA expression levels of CDC45 between gastric cancer tissues and adjacent or normal tissues (p < 0.05 was considered statistically significant), which was further validated in multiple datasets including GSE13911, GSE29272, GSE118916, GSE66229, as well as RT-qPCR. Furthermore, we harnessed the Human Protein Atlas (HPA) to evaluate the protein expression of CDC45, which was subsequently verified through immunohistochemistry (IHC). To ascertain the diagnostic utility of CDC45, receiver operating characteristic (ROC) curves and the area under the ROC curve (AUC) were calculated in TCGA database, and further validated it in TCGA & GTEx and GSE66229 datasets. The Kaplan-Meier method was used to reveal the prognostic importance of CDC45 in The Cancer Genome Atlas (TCGA) database and authenticated through the GSE66229, GSE84433, and GSE84437 datasets. Through cBioPortal, we identified co-expressed genes of CDC45, and pursued enrichment analysis. Additionally, we availed gene set enrichment analysis (GSEA) to annotate the biological functions of CDC45. Results Differential expression analysis revealed that CDC45 was significantly upregulated at both the mRNA and protein levels in GC (all p < 0.05). Remarkably, CDC45 emerged as a promising prognostic indicator and a novel diagnostic biomarker for GC. In a comprehensive the drug susceptibility analysis, we found that patients with high expression of CDC45 had high sensitivity to various chemotherapeutic agents, among which 5-fluorouracil, docetaxel, cisplatin, and elesclomol were most evident. Furthermore, our findings suggested a plausible association between CDC45 and immune cell infiltration. Enrichment analysis revealed that CDC45 and its associated genes may play crucial roles in muscle biofunction, whereas GSEA demonstrated significant enrichment of gene sets pertaining to G protein-coupled receptor ligand binding and G alpha (i) signaling events. Conclusion Our study elucidates that upregulation of CDC45 is intricately associated with immune cell infiltration and holds promising potential as a favorable prognostic marker and a novel diagnostic biomarker for GC.
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Affiliation(s)
- Lihua Wu
- Affiliated Liutie Central Hospital of Guangxi Medical University, Liuzhou, China
| | - Gan Gao
- Clinical Laboratory, Liuzhou Hospital of Guangzhou Women and Children’s Medical Center, Liuzhou, Guangxi, China
- Guangxi Clinical Research Center for Obstetrics and Gynecology, liuzhou, Guangxi, China
| | - Hui Mi
- Changzhi People’s Hospital, Changzhi, china
| | - Zhou Luo
- Affiliated Liutie Central Hospital of Guangxi Medical University, Liuzhou, China
| | - Zheng Wang
- Affiliated Liutie Central Hospital of Guangxi Medical University, Liuzhou, China
| | - Yongdong Liu
- Affiliated Liutie Central Hospital of Guangxi Medical University, Liuzhou, China
| | - Liangyan Wu
- Affiliated Liutie Central Hospital of Guangxi Medical University, Liuzhou, China
| | - Haihua Long
- Affiliated Liutie Central Hospital of Guangxi Medical University, Liuzhou, China
| | - Yongqi Shen
- Affiliated Liutie Central Hospital of Guangxi Medical University, Liuzhou, China
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3
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Nasheuer HP, Meaney AM. Starting DNA Synthesis: Initiation Processes during the Replication of Chromosomal DNA in Humans. Genes (Basel) 2024; 15:360. [PMID: 38540419 PMCID: PMC10969946 DOI: 10.3390/genes15030360] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2024] [Revised: 03/09/2024] [Accepted: 03/11/2024] [Indexed: 06/14/2024] Open
Abstract
The initiation reactions of DNA synthesis are central processes during human chromosomal DNA replication. They are separated into two main processes: the initiation events at replication origins, the start of the leading strand synthesis for each replicon, and the numerous initiation events taking place during lagging strand DNA synthesis. In addition, a third mechanism is the re-initiation of DNA synthesis after replication fork stalling, which takes place when DNA lesions hinder the progression of DNA synthesis. The initiation of leading strand synthesis at replication origins is regulated at multiple levels, from the origin recognition to the assembly and activation of replicative helicase, the Cdc45-MCM2-7-GINS (CMG) complex. In addition, the multiple interactions of the CMG complex with the eukaryotic replicative DNA polymerases, DNA polymerase α-primase, DNA polymerase δ and ε, at replication forks play pivotal roles in the mechanism of the initiation reactions of leading and lagging strand DNA synthesis. These interactions are also important for the initiation of signalling at unperturbed and stalled replication forks, "replication stress" events, via ATR (ATM-Rad 3-related protein kinase). These processes are essential for the accurate transfer of the cells' genetic information to their daughters. Thus, failures and dysfunctions in these processes give rise to genome instability causing genetic diseases, including cancer. In their influential review "Hallmarks of Cancer: New Dimensions", Hanahan and Weinberg (2022) therefore call genome instability a fundamental function in the development process of cancer cells. In recent years, the understanding of the initiation processes and mechanisms of human DNA replication has made substantial progress at all levels, which will be discussed in the review.
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Affiliation(s)
- Heinz Peter Nasheuer
- Centre for Chromosome Biology, School of Biological and Chemical Sciences, Biochemistry, University of Galway, H91 TK33 Galway, Ireland;
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4
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Radhakrishnan A, Sharma C, Malviya VN, Srivastav R. Deciphering the molecular functionality of Cdc45 in replisomal complex. Biochem Biophys Rep 2024; 37:101643. [PMID: 38298211 PMCID: PMC10828582 DOI: 10.1016/j.bbrep.2024.101643] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Revised: 01/09/2024] [Accepted: 01/09/2024] [Indexed: 02/02/2024] Open
Abstract
The members of DHH superfamily have been reported with diverse substrate spectrum and play pivotal roles in replication, repair, and RNA metabolism. This family comprises phosphatases, phosphoesterase and bifunctional enzymes having nanoRNase and phosphatase activities. Cell cycle factor Cdc45, a member of this superfamily, is crucial for movement of the replication fork during DNA replication and an important component of the replisome. The specific protein-protein interactions of Cdc45 with other factors along with helicase moderate the faithful DNA replication process. However, the exact biochemical functions of this factor are still unknown and need further investigation. Here, we studied the biochemical roles of Cdc45 and its molecular interactions within the replisomal complex. The alteration in the level of protein, observed when DNA damage is induced in-vivo, suggests its association with DNA replication stress. We analyzed protein Cdc45, providing new insights about the molecular and biochemical functionality of this replisomal factor.
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Affiliation(s)
| | - Chandresh Sharma
- Translational Health Science and Technology Institute, Haryana, India
| | - Viveka Nand Malviya
- Department of Neurobiology, Max Planck Institute for Multidisciplinary Sciences, Gottingen, Germany
| | - Rajpal Srivastav
- Amity Institute of Biotechnology, Amity University Uttar Pardesh, Noida, India
- Department of Science & Technology, Ministry of Science & Technology, New Delhi, India
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5
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Guilz NC, Ahn YO, Seo S, Mace EM. Unwinding the Role of the CMG Helicase in Inborn Errors of Immunity. J Clin Immunol 2023; 43:847-861. [PMID: 36809597 PMCID: PMC10789183 DOI: 10.1007/s10875-023-01437-3] [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: 10/31/2022] [Accepted: 01/20/2023] [Indexed: 02/23/2023]
Abstract
Inborn errors of immunity (IEI) are a collection of diseases resulting from genetic causes that impact the immune system through multiple mechanisms. Natural killer cell deficiency (NKD) is one such IEI where natural killer (NK) cells are the main immune lineage affected. Though rare, the deficiency of several genes has been described as underlying causes of NKD, including MCM4, GINS1, MCM10 , and GINS4 , all of which are involved in the eukaryotic CMG helicase. The CMG helicase is made up of C DC45 – M CM – G INS and accessory proteins including MCM10. The CMG helicase plays a critical role in DNA replication by unwinding the double helix and enabling access of polymerases to single-stranded DNA, and thus helicase proteins are active in any proliferating cell. Replication stress, DNA damage, and cell cycle arrest are among the cellular phenotypes attributed to loss of function variants in CMG helicase proteins. Despite the ubiquitous function of the CMG helicase, NK cells have an apparent susceptibility to the deficiency of helicase proteins. This review will examine the role of the CMG helicase in inborn errors of immunity through the lens of NKD and further discuss why natural killer cells can be so strongly affected by helicase deficiency.
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Affiliation(s)
- Nicole C Guilz
- Vagelos College of Physicians and Surgeons, Department of Pediatrics, Columbia University Irving Medical Center, 630 W 168th St., New York, NY, 10032, USA
| | - Yong-Oon Ahn
- Vagelos College of Physicians and Surgeons, Department of Pediatrics, Columbia University Irving Medical Center, 630 W 168th St., New York, NY, 10032, USA
| | - Seungmae Seo
- Vagelos College of Physicians and Surgeons, Department of Pediatrics, Columbia University Irving Medical Center, 630 W 168th St., New York, NY, 10032, USA
| | - Emily M Mace
- Vagelos College of Physicians and Surgeons, Department of Pediatrics, Columbia University Irving Medical Center, 630 W 168th St., New York, NY, 10032, USA.
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6
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Zong C, Zhang Z, Gao L, He J, Wang Y, Li Q, Liu X, Yang J, Chen D, Huang R, Zheng G, Jin X, Wei W, Jia R, Shen J. APOBEC3B coordinates R-loop to promote replication stress and sensitize cancer cells to ATR/Chk1 inhibitors. Cell Death Dis 2023; 14:348. [PMID: 37270643 DOI: 10.1038/s41419-023-05867-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Revised: 05/08/2023] [Accepted: 05/16/2023] [Indexed: 06/05/2023]
Abstract
The cytidine deaminase, Apolipoprotein B mRNA editing enzyme catalytic subunit 3B (APOBEC3B, herein termed A3B), is a critical mutation driver that induces genomic instability in cancer by catalyzing cytosine-to-thymine (C-to-T) conversion and promoting replication stress (RS). However, the detailed function of A3B in RS is not fully determined and it is not known whether the mechanism of A3B action can be exploited for cancer therapy. Here, we conducted an immunoprecipitation-mass spectrometry (IP-MS) study and identified A3B to be a novel binding component of R-loops, which are RNA:DNA hybrid structures. Mechanistically, overexpression of A3B exacerbated RS by promoting R-loop formation and altering the distribution of R-loops in the genome. This was rescued by the R-loop gatekeeper, Ribonuclease H1 (RNASEH1, herein termed RNH1). In addition, a high level of A3B conferred sensitivity to ATR/Chk1 inhibitors (ATRi/Chk1i) in melanoma cells, which was dependent on R-loop status. Together, our results provide novel insights into the mechanistic link between A3B and R-loops in the promotion of RS in cancer. This will inform the development of markers to predict the response of patients to ATRi/Chk1i.
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Affiliation(s)
- Chunyan Zong
- Department of Ophthalmology, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
- Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, 200025, China
- Institute of Translational Medicine, National Facility for Translational Medicine, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Zhe Zhang
- Department of Ophthalmology, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
- Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, 200025, China
- Institute of Translational Medicine, National Facility for Translational Medicine, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Li Gao
- CAS Key Laboratory of Computational Biology, Shanghai Institute of Nutrition and Health, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, 200031, China
| | - Jie He
- Department of Ophthalmology, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
- Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, 200025, China
- Institute of Translational Medicine, National Facility for Translational Medicine, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Yiran Wang
- Department of Ophthalmology, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
- Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, 200025, China
- Institute of Translational Medicine, National Facility for Translational Medicine, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Qian Li
- Department of Ophthalmology, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
- Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, 200025, China
- Institute of Translational Medicine, National Facility for Translational Medicine, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Xiaoting Liu
- Department of Ophthalmology, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
- Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, 200025, China
| | - Jie Yang
- Department of Ophthalmology, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
- Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, 200025, China
| | - Di Chen
- Department of Ophthalmology, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
- Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, 200025, China
- Institute of Translational Medicine, National Facility for Translational Medicine, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Rui Huang
- Department of Ophthalmology, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
- Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, 200025, China
- Institute of Translational Medicine, National Facility for Translational Medicine, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Guopei Zheng
- Department of Ophthalmology, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
- Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, 200025, China
- Institute of Translational Medicine, National Facility for Translational Medicine, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Xiaoliang Jin
- Department of Ophthalmology, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
- Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, 200025, China
| | - Wu Wei
- CAS Key Laboratory of Computational Biology, Shanghai Institute of Nutrition and Health, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, 200031, China.
- Lingang Laboratory, Shanghai, 200031, China.
| | - Renbing Jia
- Department of Ophthalmology, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China.
- Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, 200025, China.
- Institute of Translational Medicine, National Facility for Translational Medicine, Shanghai Jiao Tong University, Shanghai, 200240, China.
| | - Jianfeng Shen
- Department of Ophthalmology, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China.
- Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, 200025, China.
- Institute of Translational Medicine, National Facility for Translational Medicine, Shanghai Jiao Tong University, Shanghai, 200240, China.
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7
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Wei C, Sun W, Liu C, Meng F, Sun L, Ding X. Hsa_circ_0062270 Promotes Tumorigenesis of Melanoma by Stabilizing the Linear Transcript Cell Division Cycle Protein 45. Front Genet 2022; 13:897440. [PMID: 35620458 PMCID: PMC9127359 DOI: 10.3389/fgene.2022.897440] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Accepted: 04/25/2022] [Indexed: 11/15/2022] Open
Abstract
Background: To elucidate the potential biological function of hsa_circ_0062270 in the malignant process of melanoma and its potential target. Methods: Quantitative real-time polymerase chain reaction (qRT-PCR) was conducted to examine relative level of hsa_circ_0062270 in melanoma tissues and normal skin tissues. The diagnostic and prognostic potentials of hsa_circ_0062270 in melanoma were evaluated. The regulatory effect of hsa_circ_0062270 on the expression of linear transcript Cell division cycle protein 45 (CDC45) was also examined. Results: Hsa_circ_0062270 was up-regulated in melanoma samples and cell lines, which displayed certain diagnostic and prognostic potentials in melanoma. Inhibition of hsa_circ_0062270 attenuated the proliferative, migratory and invasive functions. Hsa_circ_0062270 could stabilize the expression of linear transcript CDC45, and thus participated in the malignant process of melanoma. Conclusion: Hsa_circ_0062270 promotes proliferative, migratory and invasive functions of melanoma cells via stabilizing the linear transcript CDC45. Hsa_circ_0062270 can be used to diagnosis and treatment of melanoma.
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Affiliation(s)
- Cuie Wei
- Department of Plastic Surgery, The First People’s Hospital of Lianyungang, Lianyungang, China
| | - Wentao Sun
- Department of Plastic Surgery, The First Affiliated Hospital of Kunming Medical University, Kunming, China
| | - Changhai Liu
- Department of Plastic Surgery, The First People’s Hospital of Lianyungang, Lianyungang, China
| | - Fanjun Meng
- Department of Plastic Surgery, The First People’s Hospital of Lianyungang, Lianyungang, China
| | - Lele Sun
- Department of Plastic Surgery, The First People’s Hospital of Lianyungang, Lianyungang, China
| | - Xiangsheng Ding
- Department of Plastic Surgery, The First People’s Hospital of Lianyungang, Lianyungang, China
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8
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Gao M, Guo G, Huang J, Hou X, Ham H, Kim W, Zhao F, Tu X, Zhou Q, Zhang C, Zhu Q, Liu J, Yan Y, Xu Z, Yin P, Luo K, Weroha J, Deng M, Billadeau DD, Lou Z. DOCK7 protects against replication stress by promoting RPA stability on chromatin. Nucleic Acids Res 2021; 49:3322-3337. [PMID: 33704464 PMCID: PMC8034614 DOI: 10.1093/nar/gkab134] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2020] [Revised: 01/21/2021] [Accepted: 03/02/2021] [Indexed: 02/05/2023] Open
Abstract
RPA is a critical factor for DNA replication and replication stress response. Surprisingly, we found that chromatin RPA stability is tightly regulated. We report that the GDP/GTP exchange factor DOCK7 acts as a critical replication stress regulator to promote RPA stability on chromatin. DOCK7 is phosphorylated by ATR and then recruited by MDC1 to the chromatin and replication fork during replication stress. DOCK7-mediated Rac1/Cdc42 activation leads to the activation of PAK1, which subsequently phosphorylates RPA1 at S135 and T180 to stabilize chromatin-loaded RPA1 and ensure proper replication stress response. Moreover, DOCK7 is overexpressed in ovarian cancer and depleting DOCK7 sensitizes cancer cells to camptothecin. Taken together, our results highlight a novel role for DOCK7 in regulation of the replication stress response and highlight potential therapeutic targets to overcome chemoresistance in cancer.
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Affiliation(s)
- Ming Gao
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN 55905, USA.,Department of Oncology, Mayo Clinic, Rochester, MN 55905, USA
| | - Guijie Guo
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN 55905, USA.,Department of Oncology, Mayo Clinic, Rochester, MN 55905, USA
| | - Jinzhou Huang
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN 55905, USA.,Department of Oncology, Mayo Clinic, Rochester, MN 55905, USA
| | - Xiaonan Hou
- Department of Medical Oncology, Mayo Clinic, Rochester, MN 55905, USA
| | - Hyoungjun Ham
- Department of Biochemistry and Molecular Biology, Division of Oncology Research, Mayo Clinic, Rochester, MN 55905, USA
| | - Wootae Kim
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN 55905, USA.,Department of Oncology, Mayo Clinic, Rochester, MN 55905, USA
| | - Fei Zhao
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN 55905, USA.,Department of Oncology, Mayo Clinic, Rochester, MN 55905, USA
| | - Xinyi Tu
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN 55905, USA.,Department of Oncology, Mayo Clinic, Rochester, MN 55905, USA
| | - Qin Zhou
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN 55905, USA.,Department of Oncology, Mayo Clinic, Rochester, MN 55905, USA
| | - Chao Zhang
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN 55905, USA.,Department of Oncology, Mayo Clinic, Rochester, MN 55905, USA
| | - Qian Zhu
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN 55905, USA.,Department of Oncology, Mayo Clinic, Rochester, MN 55905, USA
| | - Jiaqi Liu
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN 55905, USA.,Department of Oncology, Mayo Clinic, Rochester, MN 55905, USA
| | - Yuanliang Yan
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN 55905, USA.,Department of Oncology, Mayo Clinic, Rochester, MN 55905, USA
| | - Zhijie Xu
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN 55905, USA.,Department of Oncology, Mayo Clinic, Rochester, MN 55905, USA
| | - Ping Yin
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN 55905, USA.,Department of Oncology, Mayo Clinic, Rochester, MN 55905, USA
| | - Kuntian Luo
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN 55905, USA.,Department of Oncology, Mayo Clinic, Rochester, MN 55905, USA
| | - John Weroha
- Department of Medical Oncology, Mayo Clinic, Rochester, MN 55905, USA
| | - Min Deng
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN 55905, USA.,Department of Oncology, Mayo Clinic, Rochester, MN 55905, USA
| | - Daniel D Billadeau
- Department of Biochemistry and Molecular Biology, Division of Oncology Research, Mayo Clinic, Rochester, MN 55905, USA
| | - Zhenkun Lou
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN 55905, USA.,Department of Oncology, Mayo Clinic, Rochester, MN 55905, USA
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9
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Huang TT, Brill E, Nair JR, Zhang X, Wilson KM, Chen L, Thomas CJ, Lee JM. Targeting the PI3K/mTOR Pathway Augments CHK1 Inhibitor-Induced Replication Stress and Antitumor Activity in High-Grade Serous Ovarian Cancer. Cancer Res 2020; 80:5380-5392. [PMID: 32998994 DOI: 10.1158/0008-5472.can-20-1439] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Revised: 08/04/2020] [Accepted: 09/18/2020] [Indexed: 01/08/2023]
Abstract
High-grade serous ovarian carcinoma (HGSOC) is the most lethal gynecologic malignancy in industrialized countries and has limited treatment options. Targeting ataxia-telangiectasia and Rad3-related/cell-cycle checkpoint kinase 1 (CHK1)-mediated S-phase and G2-M-phase cell-cycle checkpoints has been a promising therapeutic strategy in HGSOC. To improve the efficacy of CHK1 inhibitor (CHK1i), we conducted a high-throughput drug combination screening in HGSOC cells. PI3K/mTOR pathway inhibitors (PI3K/mTORi) showed supra-additive cytotoxicity with CHK1i. Combined treatment with CHK1i and PI3K/mTORi significantly attenuated cell viability and increased DNA damage, chromosomal breaks, and mitotic catastrophe compared with monotherapy. PI3K/mTORi decelerated fork speed by promoting new origin firing via increased CDC45, thus potentiating CHK1i-induced replication stress. PI3K/mTORi also augmented CHK1i-induced DNA damage by attenuating DNA homologous recombination repair activity and RAD51 foci formation. High expression of replication stress markers was associated with poor prognosis in patients with HGSOC. Our findings indicate that combined PI3K/mTORi and CHK1i induces greater cell death in HGSOC cells and in vivo models by causing lethal replication stress and DNA damage. This insight can be translated therapeutically by further developing combinations of PI3K and cell-cycle pathway inhibitors in HGSOC. SIGNIFICANCE: Dual inhibition of CHK1 and PI3K/mTOR pathways yields potent synthetic lethality by causing lethal replication stress and DNA damage in HGSOC, warranting further clinical development.
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Affiliation(s)
- Tzu-Ting Huang
- Women's Malignancies Branch, Center for Cancer Research, NCI, Bethesda, Maryland.
| | - Ethan Brill
- Women's Malignancies Branch, Center for Cancer Research, NCI, Bethesda, Maryland
| | - Jayakumar R Nair
- Women's Malignancies Branch, Center for Cancer Research, NCI, Bethesda, Maryland
| | - Xiaohu Zhang
- Division of Preclinical Innovation, National Center for Advancing Translational Sciences, NIH, Bethesda, Maryland
| | - Kelli M Wilson
- Division of Preclinical Innovation, National Center for Advancing Translational Sciences, NIH, Bethesda, Maryland
| | - Lu Chen
- Division of Preclinical Innovation, National Center for Advancing Translational Sciences, NIH, Bethesda, Maryland
| | - Craig J Thomas
- Division of Preclinical Innovation, National Center for Advancing Translational Sciences, NIH, Bethesda, Maryland.,Lymphoid Malignancies Branch, Center for Cancer Research, NCI, Bethesda, Maryland
| | - Jung-Min Lee
- Women's Malignancies Branch, Center for Cancer Research, NCI, Bethesda, Maryland
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10
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Dueva R, Iliakis G. Replication protein A: a multifunctional protein with roles in DNA replication, repair and beyond. NAR Cancer 2020; 2:zcaa022. [PMID: 34316690 PMCID: PMC8210275 DOI: 10.1093/narcan/zcaa022] [Citation(s) in RCA: 54] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 08/23/2020] [Accepted: 08/27/2020] [Indexed: 02/07/2023] Open
Abstract
Single-stranded DNA (ssDNA) forms continuously during DNA replication and is an important intermediate during recombination-mediated repair of damaged DNA. Replication protein A (RPA) is the major eukaryotic ssDNA-binding protein. As such, RPA protects the transiently formed ssDNA from nucleolytic degradation and serves as a physical platform for the recruitment of DNA damage response factors. Prominent and well-studied RPA-interacting partners are the tumor suppressor protein p53, the RAD51 recombinase and the ATR-interacting proteins ATRIP and ETAA1. RPA interactions are also documented with the helicases BLM, WRN and SMARCAL1/HARP, as well as the nucleotide excision repair proteins XPA, XPG and XPF–ERCC1. Besides its well-studied roles in DNA replication (restart) and repair, accumulating evidence shows that RPA is engaged in DNA activities in a broader biological context, including nucleosome assembly on nascent chromatin, regulation of gene expression, telomere maintenance and numerous other aspects of nucleic acid metabolism. In addition, novel RPA inhibitors show promising effects in cancer treatment, as single agents or in combination with chemotherapeutics. Since the biochemical properties of RPA and its roles in DNA repair have been extensively reviewed, here we focus on recent discoveries describing several non-canonical functions.
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Affiliation(s)
- Rositsa Dueva
- Institute of Medical Radiation Biology, University of Duisburg-Essen Medical School, 45122 Essen, Germany
| | - George Iliakis
- Institute of Medical Radiation Biology, University of Duisburg-Essen Medical School, 45122 Essen, Germany
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11
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Onwubiko NO, Borst A, Diaz SA, Passkowski K, Scheffel F, Tessmer I, Nasheuer HP. SV40 T antigen interactions with ssDNA and replication protein A: a regulatory role of T antigen monomers in lagging strand DNA replication. Nucleic Acids Res 2020; 48:3657-3677. [PMID: 32128579 PMCID: PMC7144908 DOI: 10.1093/nar/gkaa138] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Revised: 02/14/2020] [Accepted: 02/26/2020] [Indexed: 01/08/2023] Open
Abstract
DNA replication is a central process in all living organisms. Polyomavirus DNA replication serves as a model system for eukaryotic DNA replication and has considerably contributed to our understanding of basic replication mechanisms. However, the details of the involved processes are still unclear, in particular regarding lagging strand synthesis. To delineate the complex mechanism of coordination of various cellular proteins binding simultaneously or consecutively to DNA to initiate replication, we investigated single-stranded DNA (ssDNA) interactions by the SV40 large T antigen (Tag). Using single molecule imaging by atomic force microscopy (AFM) combined with biochemical and spectroscopic analyses we reveal independent activity of monomeric and oligomeric Tag in high affinity binding to ssDNA. Depending on ssDNA length, we obtain dissociation constants for Tag-ssDNA interactions (KD values of 10–30 nM) that are in the same order of magnitude as ssDNA binding by human replication protein A (RPA). Furthermore, we observe the formation of RPA-Tag-ssDNA complexes containing hexameric as well as monomeric Tag forms. Importantly, our data clearly show stimulation of primase function in lagging strand Okazaki fragment synthesis by monomeric Tag whereas hexameric Tag inhibits the reaction, redefining DNA replication initiation on the lagging strand.
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Affiliation(s)
- Nichodemus O Onwubiko
- Biochemistry, School of Natural Sciences, Center for Chromosome Biology, Biomedical SciencesBuilding, NUI Galway, New Castle Road, Galway, Ireland
| | - Angela Borst
- Rudolf Virchow Center for Experimental Biomedicine, University ofWürzburg, Josef Schneider Strasse 2, 97080 Würzburg, Germany
| | - Suraya A Diaz
- Biochemistry, School of Natural Sciences, Center for Chromosome Biology, Biomedical SciencesBuilding, NUI Galway, New Castle Road, Galway, Ireland
| | - Katharina Passkowski
- Rudolf Virchow Center for Experimental Biomedicine, University ofWürzburg, Josef Schneider Strasse 2, 97080 Würzburg, Germany
| | - Felicia Scheffel
- Rudolf Virchow Center for Experimental Biomedicine, University ofWürzburg, Josef Schneider Strasse 2, 97080 Würzburg, Germany
| | - Ingrid Tessmer
- Rudolf Virchow Center for Experimental Biomedicine, University ofWürzburg, Josef Schneider Strasse 2, 97080 Würzburg, Germany
| | - Heinz P Nasheuer
- Biochemistry, School of Natural Sciences, Center for Chromosome Biology, Biomedical SciencesBuilding, NUI Galway, New Castle Road, Galway, Ireland
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12
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DNA replication protein Cdc45 directly interacts with PCNA via its PIP box in Leishmania donovani and the Cdc45 PIP box is essential for cell survival. PLoS Pathog 2020; 16:e1008190. [PMID: 32413071 PMCID: PMC7255605 DOI: 10.1371/journal.ppat.1008190] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 05/28/2020] [Accepted: 04/16/2020] [Indexed: 12/22/2022] Open
Abstract
DNA replication protein Cdc45 is an integral part of the eukaryotic replicative helicase whose other components are the Mcm2-7 core, and GINS. We identified a PIP box motif in Leishmania donovani Cdc45. This motif is typically linked to interaction with the eukaryotic clamp proliferating cell nuclear antigen (PCNA). The homotrimeric PCNA can potentially bind upto three different proteins simultaneously via a loop region present in each monomer. Multiple binding partners have been identified from among the replication machinery in other eukaryotes, and the concerted /sequential binding of these partners are central to the fidelity of the replication process. Though conserved in Cdc45 across Leishmania species and Trypanosoma cruzi, the PIP box is absent in Trypanosoma brucei Cdc45. Here we investigate the possibility of Cdc45-PCNA interaction and the role of such an interaction in the in vivo context. Having confirmed the importance of Cdc45 in Leishmania DNA replication we establish that Cdc45 and PCNA interact stably in whole cell extracts, also interacting with each other directly in vitro. The interaction is mediated via the Cdc45 PIP box. This PIP box is essential for Leishmania survival. The importance of the Cdc45 PIP box is also examined in Schizosaccharomyces pombe, and it is found to be essential for cell survival here as well. Our results implicate a role for the Leishmania Cdc45 PIP box in recruiting or stabilizing PCNA on chromatin. The Cdc45-PCNA interaction might help tether PCNA and associated replicative DNA polymerase to the DNA template, thus facilitating replication fork elongation. Though multiple replication proteins that associate with PCNA have been identified in other eukaryotes, this is the first report demonstrating a direct interaction between Cdc45 and PCNA, and while our analysis suggests the interaction may not occur in human cells, it indicates that it may not be confined to trypanosomatids.
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13
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Moiseeva TN, Bakkenist CJ. Regulation of the initiation of DNA replication in human cells. DNA Repair (Amst) 2018; 72:99-106. [PMID: 30266203 DOI: 10.1016/j.dnarep.2018.09.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Accepted: 09/07/2018] [Indexed: 12/31/2022]
Abstract
The origin of species would not have been possible without high fidelity DNA replication and complex genomes evolved with mechanisms that control the initiation of DNA replication at multiple origins on multiple chromosomes such that the genome is duplicated once and only once. The mechanisms that control the assembly and activation of the replicative helicase and the initiation of DNA replication in yeast and Xenopus egg extract systems have been identified and reviewed [1,2]. The goal of this review is to organize currently available data on the mechanisms that control the initiation of DNA replication in human cells.
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Affiliation(s)
- Tatiana N Moiseeva
- Department of Radiation Oncology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.
| | - Christopher J Bakkenist
- Department of Radiation Oncology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA; Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
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14
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Kurniawan F, Shi K, Kurahashi K, Bielinsky AK, Aihara H. Crystal Structure of Entamoeba histolytica Cdc45 Suggests a Conformational Switch that May Regulate DNA Replication. iScience 2018; 3:102-109. [PMID: 29901028 PMCID: PMC5994768 DOI: 10.1016/j.isci.2018.04.011] [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] [Indexed: 10/29/2022] Open
Abstract
Cdc45 plays a critical role at the core of the eukaryotic DNA replisome, serving as an essential scaffolding component of the replicative helicase holoenzyme Cdc45-MCM-GINS (CMG) complex. A 1.66-Å-resolution crystal structure of the full-length Cdc45 protein from Entamoeba histolytica shows a protein fold similar to that observed previously for human Cdc45 in its active conformation, featuring the overall disk-like monomer shape and intimate contacts between the N- and C-terminal DHH domains. However, the E. histolytica Cdc45 structure shows several unique features, including a distinct orientation of the C-terminal DHHA1 domain, concomitant disordering of the adjacent protruding α-helical segment implicated in DNA polymerase ε interactions, and a unique conformation of the GINS/Mcm5-binding loop. These structural observations collectively suggest the possibility that Cdc45 can sample multiple conformations corresponding to different functional states. We propose that such conformational switch of Cdc45 may allow regulation of protein-protein interactions important in DNA replication.
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Affiliation(s)
- Fredy Kurniawan
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
| | - Ke Shi
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
| | - Kayo Kurahashi
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
| | - Anja-Katrin Bielinsky
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
| | - Hideki Aihara
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA.
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Nagata M, Ishino S, Yamagami T, Ogino H, Simons JR, Kanai T, Atomi H, Ishino Y. The Cdc45/RecJ-like protein forms a complex with GINS and MCM, and is important for DNA replication in Thermococcus kodakarensis. Nucleic Acids Res 2017; 45:10693-10705. [PMID: 28977567 PMCID: PMC5737688 DOI: 10.1093/nar/gkx740] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2017] [Accepted: 08/12/2017] [Indexed: 01/18/2023] Open
Abstract
The archaeal minichromosome maintenance (MCM) has DNA helicase activity, which is stimulated by GINS in several archaea. In the eukaryotic replicative helicase complex, Cdc45 forms a complex with MCM and GINS, named as CMG (Cdc45-MCM-GINS). Cdc45 shares sequence similarity with bacterial RecJ. A Cdc45/RecJ-like protein from Thermococcus kodakarensis shows a bacterial RecJ-like exonuclease activity, which is stimulated by GINS in vitro. Therefore, this archaeal Cdc45/RecJ is designated as GAN, from GINS-associated nuclease. In this study, we identified the CMG-like complex in T. kodakarensis cells. The GAN·GINS complex stimulated the MCM helicase, but MCM did not affect the nuclease activity of GAN in vitro. The gene disruption analysis showed that GAN was non-essential for its viability but the Δgan mutant did not grow at 93°C. Furthermore, the Δgan mutant showed a clear retardation in growth as compared with the parent cells under optimal conditions at 85°C. These deficiencies were recovered by introducing the gan gene encoding the nuclease deficient GAN protein back to the genome. These results suggest that the replicative helicase complex without GAN may become unstable and ineffective in replication fork progression. The nuclease activity of GAN is not related to the growth defects of the Δgan mutant cells.
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Affiliation(s)
- Mariko Nagata
- Department of Bioscience and Biotechnology, Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University, Fukuoka, Fukuoka 812-8581, Japan
| | - Sonoko Ishino
- Department of Bioscience and Biotechnology, Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University, Fukuoka, Fukuoka 812-8581, Japan
| | - Takeshi Yamagami
- Department of Bioscience and Biotechnology, Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University, Fukuoka, Fukuoka 812-8581, Japan
| | - Hiromi Ogino
- Department of Bioscience and Biotechnology, Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University, Fukuoka, Fukuoka 812-8581, Japan
| | - Jan-Robert Simons
- Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Kyoto, Kyoto 615-8510, Japan
| | - Tamotsu Kanai
- Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Kyoto, Kyoto 615-8510, Japan
| | - Haruyuki Atomi
- Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Kyoto, Kyoto 615-8510, Japan
| | - Yoshizumi Ishino
- Department of Bioscience and Biotechnology, Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University, Fukuoka, Fukuoka 812-8581, Japan
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16
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Eukaryotic Replicative Helicase Subunit Interaction with DNA and Its Role in DNA Replication. Genes (Basel) 2017; 8:genes8040117. [PMID: 28383499 PMCID: PMC5406864 DOI: 10.3390/genes8040117] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2017] [Revised: 03/23/2017] [Accepted: 03/31/2017] [Indexed: 01/30/2023] Open
Abstract
The replicative helicase unwinds parental double-stranded DNA at a replication fork to provide single-stranded DNA templates for the replicative polymerases. In eukaryotes, the replicative helicase is composed of the Cdc45 protein, the heterohexameric ring-shaped Mcm2-7 complex, and the tetrameric GINS complex (CMG). The CMG proteins bind directly to DNA, as demonstrated by experiments with purified proteins. The mechanism and function of these DNA-protein interactions are presently being investigated, and a number of important discoveries relating to how the helicase proteins interact with DNA have been reported recently. While some of the protein-DNA interactions directly relate to the unwinding function of the enzyme complex, other protein-DNA interactions may be important for minichromosome maintenance (MCM) loading, origin melting or replication stress. This review describes our current understanding of how the eukaryotic replicative helicase subunits interact with DNA structures in vitro, and proposed models for the in vivo functions of replicative helicase-DNA interactions are also described.
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