1
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Kim S, Yamada S, Li T, Canasto-Chibuque C, Kim JH, Marcet-Ortega M, Xu J, Eng DY, Feeney L, Petrini JHJ, Keeney S. The MRE11-RAD50-NBS1 complex both starts and extends DNA end resection in mouse meiosis. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.08.17.608390. [PMID: 39185212 PMCID: PMC11343206 DOI: 10.1101/2024.08.17.608390] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/27/2024]
Abstract
Nucleolytic resection of DNA ends is critical for homologous recombination, but its mechanism is not fully understood, particularly in mammalian meiosis. Here we examine roles of the conserved MRN complex (MRE11, RAD50, and NBS1) through genome-wide analysis of meiotic resection in mice with various MRN mutations, including several that cause chromosomal instability in humans. Meiotic DSBs form at elevated levels but remain unresected if Mre11 is conditionally deleted, thus MRN is required for both resection initiation and regulation of DSB numbers. Resection lengths are reduced to varying degrees in MRN hypomorphs or if MRE11 nuclease activity is attenuated in a conditional nuclease-dead Mre11 model. These findings unexpectedly establish that MRN is needed for longer-range extension of resection, not just resection initiation. Finally, resection defects are additively worsened by combining MRN and Exo1 mutations, and mice that are unable to initiate resection or have greatly curtailed resection lengths experience catastrophic spermatogenic failure. Our results elucidate multiple functions of MRN in meiotic recombination, uncover unanticipated relationships between short- and long-range resection, and establish the importance of resection for mammalian meiosis.
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2
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Tang Z, Liang Z, Zhang B, Xu X, Li P, Li L, Lu LY, Liu Y. MRE11 is essential for the long-term viability of undifferentiated spermatogonia. Cell Prolif 2024:e13685. [PMID: 38894566 DOI: 10.1111/cpr.13685] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2023] [Revised: 05/16/2024] [Accepted: 05/21/2024] [Indexed: 06/21/2024] Open
Abstract
In the meiotic prophase, programmed SPO11-linked DNA double-strand breaks (DSBs) are repaired by homologous recombination (HR). The MRE11-RAD50-NBS1 (MRN) complex is essential for initiating DNA end resection, the first step of HR. However, residual DNA end resection still occurs in Nbs1 knockout (KO) spermatocytes for unknown reasons. Here, we show that DNA end resection is completely abolished in Mre11 KO spermatocytes. In addition, Mre11 KO, but not Nbs1 KO, undifferentiated spermatogonia are rapidly exhausted due to DSB accumulation, proliferation defects, and elevated apoptosis. Cellular studies reveal that a small amount of MRE11 retained in the nucleus of Nbs1 KO cells likely underlies the differences between Mre11 and Nbs1 KO cells. Taken together, our study not only demonstrates an irreplaceable role of the MRE11 in DNA end resection at SPO11-linked DSBs but also unveils a unique function of MRE11 in maintaining the long-term viability of undifferentiated spermatogonia.
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Affiliation(s)
- Zhenghui Tang
- Key Laboratory of Reproductive Genetics (Ministry of Education), Women's Hospital, Zhejiang University School of Medicine, Hangzhou, China
- Institute of Translational Medicine, Zhejiang University School of Medicine, Hangzhou, China
| | - Zhongyang Liang
- Key Laboratory of Reproductive Genetics (Ministry of Education), Women's Hospital, Zhejiang University School of Medicine, Hangzhou, China
- Institute of Translational Medicine, Zhejiang University School of Medicine, Hangzhou, China
| | - Bin Zhang
- Key Laboratory of Reproductive Genetics (Ministry of Education), Women's Hospital, Zhejiang University School of Medicine, Hangzhou, China
- Institute of Translational Medicine, Zhejiang University School of Medicine, Hangzhou, China
| | - Xiaohui Xu
- Zhejiang Provincial Key Laboratory of Precision Diagnosis and Therapy for Major Gynecological Diseases, Women's Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Peng Li
- Key Laboratory of Reproductive Genetics (Ministry of Education), Women's Hospital, Zhejiang University School of Medicine, Hangzhou, China
- Zhejiang Key Laboratory of Maternal and Infant Health, Women's Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Lejun Li
- Key Laboratory of Reproductive Genetics (Ministry of Education), Women's Hospital, Zhejiang University School of Medicine, Hangzhou, China
- Zhejiang Key Laboratory of Maternal and Infant Health, Women's Hospital, Zhejiang University School of Medicine, Hangzhou, China
- Department of Reproductive Endocrinology, Women's Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Lin-Yu Lu
- Key Laboratory of Reproductive Genetics (Ministry of Education), Women's Hospital, Zhejiang University School of Medicine, Hangzhou, China
- Institute of Translational Medicine, Zhejiang University School of Medicine, Hangzhou, China
- Zhejiang University Cancer Center, Hangzhou, China
| | - Yidan Liu
- Key Laboratory of Reproductive Genetics (Ministry of Education), Women's Hospital, Zhejiang University School of Medicine, Hangzhou, China
- Zhejiang Provincial Key Laboratory of Precision Diagnosis and Therapy for Major Gynecological Diseases, Women's Hospital, Zhejiang University School of Medicine, Hangzhou, China
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3
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Hartlerode AJ, Mostafa AM, Orban SK, Benedeck R, Campbell K, Hoenerhoff MJ, Ferguson DO, Sekiguchi JM. Reduced levels of MRE11 cause disease phenotypes distinct from ataxia telangiectasia-like disorder. Hum Mol Genet 2024:ddae101. [PMID: 38888340 DOI: 10.1093/hmg/ddae101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Revised: 05/15/2024] [Indexed: 06/20/2024] Open
Abstract
The MRE11/RAD50/NBS1 (MRN) complex plays critical roles in cellular responses to DNA double-strand breaks. MRN is involved in end binding and processing, and it also induces cell cycle checkpoints by activating the ataxia-telangiectasia mutated (ATM) protein kinase. Hypomorphic pathogenic variants in the MRE11, RAD50, or NBS1 genes cause autosomal recessive genome instability syndromes featuring variable degrees of dwarfism, neurological defects, anemia, and cancer predisposition. Disease-associated MRN alleles include missense and nonsense variants, and many cause reduced protein levels of the entire MRN complex. However, the dramatic variability in the disease manifestation of MRN pathogenic variants is not understood. We sought to determine if low protein levels are a significant contributor to disease sequelae and therefore generated a transgenic murine model expressing MRE11 at low levels. These mice display dramatic phenotypes including small body size, severe anemia, and impaired DNA repair. We demonstrate that, distinct from ataxia telangiectasia-like disorder caused by MRE11 pathogenic missense or nonsense variants, mice and cultured cells expressing low MRE11 levels do not display the anticipated defects in ATM activation. Our findings indicate that ATM signaling can be supported by very low levels of the MRN complex and imply that defective ATM activation results from perturbation of MRN function caused by specific hypomorphic disease mutations. These distinct phenotypic outcomes underline the importance of understanding the impact of specific pathogenic MRE11 variants, which may help direct appropriate early surveillance for patients with these complicated disorders in a clinical setting.
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Affiliation(s)
- Andrea J Hartlerode
- Department of Pathology, University of Michigan Medical School, 109 Zina Pitcher Place, Rm 2067, Ann Arbor, MI 48109-2200, United States
- Department of Human Genetics, University of Michigan Medical School, 109 Zina Pitcher Place, Rm 2063, Ann Arbor, MI 48109-2200, United States
| | - Ahmed M Mostafa
- Department of Pathology, University of Michigan Medical School, 109 Zina Pitcher Place, Rm 2067, Ann Arbor, MI 48109-2200, United States
- Department of Biochemistry, Faculty of Pharmacy, Ain Shams University, Organization of African Unity Street, Cairo, Egypt 11566
| | - Steven K Orban
- Department of Pathology, University of Michigan Medical School, 109 Zina Pitcher Place, Rm 2067, Ann Arbor, MI 48109-2200, United States
| | - Rachel Benedeck
- Department of Pathology, University of Michigan Medical School, 109 Zina Pitcher Place, Rm 2067, Ann Arbor, MI 48109-2200, United States
- Program in Biomedical Sciences PhD Program, University of Michigan Medical School, 1135 Catherine Street, Rm 2960, Ann Arbor, MI 48109, United States
| | - Koral Campbell
- Department of Pathology, University of Michigan Medical School, 109 Zina Pitcher Place, Rm 2067, Ann Arbor, MI 48109-2200, United States
- Program in Biomedical Sciences PhD Program, University of Michigan Medical School, 1135 Catherine Street, Rm 2960, Ann Arbor, MI 48109, United States
| | - Mark J Hoenerhoff
- In Vivo Animal Core, Unit for Laboratory Animal Medicine, University of Michigan Medical School, 2800 Plymouth Road, Ann Arbor, MI 48109, United States
| | - David O Ferguson
- Department of Pathology, University of Michigan Medical School, 109 Zina Pitcher Place, Rm 2067, Ann Arbor, MI 48109-2200, United States
| | - JoAnn M Sekiguchi
- Department of Human Genetics, University of Michigan Medical School, 109 Zina Pitcher Place, Rm 2063, Ann Arbor, MI 48109-2200, United States
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Wei T, Mo L, Wu Z, Zou T, Huang J. Gonadal transcriptome analysis of genes related to sex differentiation and sex development in the Pomacea canaliculata. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY. PART D, GENOMICS & PROTEOMICS 2024; 50:101235. [PMID: 38631127 DOI: 10.1016/j.cbd.2024.101235] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2024] [Revised: 03/28/2024] [Accepted: 04/08/2024] [Indexed: 04/19/2024]
Abstract
As an invasive alien animal, Pomacea canaliculata poses a great danger to the ecology and human beings. Recently, there has been a gradual shift towards bio-friendly control. Based on the development of RNA interference and CRISPR technology as molecular regulatory techniques for pest control, it was determined if the knockout of genes related to sex differentiation in P. canaliculata could induce sterility, thereby helping in population control. However, the knowledge of sex differentiation- and development-related genes in P. canaliculata is currently lacking. Here, transcriptomic approaches were used to study the genes expressed in the two genders of P. canaliculata at various developmental stages. Gonad transcriptomes of immature or mature males and females were compared, revealing 12,063 genes with sex-specific expression, of which 6066 were male- and 5997 were female-specific. Among the latter, 581 and 235 genes were up-regulated in immature and mature females, respectively. The sex-specific expressed genes identified included GnRHR2 and TSSK3 in males and ZAR1 and WNT4 in females. Of the genes, six were involved in reproduction: CCNBLIP1, MND1, DMC1, DLC1, MRE11, and E(sev)2B. Compared to immature snail gonads, the expression of HSP90 and CDK1 was markedly reduced in gonadal. It was hypothesized that the two were associated with the development of females. These findings provided new insights into crucial genetic information on sex differentiation and development in P. canaliculata. Additionally, some candidate genes were explored, which can contribute to future studies on controlling P. canaliculata using molecular regulatory techniques.
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Affiliation(s)
- Tingting Wei
- Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection, Guangxi Normal University, Ministry of Education, Guilin, Guangxi 541006, China; Guangxi Key Laboratory of Rare and Endangered Animal Ecology, Guangxi Normal University, Guilin, Guangxi 541006, China; College of Life Sciences, Guangxi Normal University, Guilin, Guangxi 541006, China
| | - Lili Mo
- Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection, Guangxi Normal University, Ministry of Education, Guilin, Guangxi 541006, China; Guangxi Key Laboratory of Rare and Endangered Animal Ecology, Guangxi Normal University, Guilin, Guangxi 541006, China; College of Life Sciences, Guangxi Normal University, Guilin, Guangxi 541006, China
| | - Zhengjun Wu
- Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection, Guangxi Normal University, Ministry of Education, Guilin, Guangxi 541006, China; Guangxi Key Laboratory of Rare and Endangered Animal Ecology, Guangxi Normal University, Guilin, Guangxi 541006, China; College of Life Sciences, Guangxi Normal University, Guilin, Guangxi 541006, China
| | - Tongxiang Zou
- College of Life Sciences, Guangxi Normal University, Guilin, Guangxi 541006, China.
| | - Jinlong Huang
- Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection, Guangxi Normal University, Ministry of Education, Guilin, Guangxi 541006, China; Guangxi Key Laboratory of Rare and Endangered Animal Ecology, Guangxi Normal University, Guilin, Guangxi 541006, China; College of Life Sciences, Guangxi Normal University, Guilin, Guangxi 541006, China.
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Liu Y, Lin Z, Yan J, Zhang X, Tong MH. A Rad50-null mutation in mouse germ cells causes reduced DSB formation, abnormal DSB end resection and complete loss of germ cells. Development 2024; 151:dev202312. [PMID: 38512324 DOI: 10.1242/dev.202312] [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: 08/30/2023] [Accepted: 03/13/2024] [Indexed: 03/22/2024]
Abstract
The conserved MRE11-RAD50-NBS1/Xrs2 complex is crucial for DNA break metabolism and genome maintenance. Although hypomorphic Rad50 mutation mice showed normal meiosis, both null and hypomorphic rad50 mutation yeast displayed impaired meiosis recombination. However, the in vivo function of Rad50 in mammalian germ cells, particularly its in vivo role in the resection of meiotic double strand break (DSB) ends at the molecular level remains elusive. Here, we have established germ cell-specific Rad50 knockout mouse models to determine the role of Rad50 in mitosis and meiosis of mammalian germ cells. We find that Rad50-deficient spermatocytes exhibit defective meiotic recombination and abnormal synapsis. Mechanistically, using END-seq, we demonstrate reduced DSB formation and abnormal DSB end resection occurs in mutant spermatocytes. We further identify that deletion of Rad50 in gonocytes leads to complete loss of spermatogonial stem cells due to genotoxic stress. Taken together, our results reveal the essential role of Rad50 in mammalian germ cell meiosis and mitosis, and provide in vivo views of RAD50 function in meiotic DSB formation and end resection at the molecular level.
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Affiliation(s)
- Yuefang Liu
- School of Life Science, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Hangzhou 310024, China
| | - Zhen Lin
- State Key Laboratory of Molecular Biology, Shanghai Key Laboratory of Molecular Andrology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | - Junyi Yan
- State Key Laboratory of Molecular Biology, Shanghai Key Laboratory of Molecular Andrology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | - Xi Zhang
- State Key Laboratory of Molecular Biology, Shanghai Key Laboratory of Molecular Andrology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | - Ming-Han Tong
- School of Life Science, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Hangzhou 310024, China
- State Key Laboratory of Molecular Biology, Shanghai Key Laboratory of Molecular Andrology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai 200031, China
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6
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Wang H, Canasto-Chibuque C, Kim JH, Hohl M, Leslie C, Reis-Filho JS, Petrini JH. Chronic Interferon Stimulated Gene Transcription Promotes Oncogene Induced Breast Cancer. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.10.16.562529. [PMID: 37905095 PMCID: PMC10614814 DOI: 10.1101/2023.10.16.562529] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/02/2023]
Abstract
The Mre11 complex (comprising Mre11, Rad50, Nbs1) is integral to the maintenance of genome stability. We previously showed that a hypomorphic Mre11 mutant mouse strain ( Mre11 ATLD1/ATLD1 ) was highly susceptible to oncogene induced breast cancer. Here we used a mammary organoid system to examine which Mre11 dependent responses are tumor suppressive. We found that Mre11 ATLD1/ATLD1 organoids exhibited an elevated interferon stimulated gene (ISG) signature and sustained changes in chromatin accessibility. This Mre11 ATLD1/ATLD1 phenotype depended on DNA binding of a nuclear innate immune sensor, IFI205. Ablation of Ifi205 in Mre11 ATLD1/ATLD1 organoids restored baseline and oncogene-induced chromatin accessibility patterns to those observed in WT . Implantation of Mre11 ATLD1/ATLD1 organoids and activation of oncogene led to aggressive metastatic breast cancer. This outcome was reversed in implanted Ifi205 -/- Mre11 ATLD1/ATLD1 organoids. These data reveal a connection between innate immune signaling and tumor suppression in mammary epithelium. Given the abundance of aberrant DNA structures that arise in the context of genome instability syndromes, the data further suggest that cancer predisposition in those contexts may be partially attributable to tonic innate immune transcriptional programs.
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7
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Petroni M, La Monica V, Fabretti F, Augusto M, Battaglini D, Polonara F, Di Giulio S, Giannini G. The Multiple Faces of the MRN Complex: Roles in Medulloblastoma and Beyond. Cancers (Basel) 2023; 15:3599. [PMID: 37509263 PMCID: PMC10377613 DOI: 10.3390/cancers15143599] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Revised: 07/09/2023] [Accepted: 07/10/2023] [Indexed: 07/30/2023] Open
Abstract
Hypomorphic mutations in MRN complex genes are frequently found in cancer, supporting their role as oncosuppressors. However, unlike canonical oncosuppressors, MRN proteins are often overexpressed in tumor tissues, where they actively work to counteract DSBs induced by both oncogene-dependent RS and radio-chemotherapy. Moreover, at the same time, MRN genes are also essential genes, since the constitutive KO of each component leads to embryonic lethality. Therefore, even though it is paradoxical, MRN genes may work as oncosuppressive, oncopromoting, and essential genes. In this review, we discussed how alterations in the MRN complex impact the physiopathology of cancer, in light of our recent discoveries on the gene-dosage-dependent effect of NBS1 in Medulloblastoma. These updates aim to understand whether MRN complex can be realistically used as a prognostic/predictive marker and/or as a therapeutic target for the treatment of cancer patients in the future.
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Affiliation(s)
- Marialaura Petroni
- Department of Molecular Medicine, University La Sapienza, 00161 Rome, Italy
- Istituto Pasteur-Fondazione Cenci Bolognetti, 00161 Rome, Italy
| | - Veronica La Monica
- Department of Molecular Medicine, University La Sapienza, 00161 Rome, Italy
| | - Francesca Fabretti
- Department of Molecular Medicine, University La Sapienza, 00161 Rome, Italy
| | - Mariaconcetta Augusto
- Department of Molecular Medicine, University La Sapienza, 00161 Rome, Italy
- Center for Life Nano- & Neuro-Science, Istituto Italiano di Tecnologia (IIT), 00161 Rome, Italy
| | - Damiana Battaglini
- Department of Molecular Medicine, University La Sapienza, 00161 Rome, Italy
| | - Francesca Polonara
- Department of Molecular Medicine, University La Sapienza, 00161 Rome, Italy
- Istituto Pasteur-Fondazione Cenci Bolognetti, 00161 Rome, Italy
| | - Stefano Di Giulio
- Department of Molecular Medicine, University La Sapienza, 00161 Rome, Italy
| | - Giuseppe Giannini
- Department of Molecular Medicine, University La Sapienza, 00161 Rome, Italy
- Istituto Pasteur-Fondazione Cenci Bolognetti, 00161 Rome, Italy
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8
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Song J, Ma J, Liu X, Huang Z, Li L, Li L, Luo L, Ni R, He J. The MRN complex maintains the biliary-derived hepatocytes in liver regeneration through ATR-Chk1 pathway. NPJ Regen Med 2023; 8:20. [PMID: 37024481 PMCID: PMC10079969 DOI: 10.1038/s41536-023-00294-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2022] [Accepted: 03/23/2023] [Indexed: 04/08/2023] Open
Abstract
When the proliferation of residual hepatocytes is prohibited, biliary epithelial cells (BECs) transdifferentiate into nascent hepatocytes to accomplish liver regeneration. Despite significant interest in transdifferentiation, little is known about the maintenance of nascent hepatocytes in post-injured environments. Here, we perform an N-ethyl-N-nitrosourea (ENU) forward genetic screen and identify a mutant containing a nonsense mutation in the gene nibrin (nbn), which encodes a component of the Mre11-Rad50-Nbn (MRN) complex that activates DNA damage response (DDR). The regenerated hepatocytes cannot be maintained and exhibit apoptosis in the mutant. Mechanistically, the nbn mutation results in the abrogation of ATR-Chk1 signaling and accumulations of DNA damage in nascent hepatocytes, which eventually induces p53-mediated apoptosis. Furthermore, loss of rad50 or mre11a shows similar phenotypes. This study reveals that the activation of DDR by the MRN complex is essential for the survival of BEC-derived hepatocytes, addressing how to maintain nascent hepatocytes in the post-injured environments.
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Affiliation(s)
- Jingmei Song
- Institute of Developmental Biology and Regenerative Medicine, Southwest University, Beibei, Chongqing, China
| | - Jianlong Ma
- Institute of Developmental Biology and Regenerative Medicine, Southwest University, Beibei, Chongqing, China
| | - Xing Liu
- Institute of Developmental Biology and Regenerative Medicine, Southwest University, Beibei, Chongqing, China
| | - Zhuofu Huang
- Institute of Developmental Biology and Regenerative Medicine, Southwest University, Beibei, Chongqing, China
| | - Lianghui Li
- Institute of Developmental Biology and Regenerative Medicine, Southwest University, Beibei, Chongqing, China
| | - Linke Li
- Institute of Developmental Biology and Regenerative Medicine, Southwest University, Beibei, Chongqing, China
| | - Lingfei Luo
- Institute of Developmental Biology and Regenerative Medicine, Southwest University, Beibei, Chongqing, China
| | - Rui Ni
- Institute of Developmental Biology and Regenerative Medicine, Southwest University, Beibei, Chongqing, China.
| | - Jianbo He
- Institute of Developmental Biology and Regenerative Medicine, Southwest University, Beibei, Chongqing, China.
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9
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Wang Q. The role of forkhead-associated (FHA)-domain proteins in plant biology. PLANT MOLECULAR BIOLOGY 2023; 111:455-472. [PMID: 36849846 DOI: 10.1007/s11103-023-01338-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Accepted: 01/31/2023] [Indexed: 06/18/2023]
Abstract
The forkhead-associated (FHA) domain, a well-characterized small protein module that mediates protein-protein interactions by targeting motifs containing phosphothreonine, is present in many regulatory molecules like protein kinase, phosphatases, transcription factors, and other functional proteins. FHA-domain containing proteins in yeast and human are involved in a large variety of cellular processes such as DNA repair, cell cycle arrest, or pre-mRNA processing. Since the first FHA-domain protein, kinase-associated protein phosphatase (KAPP) was found in plants, the interest in plant FHA-containing proteins has increased dramatically, mainly due to the important role of FHA domain-containing proteins in plant growth and development. In this review, we provide a comprehensive overview of the fundamental properties of FHA domain-containing proteins in plants, and systematically summarized and analyzed the research progress of proteins containing the FHA domain in plants. We also emphasized that AT5G47790 and its homologs may play an important role as the regulatory subunit of protein phosphatase 1 (PP1) in plants.
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Affiliation(s)
- Qiuling Wang
- Institute of Future Agriculture, State Key Laboratory of Crop Stress Biology for Arid Areas, State Key Laboratory of Crop Stress Biology for Arid Areas, Northwest A&F University, Yangling, 712100, Shaanxi, People's Republic of China.
- Key Laboratory of Cell Activities and Stress Adaptations, Ministry of Education, School of Life Sciences, Lanzhou University, Lanzhou, 730000, People's Republic of China.
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10
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Hamilton NA, Jehru AE, Samples WN, Wendel BM, Mokhtari PD, Courcelle CT, Courcelle J. chi sequences switch the RecBCD helicase-nuclease complex from degradative to replicative modes during the completion of DNA replication. J Biol Chem 2023; 299:103013. [PMID: 36781123 PMCID: PMC10025158 DOI: 10.1016/j.jbc.2023.103013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2022] [Revised: 02/07/2023] [Accepted: 02/08/2023] [Indexed: 02/13/2023] Open
Abstract
Accurately completing DNA replication when two forks converge is essential to genomic stability. The RecBCD helicase-nuclease complex plays a central role in completion by promoting resection and joining of the excess DNA created when replisomes converge. chi sequences alter RecBCD activity and localize with cross-over hotspots during sexual events in bacteria, yet their functional role during chromosome replication remains unknown. Here, we use two-dimensional agarose gel analysis to show that chi induces replication on substrates containing convergent forks. The induced-replication is processive, but uncoupled with respect to leading and lagging strand synthesis, and can be suppressed by ter sites which limit replisome progression. Our observations demonstrate that convergent replisomes create a substrate that is processed by RecBCD, and that chi, when encountered, switches RecBCD from a degradative to replicative function. We propose that chi serves to functionally differentiate DNA ends created during completion, which require degradation, from those created by chromosomal double-strand breaks, which require resynthesis.
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Affiliation(s)
| | - Avery E. Jehru
- Department of Biology, Portland State University, Portland, Oregon, USA
| | | | - Brian M. Wendel
- Department of Microbiology, Cornell University, Ithaca, New York, USA
| | | | | | - Justin Courcelle
- Department of Biology, Portland State University, Portland, Oregon, USA
- For correspondence: Justin Courcelle
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11
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Rotheneder M, Stakyte K, van de Logt E, Bartho JD, Lammens K, Fan Y, Alt A, Kessler B, Jung C, Roos WP, Steigenberger B, Hopfner KP. Cryo-EM structure of the Mre11-Rad50-Nbs1 complex reveals the molecular mechanism of scaffolding functions. Mol Cell 2023; 83:167-185.e9. [PMID: 36577401 DOI: 10.1016/j.molcel.2022.12.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Revised: 10/14/2022] [Accepted: 12/03/2022] [Indexed: 12/28/2022]
Abstract
The DNA double-strand break repair complex Mre11-Rad50-Nbs1 (MRN) detects and nucleolytically processes DNA ends, activates the ATM kinase, and tethers DNA at break sites. How MRN can act both as nuclease and scaffold protein is not well understood. The cryo-EM structure of MRN from Chaetomium thermophilum reveals a 2:2:1 complex with a single Nbs1 wrapping around the autoinhibited Mre11 nuclease dimer. MRN has two DNA-binding modes, one ATP-dependent mode for loading onto DNA ends and one ATP-independent mode through Mre11's C terminus, suggesting how it may interact with DSBs and intact DNA. MRNs two 60-nm-long coiled-coil domains form a linear rod structure, the apex of which is assembled by the two joined zinc-hook motifs. Apices from two MRN complexes can further dimerize, forming 120-nm spanning MRN-MRN structures. Our results illustrate the architecture of MRN and suggest how it mechanistically integrates catalytic and tethering functions.
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Affiliation(s)
- Matthias Rotheneder
- Gene Center, Department of Biochemistry, Ludwig Maximilians Universität, Munich, Germany
| | - Kristina Stakyte
- Gene Center, Department of Biochemistry, Ludwig Maximilians Universität, Munich, Germany
| | - Erik van de Logt
- Gene Center, Department of Biochemistry, Ludwig Maximilians Universität, Munich, Germany
| | - Joseph D Bartho
- Gene Center, Department of Biochemistry, Ludwig Maximilians Universität, Munich, Germany
| | - Katja Lammens
- Gene Center, Department of Biochemistry, Ludwig Maximilians Universität, Munich, Germany
| | - Yilan Fan
- Gene Center, Department of Biochemistry, Ludwig Maximilians Universität, Munich, Germany
| | - Aaron Alt
- Gene Center, Department of Biochemistry, Ludwig Maximilians Universität, Munich, Germany
| | - Brigitte Kessler
- Gene Center, Department of Biochemistry, Ludwig Maximilians Universität, Munich, Germany
| | - Christophe Jung
- Gene Center, Department of Biochemistry, Ludwig Maximilians Universität, Munich, Germany
| | - Wynand P Roos
- Institute for Toxicology, Johannes-Gutenberg-Universität, Mainz, Germany
| | - Barbara Steigenberger
- Mass Spectrometry Core Facility, Max-Planck-Institute of Biochemistry, Martinsried, Germany
| | - Karl-Peter Hopfner
- Gene Center, Department of Biochemistry, Ludwig Maximilians Universität, Munich, Germany.
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12
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Belhadj S, Khurram A, Bandlamudi C, Palou-Márquez G, Ravichandran V, Steinsnyder Z, Wildman T, Catchings A, Kemel Y, Mukherjee S, Fesko B, Arora K, Mehine M, Dandiker S, Izhar A, Petrini J, Domchek S, Nathanson KL, Brower J, Couch F, Stadler Z, Robson M, Walsh M, Vijai J, Berger M, Supek F, Karam R, Topka S, Offit K. NBN Pathogenic Germline Variants are Associated with Pan-Cancer Susceptibility and In Vitro DNA Damage Response Defects. Clin Cancer Res 2023; 29:422-431. [PMID: 36346689 PMCID: PMC9843434 DOI: 10.1158/1078-0432.ccr-22-1703] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2022] [Revised: 08/26/2022] [Accepted: 11/03/2022] [Indexed: 11/09/2022]
Abstract
PURPOSE To explore the role of NBN as a pan-cancer susceptibility gene. EXPERIMENTAL DESIGN Matched germline and somatic DNA samples from 34,046 patients were sequenced using Memorial Sloan Kettering-Integrated Mutation Profiling of Actionable Cancer Targets and presumed pathogenic germline variants (PGV) identified. Allele-specific and gene-centered analysis of enrichment was conducted and a validation cohort of 26,407 pan-cancer patients was analyzed. Functional studies utilized cellular models with analysis of protein expression, MRN complex formation/localization, and viability assessment following treatment with γ-irradiation. RESULTS We identified 83 carriers of 32 NBN PGVs (0.25% of the studied series), 40% of which (33/83) carried the Slavic founder p.K219fs. The frequency of PGVs varied across cancer types. Patients harboring NBN PGVs demonstrated increased loss of the wild-type allele in their tumors [OR = 2.7; confidence interval (CI): 1.4-5.5; P = 0.0024; pan-cancer], including lung and pancreatic tumors compared with breast and colorectal cancers. p.K219fs was enriched across all tumor types (OR = 2.22; CI: 1.3-3.6; P = 0.0018). Gene-centered analysis revealed enrichment of PGVs in cases compared with controls in the European population (OR = 1.9; CI: 1.3-2.7; P = 0.0004), a finding confirmed in the replication cohort (OR = 1.8; CI: 1.2-2.6; P = 0.003). Two novel truncating variants, p.L19* and p.N71fs, produced a 45 kDa fragment generated by alternative translation initiation that maintained binding to MRE11. Cells expressing these fragments showed higher sensitivity to γ-irradiation and lower levels of radiation-induced KAP1 phosphorylation. CONCLUSIONS Burden analyses, biallelic inactivation, and functional evidence support the role of NBN as contributing to a broad cancer spectrum. Further studies in large pan-cancer series and the assessment of epistatic and environmental interactions are warranted to further define these associations.
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Affiliation(s)
- Sami Belhadj
- Clinical Genetics Service, Department of Medicine, Memorial Sloan Kettering Cancer Center (MSKCC), New York, New York
- Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer Center (MSKCC), New York, New York
- Ambry Genetics, Aliso Viejo, California
| | - Aliya Khurram
- Clinical Genetics Service, Department of Medicine, Memorial Sloan Kettering Cancer Center (MSKCC), New York, New York
| | - Chaitanya Bandlamudi
- Department of Pathology, Marie-Josée and Henry R. Kravis Center for Molecular Oncology, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Guillermo Palou-Márquez
- Genome Data Science, Institute for Research in Biomedicine (IRB Barcelona), Barcelona institute for Science and Technology, Barcelona, Spain
| | - Vignesh Ravichandran
- Department of Pathology, Marie-Josée and Henry R. Kravis Center for Molecular Oncology, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Zoe Steinsnyder
- Clinical Genetics Service, Department of Medicine, Memorial Sloan Kettering Cancer Center (MSKCC), New York, New York
| | - Temima Wildman
- Clinical Genetics Service, Department of Medicine, Memorial Sloan Kettering Cancer Center (MSKCC), New York, New York
| | - Amanda Catchings
- Clinical Genetics Service, Department of Medicine, Memorial Sloan Kettering Cancer Center (MSKCC), New York, New York
| | - Yelena Kemel
- Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center (MSKCC), New York, New York
| | - Semanti Mukherjee
- Clinical Genetics Service, Department of Medicine, Memorial Sloan Kettering Cancer Center (MSKCC), New York, New York
| | - Benjamin Fesko
- Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center (MSKCC), New York, New York
| | - Kanika Arora
- Department of Pathology, Marie-Josée and Henry R. Kravis Center for Molecular Oncology, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Miika Mehine
- Department of Pathology, Marie-Josée and Henry R. Kravis Center for Molecular Oncology, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Sita Dandiker
- Clinical Genetics Service, Department of Medicine, Memorial Sloan Kettering Cancer Center (MSKCC), New York, New York
| | - Aalin Izhar
- Clinical Genetics Service, Department of Medicine, Memorial Sloan Kettering Cancer Center (MSKCC), New York, New York
| | - John Petrini
- Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center (MSKCC), New York, New York
| | - Susan Domchek
- Basser Center for BRCA and Abramson Cancer Center, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Katherine L. Nathanson
- Basser Center for BRCA and Abramson Cancer Center, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Jamie Brower
- Basser Center for BRCA and Abramson Cancer Center, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Fergus Couch
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota
| | - Zsofia Stadler
- Clinical Genetics Service, Department of Medicine, Memorial Sloan Kettering Cancer Center (MSKCC), New York, New York
| | - Mark Robson
- Clinical Genetics Service, Department of Medicine, Memorial Sloan Kettering Cancer Center (MSKCC), New York, New York
- Breast Medicine Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Michael Walsh
- Clinical Genetics Service, Department of Medicine, Memorial Sloan Kettering Cancer Center (MSKCC), New York, New York
- Department of Pediatrics, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Joseph Vijai
- Clinical Genetics Service, Department of Medicine, Memorial Sloan Kettering Cancer Center (MSKCC), New York, New York
- Department of Medicine, Weill Cornell Medical College, New York, New York
| | - Michael Berger
- Department of Pathology, Marie-Josée and Henry R. Kravis Center for Molecular Oncology, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Fran Supek
- Genome Data Science, Institute for Research in Biomedicine (IRB Barcelona), Barcelona institute for Science and Technology, Barcelona, Spain
- Catalan Institution for Research and Advanced Studies (ICREA), Barcelona, Spain
| | | | - Sabine Topka
- Clinical Genetics Service, Department of Medicine, Memorial Sloan Kettering Cancer Center (MSKCC), New York, New York
- Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer Center (MSKCC), New York, New York
| | - Kenneth Offit
- Clinical Genetics Service, Department of Medicine, Memorial Sloan Kettering Cancer Center (MSKCC), New York, New York
- Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer Center (MSKCC), New York, New York
- Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center (MSKCC), New York, New York
- Department of Medicine, Weill Cornell Medical College, New York, New York
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13
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Chang Y, Huang Z, Quan H, Li H, Yang S, Song Y, Wang J, Yuan J, Wu C. Construction of a DNA damage repair gene signature for predicting prognosis and immune response in breast cancer. Front Oncol 2023; 12:1085632. [PMID: 36713553 PMCID: PMC9875088 DOI: 10.3389/fonc.2022.1085632] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Accepted: 12/13/2022] [Indexed: 01/13/2023] Open
Abstract
DNA damage repair (DDR) genes are involved in developing breast cancer. Recently, a targeted therapeutic strategy through DNA repair machinery, including PARPi, has initially shown broad development and application prospects in breast cancer therapy. However, few studies that focused on the correlation between the expression level of DNA repair genes, prognosis, and immune response in breast cancer patients have been recently conducted. Herein, we focused on identifying differentially expressed DNA repair genes (DEGs) in breast cancer specimens and normal samples using the Wilcoxon rank-sum test. Biofunction enrichment analysis was performed with DEGs using the R software "cluster Profiler" package. DNA repair genes were involved in multivariate and univariate Cox regression analyses. After the optimization by AIC value, 11 DNA repair genes were sorted as prognostic DNA repair genes for breast cancer patients to calculate risk scores. Simultaneously, a nomogram was used to represent the prognostic model, which was validated using a calibration curve and C-index. Single-sample gene set enrichment analysis (ssGSEA), CIBERSORT algorithms, and ESTIMATE scores were applied to evaluate the immune filtration of tumor samples. Subsequently, anticarcinogen sensitivity analysis was performed using the R software "pRRophetic" package. Unsupervised clustering was used to excavate the correlation between the expression level of prognostic-significant DNA repair genes and clinical features. In summary, 56 DEGs were sorted, and their potential enriched biofunction pathways were revealed. In total, 11 DNA repair genes (UBE2A, RBBP8, RAD50 , FAAP20, RPA3, ENDOV, DDB2, UBE2V2, MRE11 , RRM2B, and PARP3 ) were preserved as prognostic genes to estimate risk score, which was applied to establish the prognostic model and stratified breast cancer patients into two groups with high or low risk. The calibration curve and C-index indicated that they reliably predicted the survival of breast cancer patients. Immune filtration analysis, anticarcinogen sensitivity analysis, and unsupervised clustering were applied to reveal the character of DNA repair genes between low- and high-risk groups. We identified 11 prognosis-significant DNA repair genes to establish prediction models and immune responses in breast cancer patients.
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Affiliation(s)
- Yiming Chang
- Jinzhou Medical University, Shanghai East Hospital, Shanghai, China
| | - Zhiyuan Huang
- Research Center for Translational Medicine, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, China
| | - Hong Quan
- Department of Breast Surgery, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, China
| | - Hui Li
- Department of Gynaecology and Obstetrics, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, China
| | - Shuo Yang
- Department of Medical Imaging, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, China
| | - Yifei Song
- Department of Biochemistry and Molecular Biology, Tongji University School of Medicine, Shanghai, China
| | - Jian Wang
- Department of Pharmacy, Shanghai Pudong New Area People's Hospital, Shanghai, China,*Correspondence: Jian Yuan, ; Chenming Wu, ; Jian Wang,
| | - Jian Yuan
- Research Center for Translational Medicine, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, China,Department of Biochemistry and Molecular Biology, Tongji University School of Medicine, Shanghai, China,Ji’an Hospital, Shanghai East Hospital, Ji’an, China,*Correspondence: Jian Yuan, ; Chenming Wu, ; Jian Wang,
| | - Chenming Wu
- Research Center for Translational Medicine, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, China,*Correspondence: Jian Yuan, ; Chenming Wu, ; Jian Wang,
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14
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Exploring the Origin and Physiological Significance of DNA Double Strand Breaks in the Developing Neuroretina. Int J Mol Sci 2022; 23:ijms23126449. [PMID: 35742893 PMCID: PMC9224223 DOI: 10.3390/ijms23126449] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2022] [Revised: 06/06/2022] [Accepted: 06/07/2022] [Indexed: 02/04/2023] Open
Abstract
Genetic mosaicism is an intriguing physiological feature of the mammalian brain that generates altered genetic information and provides cellular, and prospectively functional, diversity in a manner similar to that of the immune system. However, both its origin and its physiological significance remain poorly characterized. Most, if not all, cases of somatic mosaicism require prior generation and repair of DNA double strand breaks (DSBs). The relationship between DSB generation, neurogenesis, and early neuronal cell death revealed by our studies in the developing retina provides new perspectives on the different mechanisms that contribute to DNA rearrangements in the developing brain. Here, we speculate on the physiological significance of these findings.
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15
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Almuzaini N, Moore M, Robert-Guroff M, Thomas MA. Disruption of NBS1/MRN Complex Formation by E4orf3 Supports NF-κB That Licenses E1B55K-Deleted Adenovirus-Infected Cells to Accumulate DNA>4n. Microbiol Spectr 2022; 10:e0188121. [PMID: 35019694 PMCID: PMC8754114 DOI: 10.1128/spectrum.01881-21] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Accepted: 12/14/2021] [Indexed: 01/16/2023] Open
Abstract
Cells increase their DNA content greater than the G2/M (DNA > 4n) phases along the path to cancer. The signals that support this increase in DNA content remain poorly understood. Cells infected with adenovirus (Ad) similarly develop DNA > 4n and share a need to bypass the DNA damage response (DDR) signals that trigger cell cycle arrest, and/or cell death. Ads with deletion in early region 1B55K (ΔE1B Ad) are oncolytic agents that are currently being explored for use in vaccine delivery. Interestingly, they promote higher levels of DNA > 4n than Ads that contain E1B55K. Existing in these and almost all Ads that are being explored for clinical use, is early region 4 (E4). The Ad E4 open reading frame 3 (E4orf3) is a viral oncogene that interferes with the ability of cells to respond to DNA damage by disrupting MRN complex formation. Our study reveals that E4orf3 is required for the enhanced fraction of ΔE1B Ad-infected cells with DNA > 4n. For that reason, we explored signaling events mediated by E4orf3. We found that in ΔE1B Ad-infected cells, E4orf3, as reported by others, isolates NBS1 in nuclear dots and tracks. This allows for elevated levels of phosphorylated ATM that is linked to transcriptionally active NF-κB. Pharmacological inhibition of NF-κB reduced the fraction of ΔE1B Ad-infected cells with DNA > 4n while pharmacological inhibition of ATM reduced the levels of nuclear NF-κB and the fraction of ΔE1B Ad-infected cells with DNA > 4n and increased the fraction of dead or dying cells with fragmented DNA. This ability of E4orf3 to disrupt MRN complex formation that allows cells to bypass the cell cycle, evade death, and accumulate DNA > 4n, may be linked to its oncogenic potential. IMPORTANCE Genome instability, a hallmark of cancer, exists as part of a cycle that leads to DNA damage and DNA > 4n that further enhances genome instability. Ad E4orf3 is a viral oncogene. Here, we describe E4orf3 mediated signaling events that support DNA > 4n in ΔE1B Ad-infected cells. These signaling events may be linked to the oncogenic potential of E4orf3 and may provide a basis for how some cells survive with DNA > 4n.
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Affiliation(s)
- Nujud Almuzaini
- Department of Biology, College of Arts and Sciences, Howard University, Washington, D.C., USA
| | - Madison Moore
- Department of Biology, College of Arts and Sciences, Howard University, Washington, D.C., USA
| | - Marjorie Robert-Guroff
- Section on Immune Biology of Retroviral Infection, Vaccine Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Michael A. Thomas
- Department of Biology, College of Arts and Sciences, Howard University, Washington, D.C., USA
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16
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Matos-Rodrigues GE, Martins RAP. An Eye in the Replication Stress Response: Lessons From Tissue-Specific Studies in vivo. Front Cell Dev Biol 2021; 9:731308. [PMID: 34805142 PMCID: PMC8599991 DOI: 10.3389/fcell.2021.731308] [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: 06/26/2021] [Accepted: 09/21/2021] [Indexed: 11/29/2022] Open
Abstract
Several inherited human syndromes that severely affect organogenesis and other developmental processes are caused by mutations in replication stress response (RSR) genes. Although the molecular machinery of RSR is conserved, disease-causing mutations in RSR-genes may have distinct tissue-specific outcomes, indicating that progenitor cells may differ in their responses to RSR inactivation. Therefore, understanding how different cell types respond to replication stress is crucial to uncover the mechanisms of RSR-related human syndromes. Here, we review the ocular manifestations in RSR-related human syndromes and summarize recent findings investigating the mechanisms of RSR during eye development in vivo. We highlight a remarkable heterogeneity of progenitor cells responses to RSR inactivation and discuss its implications for RSR-related human syndromes.
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Affiliation(s)
- Gabriel E Matos-Rodrigues
- Programa de Biologia Celular e do Desenvolvimento, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Rodrigo A P Martins
- Programa de Biologia Celular e do Desenvolvimento, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
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17
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Atkins A, Chung CH, Allen AG, Dampier W, Gurrola TE, Sariyer IK, Nonnemacher MR, Wigdahl B. Off-Target Analysis in Gene Editing and Applications for Clinical Translation of CRISPR/Cas9 in HIV-1 Therapy. Front Genome Ed 2021; 3:673022. [PMID: 34713260 PMCID: PMC8525399 DOI: 10.3389/fgeed.2021.673022] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Accepted: 06/21/2021] [Indexed: 12/26/2022] Open
Abstract
As genome-editing nucleases move toward broader clinical applications, the need to define the limits of their specificity and efficiency increases. A variety of approaches for nuclease cleavage detection have been developed, allowing a full-genome survey of the targeting landscape and the detection of a variety of repair outcomes for nuclease-induced double-strand breaks. Each approach has advantages and disadvantages relating to the means of target-site capture, target enrichment mechanism, cellular environment, false discovery, and validation of bona fide off-target cleavage sites in cells. This review examines the strengths, limitations, and origins of the different classes of off-target cleavage detection systems including anchored primer enrichment (GUIDE-seq), in situ detection (BLISS), in vitro selection libraries (CIRCLE-seq), chromatin immunoprecipitation (ChIP) (DISCOVER-Seq), translocation sequencing (LAM PCR HTGTS), and in vitro genomic DNA digestion (Digenome-seq and SITE-Seq). Emphasis is placed on the specific modifications that give rise to the enhanced performance of contemporary techniques over their predecessors and the comparative performance of techniques for different applications. The clinical relevance of these techniques is discussed in the context of assessing the safety of novel CRISPR/Cas9 HIV-1 curative strategies. With the recent success of HIV-1 and SIV-1 viral suppression in humanized mice and non-human primates, respectively, using CRISPR/Cas9, rigorous exploration of potential off-target effects is of critical importance. Such analyses would benefit from the application of the techniques discussed in this review.
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Affiliation(s)
- Andrew Atkins
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, PA, United States,Center for Molecular Virology and Translational Neuroscience, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, PA, United States
| | - Cheng-Han Chung
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, PA, United States,Center for Molecular Virology and Translational Neuroscience, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, PA, United States
| | - Alexander G. Allen
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, PA, United States,Center for Molecular Virology and Translational Neuroscience, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, PA, United States
| | - Will Dampier
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, PA, United States,Center for Molecular Virology and Translational Neuroscience, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, PA, United States
| | - Theodore E. Gurrola
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, PA, United States,Center for Molecular Virology and Translational Neuroscience, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, PA, United States
| | - Ilker K. Sariyer
- Department of Neuroscience and Center for Neurovirology, Temple University Lewis Katz School of Medicine, Philadelphia, PA, United States
| | - Michael R. Nonnemacher
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, PA, United States,Center for Molecular Virology and Translational Neuroscience, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, PA, United States
| | - Brian Wigdahl
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, PA, United States,Center for Molecular Virology and Translational Neuroscience, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, PA, United States,Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA, United States,*Correspondence: Brian Wigdahl
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18
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Rieckher M, Garinis GA, Schumacher B. Molecular pathology of rare progeroid diseases. Trends Mol Med 2021; 27:907-922. [PMID: 34272172 DOI: 10.1016/j.molmed.2021.06.011] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Revised: 06/18/2021] [Accepted: 06/22/2021] [Indexed: 12/21/2022]
Abstract
Progeroid syndromes (PSs) are characterized by the premature onset of age-related pathologies. The genetic mutations underlying PSs are functionally linked to genome maintenance and repair, supporting the causative role of DNA damage accumulation in aging. Recent advances from studies in animal models of PSs have provided new insight into the role of DNA repair mechanisms in human disease and the physiological adaptations to accumulating DNA damage during aging. The molecular pathology of PSs is reminiscent of the natural aging process, highlighting the relevance for a wide range of age-related diseases. Recent progress has led to the development of novel therapeutic strategies against age-related diseases that are relevant to rare diseases as well as the general aging population.
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Affiliation(s)
- Matthias Rieckher
- Institute for Genome Stability in Aging and Disease, Medical Faculty, University of Cologne, Joseph-Stelzmann-Strasse 26, 50931 Cologne, Germany; Cologne Excellence Cluster for Cellular Stress Responses in Aging-Associated Diseases (CECAD) and Center for Molecular Medicine (CMMC), University of Cologne, Joseph-Stelzmann-Strasse 26, 50931 Cologne, Germany
| | - George A Garinis
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, GR70013, Heraklion, Crete, Greece; Department of Biology, University of Crete, Heraklion, Crete, Greece
| | - Björn Schumacher
- Institute for Genome Stability in Aging and Disease, Medical Faculty, University of Cologne, Joseph-Stelzmann-Strasse 26, 50931 Cologne, Germany; Cologne Excellence Cluster for Cellular Stress Responses in Aging-Associated Diseases (CECAD) and Center for Molecular Medicine (CMMC), University of Cologne, Joseph-Stelzmann-Strasse 26, 50931 Cologne, Germany.
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Mouse Models for Deciphering the Impact of Homologous Recombination on Tumorigenesis. Cancers (Basel) 2021; 13:cancers13092083. [PMID: 33923105 PMCID: PMC8123484 DOI: 10.3390/cancers13092083] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Revised: 04/19/2021] [Accepted: 04/20/2021] [Indexed: 12/15/2022] Open
Abstract
Homologous recombination (HR) is a fundamental evolutionarily conserved process that plays prime role(s) in genome stability maintenance through DNA repair and through the protection and resumption of arrested replication forks. Many HR genes are deregulated in cancer cells. Notably, the breast cancer genes BRCA1 and BRCA2, two important HR players, are the most frequently mutated genes in familial breast and ovarian cancer. Transgenic mice constitute powerful tools to unravel the intricate mechanisms controlling tumorigenesis in vivo. However, the genes central to HR are essential in mammals, and their knockout leads to early embryonic lethality in mice. Elaborated strategies have been developed to overcome this difficulty, enabling one to analyze the consequences of HR disruption in vivo. In this review, we first briefly present the molecular mechanisms of HR in mammalian cells to introduce each factor in the HR process. Then, we present the different mouse models of HR invalidation and the consequences of HR inactivation on tumorigenesis. Finally, we discuss the use of mouse models for the development of targeted cancer therapies as well as perspectives on the future potential for understanding the mechanisms of HR inactivation-driven tumorigenesis in vivo.
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20
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ATM: Translating the DNA Damage Response to Adaptive Immunity. Trends Immunol 2021; 42:350-365. [PMID: 33663955 DOI: 10.1016/j.it.2021.02.001] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 01/22/2021] [Accepted: 02/01/2021] [Indexed: 12/20/2022]
Abstract
ATM is often dubbed the master regulator of the DNA double stranded break (DSB) response. Since proper induction and repair of DNA DSBs forms the core of immunological diversity, it is surprising that patients with ataxia telangiectasia generally have a mild immunodeficiency in contrast to other DSB repair syndromes. In this review, we address this discrepancy by delving into the functions of ATM in DSB repair and cell cycle control and translate these to adaptive immunity. We conclude that ATM, despite its myriad functions, is not an absolute requirement for acquiring sufficient levels of immunological diversity to prevent severe viral and opportunistic infections. There is, however, a more clinically pronounced antibody deficiency in ataxia telangiectasia due to disturbed class switch recombination.
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21
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Na J, Newman JA, Then CK, Syed J, Vendrell I, Torrecilla I, Ellermann S, Ramadan K, Fischer R, Kiltie AE. SPRTN protease-cleaved MRE11 decreases DNA repair and radiosensitises cancer cells. Cell Death Dis 2021; 12:165. [PMID: 33558481 PMCID: PMC7870818 DOI: 10.1038/s41419-021-03437-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Revised: 01/07/2021] [Accepted: 01/11/2021] [Indexed: 12/21/2022]
Abstract
The human MRE11/RAD50/NBS1 (MRN) complex plays a crucial role in sensing and repairing DNA DSB. MRE11 possesses dual 3'-5' exonuclease and endonuclease activity and forms the core of the multifunctional MRN complex. We previously identified a C-terminally truncated form of MRE11 (TR-MRE11) associated with post-translational MRE11 degradation. Here we identified SPRTN as the essential protease for the formation of TR-MRE11 and characterised the role of this MRE11 form in its DNA damage response (DDR). Using tandem mass spectrometry and site-directed mutagenesis, the SPRTN-dependent cleavage site for MRE11 was identified between 559 and 580 amino acids. Despite the intact interaction of TR-MRE11 with its constitutive core complex proteins RAD50 and NBS1, both nuclease activities of truncated MRE11 were dramatically reduced due to its deficient binding to DNA. Furthermore, lack of the MRE11 C-terminal decreased HR repair efficiency, very likely due to abolished recruitment of TR-MRE11 to the sites of DNA damage, which consequently led to increased cellular radiosensitivity. The presence of this DNA repair-defective TR-MRE11 could explain our previous finding that the high MRE11 protein expression by immunohistochemistry correlates with improved survival following radical radiotherapy in bladder cancer patients.
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Affiliation(s)
- Juri Na
- MRC Oxford Institute for Radiation Oncology, Department of Oncology, University of Oxford, Oxford, OX3 7DQ, UK
| | - Joseph A Newman
- Centre for Medicines Discovery, University of Oxford, Oxford, UK
| | - Chee Kin Then
- MRC Oxford Institute for Radiation Oncology, Department of Oncology, University of Oxford, Oxford, OX3 7DQ, UK
| | - Junetha Syed
- MRC Oxford Institute for Radiation Oncology, Department of Oncology, University of Oxford, Oxford, OX3 7DQ, UK
| | - Iolanda Vendrell
- MRC Oxford Institute for Radiation Oncology, Department of Oncology, University of Oxford, Oxford, OX3 7DQ, UK
- Target Discovery Institute, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Ignacio Torrecilla
- MRC Oxford Institute for Radiation Oncology, Department of Oncology, University of Oxford, Oxford, OX3 7DQ, UK
| | - Sophie Ellermann
- MRC Oxford Institute for Radiation Oncology, Department of Oncology, University of Oxford, Oxford, OX3 7DQ, UK
| | - Kristijan Ramadan
- MRC Oxford Institute for Radiation Oncology, Department of Oncology, University of Oxford, Oxford, OX3 7DQ, UK
| | - Roman Fischer
- Target Discovery Institute, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Anne E Kiltie
- MRC Oxford Institute for Radiation Oncology, Department of Oncology, University of Oxford, Oxford, OX3 7DQ, UK.
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22
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Fu S, Li Z, Xiao L, Hu W, Zhang L, Xie B, Zhou Q, He J, Qiu Y, Wen M, Peng Y, Gao J, Tan R, Deng Y, Weng L, Sun LQ. Glutamine Synthetase Promotes Radiation Resistance via Facilitating Nucleotide Metabolism and Subsequent DNA Damage Repair. Cell Rep 2020; 28:1136-1143.e4. [PMID: 31365859 DOI: 10.1016/j.celrep.2019.07.002] [Citation(s) in RCA: 81] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2019] [Revised: 03/12/2019] [Accepted: 06/27/2019] [Indexed: 01/10/2023] Open
Abstract
Radiation resistance is a critical problem in radiotherapy for cancer. Radiation kills tumor cells mainly through causing DNA damage. Thus, efficiency of DNA damage repair is one of the most important factors that limits radiotherapy efficacy. Glutamine physiologically functions to generate protein and nucleotides. Here, we study the impact of glutamine metabolism on cancer therapeutic responses, in particular under irradiation-induced stress. We show that radiation-resistant cells possessed low glycolysis, mitochondrial respiration, and TCA cycle but high glutamine anabolism. Transcriptome analyses revealed that glutamine synthetase (GS), an enzyme catalyzing glutamate and ammonia to glutamine, was responsible for the metabolic alteration. ChIP and luciferase reporter assays revealed that GS could be transcriptionally regulated by STAT5. Knockdown of GS delayed DNA repair, weakened nucleotide metabolism, and enhanced radiosensitivity both in vitro and in vivo. Our data show that GS links glutamine metabolism to radiotherapy response through fueling nucleotide synthesis and accelerating DNA repair.
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Affiliation(s)
- Shujun Fu
- Center for Molecular Medicine, Xiangya Hospital, Central South University, Changsha 410008, China; Key Laboratory of Molecular Radiation Oncology Hunan Province, Changsha 410008, China
| | - Zhi Li
- Center for Molecular Medicine, Xiangya Hospital, Central South University, Changsha 410008, China; Key Laboratory of Molecular Radiation Oncology Hunan Province, Changsha 410008, China; Hunan International Science and Technology Collaboration Base of Precision Medicine for Cancer, Changsha 410008, China
| | - Lanbo Xiao
- Cancer Research Institute, Xiangya School of Medicine, Central South University, Changsha 410008, China
| | - Wenfeng Hu
- Center for Molecular Medicine, Xiangya Hospital, Central South University, Changsha 410008, China; Key Laboratory of Molecular Radiation Oncology Hunan Province, Changsha 410008, China
| | - Lu Zhang
- Center for Molecular Medicine, Xiangya Hospital, Central South University, Changsha 410008, China; Key Laboratory of Molecular Radiation Oncology Hunan Province, Changsha 410008, China
| | - Bowen Xie
- Center for Molecular Medicine, Xiangya Hospital, Central South University, Changsha 410008, China; Key Laboratory of Molecular Radiation Oncology Hunan Province, Changsha 410008, China
| | - Qin Zhou
- Department of Oncology, Xiangya Hospital, Central South University, Changsha 410008, China
| | - Junju He
- Center for Molecular Medicine, Xiangya Hospital, Central South University, Changsha 410008, China
| | - Yanfang Qiu
- Center for Molecular Medicine, Xiangya Hospital, Central South University, Changsha 410008, China
| | - Ming Wen
- Center for Molecular Medicine, Xiangya Hospital, Central South University, Changsha 410008, China; Key Laboratory of Molecular Radiation Oncology Hunan Province, Changsha 410008, China
| | - Yanni Peng
- Center for Molecular Medicine, Xiangya Hospital, Central South University, Changsha 410008, China
| | - Jie Gao
- Center for Molecular Medicine, Xiangya Hospital, Central South University, Changsha 410008, China
| | - Rong Tan
- Center for Molecular Medicine, Xiangya Hospital, Central South University, Changsha 410008, China; Key Laboratory of Molecular Radiation Oncology Hunan Province, Changsha 410008, China; Hunan International Science and Technology Collaboration Base of Precision Medicine for Cancer, Changsha 410008, China
| | - Yuezhen Deng
- Center for Molecular Medicine, Xiangya Hospital, Central South University, Changsha 410008, China; Key Laboratory of Molecular Radiation Oncology Hunan Province, Changsha 410008, China; Hunan International Science and Technology Collaboration Base of Precision Medicine for Cancer, Changsha 410008, China
| | - Liang Weng
- Center for Molecular Medicine, Xiangya Hospital, Central South University, Changsha 410008, China; Key Laboratory of Molecular Radiation Oncology Hunan Province, Changsha 410008, China; Hunan International Science and Technology Collaboration Base of Precision Medicine for Cancer, Changsha 410008, China
| | - Lun-Quan Sun
- Center for Molecular Medicine, Xiangya Hospital, Central South University, Changsha 410008, China; Key Laboratory of Molecular Radiation Oncology Hunan Province, Changsha 410008, China; Hunan International Science and Technology Collaboration Base of Precision Medicine for Cancer, Changsha 410008, China; National Clinical Research Center for Gerontology, Changsha 410008, China.
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23
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A Survey of Reported Disease-Related Mutations in the MRE11-RAD50-NBS1 Complex. Cells 2020; 9:cells9071678. [PMID: 32668560 PMCID: PMC7407228 DOI: 10.3390/cells9071678] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Revised: 07/01/2020] [Accepted: 07/06/2020] [Indexed: 12/24/2022] Open
Abstract
The MRE11-RAD50-NBS1 (MRN) protein complex is one of the primary vehicles for repairing DNA double strand breaks and maintaining the genomic stability within the cell. The role of the MRN complex to recognize and process DNA double-strand breaks as well as signal other damage response factors is critical for maintaining proper cellular function. Mutations in any one of the components of the MRN complex that effect function or expression of the repair machinery could be detrimental to the cell and may initiate and/or propagate disease. Here, we discuss, in a structural and biochemical context, mutations in each of the three MRN components that have been associated with diseases such as ataxia telangiectasia-like disorder (ATLD), Nijmegen breakage syndrome (NBS), NBS-like disorder (NBSLD) and certain types of cancers. Overall, deepening our understanding of disease-causing mutations of the MRN complex at the structural and biochemical level is foundational to the future aim of treating diseases associated with these aberrations.
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24
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Forrer Charlier C, Martins RAP. Protective Mechanisms Against DNA Replication Stress in the Nervous System. Genes (Basel) 2020; 11:E730. [PMID: 32630049 PMCID: PMC7397197 DOI: 10.3390/genes11070730] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Revised: 06/25/2020] [Accepted: 06/25/2020] [Indexed: 02/06/2023] Open
Abstract
The precise replication of DNA and the successful segregation of chromosomes are essential for the faithful transmission of genetic information during the cell cycle. Alterations in the dynamics of genome replication, also referred to as DNA replication stress, may lead to DNA damage and, consequently, mutations and chromosomal rearrangements. Extensive research has revealed that DNA replication stress drives genome instability during tumorigenesis. Over decades, genetic studies of inherited syndromes have established a connection between the mutations in genes required for proper DNA repair/DNA damage responses and neurological diseases. It is becoming clear that both the prevention and the responses to replication stress are particularly important for nervous system development and function. The accurate regulation of cell proliferation is key for the expansion of progenitor pools during central nervous system (CNS) development, adult neurogenesis, and regeneration. Moreover, DNA replication stress in glial cells regulates CNS tumorigenesis and plays a role in neurodegenerative diseases such as ataxia telangiectasia (A-T). Here, we review how replication stress generation and replication stress response (RSR) contribute to the CNS development, homeostasis, and disease. Both cell-autonomous mechanisms, as well as the evidence of RSR-mediated alterations of the cellular microenvironment in the nervous system, were discussed.
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Affiliation(s)
| | - Rodrigo A. P. Martins
- Programa de Biologia Celular e do Desenvolvimento, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro 21941-902, Brazil;
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25
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Ragamin A, Yigit G, Bousset K, Beleggia F, Verheijen FW, de Wit MY, Strom TM, Dörk T, Wollnik B, Mancini GMS. Human RAD50 deficiency: Confirmation of a distinctive phenotype. Am J Med Genet A 2020; 182:1378-1386. [PMID: 32212377 PMCID: PMC7318339 DOI: 10.1002/ajmg.a.61570] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2019] [Revised: 02/24/2020] [Accepted: 03/09/2020] [Indexed: 12/13/2022]
Abstract
DNA double-strand breaks (DSBs) are highly toxic DNA lesions that can lead to chromosomal instability, loss of genes and cancer. The MRE11/RAD50/NBN (MRN) complex is keystone involved in signaling processes inducing the repair of DSB by, for example, in activating pathways leading to homologous recombination repair and nonhomologous end joining. Additionally, the MRN complex also plays an important role in the maintenance of telomeres and can act as a stabilizer at replication forks. Mutations in NBN and MRE11 are associated with Nijmegen breakage syndrome (NBS) and ataxia telangiectasia (AT)-like disorder, respectively. So far, only one single patient with biallelic loss of function variants in RAD50 has been reported presenting with features classified as NBS-like disorder. Here, we report a long-term follow-up of an unrelated patient with facial dysmorphisms, microcephaly, skeletal features, and short stature who is homozygous for a novel variant in RAD50. We could show that this variant, c.2524G > A in exon 15 of the RAD50 gene, induces aberrant splicing of RAD50 mRNA mainly leading to premature protein truncation and thereby, most likely, to loss of RAD50 function. Using patient-derived primary fibroblasts, we could show abnormal radioresistant DNA synthesis confirming pathogenicity of the identified variant. Immunoblotting experiments showed strongly reduced protein levels of RAD50 in the patient-derived fibroblasts and provided evidence for a markedly reduced radiation-induced AT-mutated signaling. Comparison with the previously reported case and with patients presenting with NBS confirms that RAD50 mutations lead to a similar, but distinctive phenotype.
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Affiliation(s)
- Aviël Ragamin
- Department of Clinical GeneticsErasmus MC University Medical CenterRotterdamThe Netherlands
| | - Gökhan Yigit
- Institute of Human GeneticsUniversity Medical Center GöttingenGöttingenGermany
| | - Kristine Bousset
- Department of Gynecology and ObstetricsHannover Medical SchoolHannoverGermany
| | - Filippo Beleggia
- Clinic I of Internal MedicineUniversity Hospital CologneCologneGermany
| | - Frans W. Verheijen
- Department of Clinical GeneticsErasmus MC University Medical CenterRotterdamThe Netherlands
| | - Marie‐Claire Y. de Wit
- Department of Child NeurologySophia Children's Hospital, Erasmus MC University Medical CenterRotterdamNetherlands
- ENCORE Expertise Center for Neurodevelopmental DisordersRotterdamThe Netherlands
| | - Tim M. Strom
- Institute of Human GeneticsHelmholtz Zentrum MünchenNeuherbergGermany
- Institute of Human GeneticsTechnische Universität MünchenMunichGermany
| | - Thilo Dörk
- Department of Gynecology and ObstetricsHannover Medical SchoolHannoverGermany
| | - Bernd Wollnik
- Institute of Human GeneticsUniversity Medical Center GöttingenGöttingenGermany
- Cluster of Excellence "Multiscale Bioimaging: From Molecular Machines to Networks of Excitable Cells" (MBExC)University of GöttingenGöttingenGermany
| | - Grazia M. S. Mancini
- Department of Clinical GeneticsErasmus MC University Medical CenterRotterdamThe Netherlands
- ENCORE Expertise Center for Neurodevelopmental DisordersRotterdamThe Netherlands
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26
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Kafer GR, Cesare AJ. A Survey of Essential Genome Stability Genes Reveals That Replication Stress Mitigation Is Critical for Peri-Implantation Embryogenesis. Front Cell Dev Biol 2020; 8:416. [PMID: 32548123 PMCID: PMC7274024 DOI: 10.3389/fcell.2020.00416] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Accepted: 05/05/2020] [Indexed: 12/16/2022] Open
Abstract
Murine development demands that pluripotent epiblast stem cells in the peri-implantation embryo increase from approximately 120 to 14,000 cells between embryonic days (E) 4.5 and E7.5. This is possible because epiblast stem cells can complete cell cycles in under 3 h in vivo. To ensure conceptus fitness, epiblast cells must undertake this proliferative feat while maintaining genome integrity. How epiblast cells maintain genome health under such an immense proliferation demand remains unclear. To illuminate the contribution of genome stability pathways to early mammalian development we systematically reviewed knockout mouse data from 347 DDR and repair associated genes. Cumulatively, the data indicate that while many DNA repair functions are dispensable in embryogenesis, genes encoding replication stress response and homology directed repair factors are essential specifically during the peri-implantation stage of early development. We discuss the significance of these findings in the context of the unique proliferative demands placed on pluripotent epiblast stem cells.
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Affiliation(s)
| | - Anthony J. Cesare
- Genome Integrity Unit, Children’s Medical Research Institute, The University of Sydney, Westmead, NSW, Australia
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27
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Li J, Wang C, Feng G, Zhang L, Chen G, Sun H, Wang J, Zhang Y, Zhou Q, Li W. Rbm14 maintains the integrity of genomic DNA during early mouse embryogenesis via mediating alternative splicing. Cell Prolif 2020; 53:e12724. [PMID: 31794640 PMCID: PMC6985654 DOI: 10.1111/cpr.12724] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2019] [Revised: 10/22/2019] [Accepted: 10/23/2019] [Indexed: 12/22/2022] Open
Abstract
OBJECTIVE In this study, we generated an Rbm14 knockout mouse model to explore its functions during early mouse embryogenesis. MATERIALS AND METHODS The Rbm14 knockout mouse model was generated by a combination of clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 and microinjection techniques. The developmental defects of the knockout embryos were characterized by histological analyses. The accumulation of DNA damage in mouse embryonic stem cells (ESCs) was detected by γH2AX staining and comet assay. The altered mRNA splicing of DNA damage response (DDR)-related genes was detected by RNA-Seq analysis and confirmed by semi-quantitative PCR. The interaction of RBM14 with alternative splicing-related genes was detected by immunoprecipitation-mass spectra (IP-MS) and confirmed by co-immunoprecipitation (Co-IP). RESULTS Rbm14 knockout in mice results in apoptosis and cell proliferation defects in early post-implantation epiblast cells, leading to gastrulation disruption and embryonic lethality. FACS and immunostaining demonstrate accumulation of DNA damage in Rbm14 knockout ES cells. We also identified altered splicing of DDR-related genes in the knockout mouse ESCs by RNA-Seq, indicating that RBM14-mediated alternative splicing is required for the maintenance of genome integrity during early mouse embryogenesis. CONCLUSIONS Our work reveals that Rbm14 plays an essential role in the maintenance of genome integrity during early mouse embryonic development by regulating alternative splicing of DDR-related genes.
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Affiliation(s)
- Jing Li
- School of Life SciencesUniversity of Science and Technology of ChinaHefeiChina
- State Key Laboratory of Stem Cell and Reproductive BiologyInstitute of ZoologyChinese Academy of SciencesBeijingChina
- Institute for Stem Cell and RegenerationChinese Academy of SciencesBeijingChina
| | - Chenxin Wang
- State Key Laboratory of Stem Cell and Reproductive BiologyInstitute of ZoologyChinese Academy of SciencesBeijingChina
- Institute for Stem Cell and RegenerationChinese Academy of SciencesBeijingChina
| | - Guihai Feng
- State Key Laboratory of Stem Cell and Reproductive BiologyInstitute of ZoologyChinese Academy of SciencesBeijingChina
- Institute for Stem Cell and RegenerationChinese Academy of SciencesBeijingChina
| | - Linlin Zhang
- State Key Laboratory of Stem Cell and Reproductive BiologyInstitute of ZoologyChinese Academy of SciencesBeijingChina
- Institute for Stem Cell and RegenerationChinese Academy of SciencesBeijingChina
- University of Chinese Academy of SciencesBeijingChina
| | - Guilai Chen
- State Key Laboratory of Stem Cell and Reproductive BiologyInstitute of ZoologyChinese Academy of SciencesBeijingChina
- Institute for Stem Cell and RegenerationChinese Academy of SciencesBeijingChina
| | - Hao Sun
- State Key Laboratory of Stem Cell and Reproductive BiologyInstitute of ZoologyChinese Academy of SciencesBeijingChina
- Institute for Stem Cell and RegenerationChinese Academy of SciencesBeijingChina
- University of Chinese Academy of SciencesBeijingChina
| | - Jiaqiang Wang
- State Key Laboratory of Stem Cell and Reproductive BiologyInstitute of ZoologyChinese Academy of SciencesBeijingChina
- Institute for Stem Cell and RegenerationChinese Academy of SciencesBeijingChina
- College of Life ScienceNortheast Agricultural University of ChinaHarbinChina
| | - Ying Zhang
- State Key Laboratory of Stem Cell and Reproductive BiologyInstitute of ZoologyChinese Academy of SciencesBeijingChina
- Institute for Stem Cell and RegenerationChinese Academy of SciencesBeijingChina
| | - Qi Zhou
- State Key Laboratory of Stem Cell and Reproductive BiologyInstitute of ZoologyChinese Academy of SciencesBeijingChina
- Institute for Stem Cell and RegenerationChinese Academy of SciencesBeijingChina
- University of Chinese Academy of SciencesBeijingChina
| | - Wei Li
- School of Life SciencesUniversity of Science and Technology of ChinaHefeiChina
- State Key Laboratory of Stem Cell and Reproductive BiologyInstitute of ZoologyChinese Academy of SciencesBeijingChina
- Institute for Stem Cell and RegenerationChinese Academy of SciencesBeijingChina
- University of Chinese Academy of SciencesBeijingChina
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28
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Fiévet A, Bellanger D, Zahed L, Burglen L, Derrien AC, Dubois d'Enghien C, Lespinasse J, Parfait B, Pedespan JM, Rieunier G, Stoppa-Lyonnet D, Stern MH. DNA repair functional analyses of NBN hypomorphic variants associated with NBN-related infertility. Hum Mutat 2019; 41:608-618. [PMID: 31729086 DOI: 10.1002/humu.23955] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2019] [Revised: 10/17/2019] [Accepted: 11/03/2019] [Indexed: 01/17/2023]
Abstract
Nijmegen breakage syndrome caused by biallelic pathogenic variants of the DNA-damage response gene NBN, is characterized by severe microcephaly, cancer proneness, infertility, and karyotype abnormalities. We previously reported NBN variants in siblings suffering from fertility defects. Here, we identify a new founder NBN variant (c.442A>G, p.(Thr148Ala)) in Lebanese patients associated with isolated infertility. Functional analyses explored preserved or altered functions correlated with their remarkably mild phenotype. Transcript and protein analyses supported the use of an alternative transcript with in-frame skipping of exons 4-5, leading to p84-NBN protein with a preserved forkhead-associated (FHA) domain. The level of NBN was dramatically reduced and the MRN complex delocalized to the cytoplasm. Interestingly, ataxia-elangiectasia mutated (ATM) also shifted from the nucleus to the cytoplasm, suggesting some interaction between ATM and the MRN complex at a steady state. The ATM pathway activation, attenuated in typical patients with NBS, appeared normal under camptothecin treatment in these new NBN-related infertile patients. Cell cycle checkpoint defect was present in these atypical patients, although to a lesser extent than in typical patients with NBS. In conclusion, we report three new NBN-related infertile patients and we suggest that preserved FHA domain could be responsible for the mild phenotype and intermediate DNA-damage response defects.
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Affiliation(s)
- Alice Fiévet
- INSERM U830, Institut Curie, PSL Research University, Paris, France.,D.R.U.M. Team, INSERM U830, Institut Curie, Paris, France.,Service de Génétique, Institut Curie Hôpital, Paris, France.,Service Génétique des Tumeurs, Gustave Roussy, Villejuif, France
| | - Dorine Bellanger
- INSERM U830, Institut Curie, PSL Research University, Paris, France.,D.R.U.M. Team, INSERM U830, Institut Curie, Paris, France
| | - Laila Zahed
- Department of Clinical Laboratory, Saint George Hospital University Medical Center, Beirut, Lebanon
| | - Lydie Burglen
- Centre de Référence des, Malformations et Maladies Congénitales du Cervelet, Paris, France.,GRC n°19, Pathologies Congénitales du Cervelet-LeucoDystrophies, Hôpital Armand Trousseau (APHP), Sorbonne Université, Paris, France.,INSERM U1141, Université Paris Diderot, Paris, France.,Département de Génétique Médicale (GHUEP), Hôpital Armand Trousseau (APHP), Paris, France
| | - Anne-Céline Derrien
- INSERM U830, Institut Curie, PSL Research University, Paris, France.,D.R.U.M. Team, INSERM U830, Institut Curie, Paris, France
| | | | - James Lespinasse
- Génétique Chromosomique, Centre Hospitalier Metropole Savoie, Chambéry-Hôtel-Dieu, Chambéry, France
| | - Béatrice Parfait
- Centre de ressources Biologiques, Hôpital Cochin, Assistance Publique - Hôpitaux de Paris, Paris, France
| | | | - Guillaume Rieunier
- INSERM U830, Institut Curie, PSL Research University, Paris, France.,D.R.U.M. Team, INSERM U830, Institut Curie, Paris, France
| | - Dominique Stoppa-Lyonnet
- D.R.U.M. Team, INSERM U830, Institut Curie, Paris, France.,Service de Génétique, Institut Curie Hôpital, Paris, France.,Université Paris Descartes, Sorbonne-Paris-Cité, Paris, France
| | - Marc-Henri Stern
- INSERM U830, Institut Curie, PSL Research University, Paris, France.,D.R.U.M. Team, INSERM U830, Institut Curie, Paris, France.,Service de Génétique, Institut Curie Hôpital, Paris, France
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29
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Bian L, Meng Y, Zhang M, Li D. MRE11-RAD50-NBS1 complex alterations and DNA damage response: implications for cancer treatment. Mol Cancer 2019; 18:169. [PMID: 31767017 PMCID: PMC6878665 DOI: 10.1186/s12943-019-1100-5] [Citation(s) in RCA: 133] [Impact Index Per Article: 26.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2019] [Accepted: 11/08/2019] [Indexed: 01/26/2023] Open
Abstract
Genome instability is a hallmark of cancer cells and can be accelerated by defects in cellular responses to DNA damage. This feature of malignant cells opens new avenues for tumor targeted therapy. MRE11-RAD50-NBS1 complex plays a crucial role in sensing and repair of DNA damage. Through interacting with other important players of DNA damage response, MRE11-RAD50-NBS1 complex is engaged in various DNA damage repair pathways. Mutations in any member of this complex may lead to hypersensitivity to genotoxic agents and predisposition to malignancy. It is assumed that the defects in the complex may contribute to tumorigenesis and that treatments targeting the defect may be beneficial to cancer patients. Here, we summarized the recent research findings of the role of MRE11-RAD50-NBS1 complex in tumorigenesis, cancer treatment and discussed the potential approaches of targeting this complex to treat cancer.
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Affiliation(s)
- Lei Bian
- Department of Radiation Oncology, Shanghai Ninth People's Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Yiling Meng
- Department of Radiation Oncology, Shanghai Ninth People's Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Meichao Zhang
- Department of Radiation Oncology, Shanghai Ninth People's Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Dong Li
- Department of Radiation Oncology, Shanghai Ninth People's Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China.
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30
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ATM, DNA-PKcs and ATR: shaping development through the regulation of the DNA damage responses. ACTA ACUST UNITED AC 2019. [DOI: 10.1007/s42764-019-00003-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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31
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Fiévet A, Bellanger D, Valence S, Mobuchon L, Afenjar A, Giuliano F, Dubois d'Enghien C, Parfait B, Pedespan JM, Auger N, Rieunier G, Collet A, Burglen L, Stoppa-Lyonnet D, Stern MH. Three new cases of ataxia-telangiectasia-like disorder: No impairment of the ATM pathway, but S-phase checkpoint defect. Hum Mutat 2019; 40:1690-1699. [PMID: 31033087 DOI: 10.1002/humu.23773] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Revised: 04/18/2019] [Accepted: 04/24/2019] [Indexed: 11/09/2022]
Abstract
Ataxia-telangiectasia-like disorder (ATLD) is a rare genomic instability syndrome caused by biallelic variants of MRE11 (meiotic recombination 11) characterized by progressive cerebellar ataxia and typical karyotype abnormalities. These symptoms are common to those of ataxia-telangiectasia, which is consistent with the key role of MRE11 in ataxia-telangiectasia mutated (ATM) activation after DNA double-strand breaks. Three unrelated French patients were referred with ataxia. Only one had typical karyotype abnormalities. Unreported biallelic MRE11 variants were found in these three cases. Interestingly, one variant (c.424G>A) was present in two cases and haplotype analysis strongly suggested a French founder variant. Variants c.544G>A and c.314+4_314+7del lead to splice defects. The level of MRE11 in lymphoblastoid cell lines was consistently and dramatically reduced. Functional consequences were evaluated on activation of the ATM pathway via phosphorylation of ATM targets (KAP1 and CHK2), but no consistent defect was observed. However, an S-phase checkpoint activation defect after camptothecin was observed in these patients with ATLD. In conclusion, we report the first three French ATLD patients and a French founder variant, and propose an S-phase checkpoint activation study to evaluate the pathogenicity of MRE11 variants.
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Affiliation(s)
- Alice Fiévet
- Institut Curie, PSL Research University, Paris, France.,INSERM U830, D.R.U.M. team, Paris, France.,Institut Curie, Hôpital, Service de Génétique, Paris, France
| | - Dorine Bellanger
- Institut Curie, PSL Research University, Paris, France.,INSERM U830, D.R.U.M. team, Paris, France
| | - Stéphanie Valence
- APHP, GHUEP, Hôpital Armand Trousseau, Service de Neurologie Pédiatrique, Paris, France.,Centre de Référence Maladies Rares "Malformations et Maladies Congénitales du Cervelet", Paris-Lyon-Lille, France.,Sorbonne Université, GRC n°19, Pathologies Congénitales du Cervelet-LeucoDystrophies, APHP, Hôpital Armand Trousseau, Paris, France.,INSERM U1141, Université Paris Diderot, Paris, France
| | - Lenha Mobuchon
- Institut Curie, PSL Research University, Paris, France.,INSERM U830, D.R.U.M. team, Paris, France
| | - Alexandra Afenjar
- Centre de Référence Maladies Rares "Malformations et Maladies Congénitales du Cervelet", APHP, Hôpital Armand Trousseau, Paris, France
| | - Fabienne Giuliano
- Service de Génétique Médicale, CHU de Nice, Hôpital l'Archet 2, Nice, France
| | | | - Béatrice Parfait
- Centre de Ressources Biologiques, Hôpital Cochin, Assistance Publique-Hôpitaux de Paris, Paris, France
| | | | - Nathalie Auger
- Department of Biopathology, Gustave Roussy, Villejuif, France
| | - Guillaume Rieunier
- Institut Curie, PSL Research University, Paris, France.,INSERM U830, D.R.U.M. team, Paris, France
| | - Agnès Collet
- Institut Curie, Hôpital, Service de Génétique, Paris, France
| | - Lydie Burglen
- Centre de Référence Maladies Rares "Malformations et Maladies Congénitales du Cervelet", Paris-Lyon-Lille, France.,Sorbonne Université, GRC n°19, Pathologies Congénitales du Cervelet-LeucoDystrophies, APHP, Hôpital Armand Trousseau, Paris, France.,INSERM U1141, Université Paris Diderot, Paris, France.,Département de Génétique Médicale, APHP, GHUEP, Hôpital Armand Trousseau, Paris, France
| | - Dominique Stoppa-Lyonnet
- INSERM U830, D.R.U.M. team, Paris, France.,Institut Curie, Hôpital, Service de Génétique, Paris, France.,Faculté de Médecine, Université Paris-Descartes, Paris, France
| | - Marc-Henri Stern
- Institut Curie, PSL Research University, Paris, France.,INSERM U830, D.R.U.M. team, Paris, France.,Institut Curie, Hôpital, Service de Génétique, Paris, France
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32
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Tucker EJ, Grover SR, Robevska G, van den Bergen J, Hanna C, Sinclair AH. Identification of variants in pleiotropic genes causing "isolated" premature ovarian insufficiency: implications for medical practice. Eur J Hum Genet 2018; 26:1319-1328. [PMID: 29706645 PMCID: PMC6117257 DOI: 10.1038/s41431-018-0140-4] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2017] [Revised: 02/25/2018] [Accepted: 03/13/2018] [Indexed: 11/09/2022] Open
Abstract
Next-generation sequencing (NGS) is increasingly being used in a clinical setting for the molecular diagnosis of patients with heterogeneous disorders, such as premature ovarian insufficiency (POI). We performed NGS of ~1000 candidate genes in four unrelated patients with POI. We discovered the genetic cause of "isolated" POI in two cases, both of which had causative variants in surprising genes. In the first case, a homozygous nonsense variant in NBN was causative. Recessive function-altering NBN variants typically cause Nijmegen breakage syndrome characterized by microcephaly, cancer predisposition, and immunodeficiency, none of which are evident in the patient. At a cellular level, we found evidence of chromosomal instability. In the second case, compound heterozygous variants in EIF2B2 were causative. Recessive EIF2B2 function-altering variants usually cause leukoencephalopathy with episodic decline. Subsequent MRI revealed subclinical neurological abnormalities. These cases demonstrate that variants in NBN and EIF2B2, which usually cause severe syndromes, can cause apparently isolated POI, and that (1) NGS can precede clinical diagnosis and guide patient management, (2) NGS can redefine the phenotypic spectrum of syndromes, and (3) NGS may make unanticipated diagnoses that must be sensitively communicated to patients. Although there is rigorous debate about the handling of secondary/incidental findings using NGS, there is little discussion of the management of causative pleiotropic gene variants that have broader implications than that for which genetic studies were sought.
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Affiliation(s)
- Elena J Tucker
- Murdoch Children's Research Institute, Royal Children's Hospital, Melbourne, VIC, 3052, Australia
- Department of Paediatrics, University of Melbourne, Melbourne, VIC, 3052, Australia
| | - Sonia R Grover
- Murdoch Children's Research Institute, Royal Children's Hospital, Melbourne, VIC, 3052, Australia
- Department of Paediatrics, University of Melbourne, Melbourne, VIC, 3052, Australia
- Department of Paediatric and Adolescent Gynaecology, Royal Children's Hospital, Melbourne, VIC, 3052, Australia
| | - Gorjana Robevska
- Murdoch Children's Research Institute, Royal Children's Hospital, Melbourne, VIC, 3052, Australia
| | - Jocelyn van den Bergen
- Murdoch Children's Research Institute, Royal Children's Hospital, Melbourne, VIC, 3052, Australia
| | - Chloe Hanna
- Murdoch Children's Research Institute, Royal Children's Hospital, Melbourne, VIC, 3052, Australia
- Department of Paediatric and Adolescent Gynaecology, Royal Children's Hospital, Melbourne, VIC, 3052, Australia
| | - Andrew H Sinclair
- Murdoch Children's Research Institute, Royal Children's Hospital, Melbourne, VIC, 3052, Australia.
- Department of Paediatrics, University of Melbourne, Melbourne, VIC, 3052, Australia.
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MRE11 inhibition highlights a replication stress-dependent vulnerability of MYCN-driven tumors. Cell Death Dis 2018; 9:895. [PMID: 30166519 PMCID: PMC6117286 DOI: 10.1038/s41419-018-0924-z] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Revised: 07/18/2018] [Accepted: 07/20/2018] [Indexed: 12/12/2022]
Abstract
MRE11 is a component of the MRE11/RAD50/NBS1 (MRN) complex, whose activity is essential to control faithful DNA replication and to prevent accumulation of deleterious DNA double-strand breaks. In humans, hypomorphic mutations in these genes lead to DNA damage response (DDR)-defective and cancer-prone syndromes. Moreover, MRN complex dysfunction dramatically affects the nervous system, where MRE11 is required to restrain MYCN-dependent replication stress, during the rapid expansion of progenitor cells. MYCN activation, often due to genetic amplification, represents the driving oncogenic event for a number of human tumors, conferring bad prognosis and predicting very poor responses even to the most aggressive therapeutic protocols. This is prototypically exemplified by neuroblastoma, where MYCN amplification occurs in about 25% of the cases. Intriguingly, MRE11 is highly expressed and predicts bad prognosis in MYCN-amplified neuroblastoma. Due to the lack of direct means to target MYCN, we explored the possibility to trigger intolerable levels of replication stress-dependent DNA damage, by inhibiting MRE11 in MYCN-amplified preclinical models. Indeed, either MRE11 knockdown or its pharmacological inhibitor mirin induce accumulation of replication stress and DNA damage biomarkers in MYCN-amplified cells. The consequent DDR recruits p53 and promotes a p53-dependent cell death, as indicated by p53 loss- and gain-of-function experiments. Encapsulation of mirin in nanoparticles allowed its use on MYCN-amplified neuroblastoma xenografts in vivo, which resulted in a sharp impairment of tumor growth, associated with DDR activation, p53 accumulation, and cell death. Therefore, we propose that MRE11 inhibition might be an effective strategy to treat MYCN-amplified and p53 wild-type neuroblastoma, and suggest that targeting replication stress with appropriate tools should be further exploited to tackle MYCN-driven tumors.
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The Major Tegument Protein of Bovine Herpesvirus 1, VP8, Interacts with DNA Damage Response Proteins and Induces Apoptosis. J Virol 2018; 92:JVI.00773-18. [PMID: 29769345 DOI: 10.1128/jvi.00773-18] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Accepted: 05/11/2018] [Indexed: 12/17/2022] Open
Abstract
VP8, the UL47 gene product in bovine herpesvirus-1 (BoHV-1), is a major tegument protein that is essential for virus replication in vivo The major DNA damage response protein, ataxia telangiectasia mutated (ATM), phosphorylates Nijmegen breakage syndrome (NBS1) and structural maintenance of chromosome-1 (SMC1) proteins during the DNA damage response. VP8 was found to interact with ATM and NBS1 during transfection and BoHV-1 infection. However, VP8 did not interfere with phosphorylation of ATM in transfected or BoHV-1-infected cells. In contrast, VP8 inhibited phosphorylation of both NBS1 and SMC1 in transfected cells, as well as in BoHV-1-infected cells, but not in cells infected with a VP8 deletion mutant (BoHV-1ΔUL47). Inhibition of NBS1 and SMC1 phosphorylation was observed at 4 h postinfection by nuclear VP8. Furthermore, UV light-induced cyclobutane pyrimidine dimer (CPD) repair was reduced in the presence of VP8, and VP8 in fact enhanced etoposide or UV-induced apoptosis. This suggests that VP8 blocks the ATM/NBS1/SMC1 pathway and inhibits DNA repair. VP8 induced apoptosis in VP8-transfected cells through caspase-3 activation. The fact that BoHV-1 is known to induce apoptosis through caspase-3 activation is in agreement with this observation. The role of VP8 was confirmed by the observation that BoHV-1 induced significantly more apoptosis than BoHV-1ΔUL47. These data reveal a potential role of VP8 in the modulation of the DNA damage response pathway and induction of apoptosis during BoHV-1 infection.IMPORTANCE To our knowledge, the effect of BoHV-1 infection on the DNA damage response has not been characterized. Since BoHV-1ΔUL47 was previously shown to be avirulent in vivo, VP8 is critical for the progression of viral infection. We demonstrated that VP8 interacts with DNA damage response proteins and disrupts the ATM-NBS1-SMC1 pathway by inhibiting phosphorylation of DNA repair proteins NBS1 and SMC1. Furthermore, interference of VP8 with DNA repair was correlated with decreased cell viability and increased DNA damage-induced apoptosis. These data show that BoHV-1 VP8 developed a novel strategy to interrupt the ATM signaling pathway and to promote apoptosis. These results further enhance our understanding of the functions of VP8 during BoHV-1 infection and provide an additional explanation for the reduced virulence of BoHV-1ΔUL47.
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35
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Hartlerode AJ, Regal JA, Ferguson DO. Reversible mislocalization of a disease-associated MRE11 splice variant product. Sci Rep 2018; 8:10121. [PMID: 29973640 PMCID: PMC6031676 DOI: 10.1038/s41598-018-28370-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Accepted: 06/20/2018] [Indexed: 01/13/2023] Open
Abstract
Ataxia-telangiectasia (AT) and related disorders feature cancer predisposition, neurodegeneration, and immunodeficiency resulting from failure to respond to DNA damage. Hypomorphic mutations in MRE11 cause an AT-like disorder (ATLD) with variable clinical presentation. We have sought to understand how diverse MRE11 mutations may provide unique therapeutic opportunities, and potentially correlate with clinical variability. Here we have undertaken studies of an MRE11 splice site mutation that was found in two ATLD siblings that died of pulmonary adenocarcinoma at the young ages of 9 and 16. The mutation, termed MRE11 alternative splice mutation (MRE11ASM), causes skipping of a highly conserved exon while preserving the protein's open reading frame. A new mouse model expressing Mre11ASM from the endogenous locus demonstrates that the protein is present at very low levels, a feature in common with the MRE11ATLD1 mutant found in other patients. However, the mechanisms causing low protein levels are distinct. MRE11ASM is mislocalized to the cytoplasm, in contrast to MRE11ATLD1, which remains nuclear. Strikingly, MRE11ASM mislocalization is corrected by inhibition of the proteasome, implying that the protein undergoes strict protein quality control in the nucleus. These findings raise the prospect that inhibition of poorly understood nuclear protein quality control mechanisms might have therapeutic benefit in genetic disorders causing cytoplasmic mislocalization.
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Affiliation(s)
- Andrea J Hartlerode
- Department of Pathology, The University of Michigan Medical School, Ann Arbor, MI, 48109-2200, USA
| | - Joshua A Regal
- Department of Pathology, The University of Michigan Medical School, Ann Arbor, MI, 48109-2200, USA
- Molecular and Cellular Pathology Graduate Program, The University of Michigan Medical School, Ann Arbor, MI, 48109-2200, USA
| | - David O Ferguson
- Department of Pathology, The University of Michigan Medical School, Ann Arbor, MI, 48109-2200, USA.
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36
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Genome instability syndromes caused by impaired DNA repair and aberrant DNA damage responses. Cell Biol Toxicol 2018; 34:337-350. [DOI: 10.1007/s10565-018-9429-x] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2018] [Accepted: 03/25/2018] [Indexed: 11/25/2022]
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37
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SbcC-SbcD and ExoI process convergent forks to complete chromosome replication. Proc Natl Acad Sci U S A 2017; 115:349-354. [PMID: 29208713 DOI: 10.1073/pnas.1715960114] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
SbcC-SbcD are the bacterial orthologs of Mre11-Rad50, a nuclease complex essential for genome stability, normal development, and viability in mammals. In vitro, these enzymes degrade long DNA palindromic structures. When inactivated along with ExoI in Escherichia coli, or Sae2 in eukaryotes, palindromic amplifications arise and propagate in cells. However, long DNA palindromes are not normally found in bacterial or human genomes, leaving the cellular substrates and function of these enzymes unknown. Here, we show that during the completion of DNA replication, convergent replication forks form a palindrome-like structural intermediate that requires nucleolytic processing by SbcC-SbcD and ExoI before chromosome replication can be completed. Inactivation of these nucleases prevents completion from occurring, and under these conditions, cells maintain viability by shunting the reaction through an aberrant recombinational pathway that leads to amplifications and instability in this region. The results identify replication completion as an event critical to maintain genome integrity and cell viability, demonstrate SbcC-SbcD-ExoI acts before RecBCD and is required to initiate the completion reaction, and reveal how defects in completion result in genomic instability.
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38
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Spehalski E, Capper KM, Smith CJ, Morgan MJ, Dinkelmann M, Buis J, Sekiguchi JM, Ferguson DO. MRE11 Promotes Tumorigenesis by Facilitating Resistance to Oncogene-Induced Replication Stress. Cancer Res 2017; 77:5327-5338. [PMID: 28819025 DOI: 10.1158/0008-5472.can-17-1355] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2017] [Revised: 07/12/2017] [Accepted: 07/28/2017] [Indexed: 01/09/2023]
Abstract
Hypomorphic mutations in the genes encoding the MRE11/RAD50/NBS1 (MRN) DNA repair complex lead to cancer-prone syndromes. MRN binds DNA double-strand breaks, where it functions in repair and triggers cell-cycle checkpoints via activation of the ataxia-telangiectasia mutated kinase. To gain understanding of MRN in cancer, we engineered mice with B lymphocytes lacking MRN, or harboring MRN in which MRE11 lacks nuclease activities. Both forms of MRN deficiency led to hallmarks of cancer, including oncogenic translocations involving c-Myc and the immunoglobulin locus. These preneoplastic B lymphocytes did not progress to detectable B lineage lymphoma, even in the absence of p53. Moreover, Mre11 deficiencies prevented tumorigenesis in a mouse model strongly predisposed to spontaneous B-cell lymphomas. Our findings indicate that MRN cannot be considered a standard tumor suppressor and instead imply that nuclease activities of MRE11 are required for oncogenesis. Inhibition of MRE11 nuclease activity increased DNA damage and selectively induced apoptosis in cells overexpressing oncogenes, suggesting MRE11 serves an important role in countering oncogene-induced replication stress. Thus, MRE11 may offer a target for cancer therapeutic development. More broadly, our work supports the idea that subtle enhancements of endogenous genome instability can exceed the tolerance of cancer cells and be exploited for therapeutic ends. Cancer Res; 77(19); 5327-38. ©2017 AACR.
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Affiliation(s)
- Elizabeth Spehalski
- Department of Pathology, The University of Michigan Medical School, Ann Arbor, Michigan.,Molecular and Cellular Pathology Graduate Program, The University of Michigan Medical School, Ann Arbor, Michigan
| | - Kayla M Capper
- Cancer Biology Graduate Program, The University of Michigan Medical School, Ann Arbor, Michigan
| | - Cheryl J Smith
- Department of Human Genetics, The University of Michigan Medical School, Ann Arbor, Michigan
| | - Mary J Morgan
- Department of Pathology, The University of Michigan Medical School, Ann Arbor, Michigan.,Molecular and Cellular Pathology Graduate Program, The University of Michigan Medical School, Ann Arbor, Michigan
| | - Maria Dinkelmann
- Department of Pathology, The University of Michigan Medical School, Ann Arbor, Michigan
| | - Jeffrey Buis
- Department of Pathology, The University of Michigan Medical School, Ann Arbor, Michigan
| | - JoAnn M Sekiguchi
- Department of Human Genetics, The University of Michigan Medical School, Ann Arbor, Michigan. .,Department of Internal Medicine, The University of Michigan Medical School, Ann Arbor, Michigan
| | - David O Ferguson
- Department of Pathology, The University of Michigan Medical School, Ann Arbor, Michigan.
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39
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Tsukagoshi M, Araki K, Yokobori T, Altan B, Suzuki H, Kubo N, Watanabe A, Ishii N, Hosouchi Y, Nishiyama M, Shirabe K, Kuwano H. Overexpression of karyopherin-α2 in cholangiocarcinoma correlates with poor prognosis and gemcitabine sensitivity via nuclear translocation of DNA repair proteins. Oncotarget 2017; 8:42159-42172. [PMID: 28178675 PMCID: PMC5522057 DOI: 10.18632/oncotarget.15020] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Accepted: 01/04/2017] [Indexed: 01/07/2023] Open
Abstract
Cholangiocarcinoma is a highly malignant tumor, and the development of new therapeutic strategies is critical. Karyopherin-α2 (KPNA2) functions as an adaptor that mediates nucleocytoplasmic transport. Specifically, KPNA2 transports one of the important DNA repair machineries, the MRE11-RAD50-NBS1 (MRN) complex, to the nucleus. In this study, we clarified the significance of KPNA2 in cholangiocarcinoma. KPNA2 expression evaluated by immunohistochemical analysis was common in malignant tissue but rare in adjacent noncancerous tissues. KPNA2 overexpression was significantly correlated with poor prognosis and was an independent prognostic factor after surgery. In patients with cholangiocarcinoma who received gemcitabine after surgery, KPNA2 overexpression tended to be a prognostic indicator of poor overall survival. In KPNA2-depleted cholangiocarcinoma cells, proliferation was significantly decreased and gemcitabine sensitivity was enhanced in vitro and in vivo. Expression of KPNA2 and the MRN complex displayed colocalization in the nucleus. In addition, nuclear localization of the MRN complex was regulated by KPNA2 in vitro. These results suggest that KPNA2 expression may be a useful prognostic and predictive marker of gemcitabine sensitivity and survival. The regulation of KPNA2 expression may be a new therapeutic strategy for cholangiocarcinoma.
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Affiliation(s)
- Mariko Tsukagoshi
- 1 Department of General Surgical Science, Gunma University Graduate School of Medicine, Maebashi, Gunma 371-8511, Japan
- 3 Division of Hepatobiliary and Pancreatic Surgery, Integrative Center of General Surgery, Gunma University Hospital, Maebashi, Gunma 371-8511, Japan
| | - Kenichiro Araki
- 1 Department of General Surgical Science, Gunma University Graduate School of Medicine, Maebashi, Gunma 371-8511, Japan
- 3 Division of Hepatobiliary and Pancreatic Surgery, Integrative Center of General Surgery, Gunma University Hospital, Maebashi, Gunma 371-8511, Japan
| | - Takehiko Yokobori
- 4 Department of Molecular Pharmacology and Oncology, Gunma University Graduate School of Medicine, Maebashi, Gunma 371-8511, Japan
| | - Bolag Altan
- 1 Department of General Surgical Science, Gunma University Graduate School of Medicine, Maebashi, Gunma 371-8511, Japan
| | - Hideki Suzuki
- 1 Department of General Surgical Science, Gunma University Graduate School of Medicine, Maebashi, Gunma 371-8511, Japan
| | - Norio Kubo
- 1 Department of General Surgical Science, Gunma University Graduate School of Medicine, Maebashi, Gunma 371-8511, Japan
- 3 Division of Hepatobiliary and Pancreatic Surgery, Integrative Center of General Surgery, Gunma University Hospital, Maebashi, Gunma 371-8511, Japan
| | - Akira Watanabe
- 1 Department of General Surgical Science, Gunma University Graduate School of Medicine, Maebashi, Gunma 371-8511, Japan
- 3 Division of Hepatobiliary and Pancreatic Surgery, Integrative Center of General Surgery, Gunma University Hospital, Maebashi, Gunma 371-8511, Japan
| | - Norihiro Ishii
- 1 Department of General Surgical Science, Gunma University Graduate School of Medicine, Maebashi, Gunma 371-8511, Japan
| | - Yasuo Hosouchi
- 5 Department of Surgery and Laparoscopic Surgery, Gunma Prefecture Saiseikai-Maebashi Hospital, Maebashi, Gunma 371-0821, Japan
| | - Masahiko Nishiyama
- 4 Department of Molecular Pharmacology and Oncology, Gunma University Graduate School of Medicine, Maebashi, Gunma 371-8511, Japan
| | - Ken Shirabe
- 2 Department of Hepatobiliary and Pancreatic Surgery, Gunma University Graduate School of Medicine, Maebashi, Gunma 371-8511, Japan
- 3 Division of Hepatobiliary and Pancreatic Surgery, Integrative Center of General Surgery, Gunma University Hospital, Maebashi, Gunma 371-8511, Japan
| | - Hiroyuki Kuwano
- 1 Department of General Surgical Science, Gunma University Graduate School of Medicine, Maebashi, Gunma 371-8511, Japan
- 3 Division of Hepatobiliary and Pancreatic Surgery, Integrative Center of General Surgery, Gunma University Hospital, Maebashi, Gunma 371-8511, Japan
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40
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Abstract
Multiple DNA repair pathways maintain genome stability and ensure that DNA remains essentially unchanged over the life of a cell. Various human diseases occur if DNA repair is compromised, and most of these impact the nervous system, in some cases exclusively. However, it is often unclear what specific endogenous damage underpins disease pathology. Generally, the types of causative DNA damage are associated with replication, transcription, or oxidative metabolism; other direct sources of endogenous lesions may arise from aberrant topoisomerase activity or ribonucleotide incorporation into DNA. This review focuses on the etiology of DNA damage in the nervous system and the genome stability pathways that prevent human neurologic disease.
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Affiliation(s)
- Peter J McKinnon
- Department of Genetics, St Jude Children's Research Hospital, Memphis, Tennessee 38105, USA
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41
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Deshpande RA, Lee JH, Paull TT. Rad50 ATPase activity is regulated by DNA ends and requires coordination of both active sites. Nucleic Acids Res 2017; 45:5255-5268. [PMID: 28369545 PMCID: PMC5435944 DOI: 10.1093/nar/gkx173] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2016] [Revised: 03/02/2017] [Accepted: 03/06/2017] [Indexed: 01/03/2023] Open
Abstract
The Mre11-Rad50-Nbs1(Xrs2) (MRN/X) complex is critical for the repair and signaling of DNA double strand breaks. The catalytic core of MRN/X comprised of the Mre11 nuclease and Rad50 adenosine triphosphatase (ATPase) active sites dimerizes through association between the Rad50 ATPase catalytic domains and undergoes extensive conformational changes upon ATP binding. This ATP-bound 'closed' state promotes binding to DNA, tethering DNA ends and ATM activation, but prevents nucleolytic processing of DNA ends, while ATP hydrolysis is essential for Mre11 endonuclease activity at blocked DNA ends. Here we investigate the regulation of ATP hydrolysis as well as the interdependence of the two functional active sites. We find that double-stranded DNA stimulates ATP hydrolysis by hMRN over ∼20-fold in an end-dependent manner. Using catalytic site mutants to create Rad50 dimers with only one functional ATPase site, we find that both ATPase sites are required for the stimulation by DNA. MRN-mediated endonucleolytic cleavage of DNA at sites of protein adducts requires ATP hydrolysis at both sites, as does the stimulation of ATM kinase activity. These observations suggest that symmetrical engagement of the Rad50 catalytic head domains with ATP bound at both sites is important for MRN functions in eukaryotic cells.
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Affiliation(s)
- Rajashree A. Deshpande
- Howard Hughes Medical Institute, Department of Molecular Biosciences, Institute for Cellular and Molecular Biology, University of Texas at Austin, Austin, TX 78712, USA
| | - Ji-Hoon Lee
- Howard Hughes Medical Institute, Department of Molecular Biosciences, Institute for Cellular and Molecular Biology, University of Texas at Austin, Austin, TX 78712, USA
| | - Tanya T. Paull
- Howard Hughes Medical Institute, Department of Molecular Biosciences, Institute for Cellular and Molecular Biology, University of Texas at Austin, Austin, TX 78712, USA
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42
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SHPRH regulates rRNA transcription by recognizing the histone code in an mTOR-dependent manner. Proc Natl Acad Sci U S A 2017; 114:E3424-E3433. [PMID: 28400511 DOI: 10.1073/pnas.1701978114] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Many DNA repair proteins have additional functions other than their roles in DNA repair. In addition to catalyzing PCNA polyubiquitylation in response to the stalling of DNA replication, SHPRH has the additional function of facilitating rRNA transcription by localizing to the ribosomal DNA (rDNA) promoter in the nucleoli. SHPRH was recruited to the rDNA promoter using its plant homeodomain (PHD), which interacts with histone H3 when the fourth lysine of H3 is not trimethylated. SHPRH enrichment at the rDNA promoter was inhibited by cell starvation, by treatment with actinomycin D or rapamycin, or by depletion of CHD4. SHPRH also physically interacted with the RNA polymerase I complex. Taken together, we provide evidence that SHPRH functions in rRNA transcription through its interaction with histone H3 in a mammalian target of rapamycin (mTOR)-dependent manner.
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43
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Merigliano C, Marzio A, Renda F, Somma MP, Gatti M, Vernì F. A Role for the Twins Protein Phosphatase (PP2A-B55) in the Maintenance of Drosophila Genome Integrity. Genetics 2017; 205:1151-1167. [PMID: 28040742 PMCID: PMC5340330 DOI: 10.1534/genetics.116.192781] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Accepted: 12/21/2016] [Indexed: 01/14/2023] Open
Abstract
The protein phosphatase 2A (PP2A) is a conserved heterotrimeric enzyme that regulates several cellular processes including the DNA damage response and mitosis. Consistent with these functions, PP2A is mutated in many types of cancer and acts as a tumor suppressor. In mammalian cells, PP2A inhibition results in DNA double strand breaks (DSBs) and chromosome aberrations (CABs). However, the mechanisms through which PP2A prevents DNA damage are still unclear. Here, we focus on the role of the Drosophila twins (tws) gene in the maintenance of chromosome integrity; tws encodes the B regulatory subunit (B/B55) of PP2A. Mutations in tws cause high frequencies of CABs (0.5 CABs/cell) in Drosophila larval brain cells and lead to an abnormal persistence of γ-H2Av repair foci. However, mutations that disrupt the PP4 phosphatase activity impair foci dissolution but do not cause CABs, suggesting that a delayed foci regression is not clastogenic. We also show that Tws is required for activation of the G2/M DNA damage checkpoint while PP4 is required for checkpoint recovery, a result that points to a conserved function of these phosphatases from flies to humans. Mutations in the ATM-coding gene tefu are strictly epistatic to tws mutations for the CAB phenotype, suggesting that failure to dephosphorylate an ATM substrate(s) impairs DNA DSBs repair. In addition, mutations in the Ku70 gene, which do not cause CABs, completely suppress CAB formation in tws Ku70 double mutants. These results suggest the hypothesis that an improperly phosphorylated Ku70 protein can lead to DNA damage and CABs.
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Affiliation(s)
- Chiara Merigliano
- Dipartimento di Biologia e Biotecnologie "C. Darwin," Sapienza, Università di Roma, 00185, Italy
| | - Antonio Marzio
- Dipartimento di Biologia e Biotecnologie "C. Darwin," Sapienza, Università di Roma, 00185, Italy
| | - Fioranna Renda
- Dipartimento di Biologia e Biotecnologie "C. Darwin," Sapienza, Università di Roma, 00185, Italy
| | - Maria Patrizia Somma
- Istituto di Biologia e Patologia Molecolari del Consiglio Nazionale delle Ricerche, Sapienza, Università di Roma, 00185, Italy
| | - Maurizio Gatti
- Dipartimento di Biologia e Biotecnologie "C. Darwin," Sapienza, Università di Roma, 00185, Italy
- Istituto di Biologia e Patologia Molecolari del Consiglio Nazionale delle Ricerche, Sapienza, Università di Roma, 00185, Italy
| | - Fiammetta Vernì
- Dipartimento di Biologia e Biotecnologie "C. Darwin," Sapienza, Università di Roma, 00185, Italy
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44
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Tucker EJ, Grover SR, Bachelot A, Touraine P, Sinclair AH. Premature Ovarian Insufficiency: New Perspectives on Genetic Cause and Phenotypic Spectrum. Endocr Rev 2016; 37:609-635. [PMID: 27690531 DOI: 10.1210/er.2016-1047] [Citation(s) in RCA: 140] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Premature ovarian insufficiency (POI) is one form of female infertility, defined by loss of ovarian activity before the age of 40 and characterized by amenorrhea (primary or secondary) with raised gonadotropins and low estradiol. POI affects up to one in 100 females, including one in 1000 before the age of 30. Substantial evidence suggests a genetic basis for POI; however, the majority of cases remain unexplained, indicating that genes likely to be associated with this condition are yet to be discovered. This review discusses the current knowledge of the genetic basis of POI. We highlight genes typically known to cause syndromic POI that can be responsible for isolated POI. The role of mouse models in understanding POI pathogenesis is discussed, and a thorough list of candidate POI genes is provided. Identifying a genetic basis for POI has multiple advantages, such as enabling the identification of presymptomatic family members who can be offered counseling and cryopreservation of eggs before depletion, enabling personalized treatment based on the cause of an individual's condition, and providing better understanding of disease mechanisms that ultimately aid the development of improved treatments.
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Affiliation(s)
- Elena J Tucker
- Murdoch Children's Research Institute (E.J.T., S.R.G., A.H.S.), Royal Children's Hospital, Melbourne, VIC 3052 Australia; Department of Paediatrics (E.J.T., S.R.G., A.H.S.), University of Melbourne, Melbourne, VIC 3010, Australia; Department of Paediatric and Adolescent Gynaecology (S.R.G.), Royal Children's Hospital, Melbourne, VIC 3052, Australia; Assistance Publique Hôpitaux de Paris, (A.B., P.T.), IE3M, Université Pierre et Marie Curie, Paris 6 University, Department of Endocrinology and Reproductive Medicine, Centre de Référence des Maladies Endocriniennes Rares de la Croissance et des Pathologies Gynécologiques Rares, Pitié-Salpêtrière Hospital, Université Pierre et Marie Curie, 75013 Paris, France; Institut National de la Santé et de la Recherche Médicale (A.B., P.T.), 75654 Paris, France
| | - Sonia R Grover
- Murdoch Children's Research Institute (E.J.T., S.R.G., A.H.S.), Royal Children's Hospital, Melbourne, VIC 3052 Australia; Department of Paediatrics (E.J.T., S.R.G., A.H.S.), University of Melbourne, Melbourne, VIC 3010, Australia; Department of Paediatric and Adolescent Gynaecology (S.R.G.), Royal Children's Hospital, Melbourne, VIC 3052, Australia; Assistance Publique Hôpitaux de Paris, (A.B., P.T.), IE3M, Université Pierre et Marie Curie, Paris 6 University, Department of Endocrinology and Reproductive Medicine, Centre de Référence des Maladies Endocriniennes Rares de la Croissance et des Pathologies Gynécologiques Rares, Pitié-Salpêtrière Hospital, Université Pierre et Marie Curie, 75013 Paris, France; Institut National de la Santé et de la Recherche Médicale (A.B., P.T.), 75654 Paris, France
| | - Anne Bachelot
- Murdoch Children's Research Institute (E.J.T., S.R.G., A.H.S.), Royal Children's Hospital, Melbourne, VIC 3052 Australia; Department of Paediatrics (E.J.T., S.R.G., A.H.S.), University of Melbourne, Melbourne, VIC 3010, Australia; Department of Paediatric and Adolescent Gynaecology (S.R.G.), Royal Children's Hospital, Melbourne, VIC 3052, Australia; Assistance Publique Hôpitaux de Paris, (A.B., P.T.), IE3M, Université Pierre et Marie Curie, Paris 6 University, Department of Endocrinology and Reproductive Medicine, Centre de Référence des Maladies Endocriniennes Rares de la Croissance et des Pathologies Gynécologiques Rares, Pitié-Salpêtrière Hospital, Université Pierre et Marie Curie, 75013 Paris, France; Institut National de la Santé et de la Recherche Médicale (A.B., P.T.), 75654 Paris, France
| | - Philippe Touraine
- Murdoch Children's Research Institute (E.J.T., S.R.G., A.H.S.), Royal Children's Hospital, Melbourne, VIC 3052 Australia; Department of Paediatrics (E.J.T., S.R.G., A.H.S.), University of Melbourne, Melbourne, VIC 3010, Australia; Department of Paediatric and Adolescent Gynaecology (S.R.G.), Royal Children's Hospital, Melbourne, VIC 3052, Australia; Assistance Publique Hôpitaux de Paris, (A.B., P.T.), IE3M, Université Pierre et Marie Curie, Paris 6 University, Department of Endocrinology and Reproductive Medicine, Centre de Référence des Maladies Endocriniennes Rares de la Croissance et des Pathologies Gynécologiques Rares, Pitié-Salpêtrière Hospital, Université Pierre et Marie Curie, 75013 Paris, France; Institut National de la Santé et de la Recherche Médicale (A.B., P.T.), 75654 Paris, France
| | - Andrew H Sinclair
- Murdoch Children's Research Institute (E.J.T., S.R.G., A.H.S.), Royal Children's Hospital, Melbourne, VIC 3052 Australia; Department of Paediatrics (E.J.T., S.R.G., A.H.S.), University of Melbourne, Melbourne, VIC 3010, Australia; Department of Paediatric and Adolescent Gynaecology (S.R.G.), Royal Children's Hospital, Melbourne, VIC 3052, Australia; Assistance Publique Hôpitaux de Paris, (A.B., P.T.), IE3M, Université Pierre et Marie Curie, Paris 6 University, Department of Endocrinology and Reproductive Medicine, Centre de Référence des Maladies Endocriniennes Rares de la Croissance et des Pathologies Gynécologiques Rares, Pitié-Salpêtrière Hospital, Université Pierre et Marie Curie, 75013 Paris, France; Institut National de la Santé et de la Recherche Médicale (A.B., P.T.), 75654 Paris, France
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Staples CJ, Barone G, Myers KN, Ganesh A, Gibbs-Seymour I, Patil AA, Beveridge RD, Daye C, Beniston R, Maslen S, Ahel I, Skehel JM, Collis SJ. MRNIP/C5orf45 Interacts with the MRN Complex and Contributes to the DNA Damage Response. Cell Rep 2016; 16:2565-2575. [PMID: 27568553 PMCID: PMC5014761 DOI: 10.1016/j.celrep.2016.07.087] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2015] [Revised: 05/25/2016] [Accepted: 07/27/2016] [Indexed: 11/27/2022] Open
Abstract
Through an RNAi-based screen for previously uncharacterized regulators of genome stability, we have identified the human protein C5orf45 as an important factor in preventing the accumulation of DNA damage in human cells. Here, we functionally characterize C5orf45 as a binding partner of the MRE11-RAD50-NBS1 (MRN) damage-sensing complex. Hence, we rename C5orf45 as MRNIP for MRN-interacting protein (MRNIP). We find that MRNIP is rapidly recruited to sites of DNA damage. Cells depleted of MRNIP display impaired chromatin loading of the MRN complex, resulting in reduced DNA end resection and defective ATM-mediated DNA damage signaling, a reduced ability to repair DNA breaks, and radiation sensitivity. Finally, we show that MRNIP phosphorylation on serine 115 leads to its nuclear localization, and this modification is required for MRNIP's role in promoting genome stability. Collectively, these data reveal that MRNIP is an important component of the human DNA damage response.
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Affiliation(s)
- Christopher J Staples
- Sheffield Institute for Nucleic Acids (SInFoNiA), Department of Oncology and Metabolism, Academic Unit of Molecular Oncology, University of Sheffield Medical School, Beech Hill Road, Sheffield S10 2RX, UK
| | - Giancarlo Barone
- Sheffield Institute for Nucleic Acids (SInFoNiA), Department of Oncology and Metabolism, Academic Unit of Molecular Oncology, University of Sheffield Medical School, Beech Hill Road, Sheffield S10 2RX, UK
| | - Katie N Myers
- Sheffield Institute for Nucleic Acids (SInFoNiA), Department of Oncology and Metabolism, Academic Unit of Molecular Oncology, University of Sheffield Medical School, Beech Hill Road, Sheffield S10 2RX, UK
| | - Anil Ganesh
- Sheffield Institute for Nucleic Acids (SInFoNiA), Department of Oncology and Metabolism, Academic Unit of Molecular Oncology, University of Sheffield Medical School, Beech Hill Road, Sheffield S10 2RX, UK
| | - Ian Gibbs-Seymour
- Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, UK
| | - Abhijit A Patil
- Sheffield Institute for Nucleic Acids (SInFoNiA), Department of Oncology and Metabolism, Academic Unit of Molecular Oncology, University of Sheffield Medical School, Beech Hill Road, Sheffield S10 2RX, UK
| | - Ryan D Beveridge
- Sheffield Institute for Nucleic Acids (SInFoNiA), Department of Oncology and Metabolism, Academic Unit of Molecular Oncology, University of Sheffield Medical School, Beech Hill Road, Sheffield S10 2RX, UK
| | - Caroline Daye
- Sheffield Institute for Nucleic Acids (SInFoNiA), Department of Oncology and Metabolism, Academic Unit of Molecular Oncology, University of Sheffield Medical School, Beech Hill Road, Sheffield S10 2RX, UK
| | - Richard Beniston
- Biological Mass Spectrometry Facility biOMICS, University of Sheffield, Brook Hill Road, Sheffield S3 7HF, UK
| | - Sarah Maslen
- Division of Cell Biology, Mass Spectrometry Group, The MRC Laboratory of Molecular Biology, Hills Road, Cambridge CB2 0QH, UK
| | - Ivan Ahel
- Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, UK
| | - J Mark Skehel
- Division of Cell Biology, Mass Spectrometry Group, The MRC Laboratory of Molecular Biology, Hills Road, Cambridge CB2 0QH, UK
| | - Spencer J Collis
- Sheffield Institute for Nucleic Acids (SInFoNiA), Department of Oncology and Metabolism, Academic Unit of Molecular Oncology, University of Sheffield Medical School, Beech Hill Road, Sheffield S10 2RX, UK.
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Halevy T, Akov S, Bohndorf M, Mlody B, Adjaye J, Benvenisty N, Goldberg M. Chromosomal Instability and Molecular Defects in Induced Pluripotent Stem Cells from Nijmegen Breakage Syndrome Patients. Cell Rep 2016; 16:2499-511. [PMID: 27545893 DOI: 10.1016/j.celrep.2016.07.071] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2015] [Revised: 05/29/2016] [Accepted: 07/26/2016] [Indexed: 01/09/2023] Open
Abstract
Nijmegen breakage syndrome (NBS) results from the absence of the NBS1 protein, responsible for detection of DNA double-strand breaks (DSBs). NBS is characterized by microcephaly, growth retardation, immunodeficiency, and cancer predisposition. Here, we show successful reprogramming of NBS fibroblasts into induced pluripotent stem cells (NBS-iPSCs). Our data suggest a strong selection for karyotypically normal fibroblasts to go through the reprogramming process. NBS-iPSCs then acquire numerous chromosomal aberrations and show a delayed response to DSB induction. Furthermore, NBS-iPSCs display slower growth, mitotic inhibition, a reduced apoptotic response to stress, and abnormal cell-cycle-related gene expression. Importantly, NBS neural progenitor cells (NBS-NPCs) show downregulation of neural developmental genes, which seems to be mediated by P53. Our results demonstrate the importance of NBS1 in early human development, shed light on the molecular mechanisms underlying this severe syndrome, and further expand our knowledge of the genomic stress cells experience during the reprogramming process.
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Affiliation(s)
- Tomer Halevy
- The Azrieli Center for Stem Cells and Genetic Research, The Hebrew University, Givat-Ram, Jerusalem 91904, Israel; Department of Genetics, Institute of Life Sciences, The Hebrew University, Givat-Ram, Jerusalem 91904, Israel
| | - Shira Akov
- The Azrieli Center for Stem Cells and Genetic Research, The Hebrew University, Givat-Ram, Jerusalem 91904, Israel; Department of Genetics, Institute of Life Sciences, The Hebrew University, Givat-Ram, Jerusalem 91904, Israel
| | - Martina Bohndorf
- Institute for Stem Cell Research and Regenerative Medicine, Medical Faculty, Heinrich-Heine-University Duesseldorf, Moorenstrasse 5, 40225 Duesseldorf, Germany
| | - Barbara Mlody
- Institute for Stem Cell Research and Regenerative Medicine, Medical Faculty, Heinrich-Heine-University Duesseldorf, Moorenstrasse 5, 40225 Duesseldorf, Germany
| | - James Adjaye
- Institute for Stem Cell Research and Regenerative Medicine, Medical Faculty, Heinrich-Heine-University Duesseldorf, Moorenstrasse 5, 40225 Duesseldorf, Germany
| | - Nissim Benvenisty
- The Azrieli Center for Stem Cells and Genetic Research, The Hebrew University, Givat-Ram, Jerusalem 91904, Israel; Department of Genetics, Institute of Life Sciences, The Hebrew University, Givat-Ram, Jerusalem 91904, Israel.
| | - Michal Goldberg
- Department of Genetics, Institute of Life Sciences, The Hebrew University, Givat-Ram, Jerusalem 91904, Israel.
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Paudyal SC, You Z. Sharpening the ends for repair: mechanisms and regulation of DNA resection. Acta Biochim Biophys Sin (Shanghai) 2016; 48:647-57. [PMID: 27174871 DOI: 10.1093/abbs/gmw043] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2016] [Accepted: 04/12/2016] [Indexed: 12/23/2022] Open
Abstract
DNA end resection is a key process in the cellular response to DNA double-strand break damage that is essential for genome maintenance and cell survival. Resection involves selective processing of 5' ends of broken DNA to generate ssDNA overhangs, which in turn control both DNA repair and checkpoint signaling. DNA resection is the first step in homologous recombination-mediated repair and a prerequisite for the activation of the ataxia telangiectasia mutated and Rad3-related (ATR)-dependent checkpoint that coordinates repair with cell cycle progression and other cellular processes. Resection occurs in a cell cycle-dependent manner and is regulated by multiple factors to ensure an optimal amount of ssDNA required for proper repair and genome stability. Here, we review the latest findings on the molecular mechanisms and regulation of the DNA end resection process and their implications for cancer formation and treatment.
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Affiliation(s)
- Sharad C Paudyal
- Department of Cell Biology and Physiology, Washington University School of Medicine, St Louis, MO 63110, USA
| | - Zhongsheng You
- Department of Cell Biology and Physiology, Washington University School of Medicine, St Louis, MO 63110, USA
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Laffitte MCN, Leprohon P, Hainse M, Légaré D, Masson JY, Ouellette M. Chromosomal Translocations in the Parasite Leishmania by a MRE11/RAD50-Independent Microhomology-Mediated End Joining Mechanism. PLoS Genet 2016; 12:e1006117. [PMID: 27314941 PMCID: PMC4912120 DOI: 10.1371/journal.pgen.1006117] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2015] [Accepted: 05/20/2016] [Indexed: 01/15/2023] Open
Abstract
The parasite Leishmania often relies on gene rearrangements to survive stressful environments. However, safeguarding a minimum level of genome integrity is important for cell survival. We hypothesized that maintenance of genomic integrity in Leishmania would imply a leading role of the MRE11 and RAD50 proteins considering their role in DNA repair, chromosomal organization and protection of chromosomes ends in other organisms. Attempts to generate RAD50 null mutants in a wild-type background failed and we provide evidence that this gene is essential. Remarkably, inactivation of RAD50 was possible in a MRE11 null mutant that we had previously generated, providing good evidence that RAD50 may be dispensable in the absence of MRE11. Inactivation of the MRE11 and RAD50 genes led to a decreased frequency of homologous recombination and analysis of the null mutants by whole genome sequencing revealed several chromosomal translocations. Sequencing of the junction between translocated chromosomes highlighted microhomology sequences at the level of breakpoint regions. Sequencing data also showed a decreased coverage at subtelomeric locations in many chromosomes in the MRE11-/-RAD50-/- parasites. This study demonstrates an MRE11-independent microhomology-mediated end-joining mechanism and a prominent role for MRE11 and RAD50 in the maintenance of genomic integrity. Moreover, we suggest the possible involvement of RAD50 in subtelomeric regions stability. The parasite Leishmania relies on gene rearrangements to survive stressful conditions. However, maintaining a minimum level of genomic integrity is crucial for cell survival. Studies in other organisms have provided evidence that the DNA repair proteins MRE11 and RAD50 are involved in chromosomes organization, protection of chromosomes ends and therefore in the maintenance of genomic integrity. In this manuscript, we present the conditional inactivation of the Leishmania infantum RAD50 gene that was only possible in MRE11 deficient cells and suggest the genetic background is crucial for RAD50 inactivation. We demonstrate the occurrence of chromosomal translocations in the MRE11 and RAD50 deficient cells and described a MRE11-independent microhomology-mediated end-joining mechanism at the level of translocation breakpoints. We also suggest a possible involvement of RAD50 in subtelomeric regions stability. Our results highlight that both MRE11 and RAD50 are important for the maintenance of genomic integrity in Leishmania.
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Affiliation(s)
| | - Philippe Leprohon
- Centre de Recherche en Infectiologie, CRCHU de Québec, Québec City, Québec, Canada
| | - Maripier Hainse
- Genome Stability Laboratory, CRCHU de Québec, Pavillon HDQ Oncology axis, Québec City, Québec, Canada
| | - Danielle Légaré
- Centre de Recherche en Infectiologie, CRCHU de Québec, Québec City, Québec, Canada
| | - Jean-Yves Masson
- Genome Stability Laboratory, CRCHU de Québec, Pavillon HDQ Oncology axis, Québec City, Québec, Canada
- Department of Molecular Biology, Medical Biochemistry and Pathology, Centre de recherche sur le Cancer, Université Laval, Québec City, Québec, Canada
| | - Marc Ouellette
- Centre de Recherche en Infectiologie, CRCHU de Québec, Québec City, Québec, Canada
- * E-mail:
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49
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Kaminsky N, Bihari O, Kanner S, Barzilai A. Connecting Malfunctioning Glial Cells and Brain Degenerative Disorders. GENOMICS, PROTEOMICS & BIOINFORMATICS 2016; 14:155-165. [PMID: 27245308 PMCID: PMC4936608 DOI: 10.1016/j.gpb.2016.04.003] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/17/2016] [Revised: 04/21/2016] [Accepted: 04/22/2016] [Indexed: 12/19/2022]
Abstract
The DNA damage response (DDR) is a complex biological system activated by different types of DNA damage. Mutations in certain components of the DDR machinery can lead to genomic instability disorders that culminate in tissue degeneration, premature aging, and various types of cancers. Intriguingly, malfunctioning DDR plays a role in the etiology of late onset brain degenerative disorders such as Parkinson's, Alzheimer's, and Huntington's diseases. For many years, brain degenerative disorders were thought to result from aberrant neural death. Here we discuss the evidence that supports our novel hypothesis that brain degenerative diseases involve dysfunction of glial cells (astrocytes, microglia, and oligodendrocytes). Impairment in the functionality of glial cells results in pathological neuro-glial interactions that, in turn, generate a "hostile" environment that impairs the functionality of neuronal cells. These events can lead to systematic neural demise on a scale that appears to be proportional to the severity of the neurological deficit.
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Affiliation(s)
- Natalie Kaminsky
- Department of Neurobiology, George S. Wise, Faculty of Life Sciences, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Ofer Bihari
- Department of Neurobiology, George S. Wise, Faculty of Life Sciences, Tel Aviv University, Tel Aviv 6997801, Israel; Sagol School of Neuroscience, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Sivan Kanner
- Department of Neurobiology, George S. Wise, Faculty of Life Sciences, Tel Aviv University, Tel Aviv 6997801, Israel.
| | - Ari Barzilai
- Department of Neurobiology, George S. Wise, Faculty of Life Sciences, Tel Aviv University, Tel Aviv 6997801, Israel; Sagol School of Neuroscience, Tel Aviv University, Tel Aviv 6997801, Israel.
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50
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Liu T, Huang J. DNA End Resection: Facts and Mechanisms. GENOMICS PROTEOMICS & BIOINFORMATICS 2016; 14:126-130. [PMID: 27240470 PMCID: PMC4936662 DOI: 10.1016/j.gpb.2016.05.002] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Revised: 05/04/2016] [Accepted: 05/05/2016] [Indexed: 01/05/2023]
Abstract
DNA double-strand breaks (DSBs), which arise following exposure to a number of endogenous and exogenous agents, can be repaired by either the homologous recombination (HR) or non-homologous end-joining (NHEJ) pathways in eukaryotic cells. A vital step in HR repair is DNA end resection, which generates a long 3′ single-stranded DNA (ssDNA) tail that can invade the homologous DNA strand. The generation of 3′ ssDNA is not only essential for HR repair, but also promotes activation of the ataxia telangiectasia and Rad3-related protein (ATR). Multiple factors, including the MRN/X complex, C-terminal-binding protein interacting protein (CtIP)/Sae2, exonuclease 1 (EXO1), Bloom syndrome protein (BLM)/Sgs1, DNA2 nuclease/helicase, and several chromatin remodelers, cooperate to complete the process of end resection. Here we review the basic machinery involved in DNA end resection in eukaryotic cells.
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Affiliation(s)
- Ting Liu
- Department of Cell Biology and Program in Molecular Cell Biology, Zhejiang University School of Medicine, Hangzhou 310058, China.
| | - Jun Huang
- Life Sciences Institute and Innovation Center for Cell Signaling Network, Zhejiang University, Hangzhou 310058, China.
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