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Cui X, Hou J, Wang S, Yu J, Cheng S, Yu L, Song FJ, Luo H. Werner helicase mediates the senescence and cell cycle of leukemia cells by regulating DNA repair pathways. Int J Biol Macromol 2024; 255:128305. [PMID: 37992942 DOI: 10.1016/j.ijbiomac.2023.128305] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Revised: 10/23/2023] [Accepted: 11/19/2023] [Indexed: 11/24/2023]
Abstract
Leukemia is a type of malignant hematological disease that is generally resistant to chemotherapy and has poor therapeutic outcomes. Werner (WRN) DNA helicase, an important member of the RecQ family of helicases, plays an important role in DNA repair and telomere stability maintenance. WRN gene dysfunction leads to premature aging and predisposes humans to various types of cancers. However, the biological function of WRN in cancer remains unknown. In this study, the expression of this RecQ family helicase was investigated in different types of leukemia cells, and the leukemia cell line K562 with high WRN expression was selected to construct a WRN knockdown cell line. The results showed that WRN knockdown inhibited leukemia occurrence and development by regulating the proliferation, cell cycle, differentiation, and aging of cells and other biological processes. The results of transcriptome sequencing revealed that WRN promoted the sensitivity of leukemia cells to the DNA damage inducer Etoposide by regulating cell cycle-related proteins, such as CDC2, cyclin B1, p16, and p21, as well as key proteins in DNA damage repair pathways, such as p53, RAD50, RAD51, and MER11. Our findings show that WRN helicase is a promising potential target for leukemia treatment, providing new ideas for the development of targeted drugs against leukemia.
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Affiliation(s)
- Xudong Cui
- State Key Laboratory of Functions and Applications of Medicinal Plants, Guizhou Medical University, Guiyang 550014, PR China; Natural Products Research Center of Guizhou Province, Guiyang 550014, PR China; Department of Infectious Disease, The Fourth Hospital of Harbin Medical University, Harbin 150001, PR China
| | - Jing Hou
- Natural Products Research Center of Guizhou Province, Guiyang 550014, PR China; College of Life Sciences, South-Central University for Nationalities, Wuhan 430074, PR China
| | - Shimei Wang
- State Key Laboratory of Functions and Applications of Medicinal Plants, Guizhou Medical University, Guiyang 550014, PR China; Natural Products Research Center of Guizhou Province, Guiyang 550014, PR China; Department of Infectious Disease, The Fourth Hospital of Harbin Medical University, Harbin 150001, PR China
| | - Jia Yu
- State Key Laboratory of Functions and Applications of Medicinal Plants, Guizhou Medical University, Guiyang 550014, PR China; Natural Products Research Center of Guizhou Province, Guiyang 550014, PR China
| | - Sha Cheng
- State Key Laboratory of Functions and Applications of Medicinal Plants, Guizhou Medical University, Guiyang 550014, PR China; Natural Products Research Center of Guizhou Province, Guiyang 550014, PR China
| | - Lei Yu
- State Key Laboratory of Functions and Applications of Medicinal Plants, Guizhou Medical University, Guiyang 550014, PR China; Department of Infectious Disease, The Fourth Hospital of Harbin Medical University, Harbin 150001, PR China.
| | - Fa-Jun Song
- College of Life Sciences, South-Central University for Nationalities, Wuhan 430074, PR China.
| | - Heng Luo
- State Key Laboratory of Functions and Applications of Medicinal Plants, Guizhou Medical University, Guiyang 550014, PR China; Natural Products Research Center of Guizhou Province, Guiyang 550014, PR China.
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Koschitzki K, Ivanova I, Berneburg M. [Progeroid syndromes : Aging, skin aging, and mechanisms of progeroid syndromes]. DERMATOLOGIE (HEIDELBERG, GERMANY) 2023; 74:696-706. [PMID: 37650893 PMCID: PMC10480280 DOI: 10.1007/s00105-023-05212-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 07/21/2023] [Indexed: 09/01/2023]
Abstract
Progeroid syndromes (PSs) are characterized by the premature onset of age-related pathologies. PSs display a wide range of heterogeneous pathological symptoms that also manifest during natural aging, including vision and hearing loss, atrophy, hair loss, progressive neurodegeneration, and cardiovascular defects. Recent advances in molecular pathology have led to a better understanding of the underlying mechanisms of these diseases. The genetic mutations underlying PSs are functionally linked to genome maintenance and repair, supporting the causative role of DNA damage accumulation in aging. While some of those genes encode proteins with a direct involvement in a DNA repair machinery, such as nucleotide excision repair (NER), others destabilize the genome by compromising the stability of the nuclear envelope, when lamin A is dysfunctional in Hutchinson-Gilford progeria syndrome (HGPS) or regulate the DNA damage response (DDR) such as the ataxia telangiectasia-mutated (ATM) gene. Understanding the molecular pathology of progeroid diseases is crucial in developing potential treatments to manage and prevent the onset of symptoms. This knowledge provides insight into the underlying mechanisms of premature aging and could lead to improved quality of life for individuals affected by progeroid diseases.
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Affiliation(s)
- Kevin Koschitzki
- Poliklinik und Klinik für Dermatologie, Universitätsklinikum Regensburg, Regensburg, Deutschland.
| | - Irina Ivanova
- Poliklinik und Klinik für Dermatologie, Universitätsklinikum Regensburg, Regensburg, Deutschland
| | - Mark Berneburg
- Poliklinik und Klinik für Dermatologie, Universitätsklinikum Regensburg, Regensburg, Deutschland
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Sun N, Shen J, Shi Y, Liu B, Gao S, Chen Y, Sun J. TRIM58 functions as a tumor suppressor in colorectal cancer by promoting RECQL4 ubiquitination to inhibit the AKT signaling pathway. World J Surg Oncol 2023; 21:231. [PMID: 37516854 PMCID: PMC10385910 DOI: 10.1186/s12957-023-03124-4] [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: 04/12/2023] [Accepted: 07/23/2023] [Indexed: 07/31/2023] Open
Abstract
BACKGROUND This study aimed to investigate the underlying molecular mechanisms of TRIM58 in the development of colorectal cancer (CRC). CRC is one of the most common cancers of the digestive tract worldwide. The ubiquitin-proteasome system regulates many oncogenic or tumor-suppressive proteins. TRIM58, an E3 ubiquitin ligase and a member of the tripartite motif protein family, is a potential prognostic marker that indicates poor prognosis in cancer. Currently, the precise molecular mechanisms for the TRIM58-mediated CRC progression remain unclear. METHODS To examine the effects of TRIM58 on cell viability, cell cycle progression, and apoptosis in CRC, Cell Counting Kit-8 and flow cytometry assays were employed. The AKT inhibitor LY294002 was used to examine the effects of AKT signaling on TRIM58-mediated cell viability, cell cycle progression, and apoptosis in CRC. Additionally, Co-IP and ubiquitination assays were used to examine the correlation between TRIM58 and RECQL4. RESULTS TRIM58 overexpression inhibited CRC cell viability and promoted cell cycle arrest and apoptosis, in which the TRIM58 knockdown demonstrated inversed effects via the AKT signaling pathway. TRIM58 inhibited RECQL4 protein levels through its ubiquitin ligase activity, and RECQL4 overexpression inhibited TRIM58 overexpression-mediated CRC cell viability, cell cycle progression, and apoptosis. The downregulation of TRIM58 and upregulation of RECOL4 were observed in human CRC tissue, and TRIM58 demonstrated antitumor effects in CRC-induced tumor growth in a mouse model. CONCLUSIONS TRIM58 acts as a tumor suppressor in CRC through the promotion of RECQL4 ubiquitination and inhibition of the AKT signaling pathway and may be investigated for the successful treatment of CRC.
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Affiliation(s)
- Naizhi Sun
- Department of General Surgery, North Hospital of Yancheng Third People's Hospital, The Yancheng School of Clinical Medicine of Nanjing Medical, Theater Road No. 75, Tinghu District, Yancheng, 224000, Jiangsu Province, China
| | - Jiacheng Shen
- Department of General Surgery, North Hospital of Yancheng Third People's Hospital, The Yancheng School of Clinical Medicine of Nanjing Medical, Theater Road No. 75, Tinghu District, Yancheng, 224000, Jiangsu Province, China
| | - Yuhua Shi
- Department of General Surgery, North Hospital of Yancheng Third People's Hospital, The Yancheng School of Clinical Medicine of Nanjing Medical, Theater Road No. 75, Tinghu District, Yancheng, 224000, Jiangsu Province, China
| | - Biao Liu
- Department of General Surgery, North Hospital of Yancheng Third People's Hospital, The Yancheng School of Clinical Medicine of Nanjing Medical, Theater Road No. 75, Tinghu District, Yancheng, 224000, Jiangsu Province, China
| | - Shengguo Gao
- Department of General Surgery, North Hospital of Yancheng Third People's Hospital, The Yancheng School of Clinical Medicine of Nanjing Medical, Theater Road No. 75, Tinghu District, Yancheng, 224000, Jiangsu Province, China
| | - Yichuan Chen
- Department of General Surgery, North Hospital of Yancheng Third People's Hospital, The Yancheng School of Clinical Medicine of Nanjing Medical, Theater Road No. 75, Tinghu District, Yancheng, 224000, Jiangsu Province, China
| | - Jinwei Sun
- Department of General Surgery, North Hospital of Yancheng Third People's Hospital, The Yancheng School of Clinical Medicine of Nanjing Medical, Theater Road No. 75, Tinghu District, Yancheng, 224000, Jiangsu Province, China.
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Joudeh LA, DiCintio AJ, Ries MR, Gasperson AS, Griffin KE, Robbins VP, Bonner M, Nolan S, Black E, Waldman AS. Corruption of DNA end-joining in mammalian chromosomes by progerin expression. DNA Repair (Amst) 2023; 126:103491. [PMID: 37018982 PMCID: PMC10133198 DOI: 10.1016/j.dnarep.2023.103491] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Revised: 03/23/2023] [Accepted: 03/29/2023] [Indexed: 04/03/2023]
Abstract
Hutchinson-Gilford Progeria Syndrome (HGPS) is a rare genetic condition characterized by features of accelerated aging and a life expectancy of about 14 years. HGPS is commonly caused by a point mutation in the LMNA gene which codes for lamin A, an essential component of the nuclear lamina. The HGPS mutation alters splicing of the LMNA transcript, leading to a truncated, farnesylated form of lamin A termed "progerin." Progerin is also produced in small amounts in healthy individuals by alternative splicing of RNA and has been implicated in normal aging. HGPS is associated with an accumulation of genomic DNA double-strand breaks (DSBs), suggesting alteration of DNA repair. DSB repair normally occurs by either homologous recombination (HR), an accurate, templated form of repair, or by nonhomologous end-joining (NHEJ), a non-templated rejoining of DNA ends that can be error-prone; however a good portion of NHEJ events occurs precisely with no alteration to joined sequences. Previously, we reported that over-expression of progerin correlated with increased NHEJ relative to HR. We now report on progerin's impact on the nature of DNA end-joining. We used a model system involving a DNA end-joining reporter substrate integrated into the genome of cultured thymidine kinase-deficient mouse fibroblasts. Some cells were engineered to express progerin. Two closely spaced DSBs were induced in the integrated substrate through expression of endonuclease I-SceI, and DSB repair events were recovered through selection for thymidine kinase function. DNA sequencing revealed that progerin expression correlated with a significant shift away from precise end-joining between the two I-SceI sites and toward imprecise end-joining. Additional experiments revealed that progerin did not reduce HR fidelity. Our work suggests that progerin suppresses interactions between complementary sequences at DNA termini, thereby shifting DSB repair toward low-fidelity DNA end-joining and perhaps contributing to accelerated and normal aging through compromised genome stability.
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Affiliation(s)
- Liza A Joudeh
- Department of Biological Sciences, University of South Carolina, Columbia, SC 29208, USA
| | - Alannah J DiCintio
- Department of Biological Sciences, University of South Carolina, Columbia, SC 29208, USA
| | - Madeline R Ries
- Department of Biological Sciences, University of South Carolina, Columbia, SC 29208, USA
| | - Andrew S Gasperson
- Department of Biological Sciences, University of South Carolina, Columbia, SC 29208, USA
| | - Kennedy E Griffin
- Department of Biological Sciences, University of South Carolina, Columbia, SC 29208, USA
| | - Victoria P Robbins
- Department of Biological Sciences, University of South Carolina, Columbia, SC 29208, USA
| | - Makenzie Bonner
- Department of Biological Sciences, University of South Carolina, Columbia, SC 29208, USA
| | - Sarah Nolan
- Department of Biological Sciences, University of South Carolina, Columbia, SC 29208, USA
| | - Emma Black
- Department of Biological Sciences, University of South Carolina, Columbia, SC 29208, USA
| | - Alan S Waldman
- Department of Biological Sciences, University of South Carolina, Columbia, SC 29208, USA.
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Vijay Kumar MJ, Morales R, Tsvetkov AS. G-quadruplexes and associated proteins in aging and Alzheimer's disease. FRONTIERS IN AGING 2023; 4:1164057. [PMID: 37323535 PMCID: PMC10267416 DOI: 10.3389/fragi.2023.1164057] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2023] [Accepted: 05/17/2023] [Indexed: 06/17/2023]
Abstract
Aging is a prominent risk factor for many neurodegenerative disorders, such as Alzheimer's disease (AD). Alzheimer's disease is characterized by progressive cognitive decline, memory loss, and neuropsychiatric and behavioral symptoms, accounting for most of the reported dementia cases. This disease is now becoming a major challenge and burden on modern society, especially with the aging population. Over the last few decades, a significant understanding of the pathophysiology of AD has been gained by studying amyloid deposition, hyperphosphorylated tau, synaptic dysfunction, oxidative stress, calcium dysregulation, and neuroinflammation. This review focuses on the role of non-canonical secondary structures of DNA/RNA G-quadruplexes (G4s, G4-DNA, and G4-RNA), G4-binding proteins (G4BPs), and helicases, and their roles in aging and AD. Being critically important for cellular function, G4s are involved in the regulation of DNA and RNA processes, such as replication, transcription, translation, RNA localization, and degradation. Recent studies have also highlighted G4-DNA's roles in inducing DNA double-strand breaks that cause genomic instability and G4-RNA's participation in regulating stress granule formation. This review emphasizes the significance of G4s in aging processes and how their homeostatic imbalance may contribute to the pathophysiology of AD.
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Affiliation(s)
- M. J. Vijay Kumar
- The Department of Neurology, The University of Texas McGovern Medical School at Houston, Houston, TX, United States
| | - Rodrigo Morales
- The Department of Neurology, The University of Texas McGovern Medical School at Houston, Houston, TX, United States
- Centro Integrativo de Biologia y Quimica Aplicada (CIBQA), Universidad Bernardo O’Higgins, Santiago, Chile
| | - Andrey S. Tsvetkov
- The Department of Neurology, The University of Texas McGovern Medical School at Houston, Houston, TX, United States
- The University of Texas Graduate School of Biomedical Sciences, Houston, TX, United States
- UTHealth Consortium on Aging, The University of Texas McGovern Medical School, Houston, TX, United States
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Kumar A, Rajaram H. Insights into the presence of multiple RecQ helicases in the ancient cyanobacterium, Nostoc sp. strain PCC7120: bioinformatics and expression analysis approach. Mol Genet Genomics 2023; 298:37-47. [PMID: 36264383 DOI: 10.1007/s00438-022-01963-6] [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: 05/09/2022] [Accepted: 10/09/2022] [Indexed: 01/11/2023]
Abstract
Owing to their crucial role in genome maintenance, RecQ helicases are ubiquitous and present across organisms. Though the multiplicity of RecQ helicases is well known in higher organisms, it is rare among bacteria. The ancient cyanobacterium Nostoc sp. strain PCC7120 was found to have three annotated RecQ helicases. This study aims at understanding its structural differences and evolution through bioinformatics approach and functionality through expression analysis studies. Nostoc RecQ helicases were found to be transcriptionally regulated by LexA and DNA damage inducing stresses. Bioinformatic analysis revealed that all three RecQ helicases of Nostoc possess helicases_C and Zn+2-binding domains. Two of the helicases (AnRecQ and AnRecQ2) lacked the complete RQC and HRDC domains, and AnRecQ2 had an additional Phosphoribosyl transferase domain (Pribosyltran), also seen in RecQ-like helicase (RqlH) protein of Mycobacterium smegmatis. AnRecQ1, which was similar to most bacterial RecQ helicases, differed in having a long C-terminal tail. STRING analysis revealed that the proteins also differed in their predicted protein interactome. Phylogenetic analysis suggested that the multiple recQ genes may have been acquired through duplication and acquisition of additional domains from the smallest of the RecQ helicases (AnRecQ) to cater multiple functions required to deal with the harsh environmental conditions. In course of evolution, however, the multiplicity was lost with the modern-day bacteria and lower eukaryotes which retained fewer RecQ helicases, while further duplication of the acquired RECQ occurred in higher animals and plants to deal with cellular complexity.
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Affiliation(s)
- Arvind Kumar
- Cyanobacterial Stress Biology and Biotechnology Section, Molecular Biology Division, Bhabha Atomic Research Centre, Mumbai, Trombay, 400085, India
| | - Hema Rajaram
- Cyanobacterial Stress Biology and Biotechnology Section, Molecular Biology Division, Bhabha Atomic Research Centre, Mumbai, Trombay, 400085, India. .,Homi Bhabha National Institute, Anushakti Nagar, Mumbai, 400094, India.
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Olukanni OD, Abiola T, Olukanni AT, Ojo AV. Chemical Composition, In Silico and In Vitro Antimutagenic Activities of Ethanolic and Aqueous Extracts of Tigernut ( Cyperus esculentus). Prev Nutr Food Sci 2022; 27:198-211. [PMID: 35919571 PMCID: PMC9309076 DOI: 10.3746/pnf.2022.27.2.198] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Revised: 05/03/2022] [Accepted: 05/20/2022] [Indexed: 12/04/2022] Open
Abstract
Tigernut, also known as Cyperus esculentus, is said to be high in nutritional and medicinal value. The purpose of this study was to determine the C. esculentus’s antimutagenic activity. The ethanolic and aqueous extracts of the nut were analyzed for chemical constituents, antioxidants, ultraviolet-visible, and gas chromatography-mass spectrometry using standard procedures. The extracts contained a total of 17 major compounds that were docked against human RecQ-like protein 5 (RECQL5) helicase protein. The antimutagenic property of the ethanolic extract in vitro was assessed using the Allium cepa chromosome assay. Onion bulbs were pre-treated with 200 mg/kg of ethanolic extract of C. esculentus for 24 h and then, grown in NaN3 (250 μg/L) for 24 h; onion bulbs were also first exposed to NaN3 (250 μg/L) for 24 h before treatment with 100 mg/kg and 200 mg/kg of the ethanolic extract respectively. Standard methods were used to determine the mitotic index and chromosomal aberrations. Results revealed that C. esculentus ethanolic extract contained flavonoids (22.47 mg/g), tannins (0.08 mg/g), alkaloids (19.71 mg/g), glycosides, phenol, and tannin and showed high scavenging activity against 2,2-diphenyl-1-picrylhydrazyland H2O2. Docking with RECQL5 showed good binding energies (∆G>−7) of five compounds in C. esculentus ethanolic extract. The A. cepa assay results revealed a significant (P<0.05) reduction in chromosomal aberrations and a higher mitotic index in groups treated with the C. esculentus ethanolic extract. The antimutagenic activity of C. esculentus ethanolic extract was attributed to its high levels of phytosterols and phenolic compounds.
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Affiliation(s)
- Olumide David Olukanni
- Department of Biochemistry, Faculty of Basic Medical Sciences, Redeemer’s University, Ede, Osun State 232101, Nigeria
| | - Temitope Abiola
- Department of Biochemistry, Faculty of Basic Medical Sciences, Redeemer’s University, Ede, Osun State 232101, Nigeria
| | - Adedayo Titilayo Olukanni
- Department of Biochemistry, Faculty of Basic Medical Sciences, Redeemer’s University, Ede, Osun State 232101, Nigeria
| | - Abosede Victoria Ojo
- Department of Chemical Sciences, Biochemistry Unit, College of Natural and Applied Sciences, Oduduwa University, Ile-Ife, Osun State 220101, Nigeria
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Dello Stritto MR, Vojtassakova N, Velkova M, Hamminger P, Ulm P, Jantsch V. The topoisomerase 3 zinc finger domain cooperates with the RMI1 scaffold to promote stable association of the BTR complex to recombination intermediates in the Caenorhabditis elegans germline. Nucleic Acids Res 2022; 50:5652-5671. [PMID: 35639927 PMCID: PMC9178014 DOI: 10.1093/nar/gkac408] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 05/01/2022] [Accepted: 05/09/2022] [Indexed: 11/14/2022] Open
Abstract
Homologous recombination is the predominant DNA repair pathway used in the gonad. Of the excess DNA double-strand breaks formed in meiosis, only a subset matures into crossovers, with the remainder repaired as non-crossovers. The conserved BTR complex (comprising Bloom helicase, topoisomerase 3 and RMI1/2 scaffold proteins) acts at multiple steps during recombination to dismantle joint DNA molecules, thereby mediating the non-crossover outcome and chromosome integrity. Furthermore, the complex displays a role at the crossover site that is less well understood. Besides catalytic and TOPRIM domains, topoisomerase 3 enzymes contain a variable number of carboxy terminal zinc finger (ZnF) domains. Here, we studied the Caenorhabditis elegans mutant, in which the single ZnF domain is deleted. In contrast to the gene disruption allele, the top-3-ZnF mutant is viable, with no replication defects; the allele appears to be a hypomorph. The TOP-3-ZnF protein is recruited into foci but the mutant has increased numbers of crossovers along its chromosomes, with minor defects in repressing heterologous recombination, and a marked delay in the maturation/processing of recombination intermediates after loading of the RAD-51 recombinase. The ZnF domain cooperates with the RMI1 homolog RMH-2 to stabilize association of the BTR complex with recombination intermediates and to prevent recombination between heterologous DNA sequences.
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Affiliation(s)
| | - Nina Vojtassakova
- Department of Chromosome Biology, Max Perutz Laboratories, University of Vienna, Vienna Biocenter, Austria
| | - Maria Velkova
- Department of Chromosome Biology, Max Perutz Laboratories, University of Vienna, Vienna Biocenter, Austria
| | - Patricia Hamminger
- Department of Chromosome Biology, Max Perutz Laboratories, University of Vienna, Vienna Biocenter, Austria
| | - Patricia Ulm
- Department of Chromosome Biology, Max Perutz Laboratories, University of Vienna, Vienna Biocenter, Austria
| | - Verena Jantsch
- Department of Chromosome Biology, Max Perutz Laboratories, University of Vienna, Vienna Biocenter, Austria
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Growth Inhibition of Two Prenylated Chalcones on Prostate Cancer Cells through the Regulation of the Biological Activity and Protein Translation of Bloom Helicase. Catalysts 2022. [DOI: 10.3390/catal12060582] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Bloom (BLM) helicase is an important member of the RecQ family of DNA helicases that plays a vital role in the maintenance of genomic stability. The defect of BLM helicase leads to a human genetic disorder called Bloom syndrome, characterized by genomic instability, specific phenotypic features, and a predisposition to many types of cancer. The predisposition to cancer caused by BLM helicase is due to defects in important DNA metabolic pathways such as replication, recombination, and repair. Therefore, the aim of this work was to investigate the effects of two prenylated chalcones, WZH-10 and WZH-43, on the expression of BLM helicase in prostate cancer cells, as well as the biological activity of the purified BLM helicase from cancer cells. This might lead to a better understanding of the role of BLM helicase in the aforementioned DNA metabolic pathways that directly influence chromosomal integrity leading to cancer. The results indicated that the two prenylated chalcones inhibited the growth of prostate cancer cells PC3 by inducing apoptosis and arresting the cell cycle. However, they only inhibited the protein expression of BLM helicase without regulating its transcriptional expression. In addition, they did not significantly regulate the expression of the homologous family members WRN and RECQL1, although the DNA unwinding and ATPase activity of BLM helicase were inhibited by the two prenylated chalcones. Finally, a negligible effect was found on the DNA-binding activity of this enzyme. These results demonstrated that prenylated chalcones can be an effective intervention on the expression and function of the BLM helicase protein in cancer cells to inhibit their growth. Therefore, they might provide a novel strategy for developing new anti-cancer drugs targeting the genomic stability and DNA helicase.
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RQC helical hairpin in Bloom's syndrome helicase regulates DNA unwinding by dynamically intercepting nascent nucleotides. iScience 2022; 25:103606. [PMID: 35005551 PMCID: PMC8718986 DOI: 10.1016/j.isci.2021.103606] [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: 07/07/2021] [Revised: 11/03/2021] [Accepted: 12/08/2021] [Indexed: 11/24/2022] Open
Abstract
The RecQ family of helicases are important for maintenance of genomic integrity. Although functions of constructive subdomains of this family of helicases have been extensively studied, the helical hairpin (HH) in the RecQ-C-terminal domain (RQC) has been underappreciated and remains poorly understood. Here by using single-molecule fluorescence resonance energy transfer, we found that HH in the human BLM transiently intercepts different numbers of nucleotides when it is unwinding a double-stranded DNA. Single-site mutations in HH that disrupt hydrogen bonds and/or salt bridges between DNA and HH change the DNA binding conformations and the unwinding features significantly. Our results, together with recent clinical tests that correlate single-site mutations in HH of human BLM with the phenotype of cancer-predisposing syndrome or Bloom's syndrome, implicate pivotal roles of HH in BLM's DNA unwinding activity. Similar mechanisms might also apply to other RecQ family helicases, calling for more attention to the RQC helical hairpin.
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11
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Velkova M, Silva N, Dello Stritto MR, Schleiffer A, Barraud P, Hartl M, Jantsch V. Caenorhabditis elegans RMI2 functional homolog-2 (RMIF-2) and RMI1 (RMH-1) have both overlapping and distinct meiotic functions within the BTR complex. PLoS Genet 2021; 17:e1009663. [PMID: 34252074 PMCID: PMC8318279 DOI: 10.1371/journal.pgen.1009663] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Revised: 07/28/2021] [Accepted: 06/11/2021] [Indexed: 12/23/2022] Open
Abstract
Homologous recombination is a high-fidelity repair pathway for DNA double-strand breaks employed during both mitotic and meiotic cell divisions. Such repair can lead to genetic exchange, originating from crossover (CO) generation. In mitosis, COs are suppressed to prevent sister chromatid exchange. Here, the BTR complex, consisting of the Bloom helicase (HIM-6 in worms), topoisomerase 3 (TOP-3), and the RMI1 (RMH-1 and RMH-2) and RMI2 scaffolding proteins, is essential for dismantling joint DNA molecules to form non-crossovers (NCOs) via decatenation. In contrast, in meiosis COs are essential for accurate chromosome segregation and the BTR complex plays distinct roles in CO and NCO generation at different steps in meiotic recombination. RMI2 stabilizes the RMI1 scaffolding protein, and lack of RMI2 in mitosis leads to elevated sister chromatid exchange, as observed upon RMI1 knockdown. However, much less is known about the involvement of RMI2 in meiotic recombination. So far, RMI2 homologs have been found in vertebrates and plants, but not in lower organisms such as Drosophila, yeast, or worms. We report the identification of the Caenorhabditis elegans functional homolog of RMI2, which we named RMIF-2. The protein shows a dynamic localization pattern to recombination foci during meiotic prophase I and concentration into recombination foci is mutually dependent on other BTR complex proteins. Comparative analysis of the rmif-2 and rmh-1 phenotypes revealed numerous commonalities, including in regulating CO formation and directing COs toward chromosome arms. Surprisingly, the prevalence of heterologous recombination was several fold lower in the rmif-2 mutant, suggesting that RMIF-2 may be dispensable or less strictly required for some BTR complex-mediated activities during meiosis. Bloom syndrome is caused by mutations in proteins of the BTR complex (consisting of the Bloom helicase, topoisomerase 3, and the RMI1 and RMI2 scaffolding proteins) and the clinical characteristics are growth deficiency, short stature, skin photosensitivity, and increased cancer predisposition. At the cellular level, characteristic features are the presence of increased sister chromatid exchange on chromosomes; unresolved DNA recombination intermediates that eventually cause genome instability; and erroneous DNA repair by heterologous recombination (recombination between non-identical sequences, extremely rare in wild type animals), which can trigger translocations and chromosomal rearrangements. Identification of the Caenorhabditis elegans ortholog of RMI2 (called RMIF-2) allowed us to compare heterologous recombination in the germline of mutants of various BTR complex proteins. The heterologous recombination rate was several fold lower in rmif-2 mutants than in mutants of rmh-1 and him-6 (worm homologs of RMI1 and the Bloom helicase, respectively). Nevertheless, many phenotypic features point at RMIF-2 working together with RMH-1. If these germline functions of RMI2/RMIF-2 are conserved in humans, this might mean that individuals with RMI2 mutations have a lower risk of translocations and genome rearrangements than those with mutations in the other BTR complex genes.
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Affiliation(s)
- Maria Velkova
- Department of Chromosome Biology, Max Perutz Labs, Vienna BioCenter, Vienna, Austria
| | - Nicola Silva
- Department of Chromosome Biology, Max Perutz Labs, Vienna BioCenter, Vienna, Austria
| | | | - Alexander Schleiffer
- Research Institute of Molecular Pathology, Campus Vienna BioCenter, Vienna 1, Vienna, Austria
- Institute of Molecular Biotechnology, Campus Vienna BioCenter, Vienna, Austria
| | - Pierre Barraud
- Expression Génétique Microbienne, UMR 8261, Centre national de la recherche scientifique, Université de Paris, Institut de Biologie Physico-Chimique, Paris, France
| | - Markus Hartl
- Mass Spectrometry Facility, Max Perutz Labs, Vienna BioCenter, Vienna, Austria
| | - Verena Jantsch
- Department of Chromosome Biology, Max Perutz Labs, Vienna BioCenter, Vienna, Austria
- * E-mail:
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12
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Zhu XH, Sun BF, Luo M, Yu J, Zhang YD, Xu HQ, Luo H. Bloom helicase explicitly unwinds 3'-tailed G4DNA structure in prostate cancer cells. Int J Biol Macromol 2021; 180:578-589. [PMID: 33727188 DOI: 10.1016/j.ijbiomac.2021.03.060] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 01/22/2021] [Accepted: 03/11/2021] [Indexed: 10/21/2022]
Abstract
G-quadruplex DNA (G4DNA) structure, which widely exists in the chromosomal telomeric regions and oncogenic promoter regions, plays a pivotal role in extending telomeric DNA with the help of telomerase in human cells. Bloom (BLM) helicase, a crucial member of the family of genome surveillance proteins, plays an essential role in DNA metabolic and repair pathways, including DNA replication, repair, transcription, recombination during chromosome segregation, and assuring telomere stability. The unwinding of G4DNA requires the participation of DNA helicase, which is crucial for maintaining chromosomal stability in cancer cells. Using fluorescence polarization and the electrophoretic mobility shift assay (EMSA), this study aimed to investigate the DNA-binding and unwinding properties of BLM helicase, cloned and purified from prostate cancer cells, toward G4DNA. The results revealed that BLM helicase derived from prostate cancer cells could bind and unwind G4DNA. The molecular affinity of bond between G4DNA and the helicase was dependent on the single-stranded DNA (ssDNA) terminals in G4DNA; the helicase was effectively bound to the G4DNA when the helicase monomer sufficiently covered approximately 10 nucleotides at the 3' or 5' ssDNA tail of G4DNA. For the unwinding of G4DNA, there was an apparent requirement of a 3' ssDNA tail and ATP; a G4DNA with only a 3' ssDNA tail was identified to be the most suitable substrate to be unwound by BLM helicase and required 3' ssDNA tails of at least 10 nt in length for efficient unwinding. Besides, BLM helicase was loosely bound and partly unwound the blunt-ended G4DNA. Although further mechanistic studies are warranted, the experimental results presented in this study are beneficial to further our understanding of the functional implication of BLM helicase in prostate cancer cells.
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Affiliation(s)
- Xu-Hui Zhu
- State Key Laboratory of Functions And Applications of Medicinal Plants, Guizhou Medical University, Guiyang 550014, PR China; Beijing ChaoYang Hospital, Capital Medical University, Beijing 100016, PR China
| | - Bao-Fei Sun
- State Key Laboratory of Functions And Applications of Medicinal Plants, Guizhou Medical University, Guiyang 550014, PR China
| | - Mei Luo
- State Key Laboratory of Functions And Applications of Medicinal Plants, Guizhou Medical University, Guiyang 550014, PR China; The Key Laboratory of Chemistry for Natural Products of Guizhou Province and Chinese Academy of Science, Guiyang 550014, PR China
| | - Jia Yu
- State Key Laboratory of Functions And Applications of Medicinal Plants, Guizhou Medical University, Guiyang 550014, PR China; The Key Laboratory of Chemistry for Natural Products of Guizhou Province and Chinese Academy of Science, Guiyang 550014, PR China
| | | | - Hou-Qiang Xu
- Key Laboratory of Animal Genetics, Breeding and Reproduction in the Plateau Mountainous Region, Ministry of Education, College of Animal Science, Guizhou University, Guiyang 550025, PR China.
| | - Heng Luo
- State Key Laboratory of Functions And Applications of Medicinal Plants, Guizhou Medical University, Guiyang 550014, PR China; The Key Laboratory of Chemistry for Natural Products of Guizhou Province and Chinese Academy of Science, Guiyang 550014, PR China; Key Laboratory of Animal Genetics, Breeding and Reproduction in the Plateau Mountainous Region, Ministry of Education, College of Animal Science, Guizhou University, Guiyang 550025, PR China.
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13
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Kaur E, Agrawal R, Sengupta S. Functions of BLM Helicase in Cells: Is It Acting Like a Double-Edged Sword? Front Genet 2021; 12:634789. [PMID: 33777104 PMCID: PMC7994599 DOI: 10.3389/fgene.2021.634789] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2020] [Accepted: 02/11/2021] [Indexed: 12/14/2022] Open
Abstract
DNA damage repair response is an important biological process involved in maintaining the fidelity of the genome in eukaryotes and prokaryotes. Several proteins that play a key role in this process have been identified. Alterations in these key proteins have been linked to different diseases including cancer. BLM is a 3′−5′ ATP-dependent RecQ DNA helicase that is one of the most essential genome stabilizers involved in the regulation of DNA replication, recombination, and both homologous and non-homologous pathways of double-strand break repair. BLM structure and functions are known to be conserved across many species like yeast, Drosophila, mouse, and human. Genetic mutations in the BLM gene cause a rare, autosomal recessive disorder, Bloom syndrome (BS). BS is a monogenic disease characterized by genomic instability, premature aging, predisposition to cancer, immunodeficiency, and pulmonary diseases. Hence, these characteristics point toward BLM being a tumor suppressor. However, in addition to mutations, BLM gene undergoes various types of alterations including increase in the copy number, transcript, and protein levels in multiple types of cancers. These results, along with the fact that the lack of wild-type BLM in these cancers has been associated with increased sensitivity to chemotherapeutic drugs, indicate that BLM also has a pro-oncogenic function. While a plethora of studies have reported the effect of BLM gene mutations in various model organisms, there is a dearth in the studies undertaken to investigate the effect of its oncogenic alterations. We propose to rationalize and integrate the dual functions of BLM both as a tumor suppressor and maybe as a proto-oncogene, and enlist the plausible mechanisms of its deregulation in cancers.
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Affiliation(s)
- Ekjot Kaur
- Signal Transduction Laboratory-2, National Institute of Immunology, New Delhi, India
| | - Ritu Agrawal
- Signal Transduction Laboratory-2, National Institute of Immunology, New Delhi, India
| | - Sagar Sengupta
- Signal Transduction Laboratory-2, National Institute of Immunology, New Delhi, India
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14
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Newman JA, Gavard AE, Lieb S, Ravichandran MC, Hauer K, Werni P, Geist L, Böttcher J, Engen JR, Rumpel K, Samwer M, Petronczki M, Gileadi O. Structure of the helicase core of Werner helicase, a key target in microsatellite instability cancers. Life Sci Alliance 2021; 4:e202000795. [PMID: 33199508 PMCID: PMC7671478 DOI: 10.26508/lsa.202000795] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Revised: 10/28/2020] [Accepted: 10/28/2020] [Indexed: 11/24/2022] Open
Abstract
Loss of WRN, a DNA repair helicase, was identified as a strong vulnerability of microsatellite instable (MSI) cancers, making WRN a promising drug target. We show that ATP binding and hydrolysis are required for genome integrity and viability of MSI cancer cells. We report a 2.2-Å crystal structure of the WRN helicase core (517-1,093), comprising the two helicase subdomains and winged helix domain but not the HRDC domain or nuclease domains. The structure highlights unusual features. First, an atypical mode of nucleotide binding that results in unusual relative positioning of the two helicase subdomains. Second, an additional β-hairpin in the second helicase subdomain and an unusual helical hairpin in the Zn2+ binding domain. Modelling of the WRN helicase in complex with DNA suggests roles for these features in the binding of alternative DNA structures. NMR analysis shows a weak interaction between the HRDC domain and the helicase core, indicating a possible biological role for this association. Together, this study will facilitate the structure-based development of inhibitors against WRN helicase.
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Affiliation(s)
- Joseph A Newman
- Structural Genomics Consortium, University of Oxford, Oxford, UK
| | | | - Simone Lieb
- Boehringer Ingelheim RCV GmbH & Co KG, Vienna, Austria
| | | | - Katja Hauer
- Boehringer Ingelheim RCV GmbH & Co KG, Vienna, Austria
| | - Patrick Werni
- Boehringer Ingelheim RCV GmbH & Co KG, Vienna, Austria
| | | | - Jark Böttcher
- Boehringer Ingelheim RCV GmbH & Co KG, Vienna, Austria
| | - John R Engen
- Department of Chemistry and Chemical Biology, Northeastern University, Boston, MA, USA
| | - Klaus Rumpel
- Boehringer Ingelheim RCV GmbH & Co KG, Vienna, Austria
| | | | | | - Opher Gileadi
- Structural Genomics Consortium, University of Oxford, Oxford, UK
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15
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Oka Y, Hamada M, Nakazawa Y, Muramatsu H, Okuno Y, Higasa K, Shimada M, Takeshima H, Hanada K, Hirano T, Kawakita T, Sakaguchi H, Ichimura T, Ozono S, Yuge K, Watanabe Y, Kotani Y, Yamane M, Kasugai Y, Tanaka M, Suganami T, Nakada S, Mitsutake N, Hara Y, Kato K, Mizuno S, Miyake N, Kawai Y, Tokunaga K, Nagasaki M, Kito S, Isoyama K, Onodera M, Kaneko H, Matsumoto N, Matsuda F, Matsuo K, Takahashi Y, Mashimo T, Kojima S, Ogi T. Digenic mutations in ALDH2 and ADH5 impair formaldehyde clearance and cause a multisystem disorder, AMeD syndrome. SCIENCE ADVANCES 2020; 6:6/51/eabd7197. [PMID: 33355142 DOI: 10.1126/sciadv.abd7197] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Accepted: 11/23/2020] [Indexed: 06/12/2023]
Abstract
Rs671 in the aldehyde dehydrogenase 2 gene (ALDH2) is the cause of Asian alcohol flushing response after drinking. ALDH2 detoxifies endogenous aldehydes, which are the major source of DNA damage repaired by the Fanconi anemia pathway. Here, we show that the rs671 defective allele in combination with mutations in the alcohol dehydrogenase 5 gene, which encodes formaldehyde dehydrogenase (ADH5FDH ), causes a previously unidentified disorder, AMeD (aplastic anemia, mental retardation, and dwarfism) syndrome. Cellular studies revealed that a decrease in the formaldehyde tolerance underlies a loss of differentiation and proliferation capacity of hematopoietic stem cells. Moreover, Adh5-/-Aldh2 E506K/E506K double-deficient mice recapitulated key clinical features of AMeDS, showing short life span, dwarfism, and hematopoietic failure. Collectively, our results suggest that the combined deficiency of formaldehyde clearance mechanisms leads to the complex clinical features due to overload of formaldehyde-induced DNA damage, thereby saturation of DNA repair processes.
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Affiliation(s)
- Yasuyoshi Oka
- Department of Genetics, Research Institute of Environmental Medicine (RIeM), Nagoya University, Nagoya, Japan
- Department of Human Genetics and Molecular Biology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Motoharu Hamada
- Department of Pediatrics, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Yuka Nakazawa
- Department of Genetics, Research Institute of Environmental Medicine (RIeM), Nagoya University, Nagoya, Japan
- Department of Human Genetics and Molecular Biology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Hideki Muramatsu
- Department of Pediatrics, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Yusuke Okuno
- Department of Pediatrics, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Koichiro Higasa
- Department of Genome Analysis, Institute of Biomedical Science, Kansai Medical University, Osaka, Japan
- Center for Genomic Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Mayuko Shimada
- Department of Genetics, Research Institute of Environmental Medicine (RIeM), Nagoya University, Nagoya, Japan
- Department of Human Genetics and Molecular Biology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Honoka Takeshima
- Department of Genetics, Research Institute of Environmental Medicine (RIeM), Nagoya University, Nagoya, Japan
- Department of Human Genetics and Molecular Biology, Nagoya University Graduate School of Medicine, Nagoya, Japan
- School of Medicine, Nagoya University, Nagoya, Japan
| | - Katsuhiro Hanada
- Clinical Engineering Research Center, Faculty of Medicine, Oita University, Yufu, Japan
| | - Taichi Hirano
- Department of Hematology, National Hospital Organization, Kumamoto Medical Center, Kumamoto, Japan
| | - Toshiro Kawakita
- Department of Hematology, National Hospital Organization, Kumamoto Medical Center, Kumamoto, Japan
| | - Hirotoshi Sakaguchi
- Department of Hematology and Oncology, Children Medical Center, Japanese Red Cross Nagoya First Hospital, Nagoya, Japan
| | - Takuya Ichimura
- Department of Pediatrics, Graduate School of Medicine, Yamaguchi University, Ube, Japan
| | - Shuichi Ozono
- Department of Pediatrics and Child Health, School of Medicine, Kurume University, Kurume, Japan
| | - Kotaro Yuge
- Department of Pediatrics and Child Health, School of Medicine, Kurume University, Kurume, Japan
| | - Yoriko Watanabe
- Department of Pediatrics and Child Health, School of Medicine, Kurume University, Kurume, Japan
| | - Yuko Kotani
- Institute of Experimental Animal Sciences, Graduate School of Medicine, Osaka University, Osaka, Japan
- Genome Editing Research and Development (R&D) Center, Graduate School of Medicine, Osaka University, Osaka, Japan
| | - Mutsumi Yamane
- Center for Animal Research and Education, Nagoya University, Nagoya, Japan
| | - Yumiko Kasugai
- Division of Cancer Epidemiology and Prevention, Aichi Cancer Center Research Institute, Nagoya, Japan
| | - Miyako Tanaka
- Department of Molecular Medicine and Metabolism, Research Institute of Environmental Medicine (RIeM), Nagoya University, Nagoya, Japan
- Department of Immunometabolism, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Takayoshi Suganami
- Department of Molecular Medicine and Metabolism, Research Institute of Environmental Medicine (RIeM), Nagoya University, Nagoya, Japan
- Department of Immunometabolism, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Shinichiro Nakada
- Department of Bioregulation and Cellular Response, Graduate School of Medicine, Osaka University, Osaka, Japan
- Institute for Advanced Co-Creation Studies, Osaka University, Osaka, Japan
| | - Norisato Mitsutake
- Department of Radiation Medical Sciences, Atomic Bomb Disease Institute, Nagasaki University, Nagasaki, Japan
| | - Yuichiro Hara
- Department of Genetics, Research Institute of Environmental Medicine (RIeM), Nagoya University, Nagoya, Japan
- Department of Human Genetics and Molecular Biology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Kohji Kato
- Department of Genetics, Research Institute of Environmental Medicine (RIeM), Nagoya University, Nagoya, Japan
- Department of Human Genetics and Molecular Biology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Seiji Mizuno
- Department of Pediatrics, Aichi Developmental Disability Center, Kasugai, Japan
| | - Noriko Miyake
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama, Japan
| | - Yosuke Kawai
- Department of Human Genetics, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
- Department of Integrative Genomics, Tohoku Medical Megabank Organization, Tohoku University, Sendai, Japan
| | - Katsushi Tokunaga
- Department of Human Genetics, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Masao Nagasaki
- Department of Integrative Genomics, Tohoku Medical Megabank Organization, Tohoku University, Sendai, Japan
- Human Biosciences Unit for the Top Global Course Center for the Promotion of Interdisciplinary Education and Research, Kyoto University, Kyoto, Japan
| | - Seiji Kito
- Center for Animal Research and Education, Nagoya University, Nagoya, Japan
| | - Keiichi Isoyama
- Department of Pediatrics, Showa University Fujigaoka Hospital, Yokohama, Japan
| | - Masafumi Onodera
- Division of Immunology, National Center for Child Health and Development, Tokyo, Japan
| | - Hideo Kaneko
- Department of Clinical Research, National Hospital Organization, Nagara Medical Center, Gifu, Japan
| | - Naomichi Matsumoto
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama, Japan
| | - Fumihiko Matsuda
- Center for Genomic Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Keitaro Matsuo
- Division of Cancer Epidemiology and Prevention, Aichi Cancer Center Research Institute, Nagoya, Japan
- Department of Epidemiology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Yoshiyuki Takahashi
- Department of Pediatrics, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Tomoji Mashimo
- Institute of Experimental Animal Sciences, Graduate School of Medicine, Osaka University, Osaka, Japan
- Genome Editing Research and Development (R&D) Center, Graduate School of Medicine, Osaka University, Osaka, Japan
- Division of Animal Genetics, Laboratory Animal Research Center, Institute of Medical Science, The University of Tokyo, Tokyo, Japan
| | - Seiji Kojima
- Department of Pediatrics, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Tomoo Ogi
- Department of Genetics, Research Institute of Environmental Medicine (RIeM), Nagoya University, Nagoya, Japan.
- Department of Human Genetics and Molecular Biology, Nagoya University Graduate School of Medicine, Nagoya, Japan
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16
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Komari CJ, Guttman AO, Carr SR, Trachtenberg TL, Orloff EA, Haas AV, Patrick AR, Chowdhary S, Waldman BC, Waldman AS. Alteration of genetic recombination and double-strand break repair in human cells by progerin expression. DNA Repair (Amst) 2020; 96:102975. [PMID: 33010688 DOI: 10.1016/j.dnarep.2020.102975] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 08/21/2020] [Accepted: 09/04/2020] [Indexed: 01/04/2023]
Abstract
Hutchinson-Gilford Progeria Syndrome (HGPS) is a rare autosomal, dominant genetic condition characterized by many features of accelerated aging. On average, children with HGPS live to about fourteen years of age. The syndrome is commonly caused by a point mutation in the LMNA gene which normally codes for lamin A and its splice variant lamin C, components of the nuclear lamina. The LMNA mutation alters splicing, leading to production of a truncated, farnesylated form of lamin A referred to as "progerin." Progerin is also expressed at very low levels in healthy individuals and appears to play a role in normal aging. HGPS is associated with an accumulation of genomic DNA double-strand breaks (DSBs), suggesting corruption of DNA repair. In this work, we investigated the influence of progerin expression on DSB repair in the human genome at the nucleotide level. We used a model system that involves a reporter DNA substrate inserted in the genome of cultured human cells. A DSB could be induced within the substrate through exogenous expression of endonuclease I-SceI, and DSB repair events occurring via either homologous recombination (HR) or nonhomologous end-joining (NHEJ) were recoverable. Additionally, spontaneous HR events were recoverable in the absence of artificial DSB induction. We compared DSB repair and spontaneous HR in cells overexpressing progerin versus cells expressing no progerin. We report that overexpression of progerin correlated with an increase in DSB repair via NHEJ relative to HR, as well as an increased fraction of HR events occurring via gene conversion. Progerin also engendered an apparent increase in spontaneous HR events, with a highly significant shift toward gene conversion events, and an increase in DNA amplification events. Such influences of progerin on DNA transactions may impact genome stability and contribute to aging.
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Affiliation(s)
- Celina J Komari
- Department of Public Health, University of South Carolina, Columbia, SC 29208, USA
| | - Anne O Guttman
- Department of Exercise Science, University of South Carolina, Columbia, SC 29208, USA
| | - Shelby R Carr
- Department of Exercise Science, University of South Carolina, Columbia, SC 29208, USA
| | - Taylor L Trachtenberg
- Department of Exercise Science, University of South Carolina, Columbia, SC 29208, USA
| | - Elise A Orloff
- Department of Exercise Science, University of South Carolina, Columbia, SC 29208, USA
| | - Ashley V Haas
- Department of Biological Sciences, University of South Carolina, Columbia, SC 29208, USA
| | - Andrew R Patrick
- Department of Biological Sciences, University of South Carolina, Columbia, SC 29208, USA
| | - Sona Chowdhary
- Department of Biological Sciences, University of South Carolina, Columbia, SC 29208, USA
| | - Barbara C Waldman
- Department of Biological Sciences, University of South Carolina, Columbia, SC 29208, USA
| | - Alan S Waldman
- Department of Biological Sciences, University of South Carolina, Columbia, SC 29208, USA.
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17
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Gupta SV, Schmidt KH. Maintenance of Yeast Genome Integrity by RecQ Family DNA Helicases. Genes (Basel) 2020; 11:E205. [PMID: 32085395 PMCID: PMC7074392 DOI: 10.3390/genes11020205] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Revised: 02/11/2020] [Accepted: 02/14/2020] [Indexed: 12/28/2022] Open
Abstract
With roles in DNA repair, recombination, replication and transcription, members of the RecQ DNA helicase family maintain genome integrity from bacteria to mammals. Mutations in human RecQ helicases BLM, WRN and RecQL4 cause incurable disorders characterized by genome instability, increased cancer predisposition and premature adult-onset aging. Yeast cells lacking the RecQ helicase Sgs1 share many of the cellular defects of human cells lacking BLM, including hypersensitivity to DNA damaging agents and replication stress, shortened lifespan, genome instability and mitotic hyper-recombination, making them invaluable model systems for elucidating eukaryotic RecQ helicase function. Yeast and human RecQ helicases have common DNA substrates and domain structures and share similar physical interaction partners. Here, we review the major cellular functions of the yeast RecQ helicases Sgs1 of Saccharomyces cerevisiae and Rqh1 of Schizosaccharomyces pombe and provide an outlook on some of the outstanding questions in the field.
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Affiliation(s)
- Sonia Vidushi Gupta
- Department of Cell Biology, Microbiology and Molecular Biology, University of South, Florida, Tampa, FL 33620, USA;
| | - Kristina Hildegard Schmidt
- Department of Cell Biology, Microbiology and Molecular Biology, University of South, Florida, Tampa, FL 33620, USA;
- Cancer Biology and Evolution Program, H. Lee Moffitt Cancer Center and Research, Institute, Tampa, FL 33612, USA
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18
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Walen KH. Near-Dead Cells to Special Tetraploidy to First Cells to Cancer Diagnostic Morphology: Unlikely Therapy-Gain from For-Profit Industrial Goliath. ACTA ACUST UNITED AC 2020. [DOI: 10.4236/jct.2020.117036] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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19
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Lu L, Jin W, Wang LL. RECQ DNA Helicases and Osteosarcoma. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2020; 1258:37-54. [PMID: 32767233 DOI: 10.1007/978-3-030-43085-6_3] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The RECQ family of DNA helicases is a conserved group of enzymes that plays an important role in maintaining genomic stability. Humans possess five RECQ helicase genes, and mutations in three of them - BLM, WRN, and RECQL4 - are associated with the genetic disorders Bloom syndrome, Werner syndrome, and Rothmund-Thomson syndrome (RTS), respectively. These syndromes share overlapping clinical features, and importantly they are all associated with an increased risk of cancer. Patients with RTS have the highest specific risk of developing osteosarcoma compared to all other cancer predisposition syndromes; therefore, RTS serves as a relevant model to study the pathogenesis and molecular genetics of osteosarcoma. The "tumor suppressor" function of the RECQ helicases continues to be an area of active investigation. This chapter will focus primarily on the known cellular functions of RECQL4 and how these may relate to tumorigenesis, as well as ongoing efforts to understand RECQL4's functions in vivo using animal models. Understanding the RECQ pathways will provide insight into avenues for novel cancer therapies in the future.
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Affiliation(s)
- Linchao Lu
- Department of Pediatrics, Section of Hematology/Oncology, Texas Children's Cancer Center, Baylor College of Medicine, Houston, TX, USA.
| | - Weidong Jin
- Department of Pediatrics, Section of Hematology/Oncology, Texas Children's Cancer Center, Baylor College of Medicine, Houston, TX, USA
| | - Lisa L Wang
- Department of Pediatrics, Section of Hematology/Oncology, Texas Children's Cancer Center, Baylor College of Medicine, Houston, TX, USA.
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20
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Sleiman S, Dragon F. Recent Advances on the Structure and Function of RNA Acetyltransferase Kre33/NAT10. Cells 2019; 8:cells8091035. [PMID: 31491951 PMCID: PMC6770127 DOI: 10.3390/cells8091035] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Revised: 08/23/2019] [Accepted: 08/25/2019] [Indexed: 02/07/2023] Open
Abstract
Ribosome biogenesis is one of the most energy demanding processes in the cell. In eukaryotes, the main steps of this process occur in the nucleolus and include pre-ribosomal RNA (pre-rRNA) processing, post-transcriptional modifications, and assembly of many non-ribosomal factors and ribosomal proteins in order to form mature and functional ribosomes. In yeast and humans, the nucleolar RNA acetyltransferase Kre33/NAT10 participates in different maturation events, such as acetylation and processing of 18S rRNA, and assembly of the 40S ribosomal subunit. Here, we review the structural and functional features of Kre33/NAT10 RNA acetyltransferase, and we underscore the importance of this enzyme in ribosome biogenesis, as well as in acetylation of non-ribosomal targets. We also report on the role of human NAT10 in Hutchinson-Gilford progeria syndrome.
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Affiliation(s)
- Sophie Sleiman
- Département des Sciences Biologiques and Centre d'Excellence en Recherche sur les Maladies Orphelines-Fondation Courtois (CERMO-FC), Université du Québec à Montréal, Montréal, QC H3C 3P8, Canada.
| | - Francois Dragon
- Département des Sciences Biologiques and Centre d'Excellence en Recherche sur les Maladies Orphelines-Fondation Courtois (CERMO-FC), Université du Québec à Montréal, Montréal, QC H3C 3P8, Canada.
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21
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Seol Y, Harami GM, Kovács M, Neuman KC. Homology sensing via non-linear amplification of sequence-dependent pausing by RecQ helicase. eLife 2019; 8:e45909. [PMID: 31464683 PMCID: PMC6773442 DOI: 10.7554/elife.45909] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2019] [Accepted: 08/28/2019] [Indexed: 12/25/2022] Open
Abstract
RecQ helicases promote genomic stability through their unique ability to suppress illegitimate recombination and resolve recombination intermediates. These DNA structure-specific activities of RecQ helicases are mediated by the helicase-and-RNAseD like C-terminal (HRDC) domain, via unknown mechanisms. Here, employing single-molecule magnetic tweezers and rapid kinetic approaches we establish that the HRDC domain stabilizes intrinsic, sequence-dependent, pauses of the core helicase (lacking the HRDC) in a DNA geometry-dependent manner. We elucidate the core unwinding mechanism in which the unwinding rate depends on the stability of the duplex DNA leading to transient sequence-dependent pauses. We further demonstrate a non-linear amplification of these transient pauses by the controlled binding of the HRDC domain. The resulting DNA sequence- and geometry-dependent pausing may underlie a homology sensing mechanism that allows rapid disruption of unstable (illegitimate) and stabilization of stable (legitimate) DNA strand invasions, which suggests an intrinsic mechanism of recombination quality control by RecQ helicases.
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Affiliation(s)
- Yeonee Seol
- Laboratory of Single Molecule BiophysicsNational Heart, Lung, and Blood Institute, National Institutes of HealthBethesdaUnited States
| | - Gábor M Harami
- Department of Biochemistry, ELTE-MTA “Momentum” Motor Enzymology Research GroupEötvös Loránd UniversityBudapestHungary
| | - Mihály Kovács
- Department of Biochemistry, ELTE-MTA “Momentum” Motor Enzymology Research GroupEötvös Loránd UniversityBudapestHungary
- Department of Biochemistry, MTA-ELTE Motor Pharmacology Research GroupEötvös Loránd UniversityBudapestHungary
| | - Keir C Neuman
- Laboratory of Single Molecule BiophysicsNational Heart, Lung, and Blood Institute, National Institutes of HealthBethesdaUnited States
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22
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Chen Y, Zhao J, Duan Z, Gong T, Chen W, Wang S, Xu H. miR‑27b‑3p and miR‑607 cooperatively regulate BLM gene expression by directly targeting the 3'‑UTR in PC3 cells. Mol Med Rep 2019; 19:4819-4831. [PMID: 30957187 PMCID: PMC6522798 DOI: 10.3892/mmr.2019.10135] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Accepted: 03/26/2019] [Indexed: 02/07/2023] Open
Abstract
BLM RecQ like helicase (BLM) has a pivotal role in genetic recombination, transcription, DNA replication and DNA repair, which presents the possibility of using BLM as an anti-cancer target for treatment. However, the post-transcriptional control regulation of BLM gene expression is not fully understood and limits the application of drugs targeting BLM for carcinoma therapy in the future. MicroRNAs (miRNAs) inhibit gene expression through interaction with the 3′ untranslated region (3′-UTR) of mRNA at the post-transcriptional stage. Therefore, the current study screened for miRNAs that regulate BLM gene expression, with software predicting that miRNA (miR)-27b-3p, miR-607, miR-361-3p, miR-628-5p and miR-338-3p. BLM gene expression levels in the PC3 prostate cancer cell line and RWPE-2 normal prostate epithelium cell line were detected by reverse transcription-quantitative PCR. Additionally, BLM mRNA levels were following miRNA overexpression for 24 and 48 h. For further miRNA filtration and validation, a dual-luciferase reporter system and western blot analysis were performed, which demonstrated that miR-27b-3p and miR-607 reduce BLM gene expression by directly targeting the BLM mRNA 3′-UTR. A Box-Behnken design experiment suggested that miR-27b-3p and miR-607 have synergetic mutual effects on BLM gene expression. Finally, the suppressive effect of miR-27b-3p and miR-607 on PC3 cell proliferation, colony formation, migration and invasion indicated the benefit of studying BLM as a drug target in cancer. In conclusion, the findings of the current provide evidence that miR-27b-3p and miR-607 have an oncosuppressive function in PC3 cells and cooperatively downregulate BLM expression at the post-transcriptional level.
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Affiliation(s)
- Yinglian Chen
- Key Laboratory of Animal Genetics, Breeding and Reproduction in The Plateau Mountainous Region, Ministry of Education, Guizhou University, Guiyang, Guizhou 550025, P.R. China
| | - Jiafu Zhao
- Key Laboratory of Animal Genetics, Breeding and Reproduction in The Plateau Mountainous Region, Ministry of Education, Guizhou University, Guiyang, Guizhou 550025, P.R. China
| | - Zhiqiang Duan
- Key Laboratory of Animal Genetics, Breeding and Reproduction in The Plateau Mountainous Region, Ministry of Education, Guizhou University, Guiyang, Guizhou 550025, P.R. China
| | - Ting Gong
- Key Laboratory of Animal Genetics, Breeding and Reproduction in The Plateau Mountainous Region, Ministry of Education, Guizhou University, Guiyang, Guizhou 550025, P.R. China
| | - Wei Chen
- Key Laboratory of Animal Genetics, Breeding and Reproduction in The Plateau Mountainous Region, Ministry of Education, Guizhou University, Guiyang, Guizhou 550025, P.R. China
| | - Sainan Wang
- Key Laboratory of Animal Genetics, Breeding and Reproduction in The Plateau Mountainous Region, Ministry of Education, Guizhou University, Guiyang, Guizhou 550025, P.R. China
| | - Houqiang Xu
- Key Laboratory of Animal Genetics, Breeding and Reproduction in The Plateau Mountainous Region, Ministry of Education, Guizhou University, Guiyang, Guizhou 550025, P.R. China
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23
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Castagna A, Gareri P, Falvo F, Sestito S, Rocca M, Pensabene L, Concolino D, Coppolino G, Ruotolo G. Werner syndrome: a rare mutation. Aging Clin Exp Res 2019; 31:425-429. [PMID: 29876830 DOI: 10.1007/s40520-018-0982-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Accepted: 05/30/2018] [Indexed: 10/14/2022]
Affiliation(s)
- Alberto Castagna
- Center for Cognitive Disorders and Dementia, DSS Catanzaro Lido, ASP Catanzaro, Viale Crotone, 88100, Catanzaro, Italy
| | - Pietro Gareri
- Center for Cognitive Disorders and Dementia, DSS Catanzaro Lido, ASP Catanzaro, Viale Crotone, 88100, Catanzaro, Italy.
| | - Francesca Falvo
- Department of Pediatrics, University Magna Graecia of Catanzaro, Catanzaro, Italy
| | - Simona Sestito
- Department of Pediatrics, University Magna Graecia of Catanzaro, Catanzaro, Italy
| | - Maurizio Rocca
- Center for Cognitive Disorders and Dementia, DSS Catanzaro Lido, ASP Catanzaro, Viale Crotone, 88100, Catanzaro, Italy
| | - Licia Pensabene
- Department of Pediatrics, University Magna Graecia of Catanzaro, Catanzaro, Italy
| | - Daniela Concolino
- Department of Pediatrics, University Magna Graecia of Catanzaro, Catanzaro, Italy
| | - Giuseppe Coppolino
- Nephrology and Dialysis Unit, "Pugliese-Ciaccio" Hospital of Catanzaro, Catanzaro, Italy
| | - Giovanni Ruotolo
- SOC Geriatrics, Azienda Ospedaliera Pugliese-Ciaccio, Catanzaro, Italy
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24
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Abstract
IMPACT STATEMENT This review provides various genetic and cell line data previously published in a way to explain how cellular stress can lead into genetic instability.
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Affiliation(s)
- Jung Joo Moon
- 1 JS Yoon Memorial Cancer Research Institute LLC, Lutherville, MD 2109, USA
| | - Alexander Lu
- 1 JS Yoon Memorial Cancer Research Institute LLC, Lutherville, MD 2109, USA
| | - Chulso Moon
- 1 JS Yoon Memorial Cancer Research Institute LLC, Lutherville, MD 2109, USA.,2 Department of Otolaryngology-Head and Neck Surgery, The Johns Hopkins Medical Institution, Baltimore, MD 21205, USA
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25
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Tanabe K, Awane R, Shoda T, Yamazoe K, Inoue YH. Mutations in mxc Tumor-Suppressor Gene Induce Chromosome Instability in Drosophila Male Meiosis. Cell Struct Funct 2019; 44:121-135. [DOI: 10.1247/csf.19022] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Affiliation(s)
- Karin Tanabe
- Department of Insect Biomedical Research, Center for Advanced Insect Research Promotion, Kyoto Institute of Technology
| | - Rie Awane
- Department of Insect Biomedical Research, Center for Advanced Insect Research Promotion, Kyoto Institute of Technology
| | - Tsuyoshi Shoda
- Department of Insect Biomedical Research, Center for Advanced Insect Research Promotion, Kyoto Institute of Technology
| | - Kanta Yamazoe
- Department of Insect Biomedical Research, Center for Advanced Insect Research Promotion, Kyoto Institute of Technology
| | - Yoshihiro H. Inoue
- Department of Insect Biomedical Research, Center for Advanced Insect Research Promotion, Kyoto Institute of Technology
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26
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The Unresolved Problem of DNA Bridging. Genes (Basel) 2018; 9:genes9120623. [PMID: 30545131 PMCID: PMC6316547 DOI: 10.3390/genes9120623] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Revised: 12/08/2018] [Accepted: 12/10/2018] [Indexed: 12/31/2022] Open
Abstract
Accurate duplication and transmission of identical genetic information into offspring cells lies at the heart of a cell division cycle. During the last stage of cellular division, namely mitosis, the fully replicated DNA molecules are condensed into X-shaped chromosomes, followed by a chromosome separation process called sister chromatid disjunction. This process allows for the equal partition of genetic material into two newly born daughter cells. However, emerging evidence has shown that faithful chromosome segregation is challenged by the presence of persistent DNA intertwining structures generated during DNA replication and repair, which manifest as so-called ultra-fine DNA bridges (UFBs) during anaphase. Undoubtedly, failure to disentangle DNA linkages poses a severe threat to mitosis and genome integrity. This review will summarize the possible causes of DNA bridges, particularly sister DNA inter-linkage structures, in an attempt to explain how they may be processed and how they influence faithful chromosome segregation and the maintenance of genome stability.
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27
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Wang AS, Dreesen O. Biomarkers of Cellular Senescence and Skin Aging. Front Genet 2018; 9:247. [PMID: 30190724 PMCID: PMC6115505 DOI: 10.3389/fgene.2018.00247] [Citation(s) in RCA: 221] [Impact Index Per Article: 36.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Accepted: 06/22/2018] [Indexed: 02/06/2023] Open
Abstract
Cellular senescence is an irreversible growth arrest that occurs as a result of different damaging stimuli, including DNA damage, telomere shortening and dysfunction or oncogenic stress. Senescent cells exert a pleotropic effect on development, tissue aging and regeneration, inflammation, wound healing and tumor suppression. Strategies to remove senescent cells from aging tissues or preneoplastic lesions can delay tissue dysfunction and lead to increased healthspan. However, a significant hurdle in the aging field has been the identification of a universal biomarker that facilitates the unequivocal detection and quantification of senescent cell types in vitro and in vivo. Mammalian skin is the largest organ of the human body and consists of different cell types and compartments. Skin provides a physical barrier against harmful microbes, toxins, and protects us from ultraviolet radiation. Increasing evidence suggests that senescent cells accumulate in chronologically aged and photoaged skin; and may contribute to age-related skin changes and pathologies. Here, we highlight current biomarkers to detect senescent cells and review their utility in the context of skin aging. In particular, we discuss the efficacy of biomarkers to detect senescence within different skin compartments and cell types, and how they may contribute to myriad manifestations of skin aging and age-related skin pathologies.
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Affiliation(s)
- Audrey S Wang
- Cell Ageing, Skin Research Institute of Singapore (SRIS), A∗STAR, Singapore, Singapore
| | - Oliver Dreesen
- Cell Ageing, Skin Research Institute of Singapore (SRIS), A∗STAR, Singapore, Singapore.,Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore
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28
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La Torre M, Merigliano C, Burla R, Mottini C, Zanetti G, Del Giudice S, Carcuro M, Virdia I, Bucciarelli E, Manni I, Vinciguerra GR, Piaggio G, Riminucci M, Cumano A, Bartolazzi A, Vernì F, Soddu S, Gatti M, Saggio I. Mice with reduced expression of the telomere-associated protein Ft1 develop p53-sensitive progeroid traits. Aging Cell 2018; 17:e12730. [PMID: 29635765 PMCID: PMC6052474 DOI: 10.1111/acel.12730] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/20/2017] [Indexed: 01/14/2023] Open
Abstract
Human AKTIP and mouse Ft1 are orthologous ubiquitin E2 variant proteins involved in telomere maintenance and DNA replication. AKTIP also interacts with A‐ and B‐type lamins. These features suggest that Ft1 may be implicated in aging regulatory pathways. Here, we show that cells derived from hypomorph Ft1 mutant (Ft1kof/kof) mice exhibit telomeric defects and that Ft1kof/kof animals develop progeroid traits, including impaired growth, skeletal and skin defects, abnormal heart tissue, and sterility. We also demonstrate a genetic interaction between Ft1 and p53. The analysis of mice carrying mutations in both Ft1 and p53 (Ft1kof/kof; p53ko/ko and Ft1kof/kof; p53+/ko) showed that reduction in p53 rescues the progeroid traits of Ft1 mutants, suggesting that they are at least in part caused by a p53‐dependent DNA damage response. Conversely, Ft1 reduction alters lymphomagenesis in p53 mutant mice. These results identify Ft1 as a new player in the aging process and open the way to the analysis of its interactions with other progeria genes using the mouse model.
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Affiliation(s)
- Mattia La Torre
- Dipartimento di Biologia e Biotecnologie “C. Darwin”; Sapienza Università di Roma; Rome Italy
| | - Chiara Merigliano
- Dipartimento di Biologia e Biotecnologie “C. Darwin”; Sapienza Università di Roma; Rome Italy
| | - Romina Burla
- Dipartimento di Biologia e Biotecnologie “C. Darwin”; Sapienza Università di Roma; Rome Italy
| | - Carla Mottini
- Dipartimento di Biologia e Biotecnologie “C. Darwin”; Sapienza Università di Roma; Rome Italy
| | - Giorgia Zanetti
- Dipartimento di Biologia e Biotecnologie “C. Darwin”; Sapienza Università di Roma; Rome Italy
| | - Simona Del Giudice
- Dipartimento di Biologia e Biotecnologie “C. Darwin”; Sapienza Università di Roma; Rome Italy
| | - Mariateresa Carcuro
- Dipartimento di Biologia e Biotecnologie “C. Darwin”; Sapienza Università di Roma; Rome Italy
| | - Ilaria Virdia
- Dipartimento di Ricerca, Diagnostica Avanzata e Innovazione Tecnologica; Istituto Nazionale Tumori Regina Elena; Rome Italy
| | | | - Isabella Manni
- Dipartimento di Ricerca, Diagnostica Avanzata e Innovazione Tecnologica; Istituto Nazionale Tumori Regina Elena; Rome Italy
| | | | - Giulia Piaggio
- Dipartimento di Ricerca, Diagnostica Avanzata e Innovazione Tecnologica; Istituto Nazionale Tumori Regina Elena; Rome Italy
| | - Mara Riminucci
- Dipartimento di Medicina Molecolare; Sapienza Università di Roma; Rome Italy
| | - Ana Cumano
- Lymphopoiesis Unit; Institut Pasteur; Paris France
| | | | - Fiammetta Vernì
- Dipartimento di Biologia e Biotecnologie “C. Darwin”; Sapienza Università di Roma; Rome Italy
| | - Silvia Soddu
- Dipartimento di Ricerca, Diagnostica Avanzata e Innovazione Tecnologica; Istituto Nazionale Tumori Regina Elena; Rome Italy
| | - Maurizio Gatti
- Dipartimento di Biologia e Biotecnologie “C. Darwin”; Sapienza Università di Roma; Rome Italy
- Istituto di Biologia e Patologia Molecolari del CNR; Rome Italy
| | - Isabella Saggio
- Dipartimento di Biologia e Biotecnologie “C. Darwin”; Sapienza Università di Roma; Rome Italy
- Istituto di Biologia e Patologia Molecolari del CNR; Rome Italy
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29
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Burla R, La Torre M, Merigliano C, Vernì F, Saggio I. Genomic instability and DNA replication defects in progeroid syndromes. Nucleus 2018; 9:368-379. [PMID: 29936894 PMCID: PMC7000143 DOI: 10.1080/19491034.2018.1476793] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Progeroid syndromes induced by mutations in lamin A or in its interactors – named progeroid laminopathies – are model systems for the dissection of the molecular pathways causing physiological and premature aging. A large amount of data, based mainly on the Hutchinson Gilford Progeria syndrome (HGPS), one of the best characterized progeroid laminopathy, has highlighted the role of lamins in multiple DNA activities, including replication, repair, chromatin organization and telomere function. On the other hand, the phenotypes generated by mutations affecting genes directly acting on DNA function, as mutations in the helicases WRN and BLM or in the polymerase polδ, share many of the traits of progeroid laminopathies. These evidences support the hypothesis of a concerted implication of DNA function and lamins in aging. We focus here on these aspects to contribute to the comprehension of the driving forces acting in progeroid syndromes and premature aging.
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Affiliation(s)
- Romina Burla
- a Dipartimento di Biologia e Biotecnologie "C. Darwin" , Sapienza Università di Roma , Roma , Italy.,b Istituto di Biologia e Patologia Molecolari del CNR , Rome , Italy
| | - Mattia La Torre
- a Dipartimento di Biologia e Biotecnologie "C. Darwin" , Sapienza Università di Roma , Roma , Italy.,b Istituto di Biologia e Patologia Molecolari del CNR , Rome , Italy
| | - Chiara Merigliano
- a Dipartimento di Biologia e Biotecnologie "C. Darwin" , Sapienza Università di Roma , Roma , Italy
| | - Fiammetta Vernì
- a Dipartimento di Biologia e Biotecnologie "C. Darwin" , Sapienza Università di Roma , Roma , Italy
| | - Isabella Saggio
- a Dipartimento di Biologia e Biotecnologie "C. Darwin" , Sapienza Università di Roma , Roma , Italy.,b Istituto di Biologia e Patologia Molecolari del CNR , Rome , Italy.,c Istituto Pasteur Fondazione Cenci Bolognetti , Rome , Italy
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30
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Maity J, Das B, Bohr VA, Karmakar P. Acidic domain of WRNp is critical for autophagy and up-regulates age associated proteins. DNA Repair (Amst) 2018; 68:1-11. [PMID: 29800817 DOI: 10.1016/j.dnarep.2018.05.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2018] [Revised: 04/06/2018] [Accepted: 05/17/2018] [Indexed: 01/07/2023]
Abstract
Impaired autophagy may be associated with normal and pathological aging. Here we explore a link between autophagy and domain function of Werner protein (WRNp). Werner (WRN) mutant cell lines AG11395, AG05229 and normal aged fibroblast AG13129 display a deficient response to tunicamycin mediated endoplasmic reticulum (ER) stress induced autophagy compared to clinically unaffected GM00637 and normal young fibroblast GM03440. Cellular endoplasmic reticulum (ER) stress mediated autophagy in WS and normal aged cells is restored after transfection with wild type full length WRN, but deletion of the acidic domain from wild type WRN fails to restore autophagy. The acidic domain of WRNp was shown to regulate its transcriptional activity, and here, we show that it affects the transcription of certain proteins involved in autophagy and aging. Furthermore, siRNA mediated silencing of WRN in normal fibroblast WI-38 resulted in decrease of age related proteins Lamin A/C and Mre11.
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Affiliation(s)
- Jyotirindra Maity
- Department of Life Science and Biotechnology, Jadavpur University, Kolkata, 700032, India
| | - Biswadip Das
- Department of Life Science and Biotechnology, Jadavpur University, Kolkata, 700032, India
| | - Vilhelm A Bohr
- Laboratory of Molecular Gerontology, National Institute on Aging, National Institutes of Health, Baltimore, MD, 21224, USA
| | - Parimal Karmakar
- Department of Life Science and Biotechnology, Jadavpur University, Kolkata, 700032, India.
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31
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Newman JA, Aitkenhead H, Savitsky P, Gileadi O. Insights into the RecQ helicase mechanism revealed by the structure of the helicase domain of human RECQL5. Nucleic Acids Res 2017; 45:4231-4243. [PMID: 28100692 PMCID: PMC5397160 DOI: 10.1093/nar/gkw1362] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2016] [Accepted: 01/03/2017] [Indexed: 12/17/2022] Open
Abstract
RecQ helicases are important maintainers of genome integrity with distinct roles in almost every cellular process requiring access to DNA. RECQL5 is one of five human RecQ proteins and is particularly versatile in this regard, forming protein complexes with a diverse set of cellular partners in order to coordinate its helicase activity to various processes including replication, recombination and DNA repair. In this study, we have determined crystal structures of the core helicase domain of RECQL5 both with and without the nucleotide ADP in two distinctly different (‘Open’ and ‘Closed’) conformations. Small angle X-ray scattering studies show that the ‘Open’ form of the protein predominates in solution and we discuss implications of this with regards to the RECQL5 mechanism and conformational changes. We have measured the ATPase, helicase and DNA binding properties of various RECQL5 constructs and variants and discuss the role of these regions and residues in the various RECQL5 activities. Finally, we have performed a systematic comparison of the RECQL5 structures with other RecQ family structures and based on these comparisons we have constructed a model for the mechano-chemical cycle of the common catalytic core of these helicases.
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Affiliation(s)
- Joseph A Newman
- Structural Genomics Consortium, University of Oxford, ORCRB, Roosevelt Drive, Oxford OX3 7DQ, UK
| | - Hazel Aitkenhead
- Structural Genomics Consortium, University of Oxford, ORCRB, Roosevelt Drive, Oxford OX3 7DQ, UK
| | - Pavel Savitsky
- Structural Genomics Consortium, University of Oxford, ORCRB, Roosevelt Drive, Oxford OX3 7DQ, UK
| | - Opher Gileadi
- Structural Genomics Consortium, University of Oxford, ORCRB, Roosevelt Drive, Oxford OX3 7DQ, UK.,Structural Genomics Consortium, State University of Campinas, Campinas SP 13083-886, Brazil
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32
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Walsh MF, Chang VY, Kohlmann WK, Scott HS, Cunniff C, Bourdeaut F, Molenaar JJ, Porter CC, Sandlund JT, Plon SE, Wang LL, Savage SA. Recommendations for Childhood Cancer Screening and Surveillance in DNA Repair Disorders. Clin Cancer Res 2017; 23:e23-e31. [PMID: 28572264 PMCID: PMC5697784 DOI: 10.1158/1078-0432.ccr-17-0465] [Citation(s) in RCA: 73] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2017] [Revised: 03/30/2017] [Accepted: 04/20/2017] [Indexed: 01/09/2023]
Abstract
DNA repair syndromes are heterogeneous disorders caused by pathogenic variants in genes encoding proteins key in DNA replication and/or the cellular response to DNA damage. The majority of these syndromes are inherited in an autosomal-recessive manner, but autosomal-dominant and X-linked recessive disorders also exist. The clinical features of patients with DNA repair syndromes are highly varied and dependent on the underlying genetic cause. Notably, all patients have elevated risks of syndrome-associated cancers, and many of these cancers present in childhood. Although it is clear that the risk of cancer is increased, there are limited data defining the true incidence of cancer and almost no evidence-based approaches to cancer surveillance in patients with DNA repair disorders. This article is the product of the October 2016 AACR Childhood Cancer Predisposition Workshop, which brought together experts from around the world to discuss and develop cancer surveillance guidelines for children with cancer-prone disorders. Herein, we focus on the more common of the rare DNA repair disorders: ataxia telangiectasia, Bloom syndrome, Fanconi anemia, dyskeratosis congenita, Nijmegen breakage syndrome, Rothmund-Thomson syndrome, and Xeroderma pigmentosum. Dedicated syndrome registries and a combination of basic science and clinical research have led to important insights into the underlying biology of these disorders. Given the rarity of these disorders, it is recommended that centralized centers of excellence be involved directly or through consultation in caring for patients with heritable DNA repair syndromes. Clin Cancer Res; 23(11); e23-e31. ©2017 AACRSee all articles in the online-only CCR Pediatric Oncology Series.
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Affiliation(s)
| | - Vivian Y Chang
- University of California, Los Angeles, Los Angeles, California
| | - Wendy K Kohlmann
- Huntsman Cancer Institute, University of Utah, Salt Lake City, Utah
| | - Hamish S Scott
- Department of Genetics and Molecular Pathology, Centre for Cancer Biology, Adelaide, South Australia
| | | | | | - Jan J Molenaar
- Princess Máxima Center for Pediatric Oncology, Amsterdam, the Netherlands
| | | | | | - Sharon E Plon
- Baylor College of Medicine, Texas Children's Hospital, Houston, Texas
| | - Lisa L Wang
- Baylor College of Medicine, Texas Children's Hospital, Houston, Texas
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33
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Malik N, Agarwal P, Tyagi A. Emerging functions of multi-protein complex Mediator with special emphasis on plants. Crit Rev Biochem Mol Biol 2017; 52:475-502. [DOI: 10.1080/10409238.2017.1325830] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Naveen Malik
- National Institute of Plant Genome Research (NIPGR), New Delhi, India
| | - Pinky Agarwal
- National Institute of Plant Genome Research (NIPGR), New Delhi, India
| | - Akhilesh Tyagi
- National Institute of Plant Genome Research (NIPGR), New Delhi, India
- Department of Plant Molecular Biology, University of Delhi South Campus, New Delhi, India
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34
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Shi J, Chen WF, Zhang B, Fan SH, Ai X, Liu NN, Rety S, Xi XG. A helical bundle in the N-terminal domain of the BLM helicase mediates dimer and potentially hexamer formation. J Biol Chem 2017; 292:5909-5920. [PMID: 28228481 DOI: 10.1074/jbc.m116.761510] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Revised: 02/14/2017] [Indexed: 12/11/2022] Open
Abstract
Helicases play a critical role in processes such as replication or recombination by unwinding double-stranded DNA; mutations of these genes can therefore have devastating biological consequences. In humans, mutations in genes of three members of the RecQ family helicases (blm, wrn, and recq4) give rise to three strikingly distinctive clinical phenotypes: Bloom syndrome, Werner syndrome, and Rothmund-Thomson syndrome, respectively. However, the molecular basis for these varying phenotypic outcomes is unclear, in part because a full mechanistic description of helicase activity is lacking. Because the helicase core domains are highly conserved, it has been postulated that functional differences among family members might be explained by significant differences in the N-terminal domains, but these domains are poorly characterized. To help fill this gap, we now describe bioinformatics, biochemical, and structural data for three vertebrate BLM proteins. We pair high resolution crystal structures with SAXS analysis to describe an internal, highly conserved sequence we term the dimerization helical bundle in N-terminal domain (DHBN). We show that, despite the N-terminal domain being loosely structured and potentially lacking a defined three-dimensional structure in general, the DHBN exists as a dimeric structure required for higher order oligomer assembly. Interestingly, the unwinding amplitude and rate decrease as BLM is assembled from dimer into hexamer, and also, the stable DHBN dimer can be dissociated upon ATP hydrolysis. Thus, the structural and biochemical characterizations of N-terminal domains will provide new insights into how the N-terminal domain affects the structural and functional organization of the full BLM molecule.
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Affiliation(s)
- Jing Shi
- From the College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Wei-Fei Chen
- From the College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Bo Zhang
- From the College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - San-Hong Fan
- From the College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Xia Ai
- From the College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Na-Nv Liu
- From the College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Stephane Rety
- the Institut de Biochimie et Chimie des Protéines, CNRS UMR 5086, 7 Passage du Vercors, 69367 Lyon, France, and
| | - Xu-Guang Xi
- From the College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, China, .,the Laboratoire de Biologie et Pharmacologie Appliquée, ENS de Cachan, Université Paris-Saclay, CNRS, 61 Avenue du Président Wilson, 94235 Cachan, France
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Common Chemical Inductors of Replication Stress: Focus on Cell-Based Studies. Biomolecules 2017; 7:biom7010019. [PMID: 28230817 PMCID: PMC5372731 DOI: 10.3390/biom7010019] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2016] [Accepted: 02/10/2017] [Indexed: 01/01/2023] Open
Abstract
DNA replication is a highly demanding process regarding the energy and material supply and must be precisely regulated, involving multiple cellular feedbacks. The slowing down or stalling of DNA synthesis and/or replication forks is referred to as replication stress (RS). Owing to the complexity and requirements of replication, a plethora of factors may interfere and challenge the genome stability, cell survival or affect the whole organism. This review outlines chemical compounds that are known inducers of RS and commonly used in laboratory research. These compounds act on replication by direct interaction with DNA causing DNA crosslinks and bulky lesions (cisplatin), chemical interference with the metabolism of deoxyribonucleotide triphosphates (hydroxyurea), direct inhibition of the activity of replicative DNA polymerases (aphidicolin) and interference with enzymes dealing with topological DNA stress (camptothecin, etoposide). As a variety of mechanisms can induce RS, the responses of mammalian cells also vary. Here, we review the activity and mechanism of action of these compounds based on recent knowledge, accompanied by examples of induced phenotypes, cellular readouts and commonly used doses.
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Adenocarcinoma of the Right Colon in a Patient with Bloom Syndrome. Case Rep Surg 2016; 2016:3176842. [PMID: 27597923 PMCID: PMC5002463 DOI: 10.1155/2016/3176842] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Revised: 07/18/2016] [Accepted: 07/20/2016] [Indexed: 11/17/2022] Open
Abstract
Introduction. Bloom syndrome (BS) is an inherited disorder due to mutation in BLM gene. The diagnosis of BS should be considered in patients with growth retardation of prenatal onset, a photosensitive rash in a butterfly distribution over the cheeks, and an increased risk of cancer at an early age. Clinical manifestations also include short stature, dolichocephaly, prominent ears, micrognathia, malar hypoplasia and a high-pitched voice, immunodeficiency, type II diabetes, and hypogonadism associated with male infertility and female subfertility. The aim of this report is to describe case of patient with BS who developed adenocarcinoma of the cecum, successfully treated by right colectomy. Case Report. A 40-year-old man underwent colonoscopy to investigate the cause of his diarrhea, weight loss, and anemia. The patient knew that he was a carrier of BS diagnosed at young age. The colonoscopy showed an expansive and vegetating mass with 5.5 cm in diameter, located within the ascending colon. Histopathological analysis of tissue fragments collected during colonoscopy confirmed the presence of tubular adenocarcinoma, and he was referred for an oncological right colectomy. The procedure was performed without complications, and the patient was discharged on the fifth postoperative day. Histopathological examination of the surgical specimen confirmed the presence of a grade II tubular adenocarcinoma (stage IIA). The patient is currently well five years after surgery, without clinical or endoscopic signs of relapse in a multidisciplinary approach for the monitoring of comorbidities related to BS. Conclusion. Despite the development of colorectal cancer to be, a possibility rarely described the present case shows the need for early screening for colorectal cancer in all patients affected by BS.
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Nielsen AY, Gjerstorff MF. Ectopic Expression of Testis Germ Cell Proteins in Cancer and Its Potential Role in Genomic Instability. Int J Mol Sci 2016; 17:E890. [PMID: 27275820 PMCID: PMC4926424 DOI: 10.3390/ijms17060890] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2016] [Revised: 05/23/2016] [Accepted: 06/01/2016] [Indexed: 12/18/2022] Open
Abstract
Genomic instability is a hallmark of human cancer and an enabling factor for the genetic alterations that drive cancer development. The processes involved in genomic instability resemble those of meiosis, where genetic material is interchanged between homologous chromosomes. In most types of human cancer, epigenetic changes, including hypomethylation of gene promoters, lead to the ectopic expression of a large number of proteins normally restricted to the germ cells of the testis. Due to the similarities between meiosis and genomic instability, it has been proposed that activation of meiotic programs may drive genomic instability in cancer cells. Some germ cell proteins with ectopic expression in cancer cells indeed seem to promote genomic instability, while others reduce polyploidy and maintain mitotic fidelity. Furthermore, oncogenic germ cell proteins may indirectly contribute to genomic instability through induction of replication stress, similar to classic oncogenes. Thus, current evidence suggests that testis germ cell proteins are implicated in cancer development by regulating genomic instability during tumorigenesis, and these proteins therefore represent promising targets for novel therapeutic strategies.
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Affiliation(s)
- Aaraby Yoheswaran Nielsen
- Department of Cancer and Inflammation Research, Institute for Molecular Medicine, University of Southern Denmark, Odense DK-5000, Denmark.
| | - Morten Frier Gjerstorff
- Department of Cancer and Inflammation Research, Institute for Molecular Medicine, University of Southern Denmark, Odense DK-5000, Denmark.
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38
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Devlin R, Marques CA, Paape D, Prorocic M, Zurita-Leal AC, Campbell SJ, Lapsley C, Dickens N, McCulloch R. Mapping replication dynamics in Trypanosoma brucei reveals a link with telomere transcription and antigenic variation. eLife 2016; 5:e12765. [PMID: 27228154 PMCID: PMC4946898 DOI: 10.7554/elife.12765] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2015] [Accepted: 05/26/2016] [Indexed: 01/14/2023] Open
Abstract
Survival of Trypanosoma brucei depends upon switches in its protective Variant Surface Glycoprotein (VSG) coat by antigenic variation. VSG switching occurs by frequent homologous recombination, which is thought to require locus-specific initiation. Here, we show that a RecQ helicase, RECQ2, acts to repair DNA breaks, including in the telomeric site of VSG expression. Despite this, RECQ2 loss does not impair antigenic variation, but causes increased VSG switching by recombination, arguing against models for VSG switch initiation through direct generation of a DNA double strand break (DSB). Indeed, we show DSBs inefficiently direct recombination in the VSG expression site. By mapping genome replication dynamics, we reveal that the transcribed VSG expression site is the only telomeric site that is early replicating - a differential timing only seen in mammal-infective parasites. Specific association between VSG transcription and replication timing reveals a model for antigenic variation based on replication-derived DNA fragility.
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Affiliation(s)
- Rebecca Devlin
- The Wellcome Trust Centre for Molecular Parasitology, Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, United Kingdom
| | - Catarina A Marques
- The Wellcome Trust Centre for Molecular Parasitology, Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, United Kingdom
| | - Daniel Paape
- The Wellcome Trust Centre for Molecular Parasitology, Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, United Kingdom
| | - Marko Prorocic
- The Wellcome Trust Centre for Molecular Parasitology, Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, United Kingdom
| | - Andrea C Zurita-Leal
- The Wellcome Trust Centre for Molecular Parasitology, Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, United Kingdom
| | - Samantha J Campbell
- The Wellcome Trust Centre for Molecular Parasitology, Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, United Kingdom
| | - Craig Lapsley
- The Wellcome Trust Centre for Molecular Parasitology, Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, United Kingdom
| | - Nicholas Dickens
- The Wellcome Trust Centre for Molecular Parasitology, Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, United Kingdom
| | - Richard McCulloch
- The Wellcome Trust Centre for Molecular Parasitology, Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, United Kingdom
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Evangelisti C, Cenni V, Lattanzi G. Potential therapeutic effects of the MTOR inhibitors for preventing ageing and progeria-related disorders. Br J Clin Pharmacol 2016; 82:1229-1244. [PMID: 26952863 PMCID: PMC5061804 DOI: 10.1111/bcp.12928] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2015] [Revised: 03/02/2016] [Accepted: 03/02/2016] [Indexed: 12/25/2022] Open
Abstract
The mammalian target of rapamycin (mTOR) pathway is an highly conserved signal transduction axis involved in many cellular processes, such as cell growth, survival, transcription, translation, apoptosis, metabolism, motility and autophagy. Recently, this signalling pathway has come to the attention of the scientific community owing to the unexpected finding that inhibition of mTOR by rapamycin, an antibiotic with immunosuppressant and chemotherapeutic properties, extends lifespan in diverse animal models. Moreover, rapamycin has been reported to rescue the cellular phenotype in a progeroid syndrome [Hutchinson–Gilford Progeria syndrome (HGPS)] that recapitulates most of the traits of physiological ageing. The promising perspectives raised by these results warrant a better understanding of mTOR signalling and the potential applications of mTOR inhibitors to counteract ageing‐associated diseases and increase longevity. This review is focused on these issues.
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Affiliation(s)
- Camilla Evangelisti
- CNR Institute for Molecular Genetics, Unit of Bologna, Bologna, Italy.,Rizzoli Orthopedic Institute, Laboratory of Musculoskeletal Cell Biology, Bologna, Italy
| | - Vittoria Cenni
- CNR Institute for Molecular Genetics, Unit of Bologna, Bologna, Italy.,Rizzoli Orthopedic Institute, Laboratory of Musculoskeletal Cell Biology, Bologna, Italy
| | - Giovanna Lattanzi
- CNR Institute for Molecular Genetics, Unit of Bologna, Bologna, Italy. .,Rizzoli Orthopedic Institute, Laboratory of Musculoskeletal Cell Biology, Bologna, Italy.
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40
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Swahari V, Nakamura A. Speeding up the clock: The past, present and future of progeria. Dev Growth Differ 2015; 58:116-30. [DOI: 10.1111/dgd.12251] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Revised: 10/15/2015] [Accepted: 10/15/2015] [Indexed: 12/18/2022]
Affiliation(s)
- Vijay Swahari
- Neuroscience Center; University of North Carolina; Chapel Hill North Carolina USA
| | - Ayumi Nakamura
- Neuroscience Center; University of North Carolina; Chapel Hill North Carolina USA
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41
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Zins K, Frech B, Taubenschuss E, Schneeberger C, Abraham D, Schreiber M. Association of the rs1346044 Polymorphism of the Werner Syndrome Gene RECQL2 with Increased Risk and Premature Onset of Breast Cancer. Int J Mol Sci 2015; 16:29643-53. [PMID: 26690424 PMCID: PMC4691135 DOI: 10.3390/ijms161226192] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2015] [Revised: 11/27/2015] [Accepted: 12/03/2015] [Indexed: 12/20/2022] Open
Abstract
Like other RECQ helicases, WRN/RECQL2 plays a crucial role in DNA replication and the maintenance of genome stability. Inactivating mutations in RECQL2 lead to Werner syndrome, a rare autosomal disease associated with premature aging and an increased susceptibility to multiple cancer types. We analyzed the association of two coding single-nucleotide polymorphisms in WRN, Cys1367Arg (rs1346044), and Arg834Cys (rs3087425), with the risk, age at onset, and clinical subclasses of breast cancer in a hospital-based case-control study of an Austrian population of 272 breast cancer patients and 254 controls. Here we report that the rare homozygous CC genotype of rs1346044 was associated with an approximately two-fold elevated breast cancer risk. Moreover, patients with the CC genotype exhibited a significantly increased risk of developing breast cancer under the age of 55 in both recessive and log-additive genetic models. CC patients developed breast cancer at a mean age of 55.2 ± 13.3 years and TT patients at 60.2 ± 14.7 years. Consistently, the risk of breast cancer was increased in pre-menopausal patients in the recessive model. These findings suggest that the CC genotype of WRN rs1346044 may contribute to an increased risk and a premature onset of breast cancer.
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Affiliation(s)
- Karin Zins
- Laboratory for Molecular Cellular Biology, Center for Anatomy and Cell Biology, Medical University of Vienna, A-1090 Vienna, Austria.
| | - Barbara Frech
- Department of Obstetrics and Gynecology, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna, Austria.
| | - Eva Taubenschuss
- Department of Obstetrics and Gynecology, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna, Austria.
| | - Christian Schneeberger
- Department of Obstetrics and Gynecology, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna, Austria.
| | - Dietmar Abraham
- Laboratory for Molecular Cellular Biology, Center for Anatomy and Cell Biology, Medical University of Vienna, A-1090 Vienna, Austria.
- Comprehensive Cancer Center (CCC), Medical University of Vienna, A-1090 Vienna, Austria.
| | - Martin Schreiber
- Department of Obstetrics and Gynecology, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna, Austria.
- Comprehensive Cancer Center (CCC), Medical University of Vienna, A-1090 Vienna, Austria.
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42
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RECQL5 has unique strand annealing properties relative to the other human RecQ helicase proteins. DNA Repair (Amst) 2015; 37:53-66. [PMID: 26717024 DOI: 10.1016/j.dnarep.2015.11.005] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2015] [Revised: 11/21/2015] [Accepted: 11/24/2015] [Indexed: 11/24/2022]
Abstract
The RecQ helicases play important roles in genome maintenance and DNA metabolism (replication, recombination, repair, and transcription). Five different homologs are present in humans, three of which are implicated in accelerated aging genetic disorders: Rothmund Thomson (RECQL4), Werner (WRN), and Bloom (BLM) syndromes. While the DNA helicase activities of the 5 human RecQ helicases have been extensively characterized, much less is known about their DNA double strand annealing activities. Strand annealing is an important integral enzymatic activity in DNA metabolism, including DNA repair. Here, we have characterized the strand annealing activities of all five human RecQ helicase proteins and compared them. Interestingly, the relative strand annealing activities of the five RecQ proteins are not directly (inversely) related to their helicase activities. RECQL5 possesses relatively strong annealing activity on long or small duplexed substrates compared to the other RecQs. Additionally, the strand annealing activity of RECQL5 is not inhibited by the presence of ATP, unlike the other RecQs. We also show that RECQL5 efficiently catalyzes annealing of RNA to DNA in vitro in the presence or absence of ATP, revealing a possible new function for RECQL5. Additionally, we investigate how different known RecQ interacting proteins, RPA, Ku, FEN1 and RAD51, regulate their strand annealing activity. Collectively, we find that the human RecQ proteins possess differential DNA double strand annealing activities and we speculate on their individual roles in DNA repair. This insight is important in view of the many cellular DNA metabolic actions of the RecQ proteins and elucidates their unique functions in the cell.
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43
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Agrelo R, Sutz MA, Setien F, Aldunate F, Esteller M, Da Costa V, Achenbach R. A novel Werner Syndrome mutation: pharmacological treatment by read-through of nonsense mutations and epigenetic therapies. Epigenetics 2015; 10:329-41. [PMID: 25830902 DOI: 10.1080/15592294.2015.1027853] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Werner Syndrome (WS) is a rare inherited disease characterized by premature aging and increased propensity for cancer. Mutations in the WRN gene can be of several types, including nonsense mutations, leading to a truncated protein form. WRN is a RecQ family member with both helicase and exonuclease activities, and it participates in several cell metabolic pathways, including DNA replication, DNA repair, and telomere maintenance. Here, we reported a novel homozygous WS mutation (c.3767 C > G) in 2 Argentinian brothers, which resulted in a stop codon and a truncated protein (p.S1256X). We also observed increased WRN promoter methylation in the cells of patients and decreased messenger WRN RNA (WRN mRNA) expression. Finally, we showed that the read-through of nonsense mutation pharmacologic treatment with both aminoglycosides (AGs) and ataluren (PTC-124) in these cells restores full-length protein expression and WRN functionality.
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Affiliation(s)
- Ruben Agrelo
- a Epigenetics of Cancer and Aging Laboratory Institut Pasteur de Montevideo (IPMON) ; Montevideo , Uruguay
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44
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Mitotic phosphorylation of Bloom helicase at Thr182 is required for its proteasomal degradation and maintenance of chromosomal stability. Oncogene 2015; 35:1025-38. [DOI: 10.1038/onc.2015.157] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2014] [Revised: 03/15/2015] [Accepted: 03/30/2015] [Indexed: 12/12/2022]
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45
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Lu L, Harutyunyan K, Jin W, Wu J, Yang T, Chen Y, Joeng KS, Bae Y, Tao J, Dawson BC, Jiang MM, Lee B, Wang LL. RECQL4 Regulates p53 Function In Vivo During Skeletogenesis. J Bone Miner Res 2015; 30:1077-89. [PMID: 25556649 DOI: 10.1002/jbmr.2436] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/15/2014] [Revised: 11/30/2014] [Accepted: 12/12/2014] [Indexed: 11/05/2022]
Abstract
RECQ DNA helicases play critical roles in maintaining genomic stability, but their role in development has been less well studied. Rothmund-Thomson syndrome, RAPADILINO, and Baller-Gerold syndrome are rare genetic disorders caused by mutations in the RECQL4 gene. These patients have significant skeletal developmental abnormalities including radial ray, limb and craniofacial defects. To investigate the role of Recql4 in the developing skeletal system, we generated Recql4 conditional knockout mice targeting the skeletal lineage. Inactivation of Recql4 using the Prx1-Cre transgene led to limb abnormalities and craniosynostosis mimicking the major bone findings in human RECQL4 patients. These Prx1-Cre(+) ;Recql4(fl/fl) mice as well as Col2a1-Cre(+) ;Recql4(fl/fl) mice exhibited growth plate defects and an increased p53 response in affected tissues. Inactivation of Trp53 in these Recql4 mutants resulted in genetic rescue of the skeletal phenotypes, indicating an in vivo interaction between Recql4 and Trp53, and p53 activation as an underlying mechanism for the developmental bone abnormalities in RECQL4 disorders. Our findings show that RECQL4 is critical for skeletal development by modulating p53 activity in vivo.
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Affiliation(s)
- Linchao Lu
- Texas Children's Cancer Center, Department of Pediatrics, Houston, TX, USA
| | - Karine Harutyunyan
- Texas Children's Cancer Center, Department of Pediatrics, Houston, TX, USA
| | - Weidong Jin
- Texas Children's Cancer Center, Department of Pediatrics, Houston, TX, USA
| | - Jianhong Wu
- Texas Children's Cancer Center, Department of Pediatrics, Houston, TX, USA
| | - Tao Yang
- Center for Skeletal Diseases and Tumor Metastasis, Van Andel Research Institute, Grand Rapids, MI 49503, USA
| | - Yuqing Chen
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA.,Howard Hughes Medical Institute, Houston, TX, USA
| | - Kyu Sang Joeng
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - Yangjin Bae
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - Jianning Tao
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - Brian C Dawson
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA.,Howard Hughes Medical Institute, Houston, TX, USA
| | - Ming-Ming Jiang
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA.,Howard Hughes Medical Institute, Houston, TX, USA
| | - Brendan Lee
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA.,Howard Hughes Medical Institute, Houston, TX, USA
| | - Lisa L Wang
- Texas Children's Cancer Center, Department of Pediatrics, Houston, TX, USA
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46
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Monnat RJ. "...Rewritten in the skin": clues to skin biology and aging from inherited disease. J Invest Dermatol 2015; 135:1484-1490. [PMID: 25810110 PMCID: PMC4526269 DOI: 10.1038/jid.2015.88] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Revised: 02/07/2015] [Accepted: 02/24/2015] [Indexed: 12/11/2022]
Abstract
The growing diversity of heritable skin diseases, a practical challenge to clinicians and dermato-nosologists alike, has nonetheless served as a rich source of insight into skin biology and disease mechanisms. I summarize below some key insights from the recent gene-driven phase of research on Werner syndrome, a heritable adult progeroid syndrome with prominent dermatologic features, constitutional genomic instability, and an elevated risk of cancer. I also indicate how new insights into skin biology, disease, and aging may come from unexpected sources.
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Affiliation(s)
- Raymond J Monnat
- Department of Pathology and Genome Sciences, University of Washington, Seattle, Washington, USA.
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47
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Wu WQ, Hou XM, Li M, Dou SX, Xi XG. BLM unfolds G-quadruplexes in different structural environments through different mechanisms. Nucleic Acids Res 2015; 43:4614-26. [PMID: 25897130 PMCID: PMC4482088 DOI: 10.1093/nar/gkv361] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2015] [Revised: 04/06/2015] [Accepted: 04/07/2015] [Indexed: 11/30/2022] Open
Abstract
Mutations in the RecQ DNA helicase gene BLM give rise to Bloom's syndrome, which is a rare autosomal recessive disorder characterized by genetic instability and cancer predisposition. BLM helicase is highly active in binding and unwinding G-quadruplexes (G4s), which are physiological targets for BLM, as revealed by genome-wide characterizations of gene expression of cells from BS patients. With smFRET assays, we studied the molecular mechanism of BLM-catalyzed G4 unfolding and showed that ATP is required for G4 unfolding. Surprisingly, depending on the molecular environments of G4, BLM unfolds G4 through different mechanisms: unfolding G4 harboring a 3'-ssDNA tail in three discrete steps with unidirectional translocation, and unfolding G4 connected to dsDNA by ssDNA in a repetitive manner in which BLM remains anchored at the ss/dsDNA junction, and G4 was unfolded by reeling in ssDNA. This indicates that one BLM molecule may unfold G4s in different molecular environments through different mechanisms.
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Affiliation(s)
- Wen-Qiang Wu
- College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Xi-Miao Hou
- College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Ming Li
- Beijing National Laboratory for Condensed Matter Physics and CAS Key Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Shuo-Xing Dou
- Beijing National Laboratory for Condensed Matter Physics and CAS Key Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Xu-Guang Xi
- College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, China Laboratoire de Biologie et Pharmacologie Appliquée, Ecole Normale Supérieure de Cachan, Centre National de la Recherche Scientifique, 61 Avenue du Président Wilson, 94235 Cachan, France
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48
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Budhathoki JB, Stafford EJ, Yodh JG, Balci H. ATP-dependent G-quadruplex unfolding by Bloom helicase exhibits low processivity. Nucleic Acids Res 2015; 43:5961-70. [PMID: 25990739 PMCID: PMC4499149 DOI: 10.1093/nar/gkv531] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2015] [Accepted: 05/08/2015] [Indexed: 01/12/2023] Open
Abstract
Various helicases and single stranded DNA (ssDNA) binding proteins unfold G-quadruplex (GQ) structures. However, the underlying mechanisms of this activity have only recently come to focus. We report kinetic studies on Bloom (BLM) helicase and human telomeric GQ interactions using single-molecule Förster resonance energy transfer (smFRET). Using partial duplex DNA (pdDNA) constructs with different 5' ssDNA overhangs, we show that BLM localizes in the vicinity of ssDNA/double-stranded DNA (dsDNA) junction and reels in the ssDNA overhang in an ATP-dependent manner. A comparison of DNA constructs with or without GQ in the overhang shows that GQ unfolding is achieved in 50-70% of reeling attempts under physiological salt and pH conditions. The unsuccessful attempts often result in dissociation of BLM from DNA which slows down the overall BLM activity. BLM-mediated GQ unfolding is typically followed by refolding of the GQ, a pattern that is repeated several times before BLM dissociates from DNA. BLM is significantly less processive compared to the highly efficient GQ destabilizer Pif1 that can repeat GQ unfolding activity hundreds of times before dissociating from DNA. Despite the variations in processivity, our studies point to possible common patterns used by different helicases in minimizing the duration of stable GQ formation.
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Affiliation(s)
| | | | - Jaya G Yodh
- Department of Physics and Center for the Physics of Living Cells, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Hamza Balci
- Department of Physics, Kent State University, Kent, OH 44242, USA
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Wang S, Qin W, Li JH, Lu Y, Lu KY, Nong DG, Dou SX, Xu CH, Xi XG, Li M. Unwinding forward and sliding back: an intermittent unwinding mode of the BLM helicase. Nucleic Acids Res 2015; 43:3736-46. [PMID: 25765643 PMCID: PMC4402530 DOI: 10.1093/nar/gkv209] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2014] [Accepted: 03/02/2015] [Indexed: 01/11/2023] Open
Abstract
There are lines of evidence that the Bloom syndrome helicase, BLM, catalyzes regression of stalled replication forks and disrupts displacement loops (D-loops) formed during homologous recombination (HR). Here we constructed a forked DNA with a 3′ single-stranded gap and a 5′ double-stranded handle to partly mimic a stalled DNA fork and used magnetic tweezers to study BLM-catalyzed unwinding of the forked DNA. We have directly observed that the BLM helicase may slide on the opposite strand for some distance after duplex unwinding at different forces. For DNA construct with a long hairpin, progressive unwinding of the hairpin is frequently interrupted by strand switching and backward sliding of the enzyme. Quantitative study of the uninterrupted unwinding length (time) has revealed a two-state-transition mechanism for strand-switching during the unwinding process. Mutational studies revealed that the RQC domain plays an important role in stabilizing the helicase/DNA interaction during both DNA unwinding and backward sliding of BLM. Especially, Lys1125 in the RQC domain, a highly conserved amino acid among RecQ helicases, may be involved in the backward sliding activity. We have also directly observed the in vitro pathway that BLM disrupts the mimic stalled replication fork. These results may shed new light on the mechanisms for BLM in DNA repair and homologous recombination.
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Affiliation(s)
- Shuang Wang
- Beijing National Laboratory for Condensed Matter Physics and CAS Key Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Wei Qin
- College of Life Science and Technology, Northwest A & F University, Yangling, Shaanxi 712100, China
| | - Jing-Hua Li
- Beijing National Laboratory for Condensed Matter Physics and CAS Key Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Ying Lu
- Beijing National Laboratory for Condensed Matter Physics and CAS Key Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Ke-Yu Lu
- College of Life Science and Technology, Northwest A & F University, Yangling, Shaanxi 712100, China
| | - Da-Guan Nong
- Beijing National Laboratory for Condensed Matter Physics and CAS Key Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Shuo-Xing Dou
- Beijing National Laboratory for Condensed Matter Physics and CAS Key Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Chun-Hua Xu
- Beijing National Laboratory for Condensed Matter Physics and CAS Key Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Xu-Guang Xi
- College of Life Science and Technology, Northwest A & F University, Yangling, Shaanxi 712100, China Laboratoire de Biologie et PharmacologieAppliquée, Ecole Normale Supérieure de Cachan, Centre National de la Recherche Scientifique, 61 Avenue du Président Wilson, 94235 Cachan, France
| | - Ming Li
- Beijing National Laboratory for Condensed Matter Physics and CAS Key Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
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Chayka O, D'Acunto CW, Middleton O, Arab M, Sala A. Identification and pharmacological inactivation of the MYCN gene network as a therapeutic strategy for neuroblastic tumor cells. J Biol Chem 2014; 290:2198-212. [PMID: 25477524 PMCID: PMC4303671 DOI: 10.1074/jbc.m114.624056] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
The MYC family of transcription factors consists of three well characterized members, c-MYC, L-MYC, and MYCN, deregulated in the majority of human cancers. In neuronal tumors such as neuroblastoma, MYCN is frequently activated by gene amplification, and reducing its expression by RNA interference has been shown to promote growth arrest and apoptosis of tumor cells. From a clinical perspective, RNA interference is not yet a viable option, and small molecule inhibitors of transcription factors are difficult to develop. We therefore planned to identify, at the global level, the genes interacting functionally with MYCN required to promote fitness of tumor cells facing oncogenic stress. To find genes whose inactivation is synthetically lethal to MYCN, we implemented a genome-wide approach in which we carried out a drop-out shRNA screen using a whole genome library that was delivered into isogenic neuroblastoma cell lines expressing or not expressing MYCN. After the screen, we selected for in-depth analysis four shRNAs targeting AHCY, BLM, PKMYT1, and CKS1B. These genes were chosen because they are directly regulated by MYC proteins, associated with poor prognosis of neuroblastoma patients, and inhibited by small molecule compounds. Mechanistically, we found that BLM and PKMYT1 are required to limit oncogenic stress and promote stabilization of the MYCN protein. Cocktails of small molecule inhibitors of CKS1B, AHCY, BLM, and PKMYT1 profoundly affected the growth of all neuroblastoma cell lines but selectively caused death of MYCN-amplified cells. Our findings suggest that drugging the MYCN network is a promising avenue for the treatment of high risk, neuroblastic cancers.
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Affiliation(s)
- Olesya Chayka
- From the Brunel Institute of Cancer Genetics and Pharmacogenomics, Brunel University London, London UB8 3PH, United Kingdom and the Institute of Child Health, University College London, London WC1N 1EH, United Kingdom
| | - Cosimo Walter D'Acunto
- the Institute of Child Health, University College London, London WC1N 1EH, United Kingdom
| | - Odette Middleton
- the Institute of Child Health, University College London, London WC1N 1EH, United Kingdom
| | - Maryam Arab
- From the Brunel Institute of Cancer Genetics and Pharmacogenomics, Brunel University London, London UB8 3PH, United Kingdom and
| | - Arturo Sala
- From the Brunel Institute of Cancer Genetics and Pharmacogenomics, Brunel University London, London UB8 3PH, United Kingdom and the Institute of Child Health, University College London, London WC1N 1EH, United Kingdom
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