1
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Fraser B, Wilkins A, Whiting S, Liang M, Rebourcet D, Nixon B, Aitken RJ. Development of peptides for targeting cell ablation agents concurrently to the Sertoli and Leydig cell populations of the testes: An approach to non-surgical sterilization. PLoS One 2024; 19:e0292198. [PMID: 38574116 PMCID: PMC10994420 DOI: 10.1371/journal.pone.0292198] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Accepted: 12/28/2023] [Indexed: 04/06/2024] Open
Abstract
The surgical sterilization of cats and dogs has been used to prevent their unwanted breeding for decades. However, this is an expensive and invasive procedure, and often impractical in wider contexts, for example the control of feral populations. A sterilization agent that could be administered in a single injection, would not only eliminate the risks imposed by surgery but also be a much more cost-effective solution to this worldwide problem. In this study, we sought to develop a targeting peptide that would selectively bind to Leydig cells of the testes. Subsequently, after covalently attaching a cell ablation agent, Auristatin, to this peptide we aimed to apply this conjugated product (LH2Auristatin) to adult male mice in vivo, both alone and together with a previously developed Sertoli cell targeting peptide (FSH2Menadione). The application of LH2Auristatin alone resulted in an increase in sperm DNA damage, reduced mean testes weights and mean seminiferous tubule size, along with extensive germ cell apoptosis and a reduction in litter sizes. Together with FSH2Menadione there was also an increase in embryo resorptions. These promising results were observed in around a third of all treated animals. Given this variability, we discuss how these reagents might be modified in order to increase target cell ablation and improve their efficacy as sterilization agents.
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Affiliation(s)
- Barbara Fraser
- Priority Research Centre for Reproductive Science, University of Newcastle, Callaghan, NSW, Australia
- Pregnancy and Reproduction Program, Hunter Medical Research Institute, New Lambton Heights, NSW, Australia
- College of Engineering, Science and Environment, University of Newcastle, Callaghan, NSW, Australia
| | - Alex Wilkins
- Priority Research Centre for Reproductive Science, University of Newcastle, Callaghan, NSW, Australia
- Pregnancy and Reproduction Program, Hunter Medical Research Institute, New Lambton Heights, NSW, Australia
- College of Engineering, Science and Environment, University of Newcastle, Callaghan, NSW, Australia
| | - Sara Whiting
- Priority Research Centre for Reproductive Science, University of Newcastle, Callaghan, NSW, Australia
- Pregnancy and Reproduction Program, Hunter Medical Research Institute, New Lambton Heights, NSW, Australia
- College of Engineering, Science and Environment, University of Newcastle, Callaghan, NSW, Australia
| | - Mingtao Liang
- School of Biomedical Sciences and Pharmacy, University of Newcastle, Callaghan, NSW, Australia
- College of Health, Medicine and Wellbeing, University of Newcastle, Callaghan, NSW, Australia
| | - Diane Rebourcet
- Priority Research Centre for Reproductive Science, University of Newcastle, Callaghan, NSW, Australia
- Pregnancy and Reproduction Program, Hunter Medical Research Institute, New Lambton Heights, NSW, Australia
- College of Engineering, Science and Environment, University of Newcastle, Callaghan, NSW, Australia
| | - Brett Nixon
- Priority Research Centre for Reproductive Science, University of Newcastle, Callaghan, NSW, Australia
- Pregnancy and Reproduction Program, Hunter Medical Research Institute, New Lambton Heights, NSW, Australia
- College of Engineering, Science and Environment, University of Newcastle, Callaghan, NSW, Australia
| | - Robert John Aitken
- Priority Research Centre for Reproductive Science, University of Newcastle, Callaghan, NSW, Australia
- Pregnancy and Reproduction Program, Hunter Medical Research Institute, New Lambton Heights, NSW, Australia
- College of Engineering, Science and Environment, University of Newcastle, Callaghan, NSW, Australia
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2
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Giorgio M, Dellino GI, Gambino V, Roda N, Pelicci PG. On the epigenetic role of guanosine oxidation. Redox Biol 2020; 29:101398. [PMID: 31926624 PMCID: PMC6926346 DOI: 10.1016/j.redox.2019.101398] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Revised: 11/23/2019] [Accepted: 12/02/2019] [Indexed: 01/14/2023] Open
Abstract
Chemical modifications of DNA and RNA regulate genome functions or trigger mutagenesis resulting in aging or cancer. Oxidations of macromolecules, including DNA, are common reactions in biological systems and often part of regulatory circuits rather than accidental events. DNA alterations are particularly relevant since the unique role of nuclear and mitochondrial genome is coding enduring and inheritable information. Therefore, an alteration in DNA may represent a relevant problem given its transmission to daughter cells. At the same time, the regulation of gene expression allows cells to continuously adapt to the environmental changes that occur throughout the life of the organism to ultimately maintain cellular homeostasis. Here we review the multiple ways that lead to DNA oxidation and the regulation of mechanisms activated by cells to repair this damage. Moreover, we present the recent evidence suggesting that DNA damage caused by physiological metabolism acts as epigenetic signal for regulation of gene expression. In particular, the predisposition of guanine to oxidation might reflect an adaptation to improve the genome plasticity to redox changes.
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Affiliation(s)
- Marco Giorgio
- Department of Experimental Oncology, European Institute of Oncology-IRCCS, Via Adamello 16, 20139, Milano, Italy; Department of Biomedical Sciences, University of Padova, Via Ugo Bassi 58/B, 35131, Padova, Italy.
| | - Gaetano Ivan Dellino
- Department of Experimental Oncology, European Institute of Oncology-IRCCS, Via Adamello 16, 20139, Milano, Italy; Department of Oncology and Hemato-Oncology, University of Milan, Milan, Italy
| | - Valentina Gambino
- Department of Experimental Oncology, European Institute of Oncology-IRCCS, Via Adamello 16, 20139, Milano, Italy
| | - Niccolo' Roda
- Department of Experimental Oncology, European Institute of Oncology-IRCCS, Via Adamello 16, 20139, Milano, Italy
| | - Pier Giuseppe Pelicci
- Department of Experimental Oncology, European Institute of Oncology-IRCCS, Via Adamello 16, 20139, Milano, Italy; Department of Oncology and Hemato-Oncology, University of Milan, Milan, Italy
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3
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Endutkin AV, Yudkina AV, Sidorenko VS, Zharkov DO. Transient protein-protein complexes in base excision repair. J Biomol Struct Dyn 2018; 37:4407-4418. [PMID: 30488779 DOI: 10.1080/07391102.2018.1553741] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Transient protein-protein complexes are of great importance for organizing multiple enzymatic reactions into productive reaction pathways. Base excision repair (BER), a process of critical importance for maintaining genome stability against a plethora of DNA-damaging factors, involves several enzymes, including DNA glycosylases, AP endonucleases, DNA polymerases, DNA ligases and accessory proteins acting sequentially on the same damaged site in DNA. Rather than being assembled into one stable multisubunit complex, these enzymes pass the repair intermediates between them in a highly coordinated manner. In this review, we discuss the nature and the role of transient complexes arising during BER as deduced from structural and kinetic data. Almost all of the transient complexes are DNA-mediated, although some may also exist in solution and strengthen under specific conditions. The best-studied example, the interactions between DNA glycosylases and AP endonucleases, is discussed in more detail to provide a framework for distinguishing between stable and transient complexes based on the kinetic data. Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Anton V Endutkin
- SB RAS Institute of Chemical Biology and Fundamental Medicine , Novosibirsk , Russia.,Novosibirsk State University , Novosibirsk , Russia.,Podalirius Ltd. , Novosibirsk , Russia
| | - Anna V Yudkina
- SB RAS Institute of Chemical Biology and Fundamental Medicine , Novosibirsk , Russia.,Novosibirsk State University , Novosibirsk , Russia
| | - Viktoriya S Sidorenko
- Department of Pharmacological Sciences, Stony Brook University , Stony Brook , NY , USA
| | - Dmitry O Zharkov
- SB RAS Institute of Chemical Biology and Fundamental Medicine , Novosibirsk , Russia.,Novosibirsk State University , Novosibirsk , Russia
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4
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Bauer NC, Corbett AH, Doetsch PW. The current state of eukaryotic DNA base damage and repair. Nucleic Acids Res 2015; 43:10083-101. [PMID: 26519467 PMCID: PMC4666366 DOI: 10.1093/nar/gkv1136] [Citation(s) in RCA: 104] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Accepted: 10/16/2015] [Indexed: 12/15/2022] Open
Abstract
DNA damage is a natural hazard of life. The most common DNA lesions are base, sugar, and single-strand break damage resulting from oxidation, alkylation, deamination, and spontaneous hydrolysis. If left unrepaired, such lesions can become fixed in the genome as permanent mutations. Thus, evolution has led to the creation of several highly conserved, partially redundant pathways to repair or mitigate the effects of DNA base damage. The biochemical mechanisms of these pathways have been well characterized and the impact of this work was recently highlighted by the selection of Tomas Lindahl, Aziz Sancar and Paul Modrich as the recipients of the 2015 Nobel Prize in Chemistry for their seminal work in defining DNA repair pathways. However, how these repair pathways are regulated and interconnected is still being elucidated. This review focuses on the classical base excision repair and strand incision pathways in eukaryotes, considering both Saccharomyces cerevisiae and humans, and extends to some important questions and challenges facing the field of DNA base damage repair.
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Affiliation(s)
- Nicholas C Bauer
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA 30322, USA Graduate Program in Biochemistry, Cell, and Developmental Biology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Anita H Corbett
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA 30322, USA Winship Cancer Institute, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Paul W Doetsch
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA 30322, USA Winship Cancer Institute, Emory University School of Medicine, Atlanta, GA 30322, USA Department of Radiation Oncology, Emory University School of Medicine, Atlanta, GA 30322, USA Department of Hematology and Medical Oncology, Emory University School of Medicine, Atlanta, GA 30322, USA
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5
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Sampath H. Oxidative DNA damage in disease--insights gained from base excision repair glycosylase-deficient mouse models. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2014; 55:689-703. [PMID: 25044514 DOI: 10.1002/em.21886] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2014] [Accepted: 06/24/2014] [Indexed: 05/10/2023]
Abstract
Cellular components, including nucleic acids, are subject to oxidative damage. If left unrepaired, this damage can lead to multiple adverse cellular outcomes, including increased mutagenesis and cell death. The major pathway for repair of oxidative base lesions is the base excision repair pathway, catalyzed by DNA glycosylases with overlapping but distinct substrate specificities. To understand the role of these glycosylases in the initiation and progression of disease, several transgenic mouse models have been generated to carry a targeted deletion or overexpression of one or more glycosylases. This review summarizes some of the major findings from transgenic animal models of altered DNA glycosylase expression, especially as they relate to pathologies ranging from metabolic disease and cancer to inflammation and neuronal health.
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Affiliation(s)
- Harini Sampath
- Oregon Institute of Occupational Health Sciences, Oregon Health & Science University, Portland, Oregon
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6
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Luo J, Hosoki K, Bacsi A, Radak Z, Hegde ML, Sur S, Hazra TK, Brasier AR, Ba X, Boldogh I. 8-Oxoguanine DNA glycosylase-1-mediated DNA repair is associated with Rho GTPase activation and α-smooth muscle actin polymerization. Free Radic Biol Med 2014; 73:430-8. [PMID: 24681335 PMCID: PMC4156873 DOI: 10.1016/j.freeradbiomed.2014.03.030] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/04/2014] [Revised: 03/12/2014] [Accepted: 03/19/2014] [Indexed: 12/01/2022]
Abstract
Reactive oxygen species (ROS) are activators of cell signaling and modify cellular molecules, including DNA. 8-Oxo-7,8-dihydroguanine (8-oxoG) is one of the prominent lesions in oxidatively damaged DNA, whose accumulation is causally linked to various diseases and aging processes, whereas its etiological relevance is unclear. 8-OxoG is repaired by the 8-oxoguanine DNA glycosylase-1 (OGG1)-initiated DNA base excision repair (BER) pathway. OGG1 binds free 8-oxoG and this complex functions as an activator of Ras family GTPases. Here we examined whether OGG1-initiated BER is associated with the activation of Rho GTPase and mediates changes in the cytoskeleton. To test this possibility, we induced OGG1-initiated BER in cultured cells and mouse lungs and used molecular approaches such as active Rho pull-down assays, siRNA ablation of gene expression, immune blotting, and microscopic imaging. We found that OGG1 physically interacts with Rho GTPase and, in the presence of 8-oxoG base, increases Rho-GTP levels in cultured cells and lungs, which mediates α-smooth muscle actin (α-SMA) polymerization into stress fibers and increases the level of α-SMA in insoluble cellular/tissue fractions. These changes were absent in cells lacking OGG1. These unexpected data and those showing that 8-oxoG repair is a lifetime process suggest that, via Rho GTPase, OGG1 could be involved in the cytoskeletal changes and organ remodeling observed in various chronic diseases.
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Affiliation(s)
- Jixian Luo
- Department of Microbiology and Immunology, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA
| | - Koa Hosoki
- Department of Internal Medicine, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA
| | - Attila Bacsi
- Department of Microbiology and Immunology, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA
| | - Zsolt Radak
- Department of Microbiology and Immunology, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA
| | - Muralidhar L Hegde
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA
| | - Sanjiv Sur
- Department of Internal Medicine, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA; Sealy Center for Molecular Medicine, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA
| | - Tapas K Hazra
- Department of Internal Medicine, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA; Sealy Center for Molecular Medicine, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA
| | - Allan R Brasier
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA; Sealy Center for Molecular Medicine, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA
| | - Xueqing Ba
- Department of Microbiology and Immunology, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA
| | - Istvan Boldogh
- Department of Microbiology and Immunology, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA; Sealy Center for Molecular Medicine, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA.
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7
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Hajas G, Bacsi A, Aguilera-Aguirre L, Hegde ML, Tapas KH, Sur S, Radak Z, Ba X, Boldogh I. 8-Oxoguanine DNA glycosylase-1 links DNA repair to cellular signaling via the activation of the small GTPase Rac1. Free Radic Biol Med 2013; 61:384-94. [PMID: 23612479 PMCID: PMC3795866 DOI: 10.1016/j.freeradbiomed.2013.04.011] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/28/2012] [Revised: 02/24/2013] [Accepted: 04/09/2013] [Indexed: 12/20/2022]
Abstract
8-Oxo-7,8-dihydroguanine (8-oxoG) is one of the most abundant DNA base lesions induced by reactive oxygen species (ROS). Accumulation of 8-oxoG in the mammalian genome is considered a marker of oxidative stress, to be causally linked to inflammation, and is thought to contribute to aging processes and various aging-related diseases. Unexpectedly, mice that lack 8-oxoguanine DNA glycosylase-1 (OGG1) activity and accumulate 8-oxoG in their genome have a normal phenotype and longevity; in fact, they show increased resistance to both inflammation and oxidative stress. OGG1 excises and generates free 8-oxoG base during DNA base-excision repair (BER) processes. In the present study, we report that in the presence of the 8-oxoG base, OGG1 physically interacts with guanine nucleotide-free and GDP-bound Rac1 protein. This interaction results in rapid GDP→GTP, but not GTP→GDP, exchange in vitro. Importantly, a rise in the intracellular 8-oxoG base levels increases the proportion of GTP-bound Rac1. In turn Rac1-GTP mediates an increase in ROS levels via nuclear membrane-associated NADPH oxidase type 4. These results show a novel mechanism by which OGG1 in complex with 8-oxoG is linked to redox signaling and cellular responses.
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Affiliation(s)
- Gyorgy Hajas
- Department of Microbiology and Immunology, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA
| | - Attila Bacsi
- Department of Microbiology and Immunology, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA
| | - Leopoldo Aguilera-Aguirre
- Department of Microbiology and Immunology, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA
| | - Muralidhar L Hegde
- Department of Biochemistry & Molecular Biology, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA
| | - K Hazra Tapas
- Department of Internal Medicine, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA; Sealy Center for Molecular Medicine, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA; Department of Biochemistry & Molecular Biology, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA
| | - Sanjiv Sur
- Department of Internal Medicine, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA; Sealy Center for Molecular Medicine, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA
| | - Zsolt Radak
- Department of Microbiology and Immunology, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA
| | - Xueqing Ba
- Department of Microbiology and Immunology, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA
| | - Istvan Boldogh
- Department of Microbiology and Immunology, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA; Sealy Center for Molecular Medicine, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA.
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8
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German P, Szaniszlo P, Hajas G, Radak Z, Bacsi A, Hazra TK, Hegde ML, Ba X, Boldogh I. Activation of cellular signaling by 8-oxoguanine DNA glycosylase-1-initiated DNA base excision repair. DNA Repair (Amst) 2013; 12:856-63. [PMID: 23890570 DOI: 10.1016/j.dnarep.2013.06.006] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2013] [Revised: 06/29/2013] [Accepted: 06/30/2013] [Indexed: 01/16/2023]
Abstract
Accumulation of 8-oxo-7,8-dihydroguanine (8-oxoG) in the DNA results in genetic instability and mutagenesis, and is believed to contribute to carcinogenesis, aging processes and various aging-related diseases. 8-OxoG is removed from the DNA via DNA base excision repair (BER), initiated by 8-oxoguanine DNA glycosylase-1 (OGG1). Our recent studies have shown that OGG1 binds its repair product 8-oxoG base with high affinity at a site independent from its DNA lesion-recognizing catalytic site and the OGG1•8-oxoG complex physically interacts with canonical Ras family members. Furthermore, exogenously added 8-oxoG base enters the cells and activates Ras GTPases; however, a link has not yet been established between cell signaling and DNA BER, which is the endogenous source of the 8-oxoG base. In this study, we utilized KG-1 cells expressing a temperature-sensitive mutant OGG1, siRNA ablation of gene expression, and a variety of molecular biological assays to define a link between OGG1-BER and cellular signaling. The results show that due to activation of OGG1-BER, 8-oxoG base is released from the genome in sufficient quantities for activation of Ras GTPase and resulting in phosphorylation of the downstream Ras targets Raf1, MEK1,2 and ERK1,2. These results demonstrate a previously unrecognized mechanism for cellular responses to OGG1-initiated DNA BER.
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Affiliation(s)
- Peter German
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX 77555, USA
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9
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Sampath H, McCullough AK, Lloyd RS. Regulation of DNA glycosylases and their role in limiting disease. Free Radic Res 2012; 46:460-78. [PMID: 22300253 DOI: 10.3109/10715762.2012.655730] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
This review will present a current understanding of mechanisms for the initiation of base excision repair (BER) of oxidatively-induced DNA damage and the biological consequences of deficiencies in these enzymes in mouse model systems and human populations.
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Affiliation(s)
- Harini Sampath
- Center for Research on Occupational and Environmental Toxicology, Oregon Health & Science University, 3181 SW Sam Jackson Park Rd, Portland, Oregon 97239 - 3098, USA
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10
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Hubert T, Vandekerckhove J, Gettemans J. Cdk1 and BRCA1 target γ-tubulin to microtubule domains. Biochem Biophys Res Commun 2011; 414:240-5. [PMID: 21951856 DOI: 10.1016/j.bbrc.2011.09.064] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2011] [Accepted: 09/13/2011] [Indexed: 01/01/2023]
Abstract
DNA damage is a critical event that requires an appropriate cellular response. This is mediated by checkpoint proteins such as Cdk1 that controls S/G2 and G2/M transition. Cdk1 is required for BRCA1 transport to DNA damage sites inside the nucleus where BRCA1 functions as a scaffold to initiate a signaling cascade. BRCA1 is a multifunctional protein that also ubiquitinates γ-tubulin and, consequently, inhibits microtubule nucleation at the centrosome. Here, we report that γ-tubulin also localizes at confined areas in the microtubule network. Nocodazole-mediated microtubule depolymeration results in disappearance of this γ-tubulin fraction, while microtubule stabilization by taxol preserves this structure. Surprisingly, overexpression of Cdk1 or BRCA1 greatly expands the γ-tubulin coating of microtubules, suggesting that the microtubule-bound γ-tubulin is involved in DNA damage response. This is in accordance with numerous reports of microtubule-associated DNA damage proteins, such as p53, that are transported to the nucleus when DNA damage occurs. γ-Tubulin itself has been reported to form complexes with DNA repair proteins in the nucleus.
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Affiliation(s)
- Thomas Hubert
- Department of Medical Protein Research, VIB, B-9000 Ghent, Belgium
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11
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Gildemeister OS, Sage JM, Knight KL. Cellular redistribution of Rad51 in response to DNA damage: novel role for Rad51C. J Biol Chem 2009; 284:31945-52. [PMID: 19783859 DOI: 10.1074/jbc.m109.024646] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Exposure of cells to DNA-damaging agents results in a rapid increase in the formation of subnuclear complexes containing Rad51. To date, it has not been determined to what extent DNA damage-induced cytoplasmic to nuclear transport of Rad51 may contribute to this process. We have analyzed subcellular fractions of HeLa and HCT116 cells and found a significant increase in nuclear Rad51 levels following exposure to a modest dose of ionizing radiation (2 grays). We also observed a DNA damage-induced increase in nuclear Rad51 in the Brca2-defective cell line Capan-1. To address a possible Brca2-independent mechanism for Rad51 nuclear transport, we analyzed subcellular fractions for two other Rad51-interacting proteins, Rad51C and Xrcc3. Rad51C has a functional nuclear localization signal, and although we found that the subcellular distribution of Xrcc3 was not significantly affected by DNA damage, there was a damage-induced increase in nuclear Rad51C. Furthermore, RNA interference-mediated depletion of Rad51C in HeLa and Capan-1 cells resulted in lower steady-state levels of nuclear Rad51 as well as a diminished DNA damage-induced increase. Our results provide important insight into the cellular regulation of Rad51 nuclear entry and a role for Rad51C in this process.
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Affiliation(s)
- Otto S Gildemeister
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, Massachusetts 01605, USA
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12
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Gonzalez L, Lison D, Kirsch-Volders M. Genotoxicity of engineered nanomaterials: A critical review. Nanotoxicology 2009. [DOI: 10.1080/17435390802464986] [Citation(s) in RCA: 121] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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13
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Deshpande GP, Hayles J, Hoe KL, Kim DU, Park HO, Hartsuiker E. Screening a genome-wide S. pombe deletion library identifies novel genes and pathways involved in genome stability maintenance. DNA Repair (Amst) 2009; 8:672-9. [PMID: 19264558 DOI: 10.1016/j.dnarep.2009.01.016] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2008] [Revised: 01/19/2009] [Accepted: 01/20/2009] [Indexed: 11/27/2022]
Abstract
The maintenance of genome stability is essential for an organism to avoid cell death and cancer. Based on screens for mutant sensitivity against DNA damaging agents a large number of DNA repair and DNA damage checkpoint genes have previously been identified in genetically amenable model organisms. These screens have however not been exhaustive and various genes have been, and remain to be, identified by other means. We therefore screened a genome-wide Schizosaccharomyces pombe deletion library for mutants sensitive against various DNA damaging agents. Screening the library on different concentrations of these genotoxins allowed us to assign a semi-quantitative score to each mutant expressing the degree of sensitivity. We isolated a total of 229 mutants which show sensitivity to one or more of the DNA damaging agents used. This set of mutants was significantly enriched for processes involved in DNA replication, DNA repair, DNA damage checkpoint, response to UV, mating type switching, telomere length maintenance and meiosis, and also for processes involved in the establishment and maintenance of chromatin architecture (notably members of the SAGA complex), transcription (members of the CCR4-Not complex) and microtubule related processes (members of the DASH complex). We also identified 23 sensitive mutants which had previously been classified as "sequence orphan" or as "conserved hypothetical". Among these, we identified genes showing extensive homology to CtIP, Stra13, Ybp1/Ybp2, Human Fragile X mental retardation interacting protein NUFIP1, and Aprataxin. The identification of these homologues will provide a basis for the further characterisation of the role of these conserved proteins in the genetically amenable model organism S. pombe.
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Affiliation(s)
- Gaurang P Deshpande
- Genome Damage and Stability Centre, University of Sussex, Brighton BN1 9RQ, UK
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14
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Chaudhry MA. Base excision repair of ionizing radiation-induced DNA damage in G1 and G2 cell cycle phases. Cancer Cell Int 2007; 7:15. [PMID: 17892593 PMCID: PMC2063494 DOI: 10.1186/1475-2867-7-15] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2007] [Accepted: 09/24/2007] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Major genomic surveillance mechanisms regulated in response to DNA damage exist at the G1/S and G2/M checkpoints. It is presumed that these delays provide time for the repair of damaged DNA. Cells have developed multiple DNA repair pathways to protect themselves from different types of DNA damage. Oxidative DNA damage is processed by the base excision repair (BER) pathway. Little is known about the BER of ionizing radiation-induced DNA damage and putative heterogeneity of BER in the cell cycle context. We measured the activities of three BER enzymes throughout the cell cycle to investigate the cell cycle-specific repair of ionizing radiation-induced DNA damage. We further examined BER activities in G2 arrested human cells after exposure to ionizing radiation. RESULTS Using an in vitro incision assay involving radiolabeled oligonucleotides with specific DNA lesions, we examined the activities of several BER enzymes in the whole cell extracts prepared from synchronized human HeLa cells irradiated in G1 and G2 phase of the cell cycle. The activities of human endonuclease III (hNTH1), a glycosylase/lyase that removes several damaged bases from DNA including dihydrouracil (DHU), 8-oxoguanine-DNA glycosylase (hOGG1) that recognizes 7,8-dihydro-8-oxo-2'-deoxyguanosine (8-oxoG) lesion and apurinic/apyrimidinic endonuclease (hAPE1) that acts on abasic sites including synthetic analog furan were examined. CONCLUSION Overall the repair activities of hNTH1 and hAPE1 were higher in the G1 compared to G2 phase of the cell cycle. The percent cleavages of oligonucleotide substrate with furan were greater than substrate with DHU in both G1 and G2 phases. The irradiation of cells enhanced the cleavage of substrates with furan and DHU only in G1 phase. The activity of hOGG1 was much lower and did not vary within the cell cycle. These results demonstrate the cell cycle phase dependence on the BER of ionizing radiation-induced DNA damage. Interestingly no evidence of enhanced BER activities was found in irradiated cells arrested in G2 phase.
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Affiliation(s)
- M Ahmad Chaudhry
- Department of Medical Laboratory and Radiation Sciences, University of Vermont, Burlington, VT 05405, USA.
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Conlon KA, Berrios M. Site-directed photoproteolysis of 8-oxoguanine DNA glycosylase 1 (OGG1) by specific porphyrin-protein probe conjugates: a strategy to improve the effectiveness of photodynamic therapy for cancer. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2006; 87:9-17. [PMID: 17251034 PMCID: PMC1868704 DOI: 10.1016/j.jphotobiol.2006.12.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2006] [Revised: 11/22/2006] [Accepted: 12/02/2006] [Indexed: 01/10/2023]
Abstract
The specific light-induced, non-enzymatic photolysis of mOGG1 by porphyrin-conjugated or rose bengal-conjugated streptavidin and porphyrin-conjugated or rose bengal-conjugated first specific or secondary anti-IgG antibodies is reported. The porphyrin chlorin e6 and rose bengal were conjugated to either streptavidin, rabbit anti-mOGG1 primary specific antibody fractions or goat anti-rabbit IgG secondary antibody fractions. Under our experimental conditions, visible light of wavelengths greater than 600 nm induced the non-enzymatic degradation of mOGG1 when this DNA repair enzyme either directly formed a complex with chlorin e6-conjugated anti-mOGG1 primary specific antibodies or indirectly formed complexes with either streptavidin-chlorin e6 conjugates and biotinylated first specific anti-mOGG1 antibodies or first specific anti-mOGG1 antibodies and chlorin e6-conjugated anti-rabbit IgG secondary antibodies. Similar results were obtained when rose bengal was used as photosensitizer instead of chlorin e6. The rate of the photochemical reaction of mOGG1 site-directed by all three chlorin e6 antibody complexes was not affected by the presence of the singlet oxygen scavenger sodium azide. Site-directed photoactivatable probes having the capacity to generate reactive oxygen species (ROS) while destroying the DNA repair system in malignant cells and tumors may represent a powerful strategy to boost selectivity, penetration and efficacy of current photodynamic (PDT) therapy methodologies.
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Affiliation(s)
- Kimberly A Conlon
- Department of Pharmacological Sciences, School of Medicine, University Hospital and Medical Center, State University of New York, Stony Brook, NY 11794-8651, USA.
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Conlon KA, Miller H, Rosenquist TA, Zharkov DO, Berrios M. The murine DNA glycosylase NEIL2 (mNEIL2) and human DNA polymerase beta bind microtubules in situ and in vitro. DNA Repair (Amst) 2005; 4:419-31. [PMID: 15725623 DOI: 10.1016/j.dnarep.2004.10.010] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2004] [Accepted: 10/29/2004] [Indexed: 12/21/2022]
Abstract
8-oxoguanine DNA glycosylase (OGG1), a major DNA repair enzyme in mammalian cells and a component of the base excision repair (BER) pathway, was recently shown to be associated with the microtubule network and the centriole at interphase and the spindle assembly at mitosis. In this study, we determined whether other participants in the BER pathway also bind microtubules in situ and in vitro. Purified recombinant human DNA polymerase beta (DNA Pol beta) and purified recombinant mNEIL2 were chemically conjugated to fluorochromes and photosensitive dyes and used in in situ localization and binding experiments. Results from in situ localization, microtubule co-precipitation and site-directed photochemical experiments showed that recombinant human DNA Pol beta and recombinant mNEIL2 associated with microtubules in situ and in vitro in a manner similar to that shown earlier for another BER pathway component, OGG1. Observations reported in this study suggest that these BER pathway components are microtubule-associated proteins (MAPs) themselves or utilize yet to be identified MAPs to bind microtubules in order to regulate their intracellular trafficking and activities during the cell cycle.
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Affiliation(s)
- Kimberly A Conlon
- Department of Pharmacological Sciences, School of Medicine University Hospital and Medical Center, State University of New York Stony Brook, NY 11794 8651, USA
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