1
|
Law S, Park H, Shany E, Sandhu S, Vallabhaneni M, Meyer D. Expression of human BRCA2 in Saccharomyces cerevisiae complements the loss of RAD52 in double-strand break repair. Curr Genet 2023; 69:301-308. [PMID: 37934232 DOI: 10.1007/s00294-023-01278-y] [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: 10/09/2023] [Revised: 10/30/2023] [Accepted: 10/31/2023] [Indexed: 11/08/2023]
Abstract
BRCA2 is a tumor-suppressor gene that is normally expressed in the breast and ovarian tissue of mammals. The BRCA2 protein mediates the repair of double-strand breaks (DSBs) using homologous recombination, which is a conserved pathway in eukaryotes. Women who express missense mutations in the BRCA2 gene are predisposed to an elevated lifetime risk for both breast cancer and ovarian cancer. In the present study, the efficiency of human BRCA2 (hBRCA2) in DSB repair was investigated in the budding yeast Saccharomyces cerevisiae. While budding yeast does not possess a true BRCA2 homolog, they have a potential functional homolog known as Rad52, which is an essential repair protein involved in mediating homologous recombination using the same mechanism as BRCA2 in humans. Therefore, to examine the functional overlap between Rad52 in yeast and hBRCA2, we expressed the wild-type hBRCA2 gene in budding yeast with or without Rad52 and monitored ionizing radiation resistance and DSB repair efficiency. We found that the expression of hBRCA2 in rad52 mutants increases both radiation resistance and DSB repair frequency compared to cells not expressing BRCA2. Specifically, BRCA2 improved the protection against ionizing radiation by at least 1.93-fold and the repair frequency by 6.1-fold. In addition, our results show that homology length influences repair efficiency in rad52 mutant cells, which impacts BRCA2 mediated repair of DSBs. This study provides evidence that S. cerevisiae could be used to monitor BRCA2 function, which can help in understanding the genetic consequences of BRCA2 variants and how they may contribute to cancer progression.
Collapse
Affiliation(s)
- Sherrice Law
- College of Medicine, California Northstate University, Elk Grove, CA, 95757, USA
| | - Hannah Park
- College of Medicine, California Northstate University, Elk Grove, CA, 95757, USA
| | - Eyar Shany
- Columbia University, New York, NY, 10027, USA
| | - Sumer Sandhu
- University of Tennessee College of Medicine, Memphis, TN, 38163, USA
| | - Mayukha Vallabhaneni
- College of Health Sciences, California Northstate University, Rancho Cordova, CA, 95670, USA
| | - Damon Meyer
- College of Health Sciences, California Northstate University, Rancho Cordova, CA, 95670, USA.
| |
Collapse
|
2
|
Lima-Noronha MA, Fonseca DLH, Oliveira RS, Freitas RR, Park JH, Galhardo RS. Sending out an SOS - the bacterial DNA damage response. Genet Mol Biol 2022; 45:e20220107. [PMID: 36288458 PMCID: PMC9578287 DOI: 10.1590/1678-4685-gmb-2022-0107] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Accepted: 07/15/2022] [Indexed: 11/04/2022] Open
Abstract
The term “SOS response” was first coined by Radman in 1974, in an intellectual effort to put together the data suggestive of a concerted gene expression program in cells undergoing DNA damage. A large amount of information about this cellular response has been collected over the following decades. In this review, we will focus on a few of the relevant aspects about the SOS response: its mechanism of control and the stressors which activate it, the diversity of regulated genes in different species, its role in mutagenesis and evolution including the development of antimicrobial resistance, and its relationship with mobile genetic elements.
Collapse
Affiliation(s)
- Marco A. Lima-Noronha
- Universidade de São Paulo, Instituto de Ciências Biomédicas, Departamento de Microbiologia, São Paulo, SP, Brazil
| | - Douglas L. H. Fonseca
- Universidade de São Paulo, Instituto de Ciências Biomédicas, Departamento de Microbiologia, São Paulo, SP, Brazil
| | - Renatta S. Oliveira
- Universidade de São Paulo, Instituto de Ciências Biomédicas, Departamento de Microbiologia, São Paulo, SP, Brazil
| | - Rúbia R. Freitas
- Universidade de São Paulo, Instituto de Ciências Biomédicas, Departamento de Microbiologia, São Paulo, SP, Brazil
| | - Jung H. Park
- Universidade de São Paulo, Instituto de Ciências Biomédicas, Departamento de Microbiologia, São Paulo, SP, Brazil
| | - Rodrigo S. Galhardo
- Universidade de São Paulo, Instituto de Ciências Biomédicas, Departamento de Microbiologia, São Paulo, SP, Brazil
| |
Collapse
|
3
|
Payne-Dwyer AL, Syeda AH, Shepherd JW, Frame L, Leake MC. RecA and RecB: probing complexes of DNA repair proteins with mitomycin C in live Escherichia coli with single-molecule sensitivity. JOURNAL OF THE ROYAL SOCIETY, INTERFACE 2022; 19:20220437. [PMID: 35946163 PMCID: PMC9363994 DOI: 10.1098/rsif.2022.0437] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The RecA protein and RecBCD complex are key bacterial components for the maintenance and repair of DNA. RecBCD is a helicase-nuclease that uses homologous recombination to resolve double-stranded DNA breaks. It also facilitates coating of single-stranded DNA with RecA to form RecA filaments, a vital step in the double-stranded break DNA repair pathway. However, questions remain about the mechanistic roles of RecA and RecBCD in live cells. Here, we use millisecond super-resolved fluorescence microscopy to pinpoint the spatial localization of fluorescent reporters of RecA or RecB at physiological levels of expression in individual live Escherichia coli cells. By introducing the DNA cross-linker mitomycin C, we induce DNA damage and quantify the resulting steady state changes in stoichiometry, cellular protein copy number and molecular mobilities of RecA and RecB. We find that both proteins accumulate in molecular hotspots to effect repair, resulting in RecA stoichiometries equivalent to several hundred molecules that assemble largely in dimeric subunits before DNA damage, but form periodic subunits of approximately 3-4 molecules within mature filaments of several thousand molecules. Unexpectedly, we find that the physiologically predominant forms of RecB are not only rapidly diffusing monomers, but slowly diffusing dimers.
Collapse
Affiliation(s)
- Alex L Payne-Dwyer
- Department of Physics, University of York, York YO10 5DD, UK.,Department of Biology, University of York, York YO10 5DD, UK
| | - Aisha H Syeda
- Department of Physics, University of York, York YO10 5DD, UK.,Department of Biology, University of York, York YO10 5DD, UK
| | - Jack W Shepherd
- Department of Physics, University of York, York YO10 5DD, UK.,Department of Biology, University of York, York YO10 5DD, UK
| | - Lewis Frame
- School of Natural Sciences, University of York, York YO10 5DD, UK
| | - Mark C Leake
- Department of Physics, University of York, York YO10 5DD, UK.,Department of Biology, University of York, York YO10 5DD, UK
| |
Collapse
|
4
|
Molza AE, Westermaier Y, Moutte M, Ducrot P, Danilowicz C, Godoy-Carter V, Prentiss M, Robert CH, Baaden M, Prévost C. Building Biological Relevance Into Integrative Modelling of Macromolecular Assemblies. Front Mol Biosci 2022; 9:826136. [PMID: 35480882 PMCID: PMC9035671 DOI: 10.3389/fmolb.2022.826136] [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: 11/30/2021] [Accepted: 02/21/2022] [Indexed: 01/25/2023] Open
Abstract
Recent advances in structural biophysics and integrative modelling methods now allow us to decipher the structures of large macromolecular assemblies. Understanding the dynamics and mechanisms involved in their biological function requires rigorous integration of all available data. We have developed a complete modelling pipeline that includes analyses to extract biologically significant information by consistently combining automated and interactive human-guided steps. We illustrate this idea with two examples. First, we describe the ryanodine receptor, an ion channel that controls ion flux across the cell membrane through transitions between open and closed states. The conformational changes associated with the transitions are small compared to the considerable system size of the receptor; it is challenging to consistently track these states with the available cryo-EM structures. The second example involves homologous recombination, in which long filaments of a recombinase protein and DNA catalyse the exchange of homologous DNA strands to reliably repair DNA double-strand breaks. The nucleoprotein filament reaction intermediates in this process are short-lived and heterogeneous, making their structures particularly elusive. The pipeline we describe, which incorporates experimental and theoretical knowledge combined with state-of-the-art interactive and immersive modelling tools, can help overcome these challenges. In both examples, we point to new insights into biological processes that arise from such interdisciplinary approaches.
Collapse
Affiliation(s)
- Anne-Elisabeth Molza
- CNRS, Université Paris-Cité, UPR 9080, Laboratoire de Biochimie Théorique, Paris, France
- Institut de Biologie Physico-Chimique-Fondation Edmond de Rothschild, PSL Research University, Paris, France
| | - Yvonne Westermaier
- Biophysics and Modelling Department/In Vitro Pharmacology Unit–IDRS (Servier Research Institute), Croissy-sur-Seine, France
| | | | - Pierre Ducrot
- Biophysics and Modelling Department/In Vitro Pharmacology Unit–IDRS (Servier Research Institute), Croissy-sur-Seine, France
| | | | | | - Mara Prentiss
- Department of Physics, Harvard University, Cambridge, MA, United States
| | - Charles H. Robert
- CNRS, Université Paris-Cité, UPR 9080, Laboratoire de Biochimie Théorique, Paris, France
- Institut de Biologie Physico-Chimique-Fondation Edmond de Rothschild, PSL Research University, Paris, France
| | - Marc Baaden
- CNRS, Université Paris-Cité, UPR 9080, Laboratoire de Biochimie Théorique, Paris, France
- Institut de Biologie Physico-Chimique-Fondation Edmond de Rothschild, PSL Research University, Paris, France
| | - Chantal Prévost
- CNRS, Université Paris-Cité, UPR 9080, Laboratoire de Biochimie Théorique, Paris, France
- Institut de Biologie Physico-Chimique-Fondation Edmond de Rothschild, PSL Research University, Paris, France
- *Correspondence: Chantal Prévost ,
| |
Collapse
|