title: RAD54 family translocases counter genotoxic effects of RAD51 in human tumor cells.
abstract: The RAD54 family DNA translocases have several biochemical activities. One activity, demonstrated previously for the budding yeast translocases, is ATPase-dependent disruption of RAD51-dsDNA binding. This activity is thought to promote dissociation of RAD51 from heteroduplex DNA following strand exchange during homologous recombination. In addition, previous experiments in budding yeast have shown that the same activity of Rad54 removes Rad51 from undamaged sites on chromosomes; mutants lacking Rad54 accumulate nonrepair-associated complexes that can block growth and lead to chromosome loss. Here, we show that human RAD54 also promotes the dissociation of RAD51 from dsDNA and not ssDNA. We also show that translocase depletion in tumor cell lines leads to the accumulation of RAD51 on chromosomes, forming complexes that are not associated with markers of DNA damage. We further show that combined depletion of RAD54L and RAD54B and/or artificial induction of RAD51 overexpression blocks replication and promotes chromosome segregation defects. These results support a model in which RAD54L and RAD54B counteract genome-destabilizing effects of direct binding of RAD51 to dsDNA in human tumor cells. Thus, in addition to having genome-stabilizing DNA repair activity, human RAD51 has genome-destabilizing activity when expressed at high levels, as is the case in many human tumors.
authors.affiliation: Department of Radiation and Cellular Oncology, University of Chicago, Cummings Life Science Center, Box 13, 920 East 58th St., Chicago, IL 60637, USA.
authors.forename: Jennifer M
authors.initials: JM
authors.lastname: Mason
authors.affiliation: Department of Radiation and Cellular Oncology, University of Chicago, Cummings Life Science Center, Box 13, 920 East 58th St., Chicago, IL 60637, USA.
authors.forename: Kritika
authors.initials: K
authors.lastname: Dusad
authors.affiliation: Department of Molecular and Cellular Biology, University of California, Davis, Davis CA 95616, USA.
authors.forename: William Douglass
authors.initials: WD
authors.lastname: Wright
authors.affiliation: Department of Radiation and Cellular Oncology, University of Chicago, Cummings Life Science Center, Box 13, 920 East 58th St., Chicago, IL 60637, USA.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Grubb
authors.affiliation: Department of Radiation and Cellular Oncology, University of Chicago, Cummings Life Science Center, Box 13, 920 East 58th St., Chicago, IL 60637, USA.
authors.forename: Brian
authors.initials: B
authors.lastname: Budke
authors.affiliation: Department of Molecular and Cellular Biology, University of California, Davis, Davis CA 95616, USA Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL 60637, USA.
authors.forename: Wolf-Dietrich
authors.initials: WD
authors.lastname: Heyer
authors.affiliation: Department of Radiation and Cellular Oncology, University of Chicago, Cummings Life Science Center, Box 13, 920 East 58th St., Chicago, IL 60637, USA.
authors.forename: Philip P
authors.initials: PP
authors.lastname: Connell
authors.affiliation: Department of Radiation and Cellular Oncology, University of Chicago, Cummings Life Science Center, Box 13, 920 East 58th St., Chicago, IL 60637, USA.
authors.forename: Ralph R
authors.initials: RR
authors.lastname: Weichselbaum
authors.affiliation: Department of Radiation and Cellular Oncology, University of Chicago, Cummings Life Science Center, Box 13, 920 East 58th St., Chicago, IL 60637, USA Department of Microbiology and Molecular Genetics, University of California, Davis, Davis CA 95616, USA dbishop@uchicago.edu.
authors.forename: Douglas K
authors.initials: DK
authors.lastname: Bishop
mesh_terms: D045744:Cell Line, Tumor; D049109:Cell Proliferation; D004265:DNA Helicases / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D004260:DNA Repair; D004273:DNA, Neoplasm / Q000235:genetics / Q000378:metabolism; D004268:DNA-Binding Proteins; D006801:Humans; D061986:MCF-7 Cells; D046912:Multiprotein Complexes / Q000235:genetics / Q000378:metabolism; D009153:Mutagens / Q000378:metabolism; D009369:Neoplasms / Q000235:genetics* / Q000378:metabolism* / Q000473:pathology; D009687:Nuclear Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D034741:RNA, Small Interfering / Q000235:genetics; D051135:Rad51 Recombinase / Q000235:genetics / Q000378:metabolism*; D051716:Replication Protein A / Q000235:genetics / Q000378:metabolism
chemical_list: D004273:DNA, Neoplasm; D004268:DNA-Binding Proteins; D046912:Multiprotein Complexes; D009153:Mutagens; D009687:Nuclear Proteins; C491221:RAD54B protein, human; D034741:RNA, Small Interfering; C497167:RPA1 protein, human; D051716:Replication Protein A; C495153:RAD51 protein, human; D051135:Rad51 Recombinase; D004265:DNA Helicases; C103532:RAD54L protein, human