title: Homology-driven chromatin remodeling by human RAD54.
abstract: Human RAD51 and RAD54 are key players in homologous recombination, a process that requires homology recognition and strand invasion by a RAD51-single-stranded DNA (ssDNA) nucleoprotein filament and chromatin remodeling by RAD54. Here we use in vitro chromatin reconstitution systems to show that RAD51-ssDNA stimulates RAD54-dependent chromatin remodeling in a homology-dependent, polarity-independent manner. This stimulation was not seen with RAD54B or other remodelers. Chromatin remodeling by RAD54 enabled strand invasion by RAD51-ssDNA on nucleosomal templates, which was homology- and polarity-dependent. Three natural RAD54 mutants found in primary cancer cells showed specific defects in remodeling or in the RAD54-RAD51 interaction. We propose that RAD54 is recruited by RAD51-ssDNA filament to the chromatin of the intact chromosome and that it remodels that chromatin to facilitate accessibility for strand exchange.
authors.affiliation: Department of Molecular Biology, Massachusetts General Hospital and Department of Genetics, Harvard Medical School, 185 Cambridge Street, Boston, Massachusetts 02114, USA.
authors.forename: Zhaoqing
authors.initials: Z
authors.lastname: Zhang
authors.forename: Hua-Ying
authors.initials: HY
authors.lastname: Fan
authors.forename: Joseph A
authors.initials: JA
authors.lastname: Goldman
authors.forename: Robert E
authors.initials: RE
authors.lastname: Kingston
mesh_terms: D042002:Chromatin Assembly and Disassembly; D004265:DNA Helicases; D004277:DNA, Single-Stranded / Q000378:metabolism; D004268:DNA-Binding Proteins; D006801:Humans; D009154:Mutation; D009369:Neoplasms / Q000235:genetics; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D009707:Nucleosomes; D011485:Protein Binding; D051135:Rad51 Recombinase / Q000378:metabolism
chemical_list: D004277:DNA, Single-Stranded; D004268:DNA-Binding Proteins; D009687:Nuclear Proteins; D009707:Nucleosomes; C495153:RAD51 protein, human; D051135:Rad51 Recombinase; D004265:DNA Helicases; C103532:RAD54L protein, human