title: A genome-wide homologous recombination screen identifies the RNA-binding protein RBMX as a component of the DNA-damage response.
abstract: Repair of DNA double-strand breaks is critical to genomic stability and the prevention of developmental disorders and cancer. A central pathway for this repair is homologous recombination (HR). Most knowledge of HR is derived from work in prokaryotic and eukaryotic model organisms. We carried out a genome-wide siRNA-based screen in human cells. Among positive regulators of HR we identified networks of DNA-damage-response and pre-mRNA-processing proteins, and among negative regulators we identified a phosphatase network. Three candidate proteins localized to DNA lesions, including RBMX, a heterogeneous nuclear ribonucleoprotein that has a role in alternative splicing. RBMX accumulated at DNA lesions through multiple domains in a poly(ADP-ribose) polymerase 1-dependent manner and promoted HR by facilitating proper BRCA2 expression. Our screen also revealed that off-target depletion of RAD51 is a common source of RNAi false positives, raising a cautionary note for siRNA screens and RNAi-based studies of HR.
authors.affiliation: Howard Hughes Medical Institute, Department of Genetics, Harvard Medical School, Division of Genetics, Brigham and Women's Hospital, Boston, Massachusetts 02115, USA.
authors.forename: Britt
authors.initials: B
authors.lastname: Adamson
authors.forename: Agata
authors.initials: A
authors.lastname: Smogorzewska
authors.forename: Frederic D
authors.initials: FD
authors.lastname: Sigoillot
authors.forename: Randall W
authors.initials: RW
authors.lastname: King
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Elledge
mesh_terms: D024682:BRCA2 Protein / Q000235:genetics / Q000378:metabolism; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism; D045744:Cell Line, Tumor; D004249:DNA Damage; D004260:DNA Repair; D053263:Gene Regulatory Networks; D015894:Genome, Human / Q000235:genetics*; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D034441:Heterogeneous-Nuclear Ribonucleoproteins / Q000235:genetics* / Q000378:metabolism; D056488:Histone Chaperones / Q000235:genetics / Q000378:metabolism; D059765:Homologous Recombination; D006801:Humans; D015151:Immunoblotting; D008856:Microscopy, Fluorescence; D008957:Models, Genetic; D028861:Nuclear Pore Complex Proteins / Q000235:genetics / Q000378:metabolism; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism; D011065:Poly(ADP-ribose) Polymerases / Q000235:genetics / Q000378:metabolism; D034622:RNA Interference; D012322:RNA Precursors / Q000235:genetics / Q000378:metabolism; D034741:RNA, Small Interfering / Q000235:genetics; D016601:RNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D051135:Rad51 Recombinase / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism
chemical_list: D024682:BRCA2 Protein; D018797:Cell Cycle Proteins; C086057:HIRA protein, human; D034441:Heterogeneous-Nuclear Ribonucleoproteins; D056488:Histone Chaperones; C085914:NUP214 protein, human; D028861:Nuclear Pore Complex Proteins; D009687:Nuclear Proteins; C510272:RBMX protein, human; D012322:RNA Precursors; D034741:RNA, Small Interfering; D016601:RNA-Binding Proteins; D014157:Transcription Factors; C406814:UBN1 protein, human; D049452:Green Fluorescent Proteins; D011065:Poly(ADP-ribose) Polymerases; D051135:Rad51 Recombinase