A genome-wide homologous recombination screen identifies the RNA-binding protein RBMX as a component of the DNA-damage response. Author Britt Adamson, Agata Smogorzewska, Frederic Sigoillot, Randall King, Stephen Elledge Publication Year 2012 Type Journal Article 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. Keywords RNA-Binding Proteins, Nuclear Proteins, Humans, Transcription Factors, Microscopy, Fluorescence, Green Fluorescent Proteins, Models, Genetic, Immunoblotting, Cell Cycle Proteins, Reverse Transcriptase Polymerase Chain Reaction, Cell Line, Tumor, RNA Interference, RNA, Small Interfering, DNA Damage, Gene Regulatory Networks, Genome, Human, DNA Repair, Homologous Recombination, Poly(ADP-ribose) Polymerases, BRCA2 Protein, Heterogeneous-Nuclear Ribonucleoproteins, Histone Chaperones, Nuclear Pore Complex Proteins, RNA Precursors, Rad51 Recombinase Journal Nat Cell Biol Volume 14 Issue 3 Pages 318-28 Date Published 2012 Feb 19 ISSN Number 1476-4679 DOI 10.1038/ncb2426 Alternate Journal Nat Cell Biol PMCID PMC3290715 PMID 22344029 PubMedPubMed CentralGoogle ScholarBibTeXEndNote X3 XML