title: Drosophila IRBP bZIP heterodimer binds P-element DNA and affects hybrid dysgenesis.
abstract: In Drosophila, P-element transposition causes mutagenesis and genome instability during hybrid dysgenesis. The P-element 31-bp terminal inverted repeats (TIRs) contain sequences essential for transposase cleavage and have been implicated in DNA repair via protein-DNA interactions with cellular proteins. The identity and function of these cellular proteins were unknown. Biochemical characterization of proteins that bind the TIRs identified a heterodimeric basic leucine zipper (bZIP) complex between an uncharacterized protein that we termed "Inverted Repeat Binding Protein (IRBP) 18" and its partner Xrp1. The reconstituted IRBP18/Xrp1 heterodimer binds sequence-specifically to its dsDNA-binding site within the P-element TIRs. Genetic analyses implicate both proteins as critical for repair of DNA breaks following transposase cleavage in vivo. These results identify a cellular protein complex that binds an active mobile element and plays a more general role in maintaining genome stability.
authors: Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720.
authors: Malik Joseph
authors: MJ
authors: Francis
authors: Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720.
authors: Siobhan
authors: S
authors: Roche
authors: Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720.
authors: Michael Jeffrey
authors: 0000-0002-4628-303X
authors: MJ
authors: Cho
authors: Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720.
authors: Eileen
authors: E
authors: Beall
authors: Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720.
authors: Bosun
authors: B
authors: Min
authors: Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720.
authors: Ronaldo Paolo
authors: RP
authors: Panganiban
authors: Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720; don_rio@berkeley.edu.|Center for RNA Systems Biology, University of California, Berkeley, CA 94720.|California Institute for Quantitative Biosciences, University of California, Berkeley, CA 94720.
authors: Donald C
authors: DC
authors: Rio
mesh_terms: D000818:Animals; D004247:DNA / Q000378:metabolism; D004249:DNA Damage; D004260:DNA Repair; D004251:DNA Transposable Elements; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism*; D004330:Drosophila / Q000235:genetics / Q000378:metabolism; D029721:Drosophila Proteins / Q000235:genetics* / Q000378:metabolism*; D009154:Mutation; D009687:Nuclear Proteins / Q000235:genetics* / Q000378:metabolism*; D055503:Protein Multimerization
chemical_list: D004251:DNA Transposable Elements; D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; C086846:Irbp protein, Drosophila; D009687:Nuclear Proteins; C582780:Xrp1 protein, Drosophila; D004247:DNA
keywords: DNA repair; IRBP complex; IRBP18/CG6272; P-transposable elements; Xrp1/CG17836