1d8l | pdb_00001d8l
E. COLI HOLLIDAY JUNCTION BINDING PROTEIN RUVA NH2 REGION LACKING DOMAIN III
Structural highlights
Function[RUVA_ECOLI] The RuvA-RuvB complex in the presence of ATP renatures cruciform structure in supercoiled DNA with palindromic sequence, indicating that it may promote strand exchange reactions in homologous recombination. RuvAB is a helicase that mediates the Holliday junction migration by localized denaturation and reannealing. RuvA stimulates, in the presence of DNA, the weak ATPase activity of RuvB. Binds both single- and double-stranded DNA (dsDNA). Binds preferentially to supercoiled rather than to relaxed dsDNA.[1] Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedIn prokaryotes, RuvA-RuvB complexes play a crucial role in the migration of the Holliday junction, which is a key intermediate of homologous recombination. RuvA binds to the Holliday junction and enhances the ATPase activity of RuvB required for branch migration. RuvA adopts a unique domain structure, which assembles into a tetrameric molecule. The previous mutational and proteolytic analyses suggested that mutations in a carboxyl-terminal domain (domain III) impair binding of RuvA to RuvB. In order to clarify the functional role of each domain in vitro, we established the recombinant expression systems, which allow us to analyze structural and biochemical properties of each domain separately. A small-angle X-ray scattering solution study, combined with X-ray crystallographic analyses, was applied to the tetrameric full-length RuvA and its tetrameric NH2 region (domains I and II) lacking the domain III. These results demonstrated that domain III can be completely separate from the tetrameric major core of the NH2 region and freely mobile in solution, through a remarkably flexible loop. Biochemical analyses indicated that domain III not only interacts with RuvB, but also modulates its ATPase activity. This modulation may facilitate the dynamic coupling between RuvA and RuvB during branch migration. Modulation of RuvB function by the mobile domain III of the Holliday junction recognition protein RuvA.,Nishino T, Iwasaki H, Kataoka M, Ariyoshi M, Fujita T, Shinagawa H, Morikawa K J Mol Biol. 2000 May 5;298(3):407-16. PMID:10772859[2] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
| ||||||||||||||||
