Bacillus subtilis RecN binds and protects 3'-single-stranded DNA extensions in the presence of ATP.
Bacillus subtilis RecN appears to be an early detector of breaks in double-stranded DNA. In vivo, RecN forms discrete nucleoid-associated structures and in vitro exhibits Mg2+-dependent single-stranded (ss) DNA binding and ssDNA-dependent ATPase activities. In the presence of ATP or ADP, RecN assembles to form large networks with ssDNA molecules (designated complexes CII and CIII) that involve ATP binding and requires a 3'-OH at the end of ssDNA molecule. Addition of dATP-RecA complexes dissociates RecN from these networks, but this is not observed following addition of an ssDNA binding protein. Apparently, ATP modulates the RecN-ssDNA complex for binding to ssDNA extensions and, in vivo, RecN-ATP bound to 3'-ssDNA might sequester ssDNA ends within complexes that protect the ssDNA while the RecA accessory proteins recruit RecA. With the association of RecA to ssDNA, RecN would dissociate from the DNA end facilitating the subsequent steps in DNA repair.
Sanchez
Humberto
H
Department of Microbial Biotechnology, Centro Nacional de Biotecnología, CSIC, Campus Universidad Autónoma de Madrid Cantoblanco, 28049 Madrid, Spain.
Alonso
Juan C
JC
D000251:Adenosine Triphosphatases / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000378:metabolism*; D001412:Bacillus subtilis; D001426:Bacterial Proteins / Q000378:metabolism*; D001665:Binding Sites; D004260:DNA Repair; D004262:DNA Restriction Enzymes / Q000378:metabolism*; D004277:DNA, Single-Stranded / Q000378:metabolism*; D011485:Protein Binding; D011938:Rec A Recombinases / Q000378:metabolism
D001426:Bacterial Proteins; D004277:DNA, Single-Stranded; D000255:Adenosine Triphosphate; D011938:Rec A Recombinases; D004262:DNA Restriction Enzymes; C047879:RecN protein, Bacteria; D000251:Adenosine Triphosphatases