Allosteric regulation of the primase (DnaG) activity by the clamp-loader (tau) in vitro.

ABSTRACT: During DNA replication the helicase (DnaB) recruits the primase (DnaG) in the replisome to initiate the polymerization of new DNA strands. DnaB is attached to the tau subunit of the clamp-loader that loads the beta clamp and interconnects the core polymerases on the leading and lagging strands. The tau-DnaB-DnaG ternary complex is at the heart of the replisome and its function is likely to be modulated by a complex network of allosteric interactions. Using a stable ternary complex comprising the primase and helicase from Geobacillus stearothermophilus and the tau subunit of the clamp-loader from Bacillus subtilis we show that changes in the DnaB-tau interaction can stimulate allosterically primer synthesis by DnaG in vitro. The A550V tau mutant stimulates the primase activity more efficien

SUBMITTER: Chintakayala K 

PROVIDER: S-EPMC3035870 | biostudies-literature | 2009 Apr

REPOSITORIES: biostudies-literature