The Tof1p-Csm3p protein complex counteracts the Rrm3p helicase to control replication termination of Saccharomyces cerevisiae.

ABSTRACT: Termination of replication forks at the natural termini of the rDNA of Saccharomyces cerevisiae is controlled in a sequence-specific and polar mode by the interaction of the Fob1p replication terminator protein with the tandem Ter sites located in the nontranscribed spacers. Here we show, by both 2D gel analyses and chromatin immunoprecipitations (ChIP), that there exists a second level of global control mediated by the intra-S-phase checkpoint protein complex of Tof1p and Csm3p that protect stalled forks at Ter sites against the activity of the Rrm3p helicase ("sweepase"). The sweepase tends to release arrested forks presumably by the transient displacement of the Ter-bound Fob1p. Consistent with this mechanism, very few replication forks were arrested at the natural replication termini i

SUBMITTER: Mohanty BK 

PROVIDER: S-EPMC1347974 | biostudies-literature | 2006 Jan

REPOSITORIES: biostudies-literature