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RecA acts as a switch to regulate polymerase occupancy in a moving replication fork.

ABSTRACT: This report discovers a role of Escherichia coli RecA, the cellular recombinase, in directing the action of several DNA polymerases at the replication fork. Bulk chromosome replication is performed by DNA polymerase (Pol) III. However, E. coli contains translesion synthesis (TLS) Pols II, IV, and V that also function with the helicase, primase, and sliding clamp in the replisome. Surprisingly, we find that RecA specifically activates replisomes that contain TLS Pols. In sharp contrast, RecA severely inhibits the Pol III replisome. Given the opposite effects of RecA on Pol III and TLS replisomes, we propose that RecA acts as a switch to regulate the occupancy of polymerases within a moving replisome.

SUBMITTER: Indiani C

PROVIDER: S-EPMC3619308 | biostudies-literature | 2013 Apr

REPOSITORIES: biostudies-literature

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RecA acts as a switch to regulate polymerase occupancy in a moving replication fork.

Indiani Chiara C Patel Meghna M Goodman Myron F MF O'Donnell Mike E ME

Proceedings of the National Academy of Sciences of the United States of America 20130318 14

This report discovers a role of Escherichia coli RecA, the cellular recombinase, in directing the action of several DNA polymerases at the replication fork. Bulk chromosome replication is performed by DNA polymerase (Pol) III. However, E. coli contains translesion synthesis (TLS) Pols II, IV, and V that also function with the helicase, primase, and sliding clamp in the replisome. Surprisingly, we find that RecA specifically activates replisomes that contain TLS Pols. In sharp contrast, RecA seve ...[more]

PMID: 23509251

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