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Structural investigation of DNA polymerase switching during translesion DNA synthesis


EMSL Project ID
51777

Abstract

DNA lesions are frequently introduced throughout genomes by a variety of biological and environmental agents. When encountered, these lesions can stall DNA replication machinery and the stalling can be rescued by translesion DNA synthesis (TLS). TLS has been hypothesized to go through "polymerase switching" whereby a stalled high-fidelity replicative DNA polymerase is replaced by a specialized DNA polymerase capable of bypassing the damaged site, and the switching is facilitated by proliferating cellular nuclear antigen (PCNA), an essential replication factor. For example, Sulfolobus solfataricus, an Archaeon, employs the replicative DNA polymerase PolB1, the DNA lesion bypass polymerase Dpo4, and a heterotrimeric PCNA to perform polymerase switching in vivo. Since the mechanism of polymerase switching is not well understood, the PI proposes to use single-particle Cryo-EM to structurally investigate polymerase switching complexes. Specifically, the PI plans to obtain high-resolution structures of the complexes of Dpo4/PolB1/PCNA and Dpo4/PolB1/PCNA/DNA (undamaged or damaged).

Project Details

Start Date
2020-12-15
End Date
2021-03-17
Status
Closed

Team

Principal Investigator

Zucai Suo
Institution
Florida State University

Team Members

Dhakaram Pangeni Sharma
Institution
Florida State University