title: Ubiquitin-dependent regulation of translesion polymerases.
abstract: In response to DNA damage, TLS (translesion synthesis) allows replicative bypass of various DNA lesions, which stall normal replication. TLS is achieved by low-fidelity polymerases harbouring less stringent active sites. In humans, Y-family polymerases together with Pol zeta (polymerase zeta) are responsible for TLS across different types of damage. Protein-protein interaction contributes significantly to the regulation of TLS. REV1 plays a central role in TLS because it interacts with all other Y-family members and Pol zeta. Ubiquitin-dependent regulatory mechanisms also play important roles in TLS. Ubiquitin-binding domains have been found in TLS polymerases and they might be required for TLS activity. Mono-ubiquitination of PCNA (proliferating-cell nuclear antigen), the central scaffold of TLS polymerases, is thought to promote TLS. In addition, both non-proteolytic and proteolytic polyubiquitination of PCNA and TLS polymerases has been demonstrated. Owing to their low fidelity, the recruitment of TLS polymerases is strictly restricted to stalled replication forks.
authors.affiliation: Department of Biochemistry, The University of Hong Kong, 21 Sassoon Road, Pokfulam, Hong Kong.
authors.forename: Abel C S
authors.initials: AC
authors.lastname: Chun
authors.forename: Dong-Yan
authors.initials: DY
authors.lastname: Jin
mesh_terms: D000818:Animals; D002453:Cell Cycle / Q000502:physiology; D004249:DNA Damage; D004260:DNA Repair; D004261:DNA Replication; D004259:DNA-Directed DNA Polymerase / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D007527:Isoenzymes / Q000235:genetics / Q000378:metabolism; D018809:Proliferating Cell Nuclear Antigen / Q000235:genetics / Q000378:metabolism; D025801:Ubiquitin / Q000378:metabolism*; D054875:Ubiquitination
chemical_list: D007527:Isoenzymes; D018809:Proliferating Cell Nuclear Antigen; D025801:Ubiquitin; D004259:DNA-Directed DNA Polymerase