The “tale” of UmuD and its role in SOS mutagenesis

✍ Scribed by Martín Gonzalez; Roger Woodgate

• Publisher: John Wiley and Sons
• Year: 2002
• Tongue: English
• Weight: 180 KB
• Volume: 24
• Category: Article
• ISSN: 0265-9247
• DOI: 10.1002/bies.10040

✦ Synopsis

Abstract

Recently, the Escherichia coli umuD and umuC genes have been shown to encode E. coli's fifth DNA polymerase, pol V (consisting of a heterotrimer of UmuD′~2~C). The main function of pol V appears to be the bypass of DNA lesions that would otherwise block replication by pols I–IV. This process is error‐prone and leads to a striking increase in mutations at sites of DNA damage. While the enzymatic properties of pol V are now only beginning to be fully appreciated, a great deal is known about how E. coli regulates the intracellular levels of the Umu proteins so that the lesion‐bypassing activity of pol V is available to help cells survive the deleterious consequences of DNA damage, yet keeps any unwarranted activity on undamaged templates to a minimum. Our review summarizes the multiple restrictions imposed upon pol V, so as to limit its activity in vivo and, in particular, highlights the pivotal role that the N‐terminal tail of UmuD plays in regulating SOS mutagenesis. BioEssays 24:141–148, 2002. Published 2002 Wiley Periodicals, Inc.