The "tale" of UmuD and its role in SOS mutagenesis.
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.
Gonzalez
Martín
M
Department of Biology, University of Colorado-Denver, Denver, CO, USA.
Woodgate
Roger
R
D049069:ATP-Dependent Proteases; D000251:Adenosine Triphosphatases / Q000378:metabolism; D000595:Amino Acid Sequence; D001665:Binding Sites; D019951:DNA Polymerase beta / Q000235:genetics* / Q000378:metabolism; D004259:DNA-Directed DNA Polymerase; D049071:Endopeptidase Clp; D004926:Escherichia coli / Q000235:genetics* / Q000502:physiology; D029968:Escherichia coli Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial; D006360:Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism; D008954:Models, Biological; D008958:Models, Molecular; D008969:Molecular Sequence Data; D016296:Mutagenesis; D009876:Operon / Q000235:genetics; D017434:Protein Structure, Tertiary; D011938:Rec A Recombinases / Q000378:metabolism; D013014:SOS Response, Genetics; D012697:Serine Endopeptidases / Q000235:genetics / Q000378:metabolism
D029968:Escherichia coli Proteins; D006360:Heat-Shock Proteins; D011938:Rec A Recombinases; D019951:DNA Polymerase beta; D004259:DNA-Directed DNA Polymerase; C055218:UmuD protein, E coli; D049069:ATP-Dependent Proteases; D012697:Serine Endopeptidases; D049071:Endopeptidase Clp; D000251:Adenosine Triphosphatases