DNA polymerase V activity is autoregulated by a novel intrinsic DNA-dependent ATPase
Aysen L Erdem,
Malgorzata Jaszczur,
Jeffrey G Bertram,
Roger Woodgate,
Michael M Cox,
Myron F Goodman
Affiliations
Aysen L Erdem
Department of Biological Sciences, University of Southern California, Los Angeles, United States
Malgorzata Jaszczur
Department of Biological Sciences, University of Southern California, Los Angeles, United States
Jeffrey G Bertram
Department of Biological Sciences, University of Southern California, Los Angeles, United States
Roger Woodgate
Laboratory of Genomic Integrity, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, United States
Michael M Cox
Department of Biochemistry, University of Wisconsin–Madison, Madison, United States
Myron F Goodman
Department of Biological Sciences, University of Southern California, Los Angeles, United States; Department of Chemistry, University of Southern California, Los Angeles, United States
Escherichia coli DNA polymerase V (pol V), a heterotrimeric complex composed of UmuD′2C, is marginally active. ATP and RecA play essential roles in the activation of pol V for DNA synthesis including translesion synthesis (TLS). We have established three features of the roles of ATP and RecA. (1) RecA-activated DNA polymerase V (pol V Mut), is a DNA-dependent ATPase; (2) bound ATP is required for DNA synthesis; (3) pol V Mut function is regulated by ATP, with ATP required to bind primer/template (p/t) DNA and ATP hydrolysis triggering dissociation from the DNA. Pol V Mut formed with an ATPase-deficient RecA E38K/K72R mutant hydrolyzes ATP rapidly, establishing the DNA-dependent ATPase as an intrinsic property of pol V Mut distinct from the ATP hydrolytic activity of RecA when bound to single-stranded (ss)DNA as a nucleoprotein filament (RecA*). No similar ATPase activity or autoregulatory mechanism has previously been found for a DNA polymerase.
