The effect of sequence context on spontaneous Polzeta-dependent mutagenesis in Saccharomyces cerevisiae.

Published

Journal Article

The Polzeta translesion synthesis (TLS) DNA polymerase is responsible for over 50% of spontaneous mutagenesis and virtually all damage-induced mutagenesis in yeast. We previously demonstrated that reversion of the lys2DeltaA746 -1 frameshift allele detects a novel type of +1 frameshift that is accompanied by one or more base substitutions and depends completely on the activity of Polzeta. These 'complex' frameshifts accumulate at two discrete hotspots (HS1 and HS2) in the absence of nucleotide excision repair, and accumulate at a third location (HS3) in the additional absence of the translesion polymerase Poleta. The current study investigates the sequence requirements for accumulation of Polzeta-dependent complex frameshifts at these hotspots. We observed that transposing 13 bp of identity from HS1 or HS3 to a new location within LYS2 was sufficient to recapitulate these hotspots. In addition, altering the sequence immediately upstream of HS2 had no effect on the activity of the hotspot. These data support a model in which misincorporation opposite a lesion precedes and facilitates the selected slippage event. Finally, analysis of nonsense mutation revertants indicates that Polzeta can simultaneously introduce multiple base substitutions in the absence of an accompanying frameshift event.

Full Text

Duke Authors

Cited Authors

  • Abdulovic, AL; Minesinger, BK; Jinks-Robertson, S

Published Date

  • April 2008

Published In

Volume / Issue

  • 36 / 6

Start / End Page

  • 2082 - 2093

PubMed ID

  • 18276637

Pubmed Central ID

  • 18276637

Electronic International Standard Serial Number (EISSN)

  • 1362-4962

Digital Object Identifier (DOI)

  • 10.1093/nar/gkn054

Language

  • eng

Conference Location

  • England