The choice of nucleotide inserted opposite abasic sites formed within chromosomal DNA reveals the polymerase activities participating in translesion DNA synthesis.

ABSTRACT: Abasic sites in genomic DNA can be a significant source of mutagenesis in biological systems, including human cancers. Such mutagenesis requires translesion DNA synthesis (TLS) bypass of the abasic site by specialized DNA polymerases. The abasic site bypass specificity of TLS proteins had been studied by multiple means in vivo and in vitro, although the generality of the conclusions reached have been uncertain. Here, we introduce a set of yeast reporter strains for investigating the in vivo specificity of abasic site bypass at numerous random positions within chromosomal DNA. When shifted to 37°C, these strains underwent telomere uncapping and resection that exposed reporter genes within a long 3' ssDNA overhang. Human APOBEC3G cytosine deaminase was expressed to create uracils in ssDNA, w

SUBMITTER: Chan K 

PROVIDER: S-EPMC3825800 | biostudies-literature | 2013 Nov

REPOSITORIES: biostudies-literature