Replication Studies of Ethylated Thymidine Adducts In Vitro and In Vivo

摘要

In vitro Replication Experiments: (1) DNA synthesis mediated by human polymerase opposite all three ethylated lesions was mostly error-free and resulted primarily in full length extension products; (2) All three ethylated lesions were highly blocking and miscoding during DNA synthesis mediated by human polymerase with both Mg~(2+) and Mn~(2+) divalent cations; (3)Opposite O~4-edT and N3-edT, DNA synthesis carried out by human polymerase was highly blocking and error-prone, while DNA synthesis opposite O~2-edT was also error-prone, but resulted in more full length extension products; (4) O~2-edT and N3-edT were both strong blocks and mutagenic during DNA synthesis mediated by Klenow fragment exo- and yeast polymeraseζ while O~4-edT was easily bypassed by both these DNA polymerases.