Mechanism of SOS mutagenesis of UV-irradiated DNA: mostly error-free processing of deaminated cytosine - PubMed (original) (raw)

Mechanism of SOS mutagenesis of UV-irradiated DNA: mostly error-free processing of deaminated cytosine

I Tessman et al. Proc Natl Acad Sci U S A. 1992.

Abstract

We measured the kinetics of growth and mutagenesis of UV-irradiated DNA of phages S13 and lambda that were undergoing SOS repair; the kinetics strongly suggest that most of SOS mutagenesis arises from the deamination of cytosine in cyclobutane pyrimidine dimers, producing C----T transitions. This occurs because the SOS mechanism bypasses T--T dimers promptly, while bypass of cytosine-containing dimers is delayed long enough for deamination to occur. The mutations are thus primarily the product of a faithful mechanism of lesion bypass by a DNA polymerase and are not, as had been generally thought, the product of an error-prone mechanism. All of these observations are explained by the A-rule, which is that adenine nucleotides are inserted noninstructionally opposite DNA lesions.

PubMed Disclaimer

Similar articles

Cited by

References

    1. Proc Natl Acad Sci U S A. 1953 Jul;39(7):628-36 - PubMed
    1. Proc Natl Acad Sci U S A. 1983 Jan;80(2):487-91 - PubMed
    1. J Bacteriol. 1958 Mar;75(3):310-5 - PubMed
    1. J Biol Chem. 1957 Oct;228(2):601-9 - PubMed
    1. Mol Gen Genet. 1991 May;227(1):144-8 - PubMed

Publication types

MeSH terms

Substances

LinkOut - more resources