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Role of Polymerase η in Mitochondrial Mutagenesis of Saccharomyces cerevisiae.

Dept. of Cell Biology and Anatomy, University of North Texas Health Science Center, 3500 Camp Bowie Blvd., Fort Worth, TX 76107, USA.
Biochemical and Biophysical Research Communications (Impact Factor: 2.28). 01/2013; 431(2). DOI: 10.1016/j.bbrc.2012.12.119
Source: PubMed

ABSTRACT DNA polymerase η mostly catalyzes an error-free bypass of the most frequent UV lesions, pyrimidine dimers of the cyclobutane-type. In addition to its nuclear localization, we show here for the first time its mitochondrial localization in budding yeast. In mitochondria, this polymerase improves bypass replication fidelity opposite UV damage as shown in base pair substitution and frameshift assays. For base pair substitutions, polymerase η appears to be related in function and epistatic to DNA polymerase ζ which, however, plays the opposite role in the nucleus.

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Available from: Nimrat Chatterjee, Mar 17, 2015
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