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Updated: Aug 13, 2026

Proofreading and DNA Repair Assay Using Single Nucleotide Extension and MALDI-TOF Mass Spectrometry Analysis
Published on: June 19, 2018
Mitochondrial DNA repair by photolyase
A Yasui1, H Yajima, T Kobayashi
1Research Institute for Tuberculosis and Cancer, Tohoku University, Sendai, Japan.
Abstract:
Photolyase genes of Saccharomyces cerevisiae and Escherichia coli were expressed in S. cerevisiae and photoreactivation in nuclei and mitochondria of the host cells was analyzed by determination of survival and petit rates. Yeast photolyase was able to repair mitochondrial DNA effectively, whereas E. coli photolyase could reduce only a small fraction of the petit rate produced by UV irradiation. Analysis using fusion between yeast photolyase and E. coli lacZ genes as well as a chimeric gene between yeast and E. coli photolyase genes suggests the importance of the protruding amino terminal region of the yeast photolyase for its transport into mitochondria. A significant similarity between the protruding amino termini of yeast photolyase and yeast uracil-DNA-glycosylase suggests a common functional importance of the terminal sequences for both DNA repair enzymes.
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