Abstract

Previous results in our laboratory showed that there are site-specific large deletions in yeast Saccharomyces cerevisiae 777-3A mitochondrial oxi3 gene and most of them fall into A and B class only. The B-class mutants were analyzed by PCR and sequencing. About 420 bp deletion junction fragments were successfully amplified and subjected to direct sequencing. Based on the sequencing results, the deletion endpoints of class B-deletions were identified at a distance of 8,222 bp; interestingly, one end(position 26180 coincided with the 3’ splice site(intron/exon junction) of first intron aI1, the other end(position 10,839) was located in the middle of the fifth intron (aI5) of the gene, especially in an open reading frame(ORF).

• Keywords: yeast mtDNA; oxi3 gene; site-specific large-deletion; deletion junction fragments; PCR; direct-dequencing