Amino acid substitutions conferring cold-sensitive phenotype on the yeast MTF1 gene

作者：Jang SH

来源：Journal of Microbiology, 1997, 35(3): 228-233.

• mitochondrial transcription
• MTF1
• yeast mitochondrial RNA polymerase

The MTF1 gene of Saccharomyces cerevisiae encodes a 43 kDa mitochondrial RNA polymerase specificity factor which recognizes mitochondrial promoters to initiate correct transcription. To better understand structure-function of the MTF1 gene as well as the transcription mechanism of mitochondrial RNA polymerase, two cold-sensitive alleles of the MTF1 mutation were isolated by plasmid shuffling method after PCR-based random mutagenesis of the MTF1 gene. The mutation sites were analyzed by nucleotide sequencing. These cs(-) phenotype mtf1 mutants were respiration competent on the nonfermentible glycerol medium at the permissive temperature, but incompetent at 13 degrees C. The cs(-) phenotype allele of the MTF1, yJH147, encoded an L146P replacement. The other cs(-) allele, yJH148, contained K179E and K214M double replacements. Mutations in both alleles were in a region of Mtf1p which is located between domains with amino acid sequence similarities to conserved regions 2 and 3 of bacterial s factors.

• 出版日期1997-9