Open AccessMacromolecular Synthesis and Energy Level in a Mitochondrial Conditional Yeast Mutant, tsm ‐8
Author(s) -
BANDLOW Wolfhard,
METZKE Roland,
KLEIN Annemarie,
KOTZIAS Klaus,
DOXIADIS Ilias,
BECHMANN Helga,
SCHWEYEN Rudolf J.,
KAUDEWITZ Fritz
Publication year - 1977
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1977.tb11605.x
Subject(s) - mitochondrial dna , mutant , transcription (linguistics) , yeast , mitochondrion , biochemistry , biology , incubation , microbiology and biotechnology , chemistry , biophysics , gene , philosophy , linguistics
Mitochondrial DNA, protein and ATP syntheses persist at non‐permissive temperature (35°C) in the mitochondrial, conditionally rho − petites forming yeast mutant, tsm8 . Protein and ATP syntheses, however, are diminished during prolonged incubation at 35°C in non‐fermentable substrate. Mitochondrial RNA synthesis decreases rapidly to a residual constant level of about 10% of the initial value after the shift to 35°C. The decrease is reversed by returning to permissive conditions. Evidence is presented that this temperature‐induced decrease in mitochondrial transcription rate is effected by a mutationally altered regulatory process rather than by temperature sensitivity of mitochondrial RNA polymerase. It is concluded that rho − petite formation in mutant tsm8 is not effected by complete inhibition of macromolecular and ATP syntheses but is correlated with a reduction in mitochondrial transcription.