Identification of a cAMP-dependent protein-DNA interaction at a sequence near the yeast mitochondrial rRNA genes.
We have shown that expression of yeast mitochondrial (mt) rRNA genes (S. cerevisiae) is controlled in a cAMP-dependent manner via PKA, suggesting a trans-activation process involving phosphorylation-dependent protein-mt DNA interaction. We used filter-binding assays, mt protein extracts, and mt DNA from a rho-mutant strain retaining the 21S rRNA gene to demonstrate such an interaction. Competition assays with the cloned 21S-related mt DNA fragment undergoing interaction showed that a sequence in that fragment is present in mt DNA from a rho-strain retaining the 16S mt rRNA gene, but not in a VAR1-retaining rho-strain that lacks cAMP-mediated mt transcription. The sequence of the 21S-related mt DNA fragment undergoing protein interaction includes a GC cluster; that GC cluster sequence is also present near the 16S gene but not near VAR1. These and other data are consistent with a role for the GC cluster in cAMP-mediated expression of mt rRNA genes.
Rahman
M U
MU
Dept. Microbiology and Immunology, Medical College of Pennsylvania-Hahnemann University, PA 19104, USA.
Iqbal
J
J
Salameh
W A
WA
Nevel-McGarvey
C A
CA
Hudson
A P
AP
D000242:Cyclic AMP / Q000235:genetics / Q000378:metabolism*; D017868:Cyclic AMP-Dependent Protein Kinases / Q000378:metabolism; D004272:DNA, Mitochondrial / Q000235:genetics / Q000378:metabolism*; D005656:Fungal Proteins / Q000378:metabolism*; D015966:Gene Expression Regulation, Fungal; D008928:Mitochondria / Q000378:metabolism; D012335:RNA, Ribosomal / Q000235:genetics*; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism*; D014158:Transcription, Genetic
D004272:DNA, Mitochondrial; D005656:Fungal Proteins; D012335:RNA, Ribosomal; D000242:Cyclic AMP; D017868:Cyclic AMP-Dependent Protein Kinases