The role of glucose and aminoacid starvation in the sensitivity of protein and RNA synthesis to cycloheximide and erythromycin in the yeast Saccharomyces cerevisiae.
In Saccharomyces cerevisiae dependence of ribonucleic acid synthesis on protein synthesis occurring during nutritional shift down conditions was evidenced. The results obtained indicated that yeast had "stringent control" of ribonucleic acid synthesis and that this control was reversed by cycloheximide only under glucose starvation or ammonia starvation in the presence of acetate as carbon source (phenotypic relaxation). Therefore, it appeared that the "phenotypic relaxation" of RNA synthesis depended on the carbon source present in the medium suggesting that the process could be negatively controlled by glucose or by some glucose catabolite(s). Such a phenotypic relaxation was sensitive to erythromycin treatment. On the other hand, total protein synthesis carried out during amino-acid starvation in the presence of glucose or ammonia starvation in the presence of acetate was 30%-40% inhibited by erythromycin, showing that in these conditions sensitivity to a non legitimate inhibitor could be triggered off in an haploid strain, and that such sensitivity did not depend on the presence of glucose in the medium.
D000596:Amino Acids / Q000502:physiology*; D003470:Culture Media; D003513:Cycloheximide / Q000494:pharmacology; D004917:Erythromycin / Q000494:pharmacology; D005656:Fungal Proteins / Q000096:biosynthesis*; D005947:Glucose / Q000502:physiology*; D007930:Leucine / Q000378:metabolism; D012331:RNA, Fungal / Q000096:biosynthesis*; D012441:Saccharomyces cerevisiae / Q000187:drug effects / Q000378:metabolism*
D000596:Amino Acids; D003470:Culture Media; D005656:Fungal Proteins; D012331:RNA, Fungal; D004917:Erythromycin; D003513:Cycloheximide; D007930:Leucine; D005947:Glucose