title: Relative levels of RNA polII subunits differentially affect starvation response in budding yeast.
abstract: The Rpb4/7 subcomplex of RNA polymerase II in Saccharomyces cerevisiae is known to play an important role in stress response and stress survival. These two proteins perform overlapping functions ensuring an appropriate cellular response through transcriptional regulation of gene expression. Rpb4 and Rpb7 also perform many cellular functions either together or independent of one another. Here, we show that Rpb4 and Rpb7 differently affect during the nutritional starvation response pathways of sporulation and pseudohyphae formation. Rpb4 enhances the cells' proficiency to sporulate but suppresses pseudohyphal growth. On the other hand, Rpb7 promotes pseudohyphal growth and suppresses sporulation in a dose-dependent manner. We present a model whereby the stoichiometry of Rpb4 and Rpb7 and their relative levels in the cell play a switch like role in establishing either sporulation or pseudohyphal gene expression.
authors.affiliation: Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore 12, India.
authors.forename: Sunanda R
authors.initials: SR
authors.lastname: Singh
authors.forename: Beena
authors.initials: B
authors.lastname: Pillai
authors.forename: Bindu
authors.initials: B
authors.lastname: Balakrishnan
authors.forename: Aruna
authors.initials: A
authors.lastname: Naorem
authors.forename: Parag P
authors.initials: PP
authors.lastname: Sadhale
mesh_terms: D000596:Amino Acids / Q000494:pharmacology; D015153:Blotting, Western; D005690:Galactose / Q000494:pharmacology; D005947:Glucose / Q000494:pharmacology; D009154:Mutation; D010957:Plasmids / Q000235:genetics; D012319:RNA Polymerase II / Q000235:genetics / Q000378:metabolism*; D012331:RNA, Fungal / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism*; D004718:Saccharomycetales / Q000201:enzymology / Q000235:genetics / Q000502:physiology*; D013172:Spores, Fungal / Q000187:drug effects / Q000235:genetics / Q000254:growth & development; D014170:Transformation, Genetic
chemical_list: D000596:Amino Acids; D012331:RNA, Fungal; D029701:Saccharomyces cerevisiae Proteins; D012319:RNA Polymerase II; C423309:RPB4 protein, S cerevisiae; C470553:RPB7 protein, S cerevisiae; D005947:Glucose; D005690:Galactose