Relative levels of RNA polII subunits differentially affect starvation response in budding yeast

• Published in: Biochemical and biophysical research communications 2007-04, Vol.356 (1), p.266-272
• Main Authors: Singh, Sunanda R., Pillai, Beena, Balakrishnan, Bindu, Naorem, Aruna, Sadhale, Parag P.
• Format: Article
• Language: English
• Subjects: Amino Acids - pharmacology; Blotting, Western; Galactose - pharmacology; Glucose - pharmacology; Mutation; Plasmids - genetics; Pseudohyphal growth; Reverse Transcriptase Polymerase Chain Reaction; RNA polII; RNA Polymerase II - genetics; RNA Polymerase II - metabolism; RNA, Fungal - genetics; RNA, Fungal - metabolism; Rpb4; Rpb7; Saccharomyces cerevisiae; Saccharomyces cerevisiae Proteins - genetics; Saccharomyces cerevisiae Proteins - metabolism; Saccharomycetales - enzymology; Saccharomycetales - genetics; Saccharomycetales - physiology; Spores, Fungal - drug effects; Spores, Fungal - genetics; Spores, Fungal - growth & development; Sporulation; Stress response; Transformation, Genetic
• ISSN: 0006-291X; 1090-2104
• DOI: 10.1016/j.bbrc.2007.02.120

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.