Amino acid signaling in yeast: post-genome duplication divergence of the Stp1 and Stp2 transcription factors.

ABSTRACT: When yeast cells detect external amino acids via their permease-like Ssy1 sensor, the cytosolic precursor forms of Stp1 and Stp2 transcription factors are activated by endoproteolytic removal of their N-terminal domains, a reaction catalyzed by the Ssy5 endoprotease. The processed Stp factors then migrate into the nucleus, where they activate transcription of several amino acid permease genes including AGP1. We report here that the STP1 and STP2 genes most likely derive from the whole genome duplication that occurred in a yeast ancestor. Although Stp1 and Stp2 have been considered redundant, we provide evidence that they functionally diverged during evolution. Stp2 is the only factor processed when amino acids are present at low concentration, and the transcriptional activation of AGP1 pro

SUBMITTER: Wielemans K 

PROVIDER: S-EPMC2801287 | biostudies-literature | 2010 Jan

REPOSITORIES: biostudies-literature