Dissection of Pol II trigger loop function and Pol II activity-dependent control of start site selection in vivo.

ABSTRACT: Structural and biochemical studies have revealed the importance of a conserved, mobile domain of RNA Polymerase II (Pol II), the Trigger Loop (TL), in substrate selection and catalysis. The relative contributions of different residues within the TL to Pol II function and how Pol II activity defects correlate with gene expression alteration in vivo are unknown. Using Saccharomyces cerevisiae Pol II as a model, we uncover complex genetic relationships between mutated TL residues by combinatorial analysis of multiply substituted TL variants. We show that in vitro biochemical activity is highly predictive of in vivo transcription phenotypes, suggesting direct relationships between phenotypes and Pol II activity. Interestingly, while multiple TL residues function together to promote proper tran

SUBMITTER: Kaplan CD 

PROVIDER: S-EPMC3325174 | biostudies-literature | 2012

REPOSITORIES: biostudies-literature