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Artificial RNA Polymerase II Elongation Complexes for Dissecting Co-transcriptional RNA Processing Events
Published on: May 13, 2019
Genetic interactions between the ESS1 prolyl-isomerase and the RSP5 ubiquitin ligase reveal opposing effects on RNA
1Wadsworth Center, New York State Department of Health & Department of Biomedical Sciences, School of Public Health, State University of New York at Albany, 12208, USA.
Current Genetics
|January 25, 2002
Summary
The prolyl-isomerase Ess1 and ubiquitin ligase Rsp5 regulate RNA polymerase II (pol II) transcription by opposingly interacting with the pol II CTD. Their genetic interaction via RPB1 suggests a coordinated control mechanism for pol II availability.
Area of Science:
- Molecular Biology
- Gene Regulation
- Protein Biochemistry
Background:
- RNA polymerase II (pol II) transcription involves dynamic protein complex assembly on the pol II C-terminal domain (CTD).
- Ess1 (prolyl-isomerase) and Rsp5 (ubiquitin ligase) are implicated in regulating pol II CTD interactions.
- Ess1 is proposed to positively regulate transcription, while Rsp5 is suggested to negatively regulate it via RPB1 ubiquitination and degradation.
Purpose of the Study:
- To investigate the functional relationship between Ess1 and Rsp5 in pol II transcription.
- To elucidate the role of RPB1 in the genetic interaction between ESS1 and RSP5.
- To determine if Ess1 and Rsp5 directly compete for binding to the pol II CTD.
Main Methods:
- Genetic interaction analysis, including assessing growth defects and plasmid toxicity.
- Over-expression studies of RSP5 and RPB1 in ess1ts mutant cells.
- Modified two-hybrid assays to assess protein-protein interactions with the CTD.
Main Results:
- ESS1 and RSP5 exhibit a genetic interaction that is dependent on RPB1.
- RSP5 over-expression exacerbates ess1ts growth defects, an effect rescued by RPB1 over-expression.
- Ess1 and Rsp5 were shown to directly compete for binding to the pol II CTD.
Conclusions:
- Ess1 and Rsp5 function antagonistically to regulate pol II transcription.
- The interaction between Ess1, Rsp5, and RPB1 is critical for controlling pol II levels.
- This study proposes a model where Ess1 and Rsp5 mediate opposing regulatory effects on pol II function through CTD interactions.
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