Saccharomyces cerevisiae RNA polymerase II is affected by Kluyveromyces lactis zymocin.

Abstract

The G(1) arrest imposed by Kluyveromyces lactis zymocin on Saccharomyces cerevisiae cells requires a functional RNA polymerase II (pol II) Elongator complex. In studying a link between zymocin and pol II, progressively truncating the carboxyl-terminal domain (CTD) of pol II was found to result in zymocin hypersensitivity as did mutations in four different CTD kinase genes. Consistent with the notion that Elongator preferentially associates with hyperphosphorylated (II0) rather than hypophosphorylated (IIA) pol II, the II0/IIA ratio was imbalanced toward II0 on zymocin treatment and suggests zymocin affects pol II function, presumably in an Elongator-dependent manner. As judged from chromatin immunoprecipitations, zymocin-arrested cells were affected with regards to pol II binding to the ADH1 promotor and pol II transcription of the ADH1 gene. Thus, zymocin may interfere with pol II recycling, a scenario assumed to lead to down-regulation of pol II transcription and eventually causing the observed G(1) arrest.

• Authors: Daniel Jablonowski, Raffael Schaffrath
• Journal: The Journal of biological chemistry (J Biol Chem) Vol. 277 Issue 29 Pg. 26276-80 (Jul 19 2002) ISSN: 0021-9258 [Print] United States
• PMID: 12015322 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Killer Factors, Yeast
• Mycotoxins
• zymocin
• RNA Polymerase II

Topics

• Down-Regulation
• G1 Phase
• Killer Factors, Yeast
• Kluyveromyces (metabolism)
• Mutation
• Mycotoxins (pharmacology)
• Phosphorylation
• RNA Polymerase II (genetics, metabolism)
• Saccharomyces cerevisiae (enzymology)
• Transcription, Genetic