Phosphorylation of the RNA polymerase II C-terminal domain by TFIIH kinase is not essential for transcription of Saccharomyces cerevisiae genome

Proc Natl Acad Sci U S A. 2009 Aug 25;106(34):14276-80. doi: 10.1073/pnas.0903642106. Epub 2009 Aug 7.


Ser-5 phosphorylation of the RNA polymerase II (Pol II) C-terminal domain by TFIIH kinase has been implicated in critical steps in mRNA synthesis, such as Pol II promoter escape and mRNA 5'-capping. However, the general requirement and precise role of TFIIH kinase in Pol II transcription still remain elusive. Here we use a chemical genetics approach to show that, for a majority of budding-yeast genes, specific inhibition of the yeast TFIIH kinase results in a dramatic reduction in both mRNA level and Ser-5 C-terminal domain phosphorylation. Surprisingly, inhibition of TFIIH kinase activity only partially affected both Pol II density and Ser-2 phosphorylation level. The discrepancy between mRNA level and Pol II density is attributed to the defective 5'-capping, which results in the destabilization of mRNAs. Therefore, contrary to the current belief, our study points strongly toward a minor role of TFIIH kinase in Pol II transcription, and a more significant role in mRNA capping in budding yeast.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Actins / genetics
  • Binding Sites
  • Chromatin Immunoprecipitation
  • Cyclin-Dependent Kinases / antagonists & inhibitors
  • Cyclin-Dependent Kinases / genetics
  • Cyclin-Dependent Kinases / metabolism*
  • Enzyme Inhibitors / pharmacology
  • Exoribonucleases / genetics
  • Gene Expression Profiling
  • Gene Expression Regulation, Fungal / drug effects
  • Genome, Fungal*
  • Glucose Transport Proteins, Facilitative / genetics
  • Mutation
  • Nucleotidyltransferases / genetics
  • Nucleotidyltransferases / metabolism
  • Oligonucleotide Array Sequence Analysis
  • Phosphorylation
  • Promoter Regions, Genetic / genetics
  • Protein Binding
  • RNA Polymerase II / genetics
  • RNA Polymerase II / metabolism*
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • Reverse Transcriptase Polymerase Chain Reaction
  • Saccharomyces cerevisiae / genetics
  • Saccharomyces cerevisiae / metabolism*
  • Saccharomyces cerevisiae Proteins / antagonists & inhibitors
  • Saccharomyces cerevisiae Proteins / genetics
  • Saccharomyces cerevisiae Proteins / metabolism*
  • Transcription, Genetic*


  • Act1 protein, S cerevisiae
  • Actins
  • Enzyme Inhibitors
  • Glucose Transport Proteins, Facilitative
  • HXT1 protein, S cerevisiae
  • RNA, Messenger
  • Saccharomyces cerevisiae Proteins
  • Cyclin-Dependent Kinases
  • Kin28 protein kinase, S cerevisiae
  • Nucleotidyltransferases
  • RNA Polymerase II
  • mRNA guanylyltransferase
  • Exoribonucleases
  • XRN1 protein, S cerevisiae