TFIIH's role in RNA Polymerase II releasal: recent article vs. course book

[Genecks]

Does TFIIH not play a major role in the releasal of RNA polymerase II to conduct transcription? Because I'm reading a book that's saying this:

 

A key ste in this release is the addition of phosphate groups to the 'tail' of RNA polymerase, an act performed by the general transcription factor TFIIH, which contains a protein kinase enzyme as one of its subunits... This phosphorylation is thought to help the polymerase disengage from the cluster of transcription factors, allowing transcription to commence. ONce transcription has begun, most of the 'GTFs' are released from the DNA so that they are available to initiation another round of transcription with a new RNA polymerase molecule.

 

Is this article contradicting that information?

 

Title:

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

 

<Published online before print August 7, 2009>

 

- http://www.pnas.org/content/early/2009/08/06/0903642106.abstract

 

1. Sun Woo Honga,b,

2. Seong Min Honga,

3. Jae Wook Yooa,b,

4. Young Chul Leec,

5. Soyoun Kimd,

6. John T. Lise and

7. Dong-ki Leea,b,1

 

Abstract

 

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.

Edited January 24, 2010 by Genecks

[dttom]

Yes, contradiction in budding yeast, but it remains as an open question, the mainstream is still a significant role of TFIIH in release of TFs in close-promotor initiation complex.