TFIIH phosphorylation of the Pol II CTD stimulates mediator dissociation from the preinitiation complex and promoter escape.
Mol Cell
; 54(4): 601-12, 2014 May 22.
Article
in En
| MEDLINE
| ID: mdl-24746699
ABSTRACT
The transition between transcriptional initiation and elongation by RNA polymerase (Pol) II is associated with phosphorylation of its C-terminal tail (CTD). Depletion of Kin28, the TFIIH subunit that phosphorylates the CTD, does not affect elongation but causes Pol II occupancy profiles to shift upstream in a FACT-independent manner indicative of a defect in promoter escape. Stronger defects in promoter escape are linked to stronger effects on preinitiation complex formation and transcription, suggesting that impairment in promoter escape results in premature dissociation of general factors and Pol II near the promoter. Kin28 has a stronger effect on genes whose transcription is dependent on SAGA as opposed to TFIID. Strikingly, Kin28 depletion causes a dramatic increase in Mediator at the core promoter. These observations suggest that TFIIH phosphorylation of the CTD causes Mediator dissociation, thereby permitting rapid promoter escape of Pol II from the preinitiation complex.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Yeasts
/
RNA Polymerase II
/
Fungal Proteins
/
Promoter Regions, Genetic
/
Cyclin-Dependent Kinases
/
Transcription Factor TFIIH
Language:
En
Journal:
Mol Cell
Journal subject:
BIOLOGIA MOLECULAR
Year:
2014
Type:
Article
Affiliation country:
China