Mediator-dependent recruitment of TFIIH modules in preinitiation complex.
In vitro, without Mediator, the association of general transcription factors (GTF) and RNA polymerase II (Pol II) in preinitiation complexes (PIC) occurs in an orderly fashion. In this work, we explore the in vivo function of Mediator in GTF recruitment to PIC. A direct interaction between Med11 Mediator head subunit and Rad3 TFIIH subunit was identified. We explored the significance of this interaction and those of Med11 with head module subunits Med17 and Med22 and found that impairing these interactions could differentially affect the recruitment of TFIIH, TFIIE, and Pol II in the PIC. A med11 mutation that altered promoter occupancy by the TFIIK kinase module of TFIIH genome-wide also reduced Pol II CTD serine 5 phosphorylation. We conclude that the Mediator head module plays a critical role in TFIIH and TFIIE recruitment to the PIC. We identify steps in PIC formation that suggest a branched assembly pathway.
Esnault
Cyril
C
CEA, iBiTec-S, F-91191 Gif-sur-Yvette cedex, France.
Ghavi-Helm
Yad
Y
Brun
Sylvain
S
Soutourina
Julie
J
Van Berkum
Nynke
N
Boschiero
Claire
C
Holstege
Frank
F
Werner
Michel
M
D002503:Centromere / Q000378:metabolism; D047369:Chromatin Immunoprecipitation; D004265:DNA Helicases / Q000378:metabolism; D015966:Gene Expression Regulation, Fungal; D016681:Genome, Fungal / Q000235:genetics; D056892:Mediator Complex; D008954:Models, Biological; D009154:Mutation / Q000235:genetics; D010766:Phosphorylation; D010770:Phosphotransferases / Q000378:metabolism; D011401:Promoter Regions, Genetic / Q000235:genetics; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D021122:Protein Subunits / Q000378:metabolism; D012319:RNA Polymerase II / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics*; D029701:Saccharomyces cerevisiae Proteins / Q000378:metabolism*; D051758:Transcription Factor TFIIH / Q000378:metabolism*; D019473:Transcription Factors, TFII / Q000378:metabolism; D014158:Transcription, Genetic
C531156:Med11 protein, S cerevisiae; D056892:Mediator Complex; D021122:Protein Subunits; D012333:RNA, Messenger; D029701:Saccharomyces cerevisiae Proteins; D019473:Transcription Factors, TFII; C066644:transcription factor TFIIE; D051758:Transcription Factor TFIIH; D010770:Phosphotransferases; D012319:RNA Polymerase II; C061897:Rad3 protein, S cerevisiae; D004265:DNA Helicases