TY - JOUR
T1 - Tail and Kinase Modules Differently Regulate Core Mediator Recruitment and Function In Vivo
AU - Jeronimo, Célia
AU - Langelier, Marie France
AU - Bataille, Alain R.
AU - Pascal, John M.
AU - Pugh, B. Franklin
AU - Robert, François
N1 - Publisher Copyright:
© 2016 Elsevier Inc.
PY - 2016/11/3
Y1 - 2016/11/3
N2 - Mediator is a highly conserved transcriptional coactivator organized into four modules, namely Tail, Middle, Head, and Kinase (CKM). Previous work suggests regulatory roles for Tail and CKM, but an integrated model for these activities is lacking. Here, we analyzed the genome-wide distribution of Mediator subunits in wild-type and mutant yeast cells in which RNA polymerase II promoter escape is blocked, allowing detection of transient Mediator forms. We found that although all modules are recruited to upstream activated regions (UAS), assembly of Mediator within the pre-initiation complex is accompanied by the release of CKM. Interestingly, our data show that CKM regulates Mediator-UAS interaction rather than Mediator-promoter association. In addition, although Tail is required for Mediator recruitment to UAS, Tailless Mediator nevertheless interacts with core promoters. Collectively, our data suggest that the essential function of Mediator is mediated by Head and Middle at core promoters, while Tail and CKM play regulatory roles.
AB - Mediator is a highly conserved transcriptional coactivator organized into four modules, namely Tail, Middle, Head, and Kinase (CKM). Previous work suggests regulatory roles for Tail and CKM, but an integrated model for these activities is lacking. Here, we analyzed the genome-wide distribution of Mediator subunits in wild-type and mutant yeast cells in which RNA polymerase II promoter escape is blocked, allowing detection of transient Mediator forms. We found that although all modules are recruited to upstream activated regions (UAS), assembly of Mediator within the pre-initiation complex is accompanied by the release of CKM. Interestingly, our data show that CKM regulates Mediator-UAS interaction rather than Mediator-promoter association. In addition, although Tail is required for Mediator recruitment to UAS, Tailless Mediator nevertheless interacts with core promoters. Collectively, our data suggest that the essential function of Mediator is mediated by Head and Middle at core promoters, while Tail and CKM play regulatory roles.
UR - http://www.scopus.com/inward/record.url?scp=84995476616&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84995476616&partnerID=8YFLogxK
U2 - 10.1016/j.molcel.2016.09.002
DO - 10.1016/j.molcel.2016.09.002
M3 - Article
C2 - 27773677
AN - SCOPUS:84995476616
SN - 1097-2765
VL - 64
SP - 455
EP - 466
JO - Molecular cell
JF - Molecular cell
IS - 3
ER -