The Pol II preinitiation complex (PIC) influences Mediator binding but not promoter-enhancer looping.
Genes Dev
; 35(15-16): 1175-1189, 2021 08 01.
Article
em En
| MEDLINE
| ID: mdl-34301767
ABSTRACT
Knowledge of how Mediator and TFIID cross-talk contributes to promoter-enhancer (P-E) communication is important for elucidating the mechanism of enhancer function. We conducted an shRNA knockdown screen in murine embryonic stem cells to identify the functional overlap between Mediator and TFIID subunits on gene expression. Auxin-inducible degrons were constructed for TAF12 and MED4, the subunits eliciting the greatest overlap. Degradation of TAF12 led to a dramatic genome-wide decrease in gene expression accompanied by destruction of TFIID, loss of Pol II preinitiation complex (PIC) at promoters, and significantly decreased Mediator binding to promoters and enhancers. Interestingly, loss of the PIC elicited only a mild effect on P-E looping by promoter capture Hi-C (PCHi-C). Degradation of MED4 had a minor effect on Mediator integrity but led to a consistent twofold loss in gene expression, decreased binding of Pol II to Mediator, and decreased recruitment of Pol II to the promoters, but had no effect on the other PIC components. PCHi-C revealed no consistent effect of MED4 degradation on P-E looping. Collectively, our data show that TAF12 and MED4 contribute mechanistically in different ways to P-E communication but neither factor appears to directly control P-E looping, thereby dissociating P-E communication from physical looping.
Palavras-chave
Texto completo:
1
Bases de dados:
MEDLINE
Assunto principal:
RNA Polimerase II
/
Fator de Transcrição TFIID
Tipo de estudo:
Prognostic_studies
Limite:
Animals
Idioma:
En
Revista:
Genes Dev
Assunto da revista:
BIOLOGIA MOLECULAR
Ano de publicação:
2021
Tipo de documento:
Article
País de afiliação:
Estados Unidos