Mediator dynamics during heat shock in budding yeast.

The Mediator complex is central to transcription by RNA polymerase II (Pol II) in eukaryotes. In budding yeast (), Mediator is recruited by activators and associates with core promoter regions, where it facilitates preinitiation complex (PIC) assembly, only transiently before Pol II escape. Interruption of the transcription cycle by inactivation or depletion of Kin28 inhibits Pol II escape and stabilizes this association.