Appears to be stable component of the Pol II(G) complex form of RNA polymerase II. Pol II synthesizes mRNA precursors and many functional non-coding RNAs and is the central component of the basal RNA polymerase II transcription machinery. May play a role in Mediator-dependent regulation of transcription activation. In vitro, acts as negative regulator of transcriptional activation; this repression is relieved by the Mediator complex, which restores Pol II(G) activator-dependent transcription to a level equivalent to that of Pol II (By similarity).
Subcellular locations: Nucleus