Involved in pre-mRNA splicing. Involved in nuclear mRNA decay. Initially thought to play a role in transcriptional coactivation through its association with the TRAP complex; however, it is not regarded as a stable Mediator complex subunit. May play a role in the positive regulation of the circadian clock. Associated with the large multiprotein complex TRAP (Mediator complex-like). Belongs to the BCLAF1/THRAP3 family.