The PAF1 complex is a multifunctional complex. Involved in transcription initiation via genetic interactions with TATA-binding proteins. Involved in elongation. Also has a role in transcription-coupled histone modification. Important for TATA site selection by TBP. Directly or indirectly regulates the DNA-binding properties of the TATA box-binding protein, and the relative activities of different TATA elements (By similarity). Component of the PAF1 complex.