TATA box-binding protein-associated factor RNA polymerase I subunit A (TAF1A)

Part of the transcription factor SL1/TIF-IB complex, which is involved in the assembly of the PIC (pre- initiation complex) through RNA polymerase I-dependent transcription. The speed of PIC formation likely is primarily determined by the rate of association of SL1/TIF-IB with the rDNA promoter.

SL1/TIF-IB is involved in stabilization of nucleolar transcription factor 1/UBTF on rDNA. Formation of SL1/TIF-IB excludes the association of TBP with TFIID subunits.