This family represents a domain of unknown function located between the Transcription factor IIIC subunit delta N-term (Pfam:PF12657) and the Putative zinc-finger of transcription factor IIIC complex (Pfam:PF12660) within the transcription Factor IIIC 90 kDa subunit (TFIIIC-delta/TFIIIC90, also known as general transcription factor 3C polypeptide 4). TFIIIC is a multisubunit complex that directly recognises promoter elements and recruits TFIIIB and RNA polymerase III, being absolutely required for RNA polymerase III transcription. TFIIIC90 has an intrinsic histone acetyltransferase activity with a substrate specificity for histone H3 [1]. This domain is likely to be involved in the interaction with other components of the TFIIIC complex.

1: The TFIIIC90 subunit of TFIIIC interacts with multiple components of the RNA polymerase III machinery and contains a histone-specific acetyltransferase activity. Hsieh YJ, Kundu TK, Wang Z, Kovelman R, Roeder RG; Mol Cell Biol. 1999;19:7697-7704. PMID:10523658