General Transcription Factor IIIC, Polypeptide 3 (GTF3C3)

By screening human cDNA cell libraries using degenerate PCR primers corresponding to internal peptide sequences of the 102-kD subunit of GTF3C, Hsieh et al. (1999) obtained a cDNA encoding GTF3C3, which they called TFIIIC102. Sequence analysis showed that the deduced 886-amino acid GTF3C3 protein contains N-terminal basic and acidic regions, a central acidic region, a C-terminal helix-loop-helix region, and 11 tetratricopeptide repeats. Immunoblot analyses indicated that the expressed cDNA encodes a 102-kD protein that copurifies with the remainder of the GTF3C complex. In addition, the authors showed that the GTF3C complex interacts with GTF3B (TAF3C) in the recruitment of RNA polymerase III.