Transcription factors for genes that are transcribed by RNA polymerase III. The initiation complexes are multisubunit and are assembled in a stepwise fashion. TFIIIC, itself a multisubunit complex, binds to promoters of tRNA genes and mediates binding of TFIIIB, which consists of three polypeptides including the TATA-binding protein, and TFIIIB recruits polymerase III. TFIIIA is a single-subunit protein that binds the promoters of the 5S RNA genes and, having done so, forms a complex with TFIIIC, which can then interact with TFIIIB and polymerase as with the tRNA initiation complex.
Subjects: Medicine and Health — Chemistry.