ROLE FOR THE AMINO-TERMINAL REGION OF HUMAN TBP IN U6 SNRNA TRANSCRIPTION

Basal transcription from the human RNA polymerase III U6 promoter depe nds on a TATA box that recruits the TATA box-binding protein (TBP) and a proximal sequence element that recruits the small nuclear RNA (snRN A)-activating protein complex (SNAP(c)). TBP consists of a conserved c arboxyl-terminal domain that performs all known functions of the prote in and a nonconserved amino-terminal region of unknown function. Here, the aminoterminal region is shown to down-regulate binding oi TBP to the U6 TATA box, mediate cooperative binding with SNAP(c) to the U6 pr omoter, and enhance U6 transcription.