A new regulatory domain on the TATA-binding protein

Abstract
Recognition of the TATA box by the TATA‐binding protein (TBP) is a highly regulated step in RNA polymerase II‐dependent transcription. Several proteins have been proposed to regulate TBP activity, yet the TBP domains responsive to all these regulators have not been defined. Here we describe a new class of TBP mutants that increase transcription from core promoters in vivo. The majority of these mutations alter amino acids that cluster tightly on the TBP surface, defining a new TBP regulatory domain. The mutant TBP proteins are defective for binding the transcriptional regulator yNC2, are resistant to inhibition by yNC2 in vitro and exhibit allele‐specific genetic interactions with yNC2. These results provide strong biochemical and genetic evidence that TBP is directly repressed in vivo, and define a new TBP domain important for transcriptional regulation.