InterPro domain: IPR033599

Rrn7 is a subunit of the yeast Pol I core factor. It associates strongly with both Rrn6 and Rrn11 to form a complex which itself binds the TATA-binding protein, and is required for transcription by the core domain of the RNA Pol I promoter [ 1 , 2 ].

Rrn7 human orthologue, TATA box-binding protein-associated factor RNA polymerase I subunit B (TAF1B), is also a component of RNA polymerase I core factor complex. It acts as a GTF2B/TFIIB-like factor and plays a key role in multiple steps during transcription initiation [ 3 ]. Both Rrn7 and TAF1B are TFIIB-like factors. Although distantly related, they share many activities associated with TFIIB-like factors [ 4 ].

1. RRN6 and RRN7 encode subunits of a multiprotein complex essential for the initiation of rDNA transcription by RNA polymerase I in Saccharomyces cerevisiae. Genes Dev. 8, 2349-62
2. A novel 66-kilodalton protein complexes with Rrn6, Rrn7, and TATA-binding protein to promote polymerase I transcription initiation in Saccharomyces cerevisiae. Mol. Cell. Biol. 16, 6436-43
3. TAF1B is a TFIIB-like component of the basal transcription machinery for RNA polymerase I. Science 333, 1640-2
4. Yeast Rrn7 and human TAF1B are TFIIB-related RNA polymerase I general transcription factors. Science 333, 1637-40