BIOL3090 Lecture Notes - Lecture 13: Tata Box, Transcription Preinitiation Complex, Transcription Factor Ii A
Document Summary
Eukaryotes are weak at initiation transcription so they use gtfs. Dabpolf complex determined through a gel shift assay. Tfiif associates with pol ii, they come in and recognise tfiid and tfiib, and that"s the start of the pic. One of those domains (core) is the tbp (tata box binding protein). It has a series of other proteins known as tafs (tbp associated factors). The tbp binds to and twists the dna opens up. Tbp is important for pol ii driven transcription, as well as other polymerases. Tbp binds with taf 1 and 2 as well. Tfiid recognises dna even without a tata box recognises initiator and downstream proximal element (via taf 1 and 2). Not every gene has every element, so some don"t have a tata box. If it has a gc box sp1 recognises that (not a gtf), and it recognises taf 4. Once you get transcription it"s easier to reinitiate transcription.