BIOL 202 Lecture Notes - Lecture 27: Mutation, Tata Box, Histone H2A
Document Summary
Initiation: recruit of pol ii needs general transcription factors, bind to upstream core promoter, tbp and tfiid bind to tata box (-30 bp, recruits other tfs and poly ii, common tfs. Determine whether a tf is cis or trans acting. Promoter makes protein that is easy to measure it"s amount (level of gene expression) Mutation in promoter regions produce less than wild type expression: testing for presence of regulatory sequences. When the mutations are at the regulatory sites, relative transcription level decreases: tissue specific transcription factors. Direct interaction with activators/repressors etc. , or change chromatin structure. E. g. pax6 genes in mice (tissue specific enhancer: enhancer and silencers. Architectural proteins bend dna to bring enhancers close to transcription start site (sst) recruit cofactors (cbp) that help recruit tf and poly ii. Binds to upstream activator sequences (uas) of other gal genes (that are responsible for galactose-glucose transformation) Modular structure: activation domain, dna binding domain, dimerization domain.
