Transcription factors tfs - Study guides, Class notes & Summaries

5. Compare and contrast the functions of bacterial sigma factor and eukaryotic TFIID. What properties and functions do they have in common? How do they differ? Solution Prokaryotic sigma factors confer specific promoter recognition to RNAP via Sigma subunit 1.1, which acts as a DNA 'mimic' - occupying the downstream DNA binding site. This interaction is displaced only when the promoter region is bound, hence conferring the specificity. Note that Sigma factor on its own cannot ...