BIOL308 Lecture Notes - Lecture 8: Creb, Creb-Binding Protein, Retinoid X Receptor
14 Feb 2018
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Document Summary
Describe the role of histone acetylation/deacetylation in regulation of transcription. Deacetylation: associated with repression of gene activity, deacetylases are present in co-repressor complexes. Acetylation: catalyzed by histone acetyltransferases, also called histone acetylases (hats, activates gene expression, coactivators (or coactivator complexes) often have hat activity. Describe an influence of activators and repressors on assembly of initiation complexes. In general: some tfs interact with each other (or ligands or both); those interactions promote or prevent binding of. Interactions with ligands: ligand binding domains in some tfs are responsible for both activation and inhibition switch on and off depending on if ligand is bound or not, which changes tfs conformation. Example: retinoic acid receptor (rar) + retinoid x receptor (rxr) heterodimer (rar-rxr); depending on ra being bound to it or not, it can activate or repress transcription through binding to different protein complexes (co-activator and co-repressor complex respectively)
