Transcription factors Specifity and transcriptional enhancement Transcription factors are proteins that bind to the enhancer or promoter regions and interact such that transcription occurs from only a small group of promoters in any cell. In addition other proteins bind to the tad which have a Histone acety lase activity Histon Acetyl Transferases( HAT) Figure Histone Ac Hyperacetylation Alters Nucleosomal Conformation a nucleosome hypoacetylated histones NAc (blue)is more stable than a nucleosome with acetylated histones (yellow Acetylation renders the histone tails (black more mobile AcTranscription factors are proteins that bind to the enhancer or promoter regions and interact such that transcription occurs from only a small group of promoters in any cell. In addition other proteins bind to the TAD which have a Histone Acetylase activity = Histon Acetyl Transferases ( HAT ) Transcription factors Specifity and transcriptional enhancement