BI226 Lecture Notes - Lecture 10: Dna-Binding Domain, Lac Operon, Regulatory Sequence
Document Summary
Transcriptional control of gene expression: requires dna-protein interaction, certain bacterial genes need continuous function so they undergo what is called constitutive transcription. Some genes are only needed depending on environmental conditions so they are under regulated transcription: this includes control of initiation and amount of transcription. Gene regulation in bacteria interactions between binding proteins in dna and dna regulatory sequences also requires post-transcriptional regulation. Binds to repressor protein to prevent transcription: regulatory proteins binding to sequences like operators. Activated or inactivated by interacting with other compounds. Active sites: have two, dna binding domain. Where they bind to dna sequence: allosteric domain. Binds to molecule or protein called a corepressor causing a conformation change in both the protein and the dna binding. Domain, so it can no longer bind to dna inhibiting transcription. This is called allostery which can activate or inactivate transcription. Bind to activator binding sites which facilitate rna polymerase binding and the promotor to initiate transcription.
