Lecture : Lecture 14 Gene Regulation

• School: University of Maine
• Department: Micro and Molecular Biology
• Course: BMB 240
• Professor: Catherine Hopper

Document Summary

Lecture 14 gene regulation: gene regulation, review, types of gene expression, constitutive expression. Not regulated, always on: regulated gene expresseion. Regulated by an operon: control of transcription operons. Binding of activator protein to activator binding site. Bacteria controlled at transcription level: negative control of transcription and regulation of the operon, the operon on dna, regulator gene, promoter, operon, structural gene. Regulator gene- codes for regulatory protein (repressor), binds to operator site on dna and blocks transcription. Structural genes- codes for peptide (protein/enzyme: the lac operon - example of inducible genes. Controls genes that code for enzymes that catabolize lactose. Structure: function of the enzymes coded for on the lac operon. Allolactose is inducer: when are inducible genes off? when the inducer is absent (no lactose means no galolactase means no allolactose) Inducer must be present (needs to be lactose) Allolactose binds to repressor, preventing it from binding to the operator.