1. PROKARYOTE GENE REGULATION transcriptional control post-transcriptional control post-translational control REGULATION OF TRANSCRIPTION Negative Positive SBI 4U Panayiotou

2. GENE PiPi LacICAPP lac OLacZLacYLacA LacZ: ß-galactosidase LacY: lactose permease Lac A: thiogalactoside transacetylase LacI: lac repressor protein CAP: unwinding site P: promotor regions O: Operator TRANSCRIPTION OF OPERON AND REGULATORY PROTEIN RNA polymerase PiPi LacICAPP lac OLacZLacYLacA Z YA mRNA Regulatory protein SBI 4U Panayiotou

3. REGULATORY PROTEIN IN ACTION PiPi LacICAPP lac OLacZLacYLacA RNA polymerase CONTROLLING REGULATORY PROTEIN A. BY LACTOSE lactose PiPi LacICAPP lac OLacZLacYLacA RNA polymerase SBI 4U Panayiotou

4. B. BY cAMP PiPi LacICAPP lac OLacZLacYLacA CAP cAMP RNA polymerase TRANSCRIPTION OR NO TRANSCRIPTION…. That is the question. SBI 4U Panayiotou

5. SBI 4U Panayiotou TRANSCRIPTION OF TRP GENE PO tryp Etryp Atryp Btryp Ctryp D RNA polymerase mRNA PO tryp Etryp Atryp Btryp Ctryp D REGULATION Regulatory protein tryptophan RNA polymerase

6. GENE REGULATION IN EUKARYOTES SBI 4U Panayiotou pre-transcriptional control transcriptional control post-transcriptional control translational control post-translational control