Davidson Missouri W/PLac

Background

pLac in a natural environment transcribes three adjacent genes which add up to approximately 5000nt. pLac is stimulated by a metabolite of lactose: allolactose (or an analog of allolactose: IPTG). IPTG induces transcription by binding to LacI. LacI binds to the one of three lac operators (o1) which is located near the start of transcription and overlaps into RNAP's interaction site at the -10 pribnow box. Several other factors of control of the lac operon have been identified such as the system's reliance on the cAMP-CAP complex, and repression by DNA looping between operator sequences.