operator region การใช้

• Under normal conditions, LexA binds to a 20-bp consensus sequence ( the SOS box ) in the operator region for those genes.
• It consists of two structural genes guaB ( encodes for IMP dehydrogenase or IMPDH ) and guaA ( encodes for GMP synthetase ) apart from the operator region.
• Lac Repressor ) closer to the DNA to increase their attraction and enable them to bind, as well as steric effect which exclude the Crowder proteins from this region ( Lac operator region ).
• Then, Phospho-AI-2 binds the transcriptional repressor protein, LsrR, which subsequently is released from the promoter / operator region of the lsr operon  and transcription of the " lsr " genes is initiated.