repressor gene
The lac genes in E. coli are regulated by the lac operon, which is controlled by a repressor protein. The repressor binds to the operator region of the DNA, blocking the transcription of the lac genes. When lactose is present, it binds to the repressor, causing a conformational change that releases the repressor from the operator, allowing for the expression of the lac genes.
When lactose is present, it binds to the repressor protein, causing a conformational change that prevents the repressor from binding to the operator region of the lac operon. As a result, RNA polymerase can transcribe the structural genes of the lac operon, leading to the production of enzymes involved in lactose metabolism.
The lac operon is a group of genes involved in metabolizing lactose. The protein Lac repressor binds to the operator site in the absence of lactose, blocking gene expression. When lactose is present, it binds to the Lac repressor, causing it to release from the operator and allowing transcription of the genes involved in lactose metabolism.
The operator locus of a Lac operon functions as a binding site for the Lac repressor protein. This repressor protein binds to the operator in the absence of lactose, effectively blocking RNA polymerase from transcribing the genes responsible for lactose metabolism. When lactose is present, it binds to the Lac repressor, causing it to release from the operator, allowing RNA polymerase to transcribe the genes.
The regulator
Transcription of lactose-metabolizing genes is blocked when the Lac repressor protein binds to the operator region of the lac operon. This typically occurs in the presence of glucose when lactose is absent or in low concentrations. The Lac repressor prevents RNA polymerase from transcribing the genes, leading to inhibition of lactose metabolism.
The presence of lactose in the environment causes the lac operon to turn on. When lactose is present, it binds to the repressor protein, causing it to release from the operator region of the lac operon, allowing RNA polymerase to transcribe the genes needed for lactose metabolism.
Yes. A precursor to lactose binds to the repressor and prevents or relaxes its binding to the Lac operon.
The lac operon is shut off when lactose is absent. In the absence of lactose, the repressor protein binds to the operator site, preventing transcription of the lac operon genes.
The lac repressor can be likened to a security guard at a gate. When lactose is not present, the lac repressor binds to the operator region of the lac operon, preventing RNA polymerase from transcribing genes for lactose metabolism. Just like how the security guard restricts entry to unauthorized individuals, the lac repressor restricts gene expression in the absence of lactose.
I assume you mean the lac operon. The repressor binds upstream of the gene(s) in the regulatory gene region.