The regulator
Repressor
A repressor protein binds to the operator region of DNA to inhibit the binding of RNA polymerase, blocking transcription of the gene. This mechanism is common in prokaryotic organisms to regulate gene expression by preventing transcription of specific genes when they are not needed.
The expression of the tryptophan operon is controlled by a repressor protein that binds to the operator region in the presence of tryptophan. When tryptophan levels are high, the repressor is active and prevents transcription of the operon. When tryptophan levels are low, the repressor is inactive, allowing transcription to occur.
The inducer.
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 tryptophan operon is turned off in the presence of tryptophan because tryptophan acts as a corepressor. When tryptophan levels are high, it binds to the trp repressor protein. This trp-repressor complex then binds to the operator region of the operon, preventing RNA polymerase from transcribing the genes involved in tryptophan synthesis.
Function as a corepressor that binds to the repressor protein and activates it to bind to the operator region of the operon. This binding prevents RNA polymerase from transcribing the operon genes, leading to the downregulation of gene expression.
Yes. A precursor to lactose binds to the repressor and prevents or relaxes its binding to the Lac operon.
An aporepressor is a repressor which binds with a corepressor.
The other region is the OPERATOR (O) e coli cells contains several copies of a DNA binding proteins known as the lac repressor, which can be bind to the O region your answer: Operator
It binds to the operator.
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.