Question

What is negative gene regulation?

Answer 1

• Control of an operon is a type of gene regulation that enables organisms to regulate the expression of various genes depending on environmental conditions.
• Operon regulation can be either positive or negative by induction or repression.
• Negative control involves the binding of a repressor to the operator to prevent transcription. If an inducer molecule is present, it binds to the repressor and changes its conformation so that it is unable to bind to the operator.
• Repressor proteins are produced by a regulator gene, but they are unable to bind to the operator in their normal conformation.
• Certain molecules called co-repressors are bound by the repressor proteins, causing a conformational change to the active site. The activated repressor protein binds to the operator and prevents transcription.
• For example, the tryptophan operator is involved in the synthesis of tryptophan. The tryptophan binds to the repressor protein and enables it to repress gene transcription.