Regulator Gene in Operon Model

The operon model is a genetic regulatory mechanism in prokaryotic organisms that controls the expression of genes involved in metabolic pathways. The operon consists of a regulatory gene, promoter, operator, and structural genes. The regulatory gene codes for the production of a protein that controls the transcription of the structural genes.

Function of Regulator Gene in Operon Model

The regulator gene in the operon model functions as a repressor. It produces a repressor protein that binds to the operator region in the DNA, blocking the RNA polymerase from transcribing the structural genes. The repressor protein is synthesized in an inactive form, which requires a corepressor molecule to activate it.

When the corepressor molecule binds to the repressor protein, it undergoes a conformational change, allowing it to bind to the operator region in the DNA. This blocks the RNA polymerase from binding to the promoter region, preventing the transcription of the structural genes.

In the absence of the corepressor molecule, the repressor protein remains inactive, allowing the RNA polymerase to bind to the promoter region and transcribe the structural genes. This results in the production of enzymes involved in metabolic pathways.

Conclusion

In summary, the regulator gene in the operon model functions as a repressor by producing a repressor protein that binds to the operator region in the DNA, blocking the transcription of the structural genes. It requires a corepressor molecule to activate it, which allows it to bind to the operator region in the DNA. In the absence of the corepressor molecule, the repressor protein remains inactive, allowing the transcription of the structural genes.

In operon model , i regulator gene forms a active repressor which binds with operator