Question

What is an operon?

Answer 1

Hint: In microscopic organisms, related genes are frequently found in a group on the chromosome, where they undergo transcription from one promoter (RNA polymerase binding site) as a solitary unit. Such a group of genes under control of one promoter is known as an operon. Operons are regular in microbes, yet they are uncommon in eukaryotes, for example, humans.

Complete Answer:
- Operons are regions of DNA that are made of a group of related genes. They consist of a promoter region, an operator, and multiple related genes.
- Operons are available in prokaryotes (microbes and archaea), however are missing in eukaryotes.
- Operons were first recognized as a method of gene expression control in 1961 by François Jacob and Jacques Monod. The operator is present either within the promoter or between the promoter and the genes.
- The location of the operator i.e. the place where it is present decides its regulation i.e. it either allows or prevents transcription of the genes into mRNA.
- Operons can be under negative or positive control. Negative control includes turning off the operon within the sight of a repressor; this can be either repressible or inducible. A repressible operon is one that is for the most part on yet which can be repressed in the presence of a repressor.
- An inducible operon is one that is ordinarily off. Without an inducer the operator is obstructed by a repressor. At the point when the inducer is available it interacts with the repressor protein, delivering it from the operator and permitting transcription to continue. Positive control of an operon is when gene expression is aggregated in the presence of a regulatory protein.

Note: Operon which is genetic regulatory system coding allows protein synthesis to be controlled coordinately according to the requirements of the cell.