Question

Is a promoter a part of an operon?

Answer 1

Operon:

1. Genetic regulatory system which is found commonly in prokaryotes like bacteria and also some viruses.
2. These are the functioning unit of DNA in which related genes are grouped together under the control of the promoter, which transcribes for single mRNA which will code for multiple proteins.

The general structure of operon:

Operon consists of 3 DNA components-

Promoter

1. It is a nucleotide sequence that allows the gene to be transcribed.
2. RNA polymerase recognizes the promoter, which then initiates transcription.
3. Promoters specify which genes should be used for messenger RNA formation and control the proteins the cell produces.

Operator

It is a repressor binding site in DNA. When repressor protein binds here it stalls the process of gene transcribing by RNA polymerase.

Structural genes

These are the genes co-regulated by operon.