The basic structure of a gene contains three regulatory regi

The basic structure of a gene contains three regulatory regions. Describe each of these three regions. Based on your description, predict what effect a change in the nucleotides of one of these regulatory regions might have on the expression of the gene?

Solution

The cheif regulatory regions of gene are Repressor, promoter and operator regions.

1. Repressor :  Repressor is a DNA- or RNA-binding protein that inhibits the expression of gene by binding to the operator. A DNA-binding repressor blocks the attachment of RNA polymerase to the promoter, thus preventing transcription of the genes into messenger RNA. This blocking of expression is called repression.

2. Promoter: Promoter is a region of DNA which initiates transcription of a particular gene. Promoters are located near the transcription same strand and upstream on the DNA.

3. Operator: Operator is a short region of DNA, which lies partially within the promoter and that interacts with a regulatory protein that controls the transcription of the operon.

A mutation in Operator region leads to continous expresson of genes.