Question

What is an Example of Protein involved in Positive Regulation?

Answer 1

For answering this question we should learn about the regulation of Gene Expression. Functioning of cells depends upon the environment the cells are in. Adaptation to a particular environment is done by regulating the expression of genes that encode the proteins and enzymes for survival in that particular environment. We will discuss more about gene expression in this question and understand its types and examples for getting the required answer.

Complete answer:
There are some factors which have influence on this process regulation which are Nutrients, Light, Temperature, Metals, Chemicals and signals coming from other cells. Malfunction in the regulation of gene expression can produce several diseases and disorders in the human body.
For positive regulation the binding of a particular protein or activator is necessary for transcription to begin. DNA bound activators can manage the transcription by helping with the ignition process, for doing this they sometimes tie RNA polymerase to the promoter.
An example of an activator is Catabolite activator protein or CAP. It is used in positive regulation of gene expression in Lac-Operon. It promotes the transcription of Lac-Operon and binds RNA to the promoter.
For Negative regulation the binding of a particular protein or repressor hinders the transcription. DNA bound repressors generally act to stop the tethering of RNA polymerase to the promoter or hinder the movement of RNA polymerase.
An example of a repressor is the Lac repressor that inhibits the transcription in regulation of gene expression in lac-operon.

Note:
A promoter is a DNA (Deoxyribonucleic acid) sequence which is required for turning a gene on or off. The process of transcription is initiated by the promoter. It has a binding site for enzymes which are used to make messenger RNA molecules.