Regulation of Gene Expression

Free online lectures on Medical Biochemistry for Medical and Allied Health Students by Biochemistry Club

Introduction

Gene expression is a multistep process that ultimately results in the production of a functional gene product, either RNA or a protein.

The first step in gene expression, transcription, is the primary site of regulation in both prokaryotes and eukaryotes.

In eukaryotes, gene expression also involves extensive post-transcriptional & post-translational processes.

There are also other actions that influence access to particular regions of the DNA.

Each of these steps can be regulated to provide additional control over the kinds and amounts of functional products that are produced.

Points to Note

ALL GENES ARE NOT REGULATED 

Constitutive genes encode products required for basic cellular functions and so are continually expressed – “housekeeping” genes.

Regulated genes are expressed only under certain conditions. They may be expressed in all cells or in only a subset of cells e.g. hepatocytes.

The ability to regulate gene expression i.e. to determine if, how much, and when particular gene products will be made, gives the cell control over structure & function.

It is the basis for cellular differentiation, morphogenesis, and adaptability of any organism.

Control of gene expression is best understood in prokaryotes.

But its main themes are repeated in eukaryotes.

FOR COMPLETE LESSON GO TO THE BIOCHEMISTRY II SECTION AND CLICK GENETICS, THEN CURRICULUM TO VIEW THE FULL LIST OF LESSONS.