Question

Describe several ways in which post-transcriptional regulation can occur

Answer 1

Post-transcriptional regulation is a method by which the expression of a gene is controlled at the RNA level. It is the regulation that takes place after transcription and before translation.

Methods of post-transcriptional regulation are:-

1) 5' capping - it is done to protect the mRNA from exonuclease. In it, 5' end changes to 3' end by 5'-5' linkage.

2) 3' polyadenylation- In it, a piece of RNA made up of only adenine base is added to the 3' end which protects it from 3' exonuclease and increases translation.

3) Splicing- It is the process by which introns, the noncoding regions of genes, are removed out of the primary messenger RNA transcript, and the exons (i.e., coding regions) are joined together in order to make the mRNA able to create proteins.

4) RNA editing- It is the process in which there is sequence variation in the RNA molecule takes place and is catalyzed by enzymes.

5) Manipulation of mRNA stability to control its half-life. mRNA can have a half-life of a day or more which allows for the production of more protein products. Therfore unstable mRNA is used in regulation that must occur quickly.