Question

what are micro-RNAs and what are their biological functions.How they are synthesized and provide an application of miRNA in human diseases and treatment?

Answer 1

Ans: mi-RNA ( Micro-RNA): It regulates gene expression and is found in all eukaryotic except for marine plants, algae, and fungi.

They regulate gene expression by base-pairing with certain mRNA.

By doing so, they can control the mRNA's stability and their efficiency of translation.

Hundreds of micro RNAs have been discovered yet.

BIOLOGICAL FUNCTION:

micro RNA has a significant role in the diverse process including cell proliferation, cell death, neuronal patterning, fat metabolism, hematopoietic differentiation, immunity, and many more.

SYNTHESIS OF mi- RNA: mi-RNA is a 21-25 nucleotide single-stranded RNA.

-It produced from hairpin shaped precursors. Then the transcript undergoes processing. Genes for mi-RNA are transcribed to a primary mi-RNA (pri-miRNA). The pre-miRNA undergo processing (within the nucleus). A pre-miRNA processed by DROSHA. DROSHA: It is a class 2 RNase III enzyme. Then the transport of pre-miRNA moves to the cytoplasm. This transportation is mediated by exportin- 5 (EXP-5). In the cytoplasm, further processed to become mature mi-RNAs. Maturity mechanism done by DICER. DICER is an RNase III type protein. After that, it loaded onto the ARGONAUTE (ago) protein. At last, it produces the effector RNA-induced Silencing Complex (RISC). An unknown Helicase help in the unwinding of the duplex. One strand of the duplex remains the mature mi-RNA on AGO. And passenger mi-RNA strand is degraded.

Application of mi-RNA in Diseases and their treatment:

The mi- RNA importance has been attached to biomedical research to treat various problems.

Misregulation of several mi-RNAs leads to the development of certain diseases in humans and other organisms.

Nowadays, mi-RNA replacement therapy help in diseases tissues to and attempt to restore normal proliferation, apoptosis, cell cycle, and other cellular functions, that is affected by misregulation of one or more mi-RNAs.

The inhibition of mi-RNA also helps in the treatment of disease. It can remove the block of expression of a therapeutic protein.

On the other hand, the administration of a mi-RNA mimetic can increase the endogenous mi-RNA population that suppressing a harmful gene.

mi-RNA is making its way in the pharmaceutical industry as a mi-RNA inhibitors and mi-RNA mimetics in diverse fields such as cancer, cardiovascular diseases, neurological disorders, and viral infections.

A mi- RNA -dependent post-transcriptional gene silencing process has been proven effective in humans at the cell culture level.

There are many novel mi-RNA targets drugs available for inflammatory diseases.

mi-RNA-based diagnostic kit for various diseases is developed.