What are the different kinds of RNAs and what do they do?

RNA is a polymeric molecule that can be classified into various groups based on their functions. The major types of RNA are as follows:

• Messenger RNA (mRNA) is the RNA that carries genetic information from DNA and serves as the blueprints from protein production
• Ribosomal RNA (rRNA) is the catalytic component of the ribosomes, where protein synthesis takes place.
• Transfer RNA (tRNA) is a small RNA chain with about 80 nucleotides that transfers amino acids into the ribosome for protein synthesis.
• Small nuclear RNA (snRNA) is a small RNA whose primary function is in the processing of pre-messenger RNA in the nucleus.
• MicroRNA (miRNA) is a short RNA molecule of only 20-25 nucleotide long. They are used by cells to downregulate gene expression, preventing cells from producing too much proteins.
• Small interfering RNA (siRNA) is also a type of short RNA molecule which regulates gene expression. In contrast to miRNA’s downregulating effect, siRNA can completely turn off protein production from a particular gene, thereby silencing the gene.