* various types of RNA.
Answers
Answer:
messenger RNA (mRNA), transfer RNA (tRNA), and ribosomal RNA (rRNA)
Three main types of RNA are involved in protein synthesis. They are messenger RNA (mRNA), transfer RNA (tRNA), and ribosomal RNA (rRNA).
mRNA
mRNA is transcribed from DNA and contains the genetic blueprint to make proteins. Prokaryotic mRNA does not need to be processed and can proceed to synthesize proteins immediately. In eukaryotes, a freshly transcribed RNA transcript is considered a pre-mRNA and needs to undergo maturation to form mRNA. A pre-mRNA contains non-coding and coding regions known as introns and exons, respectively. During pre-mRNA processing, the introns are spliced, and the exons are joined together. A 5’ cap known as 7-methylguanosine is added to the 5’ end of the RNA transcript and the 3’ end is polyadenylated.
tRNA
tRNAs are RNA molecules that translate mRNA into proteins. They have a cloverleaf structure that consists of a 3’ acceptor site, 5’ terminal phosphate, D arm, T arm, and anticodon arm. The primary function of a tRNA is to carry amino acids on its 3’ acceptor site to a ribosome complex with the help of aminoacyl-tRNA synthetase.
rRNA
rRNA forms ribosomes, which are essential in protein synthesis. A ribosome contains a large and small ribosomal subunit. In prokaryotes, a small 30S and large 50S ribosomal subunit make up a 70S ribosome. In eukaryotes, the 40S and 60S subunit form an 80S ribosome. The ribosomes contain an exit (E), peptidyl (P), and acceptor (A) site to bind aminoacyl-tRNAs and link amino acids together to create polypeptides.