Given below are two statements:Statement I: Transfer RNAs and ribosomal RNAdo not interact with mRNA.Statement II: RNA interference (RNAi) takesplace in all eukaryotic organisms as a method ofcellular defence.In the light of the above statements, choose themost appropriate answer from the options givenbelow
Answer
Role of tRNA, rRNA, and RNAi in Protein Synthesis and Cellular Defence
1. tRNA (Transfer RNA)
- Function: tRNA plays a key role in translation, the process of synthesizing proteins from mRNA.
- Mechanism: Each tRNA has an anticodon that pairs with a complementary codon on the mRNA strand. It also carries a specific amino acid.
- During translation, the tRNA matches its anticodon to the mRNA codon, adding the correct amino acid to the growing polypeptide chain.
- Importance: Ensures the correct sequence of amino acids in the protein.
2. rRNA (Ribosomal RNA)
- Function: rRNA is a fundamental part of the ribosome, which is the cellular machinery for protein synthesis.
- Role: Assists in the proper alignment of mRNA and tRNA during translation.
- rRNA also has catalytic activity that helps form peptide bonds between amino acids.
- Importance: Provides both structural support and enzymatic function to the ribosome.
3. RNA Interference (RNAi)
- Definition: RNAi is a natural cellular mechanism found in all eukaryotic organisms used to regulate gene expression and defend against foreign genetic elements.
- Function: Small RNA molecules (like siRNA or miRNA) bind to complementary mRNA, leading to translation inhibition or mRNA degradation.
- Significance:
- Regulates gene expression.
- Protects against viruses and transposons.
- Used in biotechnology and medicine for gene silencing therapies.