(a) Name the enzyme responsible for the transcription of tRNA and the amino acid the initiator tRNA gets linked with.
(b) Explain the role of initiator tRNA in initiation of protein synthesis. (3)
(a) The enzyme responsible for the transcription of tRNA is RNA polymerase in prokaryotes and RNA polymerase (III) in eukaryotes.
The amino acid that the initiator tRNA gets linked with is methionine in the cells of eukaryotes and formyl methionine in the cells of prokaryotes.
(b) The role of initiator tRNA in initiation of protein synthesis is as follows:
(i) It combines with methionine in the presence of amino acyl-tRNA synthetic enzymes resulting in the formation of charged tRNA.
(ii) mRNA attaches to small subunit of ribosome and charged initiator tRNA.
(iii) The large subunit of ribosome combines with the small subunit. (3)