Question

Name the enzyme that catalyses the transcription of hnRNA.

(ii) Why does the hnRNA need to undergo changes ? List the changeshnRNA undergoes and wher e in the cell such changes take pl ace.

Answer 1

i. Transcription of hnRNA or precursor RNA is catalysed by RNA polymerase II.
ii. hnRNA contain non-coding sequences called introns which are removed to form mature mRNA, thus it is processed. hnRNA undergo splicing (removal of introns), capping and tailing in the nucleus. Capping and tailing increases the stability of mRNA and make translation more efficient.