Question

Given below is a part of the template strand of a structural gene:
TAG CAT TAG GAT

Explain the mechanism involved in initiation of transcription of this strand.

Answer 1

RNA polymerase binds to the promoter, aided in prokaryotes by the sigma initiation factor. It locally opens the DNA and begins joining complementary ribonucleotides, using the 3′→5′ template to synthesise RNA 5′→3′.