Question

2. (3 pts) Would proper termination of transcription in eukaryotes be more likely to be blocked by a mutation that inactivated CstF or polyA polymerase? Explain. Grading: 1 pt for indicating which mutation would be more likely to prevent proper termination. 0.5 pt for explaining the normal function of CstF; 0.5 pt for explaining the normal function of polyA polymerase; 1 pt for explaining why the mutation you chose would be more likely to prevent proper termination, with reference to the mechanism of termination.

Answer 1

Ans:

Mutation in CstF can be more detrimental and cause termination of transcription.

CstF binds to RNA polymerase II and cleaves RNA before termination. It also signals the RNA polymerase II to slip off the transcript.

Poly-adenine tail is added to the RNA from adenosine triphosphate cleaving off pyrophosphate.

Mutation in CstF causes termination, since functional CstF gives siganl to RNA polymerase to slip off the transcript.