Question

Which RNA polymerase can bind CBP?

(a) I

(b) II

(c) III

(d) None

The question was posed to me in a national level competition.

My question comes from Transcription in Eukaryotes : RNA Polymerases topic in section Gene Expression : Transcription Prokaryotes of Cytogenetics

Answer 1

Correct option is (b) II

For explanation: CBP or C terminal binding protein binds to the C terminal tail of heptad repeats when it is phosphorylated. As RNA pol II is the only polymerase with a C terminal tail, only RNA pol II will bind the hepad repeat.