Question

______ enzyme recruit _______ enzyme to spread change / covalent modification to histones along DNA to promote heterochromatin state.

A) DNA polymerase, RNA polymerase
B) Histone acetyltransferase, DNA methyltransferase
C) Histone methyltransferase, DNA methyltransferase
D) RNA polymerase, Histone acetyltransferase

Answer 1

The enzymes that recruit each other to promote a heterochromatin state by spreading covalent modifications along DNA are histone methyltransferases and DNA methyltransferases (Answer: C).

Step-by-step explanation:

The correct answer to the question "enzyme recruit enzyme to spread change / covalent modification to histones along DNA to promote heterochromatin state" is C) Histone methyltransferase, DNA methyltransferase. Histone methyltransferases modify histones by adding methyl groups, primarily to lysines and arginines, which can lead to a change in the chromatin structure and influence gene transcription. In the context of promoting a heterochromatin state, which is a more compact and transcriptionally inactive state, histone methyltransferases can add methyl groups to specific histones that recruit DNA methyltransferases. The DNA methyltransferases then methylate DNA at cytosine bases adjacent to guanine nucleotides (CpG sites), reinforcing the condensed structure of heterochromatin and helping to maintain gene silencing.