If a mutation causes a decrease in the activity of histone acetyltransferases, histones will most likely have a _______ affinity for DNA, and there will be _______ in transcription rates.
A) greater; an increase
B) greater; a decrease
C) reduced; an increase
D) reduced; no change
E) reduced; a decrease

Question

Quizplus · Accepted Answer

Histone acetyltransferases add acetyl groups to histones, decreasing their positive charge and reducing their affinity for the negatively charged DNA. This loosening allows transcription machinery better access to DNA. If their activity decreases, histones will bind DNA more tightly, hindering transcription, thus leading to a decrease in transcription rates.

If a Mutation Causes a Decrease in the Activity of Histone