Imagine that you have isolated a yeast mutant that contains a constitutively (constantly) active histone deacetylase. What phenotype do you predict for this mutant?
A) The mutant will grow rapidly.
B) The mutant will require galactose for growth.
C) The mutant will show low levels of gene expression.
D) The mutant will show high levels of gene expression.

Question

Quizplus · Accepted Answer

Histone deacetylases (HDACs) remove acetyl groups from histones, leading to the compaction of chromatin and repression of gene transcription. If a yeast mutant has a constitutively active HDAC, it will deacetylate histones continuously, causing chromatin to remain in a highly condensed state. This will result in a low level of gene expression, as the genes will be inaccessible to transcription factors and RNA polymerase. Thus, choice C is the best answer.

Imagine That You Have Isolated a Yeast Mutant That Contains