Analyzing Mutations in the GAL80 and GAL3 Indicate That

Question

Analyzing mutations in the GAL80 and GAL3 indicate that:
A)both GAL80 and GAL3 inhibit GAL gene expression.
B)both GAL80 and GAL3 promote GAL gene expression.
C)GAL80 promotes GAL gene expression,and GAL3 inhibits GAL gene expression.
D)GAL80 inhibits GAL gene expression,and GAL3 promotes GAL gene expression.
E)GAL80 and GAL3 are not involved in GAL expression.

Accepted Answer

GAL80 is a repressor that inhibits GAL gene expression by binding to GAL4, a transcriptional activator necessary for GAL gene expression. GAL3, on the other hand, promotes GAL gene expression by relieving the inhibition imposed by GAL80 on GAL4, thus allowing transcription of GAL genes.