Question

A transcriptional repressor that controls the transcription of gene A is not normally active unless bound by an effector molecule X. In a certain cell, the domain of the repressor that binds X is mutated. With all other factors being the same, what effect do you predict on the transcription of gene A?

A. The transcription of gene A will not be affected.

B. The effect on the transcription of gene A cannot be predicted.

C. The transcription of gene A will increase.

D. The transcription of gene A will decrease.

Answer 1

C

Step-by-step explanation:

I think its C . A transcriptional repressor usually represses the transcription pathway when its active. According to the question, the repressor is not usually active until an effector molecule binds to it making it active and blocking the transcription pathway. So if the region where the effector binds on the repressor is mutated i.e. it turns nonfunctional that means the effector cannot bind to repressor which means repressor cannot become active to block transcription which in turn increases the transcription of gene A because repressor cannot repress it since it is inactive due to its inability to bind to the effector.

ALOT of words please lmk if it makes sense