Question

Genes can have more than one enhancer. Typically each enhancer acts independently and only one enhancer needs to be active under a given condition for the gene to be transcribed. In addition, different enhancers typically are active under different conditions, in different cell types or at different times during development. Consider a gene that is not transcribed in the absence of estrogen or progesterone, and is transcribed in the presence of either estrogen, progesterone or both. This gene contains two enhancers, labeled E1 and E2 in the diagram below. You have a wild-type cone of this gene (part A of the figure below) and three mutant versions, one that lacks the E1 enhancer (part B of the figure below), one that lacks the E2 enhancer (part C of the figure below), and one that lacks both (part D of the figure below). You transfect your clones into tissue culture cells and assay transcription of your reporter in the presence of estrogen (column labeled +Est) and in the presence of progesterone (column labeled +Pro).

Txn +Est Txn +Pro A. E1 E2 P Reporter Yes Yes B. E2 P Reporter Yes No C. E1 р Reporter No Yes D. Р Reporter No No

A. E1 regulates (activates) transcription of your gene in response to both estrogen and progesterone.

B. E2 regulates (activates) transcription of your gene in response to both estrogen and progesterone.

C. E1 regulates (activates) transcription of your gene in response to estrogen but not in response to progesterone.

D. E1 regulates (activates) transcription of your gene in response to progesterone but not in response to estrogen.

E. E2 regulates (activates) transcription of your gene in response to estrogen but not in response to progesterone.

F. E2 regulates (activates) transcription of your gene in response to progesterone but not in response to estrogen.

Answer 1

According to the experiment results

E1 regulate expression of gene in presence of progesterone

E2 regulate expression of gene in presence of estrogen

According to these observation option D and E are correct

D. E1 regulates (activates) transcription of your gene in response to progesterone but not in response to estrogen.

E. E2 regulates (activates) transcription of your gene in response to estrogen but not in response to progesterone