Your friend is studying a segment of a newly discovered virus that carries an en
ID: 64944 • Letter: Y
Question
Your friend is studying a segment of a newly discovered virus that carries an enhancer of gene expression that confers responsiveness to glucocorticoid (a hormone) on genes that are linked to it. He constructs two versions of a reporter gene: one has only a minimal promoter linked to it (which contains sites for RNA polymerase binding); the other reporter gene has both this minimal promoter plus the viral enhancer attached to it. The reporter gene allows him to measure the amount of transcription that occurs from each construct. Your friend puts each of these constructs into two different cell lines and examines the expression of the reporter gene in each cell line, as shown in Figure Q16-25. He is puzzled by these findings and asks for your help in interpreting them. Figure Q16-25
A. From these data, can you tell whether both cell lines contain glucocorticoid receptors? Why?
B. What might account for the difference in the transcription of the reporter gene in cell lines 1 and 2 after introduction of the construct containing the viral enhancer in the presence of glucocorticoid?
CONSTRUCT cell line 1 cell line 2 minimal promoter glucocorticoid level of reporter gene expression gene reporter gene 1 1000 80 enhancerExplanation / Answer
A. Yes. Level of reporter gene expression is high under the presence of glucocorticoid in both the cell lines. So, from the data you can conclude that both the cell lines contain glucocorticoid receptors.
B. The difference is due to the presence of higher number of glucocorticoid receptors in cell line 1, and very lesser number of receptors in cell line 2.
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.