Which Experimental Technique Would Be Best Used to Investigate Whether

Multiple Choice

Which experimental technique would be best used to investigate whether a transcription factor is activated as part of a signal transduction pathway?

A) Measure changes in the activities of cytosolic enzymes in response to stimulation of the pathway.
B) Isolate mutants that do not bind signal molecule, and characterize the mutations in the DNA.
C) Compare the cell's messenger RNA molecules before and after stimulation of the pathway.
D) Measure intracellular calcium ion concentration changes in response to stimulation of the pathway.
E) Label the signal molecule using the radioisotope carbon-14, and observe whether the carbon-14 radiolabel enters the cell.