Adenylyl Cyclase Has the Opposite Effect of Which of the Following

Question

Adenylyl cyclase has the opposite effect of which of the following?
A) protein kinase
B) protein phosphatase
C) phosphodiesterase
D) phosphorylase
E) GTPase

Accepted Answer

Adenylyl cyclase generates cAMP, while phosphodiesterase breaks down cAMP. Therefore, they have opposite effects on the level of cAMP in the cell. Protein kinase, protein phosphatase, phosphorylase, and GTPase are not directly involved in cAMP signaling and do not have opposite effects to adenylyl cyclase.