<prompt> Answer this question truthfullyWhat is the role of the αs-GTP complex in the adenylyl cyclase mechanism of cellular signaling, and what is the substrate and product of adenylyl cyclase catalysis?  <response>: <reason> In the adenylyl cyclase mechanism of cellular signaling, the αs-GTP complex activates adenylyl cyclase. Adenylyl cyclase then catalyzes the conversion of ATP to cAMP. 