Final answer:
Receptor systems using guanylyl cyclase enzymes create cyclic GMP (cGMP) from GTP. This pathway functions as a signaling mechanism analogous to the adenylate cyclase system that produces cyclic AMP (cAMP) from ATP.
Step-by-step explanation:
Receptor systems relying on guanylyl cyclase enzymes employ cyclic GMP (cGMP) as a second messenger, produced through the conversion of guanosine triphosphate (GTP). This signaling pathway differs from the more familiar adenylate cyclase pathway, where cyclic AMP (cAMP) is synthesized from adenosine triphosphate (ATP).
In the cGMP system, guanylyl cyclase responds to various hormones or signaling molecules by catalyzing the transformation of GTP into cGMP. This cyclic nucleotide, akin to cAMP in the cAMP-dependent pathway, assumes a regulatory role within the cell. Through its involvement in cellular signaling, cGMP contributes to the orchestration of physiological responses, illustrating the diversity and specificity of intracellular communication pathways in maintaining cellular homeostasis and adapting to external stimuli.