Guanylate cyclase involved in the production of the second messenger cGMP (By similarity). Regulates chemotaxis responses toward volatile odorants in AWC sensory neurons and their avoidance in AWB sensory neurons (PubMed:8348618, PubMed:10774726). May be involved in sensitivity to quinine by regulating egl-4 activity through the production of cGMP (PubMed:23874221). Involved in phototransduction in ASJ neurons downstream of G protein coupled-photoreceptor lite-1 (PubMed:20436480). Required to maintain the expression of putative olfactory receptor str-2 in AWC neurons in adults (PubMed:10571181). In AWB and AWC sensory neurons, mediates the recognition of food oders which subsequently allows for the detection of preferred food sources (PubMed:25009271). GTP = 3',5'-cyclic GMP + diphosphate Localizes in cilium of sensory neurons. Expressed predominantly in AWC but also in AWB, ASI, ASJ and ASK sensory neurons and in I1 interneuron. The extracellular domain may not be directly implicated in the detection of volatile odorants. The protein kinase domain is predicted to be catalytically inactive. RNAi-mediated knockdown in AWB and AWC sensory neurons results in a defective preference between different food odors. Belongs to the adenylyl cyclase class-4/guanylyl cyclase family.