Guanylate cyclase involved in the production of the second messenger cGMP (PubMed:9096403). Acts upstream of cGMP-dependent protein kinase egl-4, most likely by providing cGMP to the kinase in chemosensory neurons to regulate body size (PubMed:21124861, PubMed:26434723). GTP = 3',5'-cyclic GMP + diphosphate Optimum temperature is 20-25 degrees Celsius. Loses activity at temperatures above 35 degrees Celsius. Localization in cilium of sensory neurons is regulated by daf-25 (PubMed:21124861). Cilia localization may be important for regulating body size (PubMed:21124861). Localizes to small puncta around the nucleus in the perikaryon (PubMed:26434723). Enriched at the proximal segment of the cilia or at the distal dendrite tip close to the cilia (PubMed:26434723). Expressed in PHA sensory neurons and in head muscles (PubMed:9096403, PubMed:21124861). Expressed in chemosensory neurons AWC, ASE, ASJ, AUA, PHA and PHB, interneuron PVQ, several other unidentified head neurons, an excretory gland cell and head muscles (PubMed:26434723). Highly expressed in the sensory cila at the nose tip (PubMed:26434723). The protein kinase domain is predicted to be catalytically inactive. Increased body size and increased formation of dauer larvae. Double knockout with che-2 rescues the locomotion defect in the single che-2 mutant. Belongs to the adenylyl cyclase class-4/guanylyl cyclase family.