Guanine nucleotide-binding proteins (G proteins) are involved as modulators or transducers in various transmembrane signaling systems. G(olf) alpha mediates signal transduction within the olfactory neuroepithelium and the basal ganglia. May be involved in some aspect of visual transduction, and in mediating the effect of one or more hormones/neurotransmitters. G proteins are composed of 3 units; alpha, beta and gamma. The alpha chain contains the guanine nucleotide binding site. Interacts with GAS2L2 (PubMed:23994616). Detected in olfactory neuroepithelium, brain, testis, and to a lower extent in retina, lung alveoli, spleen. Trace amounts where seen in kidney, adrenal gland and liver. Found to be expressed in all the insulinomas examined. The disease is caused by variants affecting the gene represented in this entry. Belongs to the G-alpha family. G(s) subfamily.