G _olf : an Olfactory Neuron Specific-G Protein Involved in Odorant Signal Transduction

TLDR

Odorants trigger olfactory sensory neuron responses through an adenylate cyclase cascade mediated by a G protein, and the olfactory‑specific G protein Golf alpha shares 88 % amino‑acid identity with the stimulatory G protein Gsα. Specific antisera were used to localize Golf alpha protein to the sensory apparatus of the receptor neurons. Golf alpha, an olfactory‑specific GTP‑binding protein, is expressed exclusively in olfactory sensory neurons, is absent from six other tissues, and its expression in S49 cyc‑kin‑ cells shows it can stimulate adenylate cyclase, supporting a role in olfactory signal transduction.

Abstract

Biochemical and electrophysiological studies suggest that odorants induce responses in olfactory sensory neurons via an adenylate cyclase cascade mediated by a G protein. An olfactory-specific guanosine triphosphate (GTP)-binding protein alpha subunit has now been characterized and evidence is presented suggesting that this G protein, termed Golf, mediates olfaction. Messenger RNA that encodes Golf alpha is expressed in olfactory neuroephithelium but not in six other tissues tested. Moreover, within the olfactory epithelium, Golf alpha appears to be expressed only by the sensory neurons. Specific antisera were used to localize Golf alpha protein to the sensory apparatus of the receptor neurons. Golf alpha shares extensive amino acid identity (88 percent) with the stimulatory G protein, Gs alpha. The expression of Golf alpha in S49 cyc- kin- cells, a line deficient in endogenous stimulatory G proteins, demonstrates its capacity to stimulate adenylate cyclase in a heterologous system.