Cyclic AMP Signaling in the Main Olfactory Epithelium

In vertebrates, the majority of olfactory sensory neurons (OSNs) respond to odor cues through a cyclic adenosine monophosphate (cAMP)–mediated signaling cascade. Studies over the past three decades have elucidated the core components of the olfactory transduction pathway. Additionally, many of the mechanisms that regulate the transduction process have been explored, including those that may regulate the size and duration of the cAMP transient as well as those that may regulate the impact of cAMP. Regulation of this transduction mechanism governs the alteration of the sensitivity and response kinetics of the olfactory system, thereby allowing the system to accommodate highly variable environmental stimuli. In addition to its critical role in olfactory transduction, cAMP also regulates other cellular processes in OSNs including the targeting of OSN axons during development.