hajureseptorisolut

Hajureseptorisolut are specialized sensory neurons responsible for the sense of smell. They reside in the olfactory epithelium, a patch of the nasal cavity lining the superior region of the nasal cavity.

In the olfactory epithelium, each hajureseptorisolut has a single dendrite bearing non-motile cilia that express odorant receptors, and an unmyelinated axon projecting through the cribriform plate to the olfactory bulb. The epithelium also contains sustentacular (supporting) cells and basal cells that can differentiate into new sensory neurons.

Function: Odorant molecules bind to olfactory receptors, which are G protein-coupled receptors. Activated receptors stimulate adenylyl cyclase via Golf, increasing cAMP, opening cation channels, and generating an action potential that travels to the brain via the olfactory bulb where signals are refined in glomeruli.

Genetics and receptor repertoire: Each hajureseptorisolut expresses only one allele of a single olfactory receptor gene (monogenic, monoallelic expression). The human genome contains several hundred functional olfactory receptor genes and many more pseudogenes, giving a large combinatorial space for odor detection.

Regeneration and clinical aspects: Olfactory sensory neurons turn over throughout life, sustained by basal stem cells. Damage from trauma or infections can cause loss of smell (anosmia); age-related decline is common. Research into olfaction informs fields from neuroscience to flavor science and disease biomarkers.

History: The concept of olfactory receptors was elucidated in the 1990s by Buck and Axel, who identified the large family of odorant receptor genes.