Olfactory receptor

Chemoreceptors expressed in cell membranes of olfactory receptor neurons

Olfactory receptors (ORs), also known as odorant receptors, are chemoreceptors expressed in the cell membranes of olfactory receptor neurons and are responsible for the detection of odorants which give rise to the sense of smell. Activated olfactory receptors trigger nerve impulses which transmit information about odor to the brain. In vertebrates, these receptors are members of the class A rhodopsin-like family of G protein-coupled receptors (GPCRs). The olfactory receptors form the largest multigene family in vertebrates consisting of around 400 genes in humans and 1400 genes in mice. In insects, olfactory receptors are members of an unrelated group of ligand-gated ion channels.

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