Human Cyclic nucleotide-gated cation channel alpha-4
Domain
The C-terminal coiled-coil domain mediates trimerization of CNGA subunits.
Function
Pore-forming subunit of the olfactory cyclic nucleotide-gated channel. Operates in the cilia of olfactory sensory neurons where chemical stimulation of the odorant is converted to an electrical signal. Mediates odorant-induced cAMP-dependent Ca(2+) influx triggering neuron depolarization. The rise of intracellular Ca(2+) levels potentiates the olfactory response by activating Ca(2+)-dependent Cl(-) channels, but it also serves as a negative feedback signal to desensitize the channel for rapid adaptation to odorants. Conducts cAMP- and cGMP-gated ion currents, with permeability for monovalent and divalent cations.
Sequence Similarities
Belongs to the cyclic nucleotide-gated cation channel (TC 1.A.1.5) family. CNGA4 subfamily.
Cellular localization
- Cell projection
- Cilium membrane
- Multi-pass membrane protein
Alternative names
Cyclic nucleotide-gated channel alpha-4, CNG channel alpha-4, CNGa4, Olfactory cyclic nucleotide-gated channel subunit 2, OCNC2, CNGA4