Cyclic nucleotide-gated channel subunit alpha-4 (CNGA4)

Cyclic nucleotide-gated channel subunit alpha-4 (CNGA4) is a modulatory subunit of olfactory cyclic nucleotide-gated (CNG) ion channels, primarily expressed in sensory neurons of the olfactory epithelium[1][3][5]. It combines with other subunits (mainly CNGA2 and CNGB1b) to form heterotetrameric channels responsible for converting odorant signals into electrical impulses by allowing calcium and sodium ions to enter the neuron when activated by cyclic nucleotides like cAMP or cGMP[2][4][6]. CNGA4's presence is crucial for rapid adaptation to odorants, achieved via Ca²⁺-calmodulin-dependent feedback inhibition, allowing olfactory neurons to quickly adjust their sensitivity to persistent stimuli[2][3]. Mutations in CNGA4 have been linked to specific retinal and multisystemic diseases, but as of now, the protein is not a target for approved drug therapies. CNGA4 serves mainly as a molecular component in the physiology of smell rather than a direct pharmacological target[1][2][5].

Other names

CNG channel alpha-4CNGa4OCNC2OCNCbCNG5Olfactory cyclic nucleotide-gated channel subunit 2CNCA2CNG-4CNG4CNGB2 (historical/misused, see notes)OCNCBETAcyclic nucleotide-gated channel alpha-4cyclic nucleotide gated channel alpha 4cyclic nucleotide-gated cation channel alpha-4

Blockade: Non-specific blockade by cyclic nucleotide-gated channel inhibitors. Modulation: Activity modulated by cyclic nucleotides (cAMP, cGMP), calcium/calmodulin for channel adaptation. No approved direct therapeutic mechanism via CNGA4.