ACCN4 belongs to the superfamily of acid-sensing ion channels, which are proton-gated, amiloride-sensitive sodium channels. These channels have been implicated in synaptic transmission, pain perception as well as mechanoperception. ACCN4 is predominantly expressed in the pituitary gland, and might be a candidate for paroxysmal dystonic choreoathetosis (PDC), a movement disorder. FUNCTION: Probable cation channel with high affinity for sodium. These channels have been implicated in synaptic transmission, pain perception as well as mechanoperception. SUBUNIT: Homotetramer or heterotetramer with other ASIC proteins (Probable). SUBCELLULAR LOCATION: Membrane; Multi-pass membrane protein. TISSUE SPECIFICITY: This gene is predominantly expressed in the pituitary gland. Expressed in brain, spinal chord and dorsal root ganglion (DRG). Expressed by a subset of sensory neurons in the DRG. Expressed by granule cells in the cerebellar cortex. In hippocampus, expression is detected in dentate gyrus granule cells, in pyramidal cells of CA1-CA3 subfields and in interneurons of the striatum oriens and radiatum of all subfields. In cerebral cortex expressed in small, medium and large pyramidal cells in layers 2, 3 and 5 respectively. Also expressed in striatum, globus pallidus, inferior and superior calliculi, amygdala, magnocellular preoptic nucleus, islands of Calleja and large neurons of olfactory tubercules. DEVELOPMENTAL STAGE: Highly expressed in newborn spinal chord but hardly detected in the cerebellum compared to adult. Expressed at postnatal day 1 in ependymal cells lining the central canal of spinal chord and in motor neurons. In adult, expression decreases in ependymal cells and increases in motor neurons. The number of positive interneurons decreases but the individual interneuron expression increases in adult spinal chord compared to newborn. MISCELLANEOUS: In vitro, has no proton-gated channel activity.