Calcium, potassium:sodium antiporter that transports 1 Ca(2+) and 1 K(+) in exchange for 4 Na(+) (PubMed:22057188). Controls the rapid response termination and proper regulation of adaptation in olfactory sensory neurons (OSNs) which subsequently influences how odor information is encoded and perceived (PubMed:22057188). May play a role in calcium transport during amelogenesis (PubMed:23375655). Ca(2+)(out) + K(+)(out) + 4 Na(+)(in) = Ca(2+)(in) + K(+)(in) + 4 Na(+)(out) Expressed in late secretory-stage and maturation-stage ameloblasts, with significantly increased expression during the late stages of amelogenesis (at protein level) (PubMed:22677781, PubMed:24621671, PubMed:26247047). Widely expressed in most regions of the brain, including hippocampus, neocortex, thalamus, striatum and olfactory bulb (PubMed:12379639). Expressed in the olfactory sensory neurons (PubMed:22057188). Mice have a reduced ability to locate an odorous source and lower body weights. The olfactory sensory neurons display defects in response termination and adaptation but have unchanged sensitivity (PubMed:22057188). Mice show severe enamel defects (PubMed:23375655). Belongs to the Ca(2+):cation antiporter (CaCA) (TC 2.A.19) family. SLC24A subfamily. It is uncertain whether Met-1 or Met-18 is the initiator. Truncated N-terminus. Probable cloning artifact.