ATP-driven Ca(2+) ion pump involved in the maintenance of basal intracellular Ca(2+) levels at the presynaptic terminals (PubMed:25953895, PubMed:27035656, PubMed:22912398, PubMed:18029012). Uses ATP as an energy source to transport cytosolic Ca(2+) ions across the plasma membrane to the extracellular compartment (PubMed:25953895, PubMed:27035656). May counter-transport protons, but the mechanism and the stoichiometry of this Ca(2+)/H(+) exchange remains to be established (By similarity). ATP + Ca(2+)(in) + H2O = ADP + Ca(2+)(out) + H(+) + phosphate Down-regulated by YWHAE. Interacts with PDZD11 (PubMed:12763866). Interacts (via N-terminus) with YWHAE (PubMed:18029012). Localized at parallel fiber terminals. There is a combination of two alternatively spliced domains at N-terminal site A (X and Z) and at C-terminal site C (A, B, E and G). The splice sites have mostly been studied independently. Full isoforms so far detected are isoform XA and isoform XB. Experimental confirmation may be lacking for some isoforms. Highly expressed in the cerebellum (PubMed:8187550). Expressed in adrenal glands (PubMed:27035656). Expressed in fetal skeletal muscle. The disease is caused by variants affecting the gene represented in this entry. Belongs to the cation transport ATPase (P-type) (TC 3.A.3) family. Type IIB subfamily.