Plasma membrane calcium-transporting ATPase 1 (PMCA1)

Plasma membrane calcium transporting ATPases are enzymes belonging to the P-type primary ion transport ATPase family. They use energy from hydrolysis of adenosine triphosphate (ATP) to actively extrude bivalent calcium ions from eukaryotic cells against steep concentration gradients. This process is essential for maintaining low cytosolic Ca²⁺ concentrations required for proper cellular signaling and function across all tissues. There are several isoforms encoded by different genes (ATP2B1, ATP2B2, etc.), each with tissue-specific expression patterns regulated developmentally and physiologically. PMCA plays critical roles in regulating blood pressure through effects on vascular smooth muscle tone; it also supports bone mineralization by facilitating intestinal absorption of dietary calcium. In neurons, PMCAs help shape synaptic responses by controlling local Ca²⁺ dynamics at synapses. Mutations or dysregulation can contribute to diseases such as intellectual disability syndromes (via ATP2B1), hypertension/preeclampsia during pregnancy (via placental transfer), hearing loss (via other isoforms), among others. While not a common direct drug target clinically at present, its central role makes it an important focus for understanding pathophysiology related to disturbed cellular calcium handling.

Other names

Plasma membrane calcium pump isoform 1Ca²⁺ ATPase (specifically, plasma membrane type)ATP2B1 (gene name)PMCA (family abbreviation)

Drugs or toxins that inhibit these pumps would increase intracellular Ca²⁺ by blocking active extrusion; conversely, activators would enhance removal of cytosolic Ca²⁺. The main mechanism is modulation of active transport across membranes using energy from ATP hydrolysis.