Selectivity of plasma membrane calcium ATPase (PMCA)-mediated extrusion of toxic divalent cations in vitro and in cultured cells.

In the recent years, the toxicity of certain divalent cations has been associated with the alteration of intracellular Ca homeostasis. Among other mechanisms, these cations may affect the functionality of certain Ca-binding proteins and/or Ca pumps. The plasma membrane calcium pump (PMCA) maintains Ca homeostasis in eukaryotic cells by mediating the efflux of this cation in a process coupled to ATP hydrolysis.