Plasma membrane Ca²⁺ ATPase 2 contributes to short-term synapse plasticity at the parallel fiber to Purkinje neuron synapse

Plasma membrane Ca²⁺ ATPase 2 (PMCA2) is a fast, highly effective mechanism to control resting cytosolic Ca²⁺ and Ca ²⁺ excursions in neurons and other excitable cells. The strong expression of PMCA2 in the cerebellum and the cerebellar behavioral deficits presented by PMCA2-/-knock-out mice all point to its importance for cerebellar circuit dynamics. Here, we provide direct functional evidence for the influence of presynaptic PMCA2-mediated Ca²⁺ extrusion for short-term plasticity at cerebellar parallel fiber to Purkinje neuron synapses. Dramatic structural alterations to the Purkinje neurons in the absence of PMCA2 also suggest a strong influence of this fast PMCA2 isoform for development and maintenance of cerebellar function.