MCTP is a novel presynaptic calcium sensor, resident within the endoplasmic reticulum, that is required for normal baseline neurotransmission, short-term synaptic plasticity and presynaptic homeostatic plasticity.
A novel region in the CaV2.1 α1 subunit regulates coupling of synaptic vesicles to CaV2.1 calcium channels, synaptic vesicle release and docking, and the size of the fast and total releasable pools of synaptic vesicles.
Genetic and electrophysiological analyses reveal that the mechanisms orchestrating the induction and expression of homeostatic plasticity are compartmentalized and operate with exquisite specificity on both sides of the synapse.
The mobilization or silencing of two heterogeneous pools of synaptic vesicles via different frequencies probably enables granule cell to Purkinje cell synapses to better discriminate between the high-rate code of sensory information and background noise.
Genetic and electrophysiology experiments provide the first direct evidence that protein kinase C is a calcium-sensing protein in post-tetanic potentiation, a form of synaptic plasticity that supports short-term memory.