As a component of the outer core of AMPAR complex, may be involved in synaptic transmission in the central nervous system. In hippocampal neurons, in presynaptic terminals, plays an important role in the final steps of neurotransmitter release, possibly by regulating Ca(2+)-sensing. In the cerebellum, may inhibit SNARE complex formation and down-regulate short-term facilitation. . This is the function of PRRT2 (proline rich transmembrane protein 2, ENSG00000167371).