CRIP1a inhibits endocytosis of G-protein coupled receptors activated by endocannabinoids and glutamate by a common molecular mechanism.

The excitability of the central nervous system depends largely on the surface density of neurotransmitter receptors. The endocannabinoid receptor 1 (CB R) and the metabotropic glutamate receptor mGlu R are expressed pre-synaptically where they reduce glutamate release into the synaptic cleft. Recently, the CB R interacting protein cannabinoid receptor interacting protein 1a (CRIP1a) was identified and characterized to regulate CB R activity in neurons.