High Quality Content by WIKIPEDIA articles! Neurochondrin (sometimes mentioned by the name of its its murine homologue, Norbin) is a protein that in humans is encoded by the NCDN gene. This gene encodes a leucine-rich cytoplasmic protein, which is highly similar to a mouse protein norbin that negatively regulates Ca/calmodulin-dependent protein kinase II phosphorylation and may be essential for spatial learning processes. Several alternatively spliced transcript variants of this gene have been described. According to one study, Norbin can modulate signaling activty and expression of metabotropic glutamate receptor 5; modulating mice with targeted deletion of NCDN in the brain have phenotypic traits usually found in the rodent models of schizophrenia, including disruptions in prepulse inhibition.