CNTNAP2

Contactin-associated protein-like 2 (CNTNAP2), alias CASPR2, is a transmembrane neurexin superfamily member. It localizes at myelinated axons’ juxtaparanodal regions, interacting with contactin 1 to stabilize axon-glial junctions and maintain voltage-gated potassium channel clusters—critical for saltatory nerve conduction.
CNTNAP2 variants link to autism spectrum disorder, schizophrenia, and epilepsy. Autoantibodies against CASPR2 cause encephalitis with neuromyotonia/limbic symptoms. Current care uses symptomatic treatments (antiepileptics, immunotherapies), while targeted therapies modulating its interactions are in preclinical research.