From its humble beginnings as the identified target of a toxin in black widow venom, to its current status as suspected culprit in some cases of schizophrenia and autism, neurexin fascinates basic scientists and clinicians alike.
Anchored in the tip of an axon, neurexin binds to molecules on the receiving end of the synapse. This interaction across the synaptic cleft assembles the working parts of synapses and influences how they work. Because miniscule changes in synapse function can cascade into substantial changes in how signals are routed through the brain, mutations of neurexin and its associated molecules can aid us in understanding the basics of communication across the synapse, and what goes wrong in brain disorders like schizophrenia.
Using Clapcote's recent review article (Reichelt et al., 2011) as a starting point, Clapcote and Südhof guided a discussion of this multifaceted molecule that boasts thousands of isoforms and multiple binding partners. How might neurexin participate in specifying the different synapse types in the brain, and how might it shape our understanding of brain disorders like autism and schizophrenia as "synaptopathies" stemming from dysfunctional synapses?
Suggested Reading: Reichelt AC, Rodgers RJ, Clapcote SJ. The role of neurexins in schizophrenia and autistic spectrum disorder. Neuropharmacology. 2011 Jan 22. Abstract