Human Contactin 3 (CNTN3) Protein

Background

Contactin 3 (CNTN3), also known as BIG-1, is a neural adhesion molecule that belongs to the contactin family and is primarily expressed in the brain, particularly in areas involved in learning and memory, such as the hippocampus and cortex. CNTN3 mediates cell-cell adhesion and axonal interactions, contributing to synaptic formation and plasticity. It interacts with other neuronal receptors and adhesion molecules to regulate axon guidance and neuronal migration during development. CNTN3 has been implicated in neurodevelopmental disorders, including autism spectrum disorders and schizophrenia, where its dysregulation disrupts synaptic connectivity and neural circuit function. Its expression is developmentally regulated, with high levels observed during embryonic and early postnatal stages. Structurally, CNTN3 features immunoglobulin and fibronectin type III domains, facilitating homophilic and heterophilic interactions that are essential for its role in neural development. Emerging research suggests that CNTN3 may also have a role in neurodegenerative diseases and brain plasticity, though its exact mechanisms remain under investigation.