3biw

From Proteopedia

proteopedia linkproteopedia link

Template:STRUCTURE 3biw

Crystal structure of the Neuroligin-1/Neurexin-1beta synaptic adhesion complex

Overview

Neurexins and neuroligins provide trans-synaptic connectivity by the Ca2+-dependent interaction of their alternatively spliced extracellular domains. Neuroligins specify synapses in an activity-dependent manner, presumably by binding to neurexins. Here, we present the crystal structures of neuroligin-1 in isolation and in complex with neurexin-1 beta. Neuroligin-1 forms a constitutive dimer, and two neurexin-1 beta monomers bind to two identical surfaces on the opposite faces of the neuroligin-1 dimer to form a heterotetramer. The neuroligin-1/neurexin-1 beta complex exhibits a nanomolar affinity and includes a large binding interface that contains bound Ca2+. Alternatively spliced sites in neurexin-1 beta and in neuroligin-1 are positioned nearby the binding interface, explaining how they regulate the interaction. Structure-based mutations of neuroligin-1 at the interface disrupt binding to neurexin-1 beta, but not the folding of neuroligin-1 and confirm the validity of the binding interface of the neuroligin-1/neurexin-1 beta complex. Our results provide molecular insights for understanding the role of cell-adhesion proteins in synapse function.

About this Structure

3BIW is a Protein complex structure of sequences from Rattus norvegicus. Full crystallographic information is available from OCA.

Reference

Structures of neuroligin-1 and the neuroligin-1/neurexin-1 beta complex reveal specific protein-protein and protein-Ca2+ interactions., Arac D, Boucard AA, Ozkan E, Strop P, Newell E, Sudhof TC, Brunger AT, Neuron. 2007 Dec 20;56(6):992-1003. PMID:18093522 Page seeded by OCA on Sun May 4 20:49:55 2008