Higher-Order Architecture of Cell Adhesion Mediated by Polymorphic Synaptic Adhesion Molecules Neurexin and Neuroligin

作者：Tanaka Hiroki; Miyazaki Naoyuki; Matoba Kyoko; Nogi Terukazu; Iwasaki Kenji; Takagi Junichi^*

来源：Cell Reports, 2012, 2(1): 101-110.

DOI：10.1016/j.celrep.2012.06.009

Polymorphic adhesion molecules neurexin and neuroligin (NL) mediate asymmetric trans-synaptic adhesion, which is crucial for synapse development and function. It is not known whether or how individual synapse function is controlled by the interactions between variants and isoforms of these molecules with differing ectodomain regions. At a physiological concentration of Ca2+, the ectodomain complex of neurexin-1 beta isoform (Nrx1 beta) and NL1 spontaneously assembled into crystals of a lateral sheet-like super-structure topologically compatible with transcellular adhesion. Correlative light-electron microscopy confirmed extracellular sheet formation at the junctions between Nrx1 beta- and NL1-expressing non-neuronal cells, mimicking the close, parallel synaptic membrane apposition. The same NL1-expressing cells, however, did not form this higher-order architecture with cells expressing the much longer neurexin-1 alpha isoform, suggesting a functional discrimination mechanism between synaptic contacts made by different isoforms of neurexin variants.

• 出版日期2012-7