Cadherin adhesion receptors involved in brain patterning

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CADHERIN

MASATOSHI

ADHESION

RECEPTORS

INVOLVED

IN BRAIN

PATTERNING

TAKEICHI

Department

of Biophysics,

Faculty of Science, Kyoto University,

Kyoto 606-8502, Japan

Formation of neural networks is a type of cell-cell adhesion phenomenon. Migrating axons recognize their target neurons, adhere to them, and finally establish synaptic connections. These years, various diffusible factors controlling axon migration were identified and their functions were elucidated. However, it still remains unknown how neurons recognize particular targets, and generate synaptic junctions with them. Recently, it was found that the cadherin adhesion apparatus is a component of synaptic junctions. Furthermore, we found that each cadherin subtype was expressed in a specific subset of neuronal circuits. These findings led us to propose the model that cadherin adhesion receptors are involved in connecting neurons one by one so as to organize the neuronal networks. Our recent genetic approaches have revealed that dysfunction of a neuronal cadherin in Drosophila causes severe disorganization in brain structures, supporting our hypothesis.

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SOBUE

of Neurochemistry Osaka 5650871

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