Structural basis of epilepsy-related ligand-receptor complex LGI1-ADAM22.Yamagata, A., Miyazaki, Y., Yokoi, N., Shigematsu, H., Sato, Y., Goto-Ito, S., Maeda, A., Goto, T., Sanbo, M., Hirabayashi, M., Shirouzu, M., Fukata, Y., Fukata, M., Fukai, S.
(2018) Nat Commun 9: 1546-1546
- PubMed: 29670100
- DOI: 10.1038/s41467-018-03947-w
- Primary Citation of Related Structures:
- PubMed Abstract:
Epilepsy is a common brain disorder throughout history. Epilepsy-related ligand-receptor complex, LGI1-ADAM22, regulates synaptic transmission and has emerged as a determinant of brain excitability, as their mutations and acquired LGI1 autoantibodies ...
Epilepsy is a common brain disorder throughout history. Epilepsy-related ligand-receptor complex, LGI1-ADAM22, regulates synaptic transmission and has emerged as a determinant of brain excitability, as their mutations and acquired LGI1 autoantibodies cause epileptic disorders in human. Here, we report the crystal structure of human LGI1-ADAM22 complex, revealing a 2:2 heterotetrameric assembly. The hydrophobic pocket of the C-terminal epitempin-repeat (EPTP) domain of LGI1 binds to the metalloprotease-like domain of ADAM22. The N-terminal leucine-rich repeat and EPTP domains of LGI1 mediate the intermolecular LGI1-LGI1 interaction. A pathogenic R474Q mutation of LGI1, which does not exceptionally affect either the secretion or the ADAM22 binding, is located in the LGI1-LGI1 interface and disrupts the higher-order assembly of the LGI1-ADAM22 complex in vitro and in a mouse model for familial epilepsy. These studies support the notion that the LGI1-ADAM22 complex functions as the trans-synaptic machinery for precise synaptic transmission.
Institute for Quantitative Biosciences, The University of Tokyo, Tokyo, 113-0032, Japan.