Reelin Molecules Assemble together to Form a Large Protein Complex, Which Is Inhibited by the Function-Blocking CR-50 Antibody

• Published in: Proceedings of the National Academy of Sciences - PNAS 2000-08, Vol.97 (17), p.9729-9734
• Main Authors: Utsunomiya-Tate, Naoko, Kubo, Ken-ichiro, Tate, Shin-ichi, Kainosho, Masatsune, Katayama, Eisaku, Nakajima, Kazunori, Mikoshiba, Katsuhiko
• Format: Article
• Language: English
• Subjects: Animals; Antibodies; Antibodies - immunology; Antibodies - pharmacology; Binding Sites; Biological Sciences; Biology; Biopolymers - chemistry; Biopolymers - genetics; Biopolymers - immunology; Biopolymers - metabolism; Cell adhesion; Cell Adhesion - drug effects; Cell Adhesion Molecules, Neuronal - genetics; Cell Adhesion Molecules, Neuronal - immunology; Cell Adhesion Molecules, Neuronal - metabolism; Cell Adhesion Molecules, Neuronal - ultrastructure; Cell Line; Cells, Cultured; Cultured cells; Dose-Response Relationship, Immunologic; Epitopes; Epitopes - genetics; Epitopes - immunology; Epitopes - metabolism; Epitopes - ultrastructure; Extracellular Matrix Proteins - genetics; Extracellular Matrix Proteins - immunology; Extracellular Matrix Proteins - metabolism; Extracellular Matrix Proteins - ultrastructure; Macromolecular Substances; Mammals; Mice; Mice, Mutant Strains; Microscopy, Electron; Models, Biological; Molecules; Monomers; Mutation - genetics; Nerve Tissue Proteins - metabolism; Nervous system; Neurology; Neurons; Phosphorylation; Phosphotyrosine - metabolism; Polymers; Protein Binding - drug effects; Proteins; Recombinant Proteins - genetics; Recombinant Proteins - immunology; Recombinant Proteins - metabolism; Recombinant Proteins - ultrastructure; reelin; Reelin Protein; Serine Endopeptidases; Signal Transduction; Solubility; Static Electricity; Transfection
• ISSN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.160272497

Reelin is a key mediator of ordered neuronal alignment in the brain. Here, we demonstrate that Reelin molecules assemble with each other to form a huge protein complex both in vitro and in vivo. The Reelin-Reelin interaction clearly is inhibited by the function-blocking anti-Reelin antibody, CR-50, at a concentration known to inhibit Reelin function. This assembly is mediated by electrostatic interaction of the CR-50 epitope region. Recombinant CR-50 epitope fragments spontaneously constitute a soluble, string-like homopolymer with a regularly repeated structure composed of more than 40 monomers. Mutated Reelin, which lacks the CR-50 epitope region, cannot form a homopolymer and fails to induce efficient tyrosine phosphorylation of Disabled 1 (Dab 1), which should occur to transduce the Reelin signal. These data suggest that Reelin exerts its biological function by composing a large protein assembly driven by the CR-50 epitope region, proposing a novel model of the Reelin signaling in neurodevelopment.