Reelin molecules assemble together to form a large protein complex, which is inhibited by the function-blocking CR-50 antibody.
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 (Dab1), 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.
Laboratory for Developmental Neurobiology, Brain Science Institute, RIKEN, Wako, Saitama, Japan.
N
N
Utsunomiya-Tate
K
K
Kubo
S
S
Tate
M
M
Kainosho
E
E
Katayama
K
K
Nakajima
K
K
Mikoshiba
D000818:Animals; D000906:Antibodies / Q000276:immunology* / Q000494:pharmacology; D001665:Binding Sites; D001704:Biopolymers / Q000737:chemistry / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D002448:Cell Adhesion / Q000187:drug effects; D015816:Cell Adhesion Molecules, Neuronal / Q000235:genetics / Q000276:immunology* / Q000378:metabolism* / Q000648:ultrastructure; D002460:Cell Line; D002478:Cells, Cultured; D004306:Dose-Response Relationship, Immunologic; D000939:Epitopes / Q000235:genetics / Q000276:immunology / Q000378:metabolism / Q000648:ultrastructure; D016326:Extracellular Matrix Proteins / Q000235:genetics / Q000276:immunology* / Q000378:metabolism* / Q000648:ultrastructure; D046911:Macromolecular Substances; D051379:Mice; D008817:Mice, Mutant Strains; D008854:Microscopy, Electron; D008954:Models, Biological; D009154:Mutation / Q000235:genetics; D009419:Nerve Tissue Proteins / Q000378:metabolism; D010766:Phosphorylation; D019000:Phosphotyrosine / Q000378:metabolism; D011485:Protein Binding / Q000187:drug effects; D011994:Recombinant Proteins / Q000235:genetics / Q000276:immunology / Q000378:metabolism / Q000648:ultrastructure; D000091042:Reelin Protein; D012697:Serine Endopeptidases; D015398:Signal Transduction; D012995:Solubility; D055672:Static Electricity; D014162:Transfection
D000906:Antibodies; D001704:Biopolymers; D015816:Cell Adhesion Molecules, Neuronal; C103773:Dab1 protein, mouse; D000939:Epitopes; D016326:Extracellular Matrix Proteins; D046911:Macromolecular Substances; D009419:Nerve Tissue Proteins; D011994:Recombinant Proteins; D000091042:Reelin Protein; D019000:Phosphotyrosine; C000717128:Reln protein, mouse; D012697:Serine Endopeptidases