Calpain-mediated N-cadherin proteolytic processing in brain injury.
Neural-cadherin (N-cadherin), a member of the classical cadherin family of transmembrane glycoproteins, mediates cellular recognition and cell-cell adhesion through calcium-dependent homophilic interactions and plays important roles in the development and maintenance of the nervous system. Metalloproteinase is known to cleave N-cadherin, which is further cleaved by gamma-secretase. The intracellular domain of N-cadherin interacts with beta-catenin, and beta-catenin stability is critical for cell-cell adhesion and cell survival. In the present study, we showed that N-cadherin is cleaved specifically by calpain, resulting in the generation of a novel 110 kDa fragment. The cleavage occurred in ischemic brain lesions and in vitro neural cells in the presence of NMDA and ionomycin, and was restored by calpain inhibitors but not matrix metalloproteinase or gamma-secretase inhibitors. Calpain directly cleaved N-cadherin in in vitro calpain assays, and calpain inhibitors prevented its cleavage in a dose-dependent manner. Using N-cadherin deletion mutants, we found that calpain cleavage sites exist in at least four regions of the cytoplasmic domain. Treatment with NMDA induced neuronal death, and it suppressed the expression of surface N-cadherin and the N-cadherin/beta-catenin interaction, effects that were prevented by calpain inhibitor. Furthermore, calpain-mediated N-cadherin cleavage significantly affected cell-cell adhesion, AKT signaling, the N-cadherin/beta-catenin interaction and the Wnt target gene expressions through the accumulation of nuclear beta-catenin.
Jang
You-Na
YN
Department of Physiology, Ajou University School of Medicine, Suwon 443-749, Korea.
Jung
Yi-Sook
YS
Lee
Soo Hwan
SH
Moon
Chang-Hyun
CH
Kim
Chang-Hoon
CH
Baik
Eun Joo
EJ
D000818:Animals; D000831:Animals, Newborn; D019921:Biotinylation / Q000379:methods; D001930:Brain Injuries / Q000378:metabolism* / Q000473:pathology; D015820:Cadherins / Q000235:genetics / Q000378:metabolism*; D002118:Calcium / Q000378:metabolism; D002154:Calpain / Q000378:metabolism* / Q000494:pharmacology; D002478:Cells, Cultured; D004195:Disease Models, Animal; D016291:Dizocilpine Maleate / Q000494:pharmacology; D004622:Embryo, Mammalian; D004705:Endocytosis / Q000187:drug effects / Q000502:physiology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D018690:Excitatory Amino Acid Agonists / Q000494:pharmacology; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology; D005786:Gene Expression Regulation / Q000187:drug effects; D049452:Green Fluorescent Proteins / Q000235:genetics; D066298:In Vitro Techniques; D015759:Ionomycin / Q000494:pharmacology; D007476:Ionophores / Q000494:pharmacology; D051379:Mice; D008954:Models, Biological; D009154:Mutation / Q000235:genetics; D016202:N-Methylaspartate / Q000494:pharmacology; D009474:Neurons / Q000187:drug effects; D017434:Protein Structure, Tertiary / Q000187:drug effects / Q000502:physiology; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology; D013347:Subcellular Fractions / Q000187:drug effects; D014162:Transfection / Q000379:methods; D051153:Wnt Proteins / Q000378:metabolism; D051176:beta Catenin / Q000378:metabolism
D015820:Cadherins; D004791:Enzyme Inhibitors; D018690:Excitatory Amino Acid Agonists; D018691:Excitatory Amino Acid Antagonists; D007476:Ionophores; D051153:Wnt Proteins; D051176:beta Catenin; D049452:Green Fluorescent Proteins; D015759:Ionomycin; D016202:N-Methylaspartate; D016291:Dizocilpine Maleate; D051057:Proto-Oncogene Proteins c-akt; D002154:Calpain; D002118:Calcium