Rapid proteolysis of brain MAP-1 related cytoskeleton-associated 350kd protein by purified calpain.
Microtubule associated protein-1 of brain and its intracellular 350kd analogues were highly sensitive to purified Ca2+-dependent cysteine proteinase (calpain). After 15 second digestion, we detected intermediate degradation products of MAP-1 by immunoblotting using anti-MAP-1 antibody as 290, 260, 220, 170, 140, 112, 80, 68, and 32kd polypeptides. These values corresponded to the molecular weights of the immunoreactive polypeptides of microtubule-enriched cytoskeletons isolated from HeLa and SV-3Y1 cells, suggesting the action of endogenous calpain on intracellular MAP-1 analogues in vivo or during the course of preparation.
D000818:Animals; D000911:Antibodies, Monoclonal; D001923:Brain Chemistry; D002118:Calcium / Q000494:pharmacology; D002154:Calpain / Q000494:pharmacology*; D002417:Cattle; D003101:Collodion; D003598:Cytoskeletal Proteins / Q000378:metabolism*; D004591:Electrophoresis, Polyacrylamide Gel; D006367:HeLa Cells / Q000166:cytology; D006801:Humans; D008869:Microtubule-Associated Proteins / Q000032:analysis / Q000378:metabolism*; D008970:Molecular Weight
D000911:Antibodies, Monoclonal; D003598:Cytoskeletal Proteins; D008869:Microtubule-Associated Proteins; D003101:Collodion; D002154:Calpain; D002118:Calcium