The binding of nonmuscle caldesmon from brain to microtubules. Regulations by Ca(2+)-calmodulin and cdc2 kinase.
Nonmuscle caldesmon from bovine brain bound to microtubules with a stoichiometry of five tubulin dimers to one molecule of caldesmon with values of Ka 4.5 x 10(5) M-1. The binding of caldesmon to microtubules was inhibited in the presence of Ca2+ and calmodulin. The phosphorylation of caldesmon by cdc2 kinase also eliminated the microtubule-binding activity. These results suggest that caldesmon may play a physiological role in the functions of microtubules.
Ishikawa
R
R
Department of Pharmacology, Gunma University School of Medicine, Japan.
Kagami
O
O
Hayashi
C
C
Kohama
K
K
D000818:Animals; D015153:Blotting, Western; D001921:Brain / Q000378:metabolism* / Q000648:ultrastructure; D016203:CDC2 Protein Kinase / Q000378:metabolism*; D002118:Calcium / Q000378:metabolism; D002147:Calmodulin / Q000378:metabolism*; D002148:Calmodulin-Binding Proteins / Q000378:metabolism*; D002417:Cattle; D008870:Microtubules / Q000378:metabolism*; D010766:Phosphorylation
D002147:Calmodulin; D002148:Calmodulin-Binding Proteins; D016203:CDC2 Protein Kinase; D002118:Calcium