Specific binding of CAP-50 to calcyclin.
CAP-50, a calcyclin-associated protein with an apparent molecular mass of 50 kDa, was purified and proved to be a novel annexin [Tokumitsu, H. et al. (1992) J. Biol. Chem. 267, 8919-8924]. We examined the binding of CAP-50 to other Ca(2+)-binding proteins which have two of four EF-hand structures, by a co-precipitation assay with phospholipid (phosphatidylserine). Among nine Ca(2+)-binding proteins (calcyclin, S-100 proteins, p11, calgizzarin, calvasculin, calmodulin and troponin C) examined, only calcyclin interacted with CAP-50. These results clearly show that the interaction of CAP-50 to calcyclin is specific, i.e. other Ca(2+)-binding proteins with the EF-hand structure could not substitute for calcyclin, thereby suggesting the possible role in specific regulation of the function of CAP-50 by Ca2+/calcyclin.
Minami
H
H
Department of Pharmacology, Nagoya School of Medicine, Japan.
Tokumitsu
H
H
Mizutani
A
A
Watanabe
Y
Y
Watanabe
M
M
Hidaka
H
H
D000818:Animals; D017302:Annexins / Q000378:metabolism*; D002135:Calcium-Binding Proteins / Q000378:metabolism*; D011232:Chemical Precipitation; D011485:Protein Binding; D011817:Rabbits; D009418:S100 Proteins
D017302:Annexins; D002135:Calcium-Binding Proteins; D009418:S100 Proteins; C074368:calcyclin-associated protein 50