Purification and characterization of a novel calcium-binding protein, S100C, from porcine heart.
A novel Ca(2+)-binding protein, which we have named S100C (Ohta et al. (1991) FEBS Lett. 295, 93-96), was purified to homogeneity from porcine heart by Ca(2+)-dependent dye-affinity chromatography. S100C possesses some properties of S100 proteins, such as self-association and exposure of a hydrophobic site upon binding of Ca2+ but it differs from S100 proteins in forms of its isoelectric point (pI = 6.2), cross-reactivity with antibodies, staining by Stains-all, and its Ca(2+)-dependent interaction with the immobilized dye. S100C bound to cytoskeletal components at physiological concentrations of Ca2+. Moreover, it was found that 125I-labeled S100C interacted with annexin I in a Ca(2+)-dependent manner. S100C also inhibited the phosphorylation of annexin I by protein kinase C. These data suggest that S100C might act to regulate the cytoskeleton in a Ca(2+)-dependent manner via interactions with annexin I.
Naka
M
M
Department of Molecular and Cellular Pharmacology, Mie University School of Medicine, Japan.
Qing
Z X
ZX
Sasaki
T
T
Kise
H
H
Tawara
I
I
Hamaguchi
S
S
Tanaka
T
T
D000818:Animals; D017305:Annexin A1 / Q000737:chemistry; D002118:Calcium / Q000494:pharmacology; D002135:Calcium-Binding Proteins / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D007526:Isoelectric Point; D009206:Myocardium / Q000737:chemistry*; D010766:Phosphorylation / Q000187:drug effects; D011493:Protein Kinase C / Q000037:antagonists & inhibitors; D009418:S100 Proteins / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D013552:Swine
D017305:Annexin A1; D002135:Calcium-Binding Proteins; D009418:S100 Proteins; C072337:S100A11 protein, human; D011493:Protein Kinase C; D002118:Calcium