Open AccessCalcium-dependent interaction of S100b, troponin C, and calmodulin with an immobilized phenothiazine.
Author(s) -
Daniel R. Marshak,
Daniel Watterson,
Linda J. Van Eldik
Publication year - 1981
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.78.11.6793
Subject(s) - calmodulin , troponin c , parvalbumin , phenothiazine , biochemistry , calcium binding protein , calcium , affinity chromatography , sepharose , trifluoperazine , chemistry , biology , troponin , enzyme , pharmacology , psychology , organic chemistry , neuroscience , psychiatry , myocardial infarction
We have purified the brain-specific protein S100b by affinity-based adsorption chromatography on phenothiazine-Sepharose conjugates and studied the interaction of this and other calcium-modulated proteins with the immobilized antipsychotic drug. Bovine brain calmodulin, rabbit skeletal muscle troponin C, and bovine brain S100b bind to phenothiazine-Sepharose in a calcium-dependent manner. These three proteins competitively inhibit the calcium-dependent binding of 125I-labeled chicken gizzard calmodulin to the immobilized drug. However, carp parvalbumin and chicken intestinal vitamin D-dependent calcium binding protein do not inhibit the phenothiazine--calmodulin interaction. These results suggest that the known amino acid sequence homology among calmodulin, troponin C, and S100b may be reflected in a similar functional domain present in these proteins but absent in parvalbumin and vitamin D-dependent protein.