Effects of Kinase Inhibitors and Taurine Analogues on the Phosphorylation of Specific Proteins in Mitochondrial Fractions of Rat Heart and Retina
We have demonstrated that taurine at physiological concentrations inhibits the phosphorylation of specific proteins in mitochondrial fractions of the rat heart and retina2, 5. However, while the functions of these proteins, specifically an ∼44 kDa phosphoprotein present in the heart and an ∼20 kDa phosphoprotein present in the retina, are unknown we have considered it worthwhile to characterize these proteins with respect to a number of parameters. The concentration-response relationships of the effects of taurine and a series of taurine analogues on the phosphorylation of both the ∼44 kDa5 and ∼20 kDa proteins have been studied. In addition, we have characterized both proteins with respect to the nature of the phosphate bond, the identification of the phosphorylated amino acid, the isoelectric point of the proteins, and the partition of the proteins into an aqueous phase rather than a lipid phase3, 4, 5.
KeywordsKinase Inhibitor Mitochondrial Fraction Combination Index Calmodulin Antagonist Phosphorylated Amino Acid
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