Dennig G, Sieghart W
J Neural Transm. 1984;59(2):119-32. doi: 10.1007/BF01255410.
Addition of L-glutamate or several citric acid cycle intermediates stimulated the phosphorylation of a protein with apparent molecular weight of 43,000 ( P43 ) in P2-fractions from rat cerebral cortex, and this phosphorylation was inhibited by dichloroacetic acid, a specific inhibitor of pyruvate dehydrogenase kinase. Comparison of several molecular properties of phosphorylated P43 and the phosphorylated alpha-subunit of pyruvate dehydrogenase indicated that both proteins are extracted by a similar procedure and have an identical apparent molecular weight and isoelectric point. Furthermore, digestion of both phosphorylated proteins by several different proteases in the presence of SDS yielded a similar pattern of phosphorylated peptides indicating that these proteins have a considerable sequence homology. Thus, various pieces of evidence indicate that P43 and the alpha-chain of pyruvate dehydrogenase are very similar if not identical. The possible implication of a glutamate stimulated phosphorylation of pyruvate dehydrogenase for long term potentiation and epilepsy is discussed.
添加L-谷氨酸或几种柠檬酸循环中间产物可刺激大鼠大脑皮层P2组分中一种表观分子量为43,000的蛋白质（P43）的磷酸化，丙酮酸脱氢酶激酶的特异性抑制剂二氯乙酸可抑制这种磷酸化。对磷酸化P43和磷酸化丙酮酸脱氢酶α亚基的几种分子特性进行比较表明，这两种蛋白质通过相似的方法提取，具有相同的表观分子量和等电点。此外，在SDS存在下，用几种不同的蛋白酶消化这两种磷酸化蛋白质，产生的磷酸化肽模式相似，表明这些蛋白质具有相当程度的序列同源性。因此，各种证据表明，P43和丙酮酸脱氢酶的α链即使不完全相同也非常相似。文中讨论了谷氨酸刺激丙酮酸脱氢酶磷酸化对长时程增强和癫痫的可能影响。
