二氮嗪预处理心肌细胞后磷酸化蛋白质组差异表达的初步研究

Comparative phosphoproteome analysis of cardiomyocytes preconditioned by diazoxide

目的:分析鉴定二氮嗪(DZ)预处理后心肌细胞磷酸化蛋白质组的表达变化。方法:采用培养成年大鼠心肌细胞模型,分别提取、富集对照组和DZ(200μmol/L)预处理组心肌细胞的磷酸化蛋白质,用双向电泳和质谱技术对两组中差异表达的磷酸化蛋白质进行分离和鉴定。结果:DZ预处理后,分子伴侣包含蛋白TCP-1和假拟蛋白XP_346548的磷酸化程度增加(P<0.05);而糖调节蛋白94kD、依钙(结合)蛋白I和铁蛋白的磷酸化程度减弱(P<0.05)。结论:DZ预处理后,心肌细胞内的一些蛋白质发生了磷酸化修饰改变,它们可能介导Mi-toKATP通道开放后预处理心肌保护效应的发挥。

AIM： To analyze and identify the phosphoproteins associated with diazoxide preconditioning. METHODS： Proteomics technique was used to investigate the changes of phosphoprotein after diazoxide preconditioning. Adult rat ventricular myocytes were pretreated in the presence and absence of 200μmol/L diazoxide for 10 min. Phosphoproteins prepared and enriched respectively from control and diazoxide pretreated groups were then separated by two - dimensional （2D） gel electrophoresis and stained with sliver staining kit. Phosphoproteins of interest were further identified by mass spectrometry. RESULTS ： Associated with diazoxide preconditioning, the proteins of chaperonin containing TCP - 1 and hypothetical protein XP_346548 were phosphorylated significantly. The proteins of 94 kD glucose - regulated protein, calpactin I heavy chain and ferritin were dephosphorylated markedly （ P 〈 0. 05 ）. CONCLUSION： These findings suggest that cardiomyocytes undergo significant posttranslational modification via phosphorylation in a multitude of proteins in response to diazoxide preconditioned signaling, which may mediate myocardioprotection signaling downstream mitochondrial staining dish KATP channel induced by ischemic preconditioning.