IAA对小麦胚芽鞘质膜蛋白磷酸化的影响  

The Effect of IAA on Phosphorylation of Plasma Proteins in Wheat Coleoptiles

作　　者：吴海明[1] 王宁宁[1] 于自然[1] 朱亮基[1] 

机构地区：[1]南开大学生物化学与分子生物学系,天津300071

出　　处：《植物生理学报（0257-4829)》1999年第4期375-380,共6页Acta Phytophysiologica Sinica

基　　金：国家自然科学基金

摘　　要：磷酸化／ 脱磷酸化机制是众多信号转导过程中的重要环节，很多信号物质被细胞受体识别后引发蛋白激酶和蛋白磷酸酶活性变化，通过磷酸化／ 脱磷酸化进一步调节多种酶活性而产生各种生理效应。在对生长素ＩＡＡ 的信号转导的研究中，发现ＩＡＡ 处理的小麦胚芽鞘质膜蛋白中蛋白激酶的活性和蛋白磷酸化程度都发生改变，并找到两种受到调节的蛋白激酶。钙离子通道抑制剂ＬａＣｌ３ 阻断了ＩＡＡ 的这种作用，表明Ｃａ２＋参与了ＩＡＡ的信号转导过程。Protein kinases and protein phosphatases play key roles in signal transduction. Many factors regulate enzyme activities by changing the phosphorylation level of them. Protein kinase activity was observed in plasma membrane of wheat coleoptiles (Fig. 1). Activity of this kinase is Ca 2+ dependent (Fig. 2). Treating with IAA increased the kinase activity (Fig. 3). The phosphorylation of proteins with molecular weight 132,100,87,72,50 and 35 kD was enhanced (Fig. 4). IAA also enhanced the autophosphorylation of protein kinases with MW 125 and 89 kD (Fig. 5). LaCl 3, as an inhibitor of calcium ion channel, diminished the influences of IAA. It seems possible that Ca 2+ dependent protein kinase functions in calcium regulated signal transduction processes in IAA induced elongation of wheat coleoptiles through their responses to changes in concentration of cytosolic calcium.

关 键 词：小麦 胚芽鞘 蛋白磷酸化 钙离子通道 生长素 

分 类 号：Q942.6[生物学—植物学] Q946.885.1