钙对小麦氮同化关键酶活性的影响及其与蛋白质磷酸化的关系

Effect of calcium on key enzymes of nitrogen assimilation and related to protein phosphorylation in wheat

摘要: 为探讨氮素同化机理 ,小麦幼苗经溶液培养 (培养液中不含Ca2+)至二叶一心后 ,在培养液中分别设置不同浓度的Ca2+ 、Ca2+专一性螯合剂EGTA以及Ca2+通道阻塞剂LaCl3进行处理 (进行EGTA和LaCl3处理时 ,培养液中Ca2+浓度为 1mmol/L)。结果表明 ,氮同化关键酶硝酸还原酶 (NR)、谷氨酰胺合成酶 (GS)活性同Ca2+/CaM依赖性蛋白激酶 (Ca2+/CaM PK)活性之间存在明显的相关性。说明钙作为第二信使所介导的信号转导中 ,蛋白质可逆磷酸化可能参与了对氮素同化的调节作用。

Abstract: The mechanism of nitrogen assimilation on green wheat seedlings through adding different concentration of Ca2+ 、Ca2+ specific chelator EGTA and blocker of Ca2+ channel LaCl3 in nutrient solution (when treated use of EGTA or LaCl3, there was 1mmol/L Ca2+ in nutrient solution) was studied. The results showed that there was significant correlation between the key enzymes of nitrogen assimilation (nitrate reductase, NR; glutamine synthetase, GS) and Ca2+/CaM dependent protein kinase (Ca2+/CaM PK).It indicated that reversible protein phosphorylation could take an important part in regulating the signal transduction pathway of calcium.