烟草幼苗两种钙调素结合蛋白激酶的活性调节及基因表达  

Gene Expression and Activity Regulation of Two Calmodulin Binding Protein Kinases in Tobacco Seedling

作　　者：华玮[1] 李荣俊[2] 梁述平[2] 吕应堂[2] 

机构地区：[1]中国农业科学院油料作物研究所农业部重点实验室,武汉430062 [2]武汉大学生命科学学院植物发育生物学教育部重点实验室,武汉430072

出　　处：《植物生理与分子生物学学报》2005年第3期305-310,共6页Journal Of Plant Physiology and Molecular Biology

基　　金：国家自然科学基金(No.30070078);中国农业科学院油料所所长基金资助。~~

摘　　要：在体外条件下,烟草两种钙调素结合蛋白激酶(NtCBK1与NtCBK2)自磷酸化活性的最适pH分别是7.5和8;Mg2+离子浓度对两种激酶自磷酸化活性影响比Na+离子大。Northern杂交结果显示:两基因在花和叶中都有大量表达,但在根和茎中NtCBK1的表达量明显多于NtCBK2;高盐处理会引起NtCBK1基因表达量升高,而高温、低温和干旱处理对该基因表达没有影响,说明NtCBK1参与植物体内盐诱导的信号转导。Two differentc almodulin-binding proteinkinase cDNAs (NtCBK1/2) have been isolatedfrom tobacco. To understand the CBK protein ac-tivity regulation, we compared the activity regula-tion of NtCBK1 and NtCBK2 by pH, Mg2+ con-centration and Na+ concentration. We found theautophosphorylation of NtCBK1/2 reached themaximum in pH 7.5 and 8 respectively (Figs.1A and2A); Mg2+ and Na+ shown different effects on theactivity of NtCBKs, high and low Mg2+ concentra-tions both inhibited the activity of NtCBKs, but Na+had little effect on the kinase activity (Figs.1 and 2).In addition, to obtain further insight about the physi-ological roles of individual NtCBKs, we detectedthe expression profiles of CBKs. The results revealeddifferent patterns of expression of NtCBK1 andNtCBK2. Both are largely expressed in leaf and flower; but in stem and root, NtCBK1 gene hadstronger expression than NtCBK2 (Fig.3). NtCBK2expression was induced by GA treatment, whileNtCBK1 expression remainedu nchanged under GAtreatment (Fig.4B). Expression of both NtCBK1 andNtCBK2 increased in response to salt stress, theformer to a greater extent, and both expressions didnot change under high/low temperature, drought,NAA and ABA treatments (Fig.4).

关 键 词：钙调素结合蛋白激酶 自磷酸化 基因表达 NORTHERN杂交 

分 类 号：S572[农业科学—烟草工业]