小麦应答低磷的钙依赖蛋白激酶基因TaCPK1A和TaCPK10的克隆和表达  

Cloning and Expression of Calcium-Dependent Protein Kinase Genes TaCPK1A and TaCPK10 in Response to Deficient-Pi in Wheat

作　　者：路文静[1] 李瑞娟[1] 李小娟[1] 郭程瑾[2] 谷俊涛[1] 肖凯[2] 

机构地区：[1]河北农业大学生命科学学院,河北保定071001 [2]河北农业大学农学院,河北保定071001

出　　处：《作物学报》2009年第9期1749-1754,共6页Acta Agronomica Sinica

基　　金：国家重点基础研究发展计划(973计划)前期项目(2007CB116209);河北省重点基础研究项目(08965525D);河北省自然科学基金(C2007000476)资助

摘　　要：采用构建富集磷胁迫特异表达基因cDNA差减文库、序列分析和cDNA-AFLP技术,鉴定了2个应答低磷胁迫的钙依赖蛋白激酶(CDPK)基因的表达序列标签。克隆、测序和比对结果表明,上述基因分别为TaCPK1A和TaCPK10。其cDNA长度分别为2129bp和1696bp,开放阅读框分别为1599bp和1281bp,分别编码532和426个氨基酸;具有CDPK的典型结构特征。系统进化分析表明,上述基因的核苷酸序列同源性低,分别来自不同的祖先。在对低磷胁迫的响应上,TaCPK1A在磷胁迫1～24h范围内根系内的表达水平不断增强,叶内表达水平在1h内明显被诱导,以后保持稳定;TaCPK10在相应磷胁迫时间范围根叶内的表达水平均呈低—高—低变化,在磷胁迫1h的表达被诱导,以后又逐渐降至胁迫前水平。TaCPK1A和TaCPK10对氮、钾胁迫没有应答响应。结果表明,CDPK在介导小麦低磷胁迫的信号转导中具有重要作用,小麦中存在两种或多种CDPK介导的磷酸化过程参与低磷信号的转导。Two expressed sequence tags （ESTs） of calcium-dependent protein kinase （CDPK） genes responding to deficient-Pi were identified from wheat （Triticum aestivum L.） cultivar Shixin 828 by subtractive suppression cDNA library and cDNA-AFLP approaches. The genes, TaCPKIA and TaCPKIO, contained the conserved domains of plant CDPK, were 2 129 bp and 1 696 bp in full length open reading frames of I 599 bp and 1 281 bp, encoding 532 and 426 amino acids, respectively. Phylogenetic analysis implied different ancestors of TaCPKIA and TaCPKIO because of their low identity of sequence. Under low-Pi condition, the expression level of TaCPKIA in roots was strongly inducible and reached the highest at 24 h after treatment, but that in leaves was induced in 1 h of treatment and maintained stably afterwards. The expression of TaCPKIO in roots and leaves both showed a pattern of low-high-low with the peak at 1 h of treatment, and then decreased to the level before treatment. No responses of TaCPK1A and TaCPKIO were observed to low-N and low-K stresses. Therefore, it is suggested that CDPK plays an important role in mediating phosphate-starvation signal in wheat. There are at least two phosphorylation reaction pathways for transduction of low-Pi signal, in which CDPKs are involved.

关 键 词：小麦(Triticum AESTIVUM L.) 钙依赖蛋白激酶 克隆 低磷胁迫 基因表达 

分 类 号：S512.1[农业科学—作物学]