响应低磷胁迫的小麦MDP激酶基因TaMPK1a-1的克隆和表达分析  

Cloning and Expression Analysis of A Wheat Mitogen-Activated Protein Kinase Gene of TaMPK1a-1 That Responding to Deficienct-Pi

作　　者：路文静[1] 李瑞娟[1] 王效颖[2] 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：《中国农业科学》2009年第7期2601-2607,共7页Scientia Agricultura Sinica

基　　金：科技部"973"前期(2007CB116209);河北省应用基础研究计划(08965525D);河北省自然基金(C2007000476)

摘　　要：【目的】蛋白磷酸化在介导非生物逆境信号的转导中具有重要作用。以笔者在低磷胁迫下鉴定的小麦促分裂原活化蛋白激酶(MAP激酶)基因TaMPK1a-1为基础,开展该基因应答低磷逆境分子特征的研究。【方法】利用cDNA-AFLP技术,鉴定特异上调表达的MAP激酶基因TaMPK1a-1。采用生物信息学技术研究基因结构和编码蛋白特征,采用半定量RT-PCR技术研究TaMPK1a-1应答低磷胁迫逆境的分子特征。【结果】TaMPK1a-1 cDNA长度为2170bp,开放阅读框为1737bp,编码578个氨基酸残基。TaMPK1a-1含有2个参与双重磷酸化作用的TEY和TDY基序。在正常供磷条件下,磷高效品种石新828和磷低效品种冀7369根叶中均检测不到TaMPK1a-1的转录本;低磷处理下,TaMPK1a-1的表达在上述品种的根叶中均受到明显诱导。与冀7369相比,低磷条件下石新828根叶中TaMPK1a-1的转录本明显增多。【结论】TaMPK1a-1级联转导途径不仅影响着小麦对低磷信号的响应,而且对于增强小麦适应低磷胁迫的能力中也可能具有重要作用。[Objective] Protein phosphorylation plays an important role in mediating the abiotic stress signal transduction in plants. In this study, the responding characterizations of TaMPKla-1, a novel mitogen-activated protein kinase gene identified under deficient-Pi condition in wheat, were elucidated. [Methods] TaMPKla-1 with a up-regulated expression pattern under deficienct-Pi was identified based on cDNA-AFLP approach. The gene structure and the protein features were analyzed by bioinformatics tools. The responding characterizations of TaMPKla-1 to deficient-Pi were explored based on semi-quantitative RT-PCR method. [Results] The cDNA length of TaMPK1a-1 was 2 170 bp, containing an open reading frame of 1 737 bp and encoding a polypeptide of 578-aa. There were two dual phosphorylation sites in TaMPKla-1, including one TEY motif and one TDY motif. Under normal Pi supply condition （2 mmol·L^-1 Pi）, no transcripts of TaMPK1a-1 in roots and leaves of two wheat cultivars, including high-P efficiency cultivar Shixin8282 and low-P efficiency cultivar Ji7369, were detected. Under deficient-Pi （20 μmol·L^-1 Pi） condition, the expression of TaMPK1a-1 in the roots and the leaves of above two cultivars were all induced. Compared with Ji7369, the transcripts of TaMPKla-1 in roots and leaves in Shixin828 under deficient-Pi condition were much strongly enhancement. [Conclusion] The cascade pathway of TaMPK1a-1 in wheat not only affects the responding ability to low-Pi stress signal, but also possibly plays an important role in regulation of plant P use efficiency under deficient-Pi condition.

关 键 词：小麦(Triticum aestivutn L.) 促分裂原活化蛋白激酶基因 磷胁迫 克隆 表达 

分 类 号：S512.1[农业科学—作物学]