玉米ZmCIPK20基因克隆及表达分析

Cloning and Expression Analysis of ZmCIPK20 Gene in Maize

CIPK蛋白激酶是植物非生物胁迫信号传导途径中的重要元件。为克隆玉米CIPK蛋白激酶基因ZmCIPK20全长c DNA序列,并分析其在盐胁迫下的表达模式,采用RT-PCR技术克隆基因,用生物信息学方法对获得的序列进行分析,采用荧光定量PCR方法研究ZmCIPK20在盐胁迫下的表达。本研究从玉米中克隆了一个编码CIPK蛋白激酶基因ZmCIPK20,该基因c DNA全长1 800 bp,5'-非编码区长203 bp,3'-非编码区长202 bp,编码区长1 395 bp,编码464个氨基酸,预测分子量为50.993 kD,等电点为8.55。推测的氨基酸序列中含有1个丝氨酸/苏氨酸蛋白激酶催化结构域S_TKc和1个NAF结构域。进化树分析发现,ZmCIPK20和SbCIPK分为一个分支。荧光定量PCR检测表明,ZmCIPK20基因受盐胁迫诱导表达,在根中下调表达,在叶中上调表达,说明玉米ZmCIPK20基因可能参与玉米对盐胁迫的应答,为揭示该基因的生物学功能提供依据。

Calcineurin B-like protein interacting protein kinases（CIPKs） are vital elements in plant abiotic stress signaling pathways.In order to clone full-length c DNA of CIPK gene ZmCIPK20 in maize and analysis of the expression of ZmCIPK20 gene response to salt stress.RT-PCR method was used to clone ZmCIPK20 genes,bioinformatics methods were used to analyze the obtained cDNAs sequence and the amino acid sequences were deduced,and fluorescence quantitative PCR method was used to investigate the expression of ZmCIPK20 under salt stress.the expression of ZmCIPK20 gene response to salt stress was analyzed by realtime fluorescence quantitative PCR.In this research,ZmCIPK20,a gene encoding for CIPK,was cloned from designated as ZmCIPK20 was isolated from maize.The full length ZmCIPK20 cDNA was 1 800 bp,including a 203 bp 5＇-UTR,a 202 bp3＇-UTR,and an ORF of 1 395 bp,and a 202 bp 3＇-UTR.This c DNA sequence encoded a polypepide of 464 amino acid residues,with a predicted molecular mass of 50.993 k D and a basic isoelectric point of 8.55,and there was a serine/threonine protein kinases catalytic domain S_TKc and a NAF domain in the encoded putativepredicted protein sequence.Phylogenetic tree analysis indicated that ZmCIPK20 clustered with Sb CIPK.Realtime fluorescence quantitative PCR analysis showed that the expression of ZmCIPK20 was induced by sal t stress,which wasdown-regulated in roots,but up-regulated in leaves.The expression patterns of ZmCIPK20 under salt stress suggested that this gene might be involved in the regulations response of maize to salt stress,which provided the basis for revealing the biological function of this gene