玉米脱落酸受体ZmPYL9基因的克隆及功能探究

Cloning and Function Analysis of Maize Abscisic Acid Receptor ZmPYL9 Gene

脱落酸(ABA)参与植物发育过程以及调控多种非生物胁迫的适应性,PYL基因作为ABA受体,直接影响ABA的生物合成。为了探究玉米中PYL家族基因的功能,克隆了一个ZmPYL 9基因,该基因编码197个氨基酸;物种同源蛋白质系统进化分析发现,ZmPYL9与高粱同源蛋白相似度甚高,且具有相同的保守基序;启动子顺式作用元件分析发现,ZmPYL 9基因ATG上游2000 bp区域含有多种激素应答相关的结合位点;ZmPYL 9基因组织表达分析结果表明,该基因属于组成型表达,在胚乳中高度表达。ZmPYL 9基因正向响应外源ABA诱导,恢复正常培养后,该基因表达量急速下降且低于CK;但是ZmPYL 9基因受PEG和PEG+ABA负向诱导,且在PEG+ABA胁迫下该基因表达量高于PEG胁迫下,恢复正常培养后,2种胁迫下该基因的表达量均表现上升趋势。说明ZmPYL 9基因响应干旱胁迫和ABA诱导,且ABA可以提高干旱胁迫下该基因的表达量。

Abscisic acid(ABA)participates in plant development and regulates the adaptability of various abiotic stresses.The PYL gene acts as an ABA receptor and directly affects the biosynthesis of ABA.In order to explore the function of the PYL family gene in maize,a ZmPYL 9 gene was cloned,encoding 197 amino acids.Evolutionary analysis of homologous proteins revealed that ZmPYL9 was highly homologous to sorghum homologous proteins and had the same conserved motif.Analysis of the promoter cis-acting element revealed that the 2000 bp upstream of the ATG of the ZmPYL 9 gene contained multiple hormone-responsive binding sites.The tissue expression analysis of ZmPYL 9 gene indicated that the gene was constitutively expressed and highly expressed in endosperm.The positive response of ZmPYL 9 gene was induced by exogenous ABA,and the expression of this gene decreased rapidly and was lower than CK level after returning to normal rehydration culture.The ZmPYL 9 gene was negatively induced by PEG and PEG+ABA,and the gene expression was higher than PEG stress under PEG+ABA stress.However,after normal rehydration,the expression of this gene under both stresses showed an upward trend.These indicate that ZmPYL 9 gene responds to drought stress and ABA induction,and ABA can increase the expression of this gene under drought stress.