水曲柳FmPAL基因的克隆及表达模式的分析

Cloning and Expression Pattern Analysis of PAL Gene in Fraxinus mandschurica

在催化苯丙烷类代谢途径的第一步反应中,苯丙氨酸解氨酶(PAL)起到关键酶和限速酶的作用,对植物有非常重要的生理意义。对水曲柳FmPAL基因进行了生物信息学以及表达模式分析,包括时空及其在NaCl、低温、IAA、ABA以及GA3处理下的特异性表达特征。结果表明,水曲柳FmPAL编码区全长为1674bp,编码557个氨基酸。FmPAL蛋白为稳定的亲水性蛋白,不存在信号肽但具有跨膜结构域。FmPAL基因与樟子松的PAL遗传距离比较近,说明它们亲缘关系比较近。FmPAL基因在新生枝和叶中相对表达量高于花、芽、叶柄等部位,并在新生枝中表达量最高,具有组织特异性。水曲柳新生枝和叶片中FmPAL基因在5月表达量相对较高。在非生物胁迫和激素诱导下,FmPAL基因的表达量随处理时间而改变,但其变化趋势不尽相同。在低温(4℃)、盐(NaCl)2种非生物胁迫下,FmPAL基因在处理12h后表达量最高,分别为对照组的34.3、24.3倍;在低温(4℃)和盐(NaCl)处理处理1h后,FmPAL基因表达量最低。FmPAL基因在脱落酸(ABA)处理1h后表达量最高,为对照组的11.9倍;生长素(IAA)处理12h后表达量最高,为对照组的37.2倍;赤霉素(GA)处理24h后表达量最高,为对照组的21.5倍;而FmPAL基因在脱落酸(ABA)、生长素(IAA)和赤霉素(GA)处理3h后表达量皆为最低。研究结果表明FmPAL基因响应非生物胁迫以及植物激素信号诱导。

In the first step of catalyzing the metabolic pathway of phenylpropanoids,phenylalanine ammonia lyase (PAL) plays a key role in enzymes and rate-limiting enzymes,and has important physiological significance for plants.This study analyzed the bioinformatics and expression pattern of FmPAL gene of Fraxinus mandshurica ,including time and space and in low temperature,NaCl,IAA,ABA and GA3 specific expression characteristics under treatment.The results showed that the coding region of FmPAL was 1 674 bp in length and encoded 557 amino acids.FmPAL protein is a stable hydrophilic protein.It has no signal peptide but has transmembrane domain.The genetic distances of FmPAL gene and Olea europaea var. sylvestris were relatively close,indicating that their genetic relationship was relatively close.The relative expressions of FmPAL gene in fresh branches and leaves were higher than those in flowers,buds and petiole,and it was the highest in the new fresh branches.The FmPAL gene in the fresh branches and leaves was relatively high in May.Under the abiotic stress and hormone induction,the expression level of FmPAL gene changed with the treatment time,but the change trend was not the same.Under the abiotic stresses of low temperature (4℃) and salt (NaCl),the expression level of FmPAL gene was the highest after treatment for 12 hours,which was 34.3 times and 24.3 times of that of the control group,respectively.The expression of FmPAL gene was the highest after treatment with abscisic acid (ABA) for 1 hour,which was 11.9 times of that of the control group.The expression of FmPAL gene was the highest after auxin (IAA) treatment for 12 hours,which was 37.2 times of the control group;the expression level was the highest after gibberellin (GA) treatment 24 hours,which was 21.5 times of the control group;while the FmPAL gene was the lowest after 3 hours of treatment with abscisic acid (ABA),auxin (IAA) and gibberellic acid (GA).The results of this study indicated that the FmPAL gene was involved in abiotic stress and phytohormone signal induction.