茉莉花PAL基因家族的多基因组鉴定与表达分析

Multi-genomic identification and expressional analysis of PAL gene family in Jasminum sambac

为深入探究茉莉花PAL基因家族的功能及在香气成分形成中的作用,本研究以福州单瓣茉莉花、双瓣茉莉花和重瓣茉莉花基因组数据为基础,利用生物信息学方法及实时荧光定量PCR技术,对JsPAL基因家族进行多基因组分析。结果表明,在单瓣茉莉花、双瓣茉莉花和重瓣茉莉花全基因组中分别鉴定出4个、1个和4个PAL家族基因,JsPAL家族成员均具有丙氨酸-丝氨酸-甘氨酸(Ala-Ser-Gly)组成的三肽活性中心。共线性分析发现单瓣茉莉花、重瓣茉莉花和拟南芥的PAL基因间的共线性关系与双瓣茉莉花相比更强;系统发育树分析结果显示,JsPAL基因家族分布在2个亚家族中。JsPAL基因启动子区域存在大量与胁迫响应、激素响应、光响应和植物生长相关的顺式调控元件。荧光定量分析结果表明,JsPAL在茉莉花组织中存在特异性表达,多数JsPAL在花中的相对表达量高于其他组织;大多数JsPAL基因在福州单瓣茉莉花中的相对表达量高于双瓣茉莉花;福州单瓣茉莉花中SP_JsPAL2、SP_JsPAL4、MP_JsPAL1和MP_JsPAL3在其花朵预开放期(F3)的相对表达量显著高于其他时期,双瓣茉莉花中DP_JsPAL1在F3阶段的相对表达量也较高;SP_JsPAL1和SP_JsPAL2与2-苯乙醇和苯乙醛含量呈显著正相关,其中SP_JsPAL1还与苯甲醛含量呈显著正相关。说明,JsPAL可能在茉莉花的发育中起重要作用,SP_JsPAL2、SP_JsPAL4、MP_JsPAL1、MP_JsPAL3和DP_JsPAL1可能对福州单瓣茉莉花、双瓣茉莉花的香气成分形成具有重要的调控作用,SP_JsPAL1可能对福州单瓣茉莉鲜灵香气的形成具有重要作用。

To deeply investigate the function of the PAL gene family in Jasminum sambac and its role in the formation of aroma components,multi-genomic analysis of JsPAL gene family was conducted by bioinformatics methods and quantitative real-time PCR technology based on the genomic data of single-petal J.sambac,double petal J.sambac and multi-petal J.sambac from Fuzhou.The results showed that four,one and four PAL family genes were identified from the whole genome of single-petal J.sambac,double petal J.sambac and multi-petal J.sambac,respectively.All members of the JsPAL family had a tripeptide active center composed of alanine-serine-glycine(Ala-Ser-Gly).Collinearity analysis revealed that the collinear relation of PAL gene between single-petal J.sambac,multi-petal J.sambac and Arabidopsis thaliana was stronger compared with that of double-petal J.sambac.Analysis of phylogenetic tree showed that the JsPAL gene family was distributed in two subfamilies.There were many cis-regulatory elements that were related to stress response,hormone response,light response and plant growth in the promoter region of JsPAL genes.The results of fluorescence quantification analysis showed that JsPAL was specifically expressed in J.sambac tissues,and the relative expression of the majority JsPALs in flowers were higher than in other tissues.The relative expression of the majority JsPAL genes in Fuzhou single-petal J.sambac was higher than in double-petal J.sambac.The relative expressions of SP_JsPAL2,SP_JsPAL4,MP_JsPAL1 and MP_JsPAL3 in the pre-opening stage(F3)of Fuzhou single-petal J.sambac were higher than in other stages,the relative expression of DP_JsPAL1 in the F3 stage of Fuzhou double-petal Jasminum sambac was also high.SP_JsPAL1 and SP_JsPAL2 were positively correlated with 2-phenylethanol and phenylacetaldehyde contents,and SP_JsPAL1 was also positively correlated with benzaldehyde content.The results indicated that JsPALs may play an important role in flower development of J.sambac,and SP_JsPAL2,SP_JsPAL4,MP_JsPAL1,MP_JsPAL3 and DP_JsPAL1 may have important regulatory roles in the formation of aroma components in Fuzhou single-petal J.sambac and double-petal J.sambac.Moreover,SP_JsPAL1 may play an important role in the formation of fresh spirit aroma of Fuzhou single-petal J.sambac.