栀子TPS基因家族鉴定及与萜类物质代谢的相关性分析

Identification of TPS Genes Family in Gardenia jasminoides and Its Relationship with Terpenoid Metabolism

TPS基因家族是萜类化合物合成的末端关键酶,在栀子花香的形成中起重要作用。为了明确栀子TPS基因家族成员的基本特征,利用生物信息学方法对栀子TPS基因进行家族成员鉴定;通过外源激素喷施试验进行转录组测序,结合顶空固相微萃取和气相色谱-质谱联用技术,分析不同外源激素浓度下栀子花朵TPS基因家族成员表达水平和代谢物含量变化关系。结果表明:从栀子基因组中共鉴定获得GjTPS家族成员41个,编码氨基酸380~849个,含有外显子5~15个不等,GjTPS家族成员定位在叶绿体中,并且不均匀地分布在10条染色体上;共线性分析表明栀子与其同科植物中粒咖啡的TPS基因有更近的亲缘关系。系统发育分析结果显示GjTPS基因分为5个亚家族,TPS-a、TPS-b亚家族包含了大多数GjTPS家族成员。GjTPS家族成员的大多数启动子顺式作用元件在植物激素响应类别中,并且包含MYC基序的茉莉酸甲酯响应元件是其中大类;通过转录组数据得到GjTPS02、GjTPS12、GjTPS14、GjTPS20、GjTPS21、GjTPS22这6个基因在各处理的表达量较高。对基因表达量与萜类物质含量变化进行相关性分析,发现1.25 mmol·L^(-1)的茉莉酸甲酯有助于栀子TPS基因家族成员的表达及萜类物质的释放;GjTPS12、GjTPS14、GjTPS20、GjTPS21、GjTPS22这5个基因可能参与栀子花香调控。本研究结果可为后续栀子TPS基因家族功能特性研究提供借鉴。

Terpene synthase is a key enzyme in the synthesis of terpenoid compounds in Gardenia jasminoides and plays a key role in the formation of aromas.In order to clarify the basic characteristics of TPS Gene family members of G.jasminoides,the TPS gene family members of G.jasminoides were identified by bioinformatics method.We then used exogenous hormone spray test combined with transcriptomic approach to analyze the differential gene expression patterns of TPS gene family members in the flower of G.jasminoides.The contents of terpenoid compounds in flower of G.jasminoides at different developmental exogenous hormone spray were also measured by using head solid-phase micro-extraction combined with gas chromatography-mass spectrometry.The results showed that 41 members of GjTPS family were identified from genome database of G.jasminoides,encoding 380 to 849 amino acids and containing 5 to 15 exons.The members of GjTPS family were localized in chloroplasts and distributed unevenly on 10 chromosomes.Collinearity analysis revealed that TPS gene in G.jasminoides has a closer relationship with the TPS gene of Coffee canephora.Phylogenetic Analysis showed that GjTPS genes were divided into 5 subfamilies,and TPS-a and TPS-b subfamilies contained most of the members of GjTPS family.Most of cis-acting regulatory elements GjTPS promoters were in the Plant hormone response category,and the Methyl jasmonate Response element containing MYC motif is a large category among them.The transcriptome date showed that GjTPS02,GjTPS12,GjTPS14,GjTPS20,GjTPS21,GjTPS22 were highly expressed in all treatments.The correlation between gene expression and terpenoid content was analyzed,and it was found 1.25 mmol·L~(-1) methyl jasmonate contributes to gene expression of TPS family members and terpenoid release of G.jasminoides.GjTPS12,GjTPS14,GjTPS20,GjTPS21,GjTPS22 might be involved in the regulation of aroma formation in G.jasminoides.These result can provide reference for the subsequent function characteristics study of TPS gene family of G.jasminoides.