背景:花可以是用于制造具有高经济价值的物质的精油的来源。乙烯反应因子(ERF)基因家族在调节植物次生代谢产物的生物合成中起关键作用。然而,直到现在,关于ERF转录因子(TFs)在花萜类生物合成中的参与知之甚少。
结果:在这项研究中,一种芳香的植物,法国报春花。,以PfERF106为研究材料,探讨其对萜类化合物生物合成的关键调节作用。PfERF106编码一个IXb组ERF转录因子,在forbesii花中表现出一致的表达趋势,并被外源乙烯转录诱导。PfERF106的瞬时沉默显著降低了关键花萜烯的相对含量,包括(z)-β-辛烯,Sabinene,β-pine烯,γ-萜品烯,芳樟醇,emophilene,α-紫罗兰酮,和α-松油醇.相比之下,PfERF106在转基因烟草中的组成型过表达显着增加了关键花萜烯的相对含量,包括顺式-3-己烯-1-醇,芳樟醇,石竹烯,cembrene,还有巩膜.PfERF106沉默的植物和空载体对照植物的花瓣的RNA测序显示,有52,711个表达的单基因和9,060个差异表达的基因(DEGs)。KEGG注释分析显示,DEGs被富集参与次级代谢生物合成途径,包括单萜和二萜合成。值得注意的是,10个下调的DEGs被确定为PfERF106的下游靶基因,影响紫菜中萜类化合物的生物合成。
结论:本研究表征了PfERF106对萜类化合物生物合成的关键正调节作用,表明了优质的遗传资源,可用于改善紫苏的香气。因此,本研究推进了芳香物质代谢工程的人工精确定向调控。
BACKGROUND: Flowers can be a source of essential oils used in the manufacture of substances with high economic value. The ethylene response factor (ERF) gene family plays a key role in regulating secondary metabolite biosynthesis in plants. However, until now, little has been known about the involvement of ERF transcription factors (TFs) in floral terpenoid biosynthesis.
RESULTS: In this study, an aromatic plant, Primula forbesii Franch., was used as research material to explore the key regulatory effects of PfERF106 on the biosynthesis of terpenoids. PfERF106, which encodes an IXb group ERF transcription factor, exhibited a consistent expression trend in the flowers of P. forbesii and was transcriptionally induced by exogenous ethylene. Transient silencing of PfERF106 in P. forbesii significantly decreased the relative contents of key floral terpenes, including (z)-β-ocimene, sabinene, β-pinene, γ-terpinene, linalool, eremophilene, α-ionone, and α-terpineol. In contrast, constitutive overexpression of PfERF106 in transgenic tobacco significantly increased the relative contents of key floral terpenes, including cis-3-hexen-1-ol, linalool, caryophyllene, cembrene, and sclareol. RNA sequencing of petals of PfERF106-silenced plants and empty-vector control plants revealed 52,711 expressed unigenes and 9,060 differentially expressed genes (DEGs). KEGG annotation analysis revealed that the DEGs were enriched for involvement in secondary metabolic biosynthetic pathways, including monoterpene and diterpene synthesis. Notably, 10 downregulated DEGs were determined to be the downstream target genes of PfERF106 affecting the biosynthesis of terpenoids in P. forbesii.
CONCLUSIONS: This study characterized the key positive regulatory effects of PfERF106 on the biosynthesis of terpenoids, indicating high-quality genetic resources for aroma improvement in P. forbesii. Thus, this study advances the artificial and precise directional regulation of metabolic engineering of aromatic substances.