Molecular Cloning and Functional Analysis of DXS and FPS Genes from Zanthoxylum bungeanum Maxim

Abstract

Zanthoxylum bungeanum Maxim. (Z. bungeanum) has attracted attention for its rich aroma. The aroma of Z. bungeanum is mainly volatile terpenes synthesized by plant terpene metabolic pathways. However, there is little information on Z. bungeanum terpene metabolic gene. In this study, the coding sequence of 1-deoxy-D-xylulose-5-phosphate synthase (DXS) and farnesyl pyrophosphate synthase (FPS) were cloned from Z. bungeanum cv. ‘Fengxiandahongpao.’ ZbDXS and ZbFPS genes from Z. bungeanum with CDS lengths of 2172 bp and 1029 bp, respectively. The bioinformatics results showed that Z. bungeanum was closely related to citrus, and it was deduced that ZbFPS were hydrophilic proteins without the transmembrane domain. Subcellular localization prediction indicated that ZbDXS was most likely to be located in chloroplasts, and ZbFPS was most likely to be in mitochondria. Meanwhile, the 3D protein structure showed that ZbDXS and ZbFPS were mainly composed of α-helices, which were folded into a single domain. In vitro enzyme activity experiments showed that purified proteins ZbDXS and ZbFPS had the functions of DXS enzyme and FPS enzyme. Transient expression of ZbDXS and ZbFPS in tobacco significantly increased tobacco’s terpene content. Moreover, ZbDXS and ZbFPS were expressed in different tissues of Z. bungeanum, and the relative expression of the two genes was the highest in fruits. Therefore, this suggests that ZbDXS and ZbFPS are positively related to terpene synthesis. This study could provide reference genes for improving Z. bungeanum breeding as well as for the Rutaceae research.

Genotype-Specific Expression of Selected Candidate Genes Conferring Resistance to Leaf Rust of Rye (Secale cereale L.)

“…The last one, the DXS gene, encodes the first and rate-limiting enzyme in the plastidial methylerythritol phosphate pathway, which produces isopentenyl diphosphate and its isoform dimethylallyl diphosphate as terpenoid biosynthesis precursors and plays essential roles in many physiological processes, including defence responses to pathogens [ 37 , 38 ]. However, there are no reports describing a relationship between DXS genes and plant responses to LR infections.…”

Volatile metabolomics and transcriptomics analyses provide insights into the mechanism of volatile changes during fruit development of ‘Ehime 38’ (Citrus reticulata) and its bud mutant

“…Monoterpenes constituted the largest portion of total volatiles in both WT and MT, and the expression of most genes in MEP pathway were positively correlated with the level of most DAVs (including d-limonene) and most genes in MVA pathway were negatively correlated. DXS is the first key rate-limiting enzyme in MEP pathway, and overexpressing DXS significantly enhances monoterpenes content in Nicotiana benthamiana ( Nieuwenhuizen et al., 2015 ; Tian et al., 2022 ). In the pulps of MT, DXS1 was consistently expressed at higher levels than that in WT during fruit development.…”

Transcriptome Analyses Reveal the Aroma Terpeniods Biosynthesis Pathways of Primula forbesii Franch. and the Functional Characterization of the PfDXS2 Gene

“…For instance, the relative expression of TcDXS in different tissues of Taxus chinensis followed this trend: tender petioles > leaves > barks > roots > stems [ 63 ]. ZbDXS ( Zanthoxylum bungeanum ) has the highest expression in fruits, followed by leaves, and the lowest expression in flowers [ 64 ]. These studies have shown that the expression of DXS genes is different in different plants, and different genes in the DXS family are responsible for the biosynthesis of different terpenoids.…”