Identification of 1-deoxy-D-xylulose-5-phosphate synthase and analysis on essential oil in Magnolia officinalis / 中草药

ABSTRACT

Objective: Based on the data of transcriptome sequencing of Magnolia officinalis, MoDXS1 and MoDXS2 genes were completed in detail by using bioinformatics methods. Methods: MoDXS1 and MoDXS2 genes were analyzed and predicted by the tools of bioinformatics in the following aspects physical and chemical characteristics of amino acid sequences, function domain, hyophobicity or hydrophilicity, secondary structure and tertiary structure of protein, molecular phylogenetic evolution, and so on; The expression levels of MoDXS1 and MoDXS2 were identified by real-time PCR. Results: ORF Finder indicated that MoDXS1 and MoDXS2 genes were full-length, and they all were unstable hydrophobic proteins; Structural domain of MoDXS1 and MoDXS2 showed high homology with other plants; The secondary structures all were hybrid architecture, and alpha helixes were the major motifs, tertiary structure of protein was predicted by Homology modeling; Sequence alignment that MoDXS family had relative close relationship to the DXS of Nicotiana tabacum, Salvia miltiorrhiza, and Arabidopsis thaliana; The results of evolutionary relationship analysis showed that MoDXS1 had relative close relationship to angiosperm, but MoDXS2 was clustered in a clade solely; The expression levels of DXS1 in M. officinalis and M. officinalis var. biloba were not significantly different, but the expression level of DXS2 in M. officinalis var. biloba was higher than that in M. officinalis. By applying the technique of GC-MS, the contents of major volatile components β-caryophyllene, β-caryophyllene oxide, and β-eudesmol in M. officinalis var. biloba are higher than those in M. officinalis. Conclusion: The results provide theoretical reference for studies on secondary metabolic regulation in terpenoid of M. officinalis.