澳洲香水石斛花香成分及DeTPS6的克隆与表达OA北大核心CSTPCD

Floral aroma is a key trait for evaluating the commercial value of Dendrobium.To unveil the formation mechanism of floral aroma in Dendrobium Aozhouxiangshui during different florescences,the change of volatile compounds and its relation to terpenoid synthase gene expression were investigated by headspace solid-phase microextraction-gas chromatography-mass spectrometry(HS-SPME-GC-MS),transcriptomes,and PCR technology.The results showed that a total of 17 volatile compounds were identified.Among them,the contents of 1,4-dimethoxybenzene,alpha-pinene,and phenylethyl alcohol were relatively high.The release of floral aroma during the blooming stage exhibited significant circadian rhythm and tissue specificity.Based on RNA sequencing analysis,77 differentially expressed genes related to terpenoid synthesis were screened,and the full length of DeTPS6(1 749 bp)was successfully cloned.DeTPS6 contained the conserved domains of the terpenoid synthase family and belonged to the TPS-b subfamily.Subcellular localization analysis revealed that DeTPS6 was localized in the cytoplasm.Quantitative real-time PCR(qRT-PCR)analysis showed that DeTPS6 was highly expressed at the flowering stage with a significant circadian rhythm,which also showed a positive correlation with aroma components content.This study lays the theoretical basis for exploring the biological functions of DeTPS6.