Correlation analysis of the taxane core functional group modification, enzyme expression, and metabolite accumulation...

Metabolomic and transcriptomic profiling data were obtained and integrated to elucidate the crucial network controls on taxol and its precursor biosynthesis during the taxane core functionalization within methyl jasmonate (MJ)-induced Taxus chinensis cells. Twelve metabolites were identified using liquid chromatography-electrospray ionization-mass spectrometry. These metabolites contain taxol (paclitaxel), baccatin III (B-III) and its analogs, a group structurally bearing multiple free hydroxyls (TAX), and another group of multiple acyl taxanes (MAT), including taxuyunnanine C (TC) and its analogs. The metabolomic profile showed a higher increase in TAX than in MAT. Particularly, the ratio of B-III and taxol to the total taxane content increased more significantly in TAX than in MAT. The MAT proportion did not significantly change, although they are predominant components in cell cultures compared with TAX. Quantitative real-time polymerase chain reaction (qRT-RCR) was used to determine the transcription level of 20 genes, among which 11 were reported responsible for taxol biosynthesis and 9 were obtained from our previous transcriptomic data. The total expression levels of hydroxylase after 24 h and 6 days were higher than those of acylase. The principal component analysis (PCA) results validated the metabolomic analysis data, indicating that hydroxylation was more crucial than acylation for controlling the flux toward TAX biosynthesis. Furthermore, the PCA contribution comparison showed that two undefined genes of OHX1 and ACX3 might have good potential in TAX upregulation and MAT downregulation. To the best of our knowledge, this study provides the first experimental evidence on the contribution of total hydroxylation to taxane biosynthesis.