Fig. 3

Organ-specific analysis of the levels of the enzyme-coding genes and the metabolites within the sterol biosynthetic pathway of Bletilla striata. A The previously reported biosynthetic pathway of sterols [17]. Based on the transcriptome assembly annotated by the KEGG database, 11 enzymes could find their coding genes (colored within the pathway) based on the EC numbers. SQS: squalene synthase, [EC:2.5.1.21]; AltSQE: alternative squalene epoxidase, [EC:1.14.19.-]; LAS: lanosterol synthase, [EC:5.4.99.7]; CAS1: cycloartenol synthase, [EC:5.4.99.8]; SMT1: sterol 24-C-methyltransferase, [EC:2.1.1.41]; SMO1: plant 4,4-dimethylsterol C-4alpha-methyl-monooxygenase, [EC:1.14.18.10]; CPI1: cycloeucalenol cycloisomerase, [EC:5.5.1.9]; CPY51: sterol 14alpha-demethylase, [EC:1.14.14.154], [EC:1.14.15.36]; FK: Delta14-sterol reductase, [EC:1.3.1.70]; HYD1: cholestenol Delta-isomerase, [EC:5.3.3.5]; SMT2: 24-methylenesterol C-methyltransferase, [EC:2.1.1.143]; SMO2: plant 4alpha-monomethylsterol monooxygenase, [EC:1.14.18.11]; STE1: Delta7-sterol 5-desaturase, [EC:1.14.19.20]; DWF5: 7-dehydrocholesterol reductase, [EC:1.3.1.21]; DWF1: Delta24-sterol reductase, [EC:1.3.1.72], [EC:1.3.1.-]; CYP710A: sterol 22-desaturase, [EC:1.14.19.41]. B A heatmap showing the expression patterns of the enzyme-coding genes in roots, tubers and leaves of B. striata. For some of the enzymes, there are two or more coding genes. After z-score normalization, the heatmap was drawn at a log2 scale from -3 to +3. C A heatmap showing the levels of the metabolite in three organs. Based on metabolite quantification, the heatmaps were drawn at a log2 scale from -3 to +2. Delta8,14-Sterol: C11508; 5-Dehydroavenasterol: C15783