transcriptome assembly and metabolomic analysis of three tissue types in .

OBJECTIVE

The barks, leaves, and branches of have been historically used as a traditional Chinese medicine, spice, and food preservative, in which phenylpropanoids are responsible compounds. However phenylpropanoid biosynthesis pathways are not clear in . We elucidated the pathways by descriptive analyses of differentially expressed genes related to phenylpropanoid biosynthesis as well as to identify various phenylpropanoid metabolites.

METHODS

Chemical analysis, metabolome sequencing, and transcriptome sequencing were performed to investigate the molecular mechanisms underlying the difference of active components content in the barks, branches and leaves of .

RESULTS

Metabolomic analysis revealed that small amounts of flavonoids, coumarine, and cinnamaldehyde accumulated in both leaves and branches. Transcriptome analysis showed that genes associated with phenylpropanoid and flavonoid biosynthesis were downregulated in the leaves and branches relative to the barks. The observed differences in essential oil content among the three tissues may be attributable to the differential expression of genes involved in the phenylpropanoid and flavonoid metabolic pathways.

CONCLUSION

This study identified the key genes in the phenylpropanoid pathway controling the flavonoid, coumarine, and cinnamaldehyde contents in the barks, branches and leaves by comparing the transcriptome and metabolome These findings may be valuable in assessing phenylpropanoid and flavonoid metabolites and identifying specific candidate genes that are related to the synthesis of phenylpropanoids and flavonoids in .