Abstract:To understand the biosynthesis pathway of flavonoids in the medicinal plant Polygonatum cyrtonema and provide molecular data for the study on anabolism pathway and regulatory mechanism of flavonoids in Polygonatum plant, next-generation sequencing technique was emloyed to perform transcriptome sequencing on the rhizome of P. cyrtonema at development stage of 3 and 9 months. The results showed that a total of 73 218 unigenes were obtained by de novo transcriptome assembly, of which 35 511 were annotated. Eighty-three unigenes were identified from the transcriptome database, which encoded 18 key enzymes associated with flavonoids biosynthesis. Among the transcription factors expressed in rhizome of P. cyrtonema seedlings, bHLH was the main type, followed by ERF, MYB-relaed, C2H2 and NAC. Analysis of expression of 18 key enzymes based on FPKM showed that 7 were obviously up-regulated, 3 obviously down-regulated and 8 stably expressed with increasing flavonoid content in rhizome of P. cyrtonema seedlings. RT-qPCR analysis further verified the reliability of gene expression from FPKM. This present study provide reference for further explore on the molecular mechanism on biosynthesis and accumulation of flavonoids in Polygonatum plant.
