Abstract:

To dissect the main biological processes and molecular mechanisms of Andrographis paniculate at the transcriptional level, the 60-day-old seedlings (seeds were used for production from Zhangzhou, Fujian) were chosen as experimental materials, and the initial sequence information of the full-length transcriptome of their roots, stems and the third true leaves (morphologically from top to bottom) were measured by the long read single-molecule sequencing technology. The initial sequences were dealt with screening, de-redundancy, correction, functional annotation and gene structure analysis. The results showed that the functions of Andrographis paniculate genes were mainly enriched in metabolic pathways, secondary metabolite synthesis pathways, and antibiotic synthesis pathways. The content of transcription factors directly involved in secondary metabolism, such as bHLH, bZIP, MYB and WRKY, ranked the top ten. Transcripts in the synthesis pathway of andrographolide precursors occurred alternative splicing, mainly in intron retention. Among them, one gene produced six mRNAs which promoters were altered. Overall, the secondary metabolism is the main biological process of Kalmegh, and related functional genes can participate in the process by combining abundant transcription factors and performing high-frequency alternative splicing.

Key words: Kalmegh, full-length transcriptome sequencing, secondary metabolic, transcription factors, alternative splicing, simple sequence repeats