Abstract:

The purpose of this study is to elucidate main biological processes and molecular mechanism of flavonol synthesis in Abelmoschus manihot at the transcriptome level. Using the PacBio Sequel platform of high-throughput sequencing, the mixture of flowers, stems and leaves was taken as material, and the full-length transcriptome sequencing was performed by single-molecule real-time sequencing (SMRT) method. After quality control of the sequencing data, a total of 53925 high-quality transcripts were obtained, among which 53329 genes were annotated by public database. There were 16574 genes annotated in 138 pathways, of which the most annotated pathway was metabolic pathway (8556 genes), followed by biosynthesis pathway of secondary metabolites (4650 genes). In total, 10700 genes underwent alternative splicing events, and seven alternative splicing types were presented. Moreover, 3287 transcription factors were predicted, with the bHLH transcription factor family having the most genes. 5683 SSR loci were detected, and the AAG/CCT type was the most. 170 genes related to flavonol synthesis were identified, including 10 key glycosyltransferase genes, and CHS and F3H genes underwent intron-sparing variable splicing. This study revealed the overall level of transcriptome and flavonol biosynthesis pathway genes of A. manihot, and provided reference for its genetic improvement and functional gene mining and utilization.

Key words: Abelmoschus manihot, full-length transcriptome, flavonol, transcription factors, alternative splicing, SSR