Integrated transcriptomic and metabolomic analyses reveal the ABC transporter-related genes and metabolites involved in seed aging of Platostoma palustre (Blume) A. J. Paton

Platostoma palustre (Blume) A. J. Paton (or Mesona chinensis Benth.), a traditional medicinal and edible plant in China, possesses significant economic and market potential. To investigate the underlying mechanism of seed aging in P. palustre, we utilized artificial aging technology to induce seed aging and assessed seed viability. Furthermore, we employed transcriptome and metabolome sequencing technologies to analyze gene expression and metabolic alterations in artificially aged seeds. The results showed that the germination rate, germination potential, and germination index of the P. palustre seeds decreased significantly after the aging treatment. Transcriptome analysis identified 2,127 differentially expressed genes (DEGs), consisting of 1,623 up-regulated and 504 down-regulated genes. Metabolomic analyses uncovered that a total of 1,919 metabolites were identified under positive ion mode (957) and negative ion mode (962). In total, 747 differentially expressed metabolites (DEMs) were identified, including 362 up-regulated and 385 down-regulated metabolites. An integrative analysis of transcriptome and metabolome indicated that only one pathway (ABC transporters) was significantly enriched in both DEMs and DEGs, and this pathway included 9 DEMs (Deoxyuridine, L-Glutamine, Sparfloxacin, L-Threonine, L-Histidine, Uridine, Guanosine, Ciprofloxacin, and D-Sorbitol) and 6 DEGs (Mesona_chinensis0082240.1, Mesona_chinensis0452530.1, Mesona_chinensis0457550.1, Mesona_chinensis0440370.1, Mesona_chinensis0324680.1, and Mesona_chinensis0233350.1). Further network analyses showed correlations between the 5 DEGs (except for Mesona_chinensis0324680.1) and 9 DEMs. It was inferred that the ABC transporters pathway and its related genes and metabolites might play an important role in seed aging in P. palustre. The current study laid the foundation for an in-depth investigation of the aging mechanism and safe storage of P. palustre seeds.