Integrative analysis of the metabolome and transcriptome reveals the mechanism of flower color and antioxidant capacity in three Syringa cultivars

Le résumé fourni par la source

Lilac plants ( Syringa spp.) are extensively valued in landscaping and human health for their colorful cultivars and significantly medicinal and edible properties. The current works mainly focus on the anthocyanidin-induced pigmentation or the flavonoid-driven antioxidant activity, respectively. Nevertheless, the genetic and metabolic panorama of flavonoids, especially the metabolic flux partitioning of anthocyanidin and other flavonoids, remains ambiguous in the Syringa vulgari s plants. In this study, integrating phenotypic, RNA sequencing, and metabolomic data, this study delineates the metabolic flux partitioning of flavonoids underlying floral pigmentation and antioxidant capacity across three S. vulgaris cultivars (blue, purple, and white). A core regulatory module of seven genes governs the biosynthesis of four flavonoid metabolites (kaempferol-3,7-diglucoside, kaempferol-3-sophorose-7-glucoside, kaempferol-3-rutinoside, and rutin) and two anthocyanidin metabolites (cyanidin-4-rutinoside and delphinidin-3-rutinoside), while shikimate acyltransferase gene ( SvHCT-4 ) acted as a pivotal node directing flux toward cyanidin-4-rutinoside and delphinidin-3-rutinoside accumulation. These flavonoids and anthocyanidins in S. vulgari s cultivars orchestrated stage-specific modulation of floral pigmentation and differentially enhanced the scavenging capacities of 2,2-Diphenyl-2-picrylhydrazyl radical (DPPH·) and hydroxyl radical (OH·). SvHCT-4 functions as a critical metabolic branch point governing metabolic flux partitioning from non-anthocyanin flavonoids to anthocyanin biosynthesis in the blue and purple cultivars of S. vulgaris , thereby enhancing floral pigmentation and antioxidant activity. The findings not only provided valuable insights into the intricate regulatory networks governing floral pigmentation and antioxidant capacity but also offered potential targets for future genetic engineering and breeding efforts aimed at enhancing these desirable traits in horticultural crops.

Ce résumé expose les affirmations des auteurs. BNTIC ne l’interprète pas comme une validation indépendante des résultats.