Luo Xiuqin, An Feifei, Xue Jingjing, Zhu Wenli, Wei Zhuowen, Ou Wenjun, Li Kaimian, Chen Songbi, Cai Jie
Tropical Crops Genetic Resources Institute, Chinese Academy of Tropical Agricultural Sciences/Key Laboratory of Ministry of Agriculture and Rural Affairs for Germplasm Resources Conservation and Utilization of Cassava, Haikou, China.
Front Plant Sci. 2023 Jun 9;14:1181257. doi: 10.3389/fpls.2023.1181257. eCollection 2023.
Cassava ( Crantz) leaves are often used as vegetables in Africa. Anthocyanins possess antioxidant, anti-inflammatory, anti-cancer, and other biological activities. They are poor in green leaves but rich in the purple leaves of cassava. The mechanism of anthocyanin's accumulation in cassava is poorly understood. In this study, two cassava varieties, SC9 with green leaves and Ziyehuangxin with purple leaves (PL), were selected to perform an integrative analysis using metabolomics and transcriptomics. The metabolomic analysis indicated that the most significantly differential metabolites (SDMs) belong to anthocyanins and are highly accumulated in PL. The transcriptomic analysis revealed that differentially expressed genes (DEGs) are enriched in secondary metabolites biosynthesis. The analysis of the combination of metabolomics and transcriptomics showed that metabolite changes are associated with the gene expressions in the anthocyanin biosynthesis pathway. In addition, some transcription factors (TFs) may be involved in anthocyanin biosynthesis. To further investigate the correlation between anthocyanin accumulation and color formation in cassava leaves, the virus-induced gene silencing (VIGS) system was used. VIGS- silenced plant showed the altered phenotypes of cassava leaves, partially from green to purple color, resulting in a significant increase of the total anthocyanin content and reduction in the expression of . These results provide a theoretical basis for breeding cassava varieties with anthocyanin-rich leaves.
木薯（Crantz）叶在非洲常被用作蔬菜。花青素具有抗氧化、抗炎、抗癌等生物活性。它们在木薯绿叶中含量较低，但在紫叶中含量丰富。木薯中花青素积累的机制尚不清楚。在本研究中，选择了两个木薯品种，绿叶的SC9和紫叶的紫叶黄心（PL），使用代谢组学和转录组学进行综合分析。代谢组学分析表明，最显著差异代谢物（SDMs）属于花青素，且在PL中高度积累。转录组学分析显示，差异表达基因（DEGs）在次生代谢物生物合成中富集。代谢组学和转录组学结合分析表明，代谢物变化与花青素生物合成途径中的基因表达相关。此外，一些转录因子（TFs）可能参与花青素生物合成。为了进一步研究木薯叶中花青素积累与颜色形成之间的相关性，使用了病毒诱导基因沉默（VIGS）系统。VIGS沉默的植株表现出木薯叶表型的改变，部分从绿色变为紫色，导致总花青素含量显著增加，且 的表达降低。这些结果为培育富含花青素叶片的木薯品种提供了理论依据。
