Anthocyanins are important pigments and nutrients in fruits. Red grape is popular because of the high anthocyanin content. Previous studies have identified VvMYBA1 and its homologs as key regulators of fruit color; however, other transcription factors (TFs) that contribute to fruit color remain poorly understood. The present study identified the R2R3-MYB TF VvMYB24, whose gene expression levels were significantly higher in red berries (L51, × L.) than in green berries (L20, × L.). Overexpression of in grape calli increased anthocyanin biosynthesis by upregulating the expression of specific structural genes ( and ). Furthermore, VvMYB24 interacted with VvMYBA1 to form a protein complex that additionally increased the expression of and . In addition, light-responsive TF VvHY5 could bind to the promoters to activate its transcription. Taken together, the results reveal a regulatory module, VvHY5-VvMYB24-VvMYBA1, that influences anthocyanin biosynthesis in grape.

中文翻译：

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VvHY5-VvMYB24-VvMYBA1转录因子级联调控葡萄花青素的生物合成


花青素是水果中重要的色素和营养物质。红葡萄因花青素含量高而广受欢迎。先前的研究已确定 VvMYBA1 及其同源物是水果颜色的关键调节因子；然而，人们对其他影响果实颜色的转录因子 (TF) 仍知之甚少。本研究鉴定出 R2R3-MYB TF VvMYB24，其基因表达水平在红色浆果 (L51, × L.) 中显着高于绿色浆果 (L20, × L.)。葡萄愈伤组织中的过度表达通过上调特定结构基因的表达来增加花青素的生物合成（和）。此外，VvMYB24 与 VvMYBA1 相互作用形成蛋白质复合物，进一步增加 和 的表达。此外，光响应性 TF VvHY5 可以与启动子结合以激活其转录。综上所述，结果揭示了一个调节模块 VvHY5-VvMYB24-VvMYBA1，它影响葡萄中花青素的生物合成。