ABSTRACT Transcriptional regulation is the most important tool for enhancing flavonoid biosynthesis of plants. The grapevine VvMYBF1 gene has been shown to be involved in the regulation of flavonoid biosynthesis. However, very little is known about its roles in tolerance to abiotic stresses. In this study, VvMYBF1 gene was cloned from grapevine. Its overexpression significantly increased accumulation of flavonoids and salt and drought tolerance in transgenic Arabidopsis. Real-time quantitative PCR analysis showed that overexpression of VvMYBF1 up-regulated the genes related to flavonoid and proline biosynthesis, stress responses and ROS scavenging under salt and drought stresses. Further components analyses showed that the transgenic plants exhibited significant increases of total flavonoids and proline content, as well as significant reduction of H2O2 and malonaldehyde (MDA) content. Enzymatic analyses found that the significant increases of phenylalanine ammonia lyase (PAL), chalcone isomerase (CHI), flavonol synthase (FLS), dihydroflavonol reductase (DFR), pyrroline-5-carboxylate synthase (P5CS), superoxide dismutase (SOD) and peroxidase (POD) activities were observed in the transgenic plants. These findings imply functions of VvMYBF1 in accumulation of flavonoids and tolerance to salt and drought stresses. The VvMYBF1 gene has the potential to be used to increase the content of valuable flavonoids and improve tolerance to abiotic stresses in plants.

中文翻译：

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来自葡萄 (Vitis vinifera L.) 的 R2R3-MYB 转录因子 VvMYBF1 调节转基因拟南芥中黄酮类化合物的积累和非生物胁迫耐受性

摘要 转录调控是增强植物类黄酮生物合成的最重要工具。葡萄藤 VvMYBF1 基因已被证明参与类黄酮生物合成的调节。然而，人们对其在非生物胁迫耐受性方面的作用知之甚少。本研究从葡萄藤中克隆了 VvMYBF1 基因。其过表达显着增加了转基因拟南芥中黄酮类化合物的积累和耐盐性和耐旱性。实时定量 PCR 分析表明，VvMYBF1 的过表达上调了与黄酮类和脯氨酸生物合成、应激反应和盐和干旱胁迫下 ROS 清除相关的基因。进一步的成分分析表明，转基因植物的总黄酮和脯氨酸含量显着增加，以及显着降低 H2O2 和丙二醛 (MDA) 的含量。酶学分析发现苯丙氨酸解氨酶（PAL）、查耳酮异构酶（CHI）、黄酮醇合酶（FLS）、二氢黄酮醇还原酶（DFR）、吡咯啉-5-羧酸合酶（P5CS）、超氧化物歧化酶（SOD）和过氧化物酶显着增加在转基因植物中观察到 (POD) 活性。这些发现暗示了 VvMYBF1 在黄酮类化合物的积累和对盐和干旱胁迫的耐受性中的功能。VvMYBF1 基因有可能用于增加有价值的黄酮类化合物的含量并提高植物对非生物胁迫的耐受性。在转基因植物中观察到二氢黄酮醇还原酶（DFR）、吡咯啉-5-羧酸合酶（P5CS）、超氧化物歧化酶（SOD）和过氧化物酶（POD）活性。这些发现暗示了 VvMYBF1 在黄酮类化合物的积累和对盐和干旱胁迫的耐受性中的功能。VvMYBF1 基因有可能用于增加有价值的黄酮类化合物的含量并提高植物对非生物胁迫的耐受性。在转基因植物中观察到二氢黄酮醇还原酶（DFR）、吡咯啉-5-羧酸合酶（P5CS）、超氧化物歧化酶（SOD）和过氧化物酶（POD）活性。这些发现暗示了 VvMYBF1 在黄酮类化合物的积累和对盐和干旱胁迫的耐受性中的功能。VvMYBF1 基因有可能用于增加有价值的黄酮类化合物的含量并提高植物对非生物胁迫的耐受性。