Overexpression of R2R3-MYB gene leads to accumulation of anthocyanin and enhanced resistance to chilling and oxidative stress
Overexpression of R2R3-MYB gene leads to accumulation of anthocyanin and enhanced resistance to chilling and oxidative stress
复制标题
R2R3-MYB基因的过度表达导致花青素的积累并增强对寒冷和氧化应激的抵抗力
DOI：
10.1007/s10535-013-0376-3
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发表时间：
2014-03-01
影响因子：
1.5
通讯作者：
Meng, Q. -W.
中科院分区：
文献类型：
--
作者：
Meng, X.;Yin, B.;Meng, Q. -W.
从番茄中分离到一个编码花青素相关的R2 R3-MYB转录因子的LeAN 2。低温和氧化胁迫诱导番茄LeAN 2基因的表达。将绿色荧光蛋白与LeAN 2融合，并在洋葱表皮细胞中瞬时表达。仅在细胞核中观察到绿色荧光。CaMV 35 S启动子控制下的LeAN 2在烟草中的过表达诱导了几个花青素生物合成基因的表达，转基因烟草中花青素含量显著高于野生型。与野生型烟草相比，转基因烟草通过保持较高的叶绿素含量、净光合速率和PS II的最大光化学效率来赋予对低温胁迫的耐受性。此外，转基因植株在低温胁迫下表现出较低的离子渗漏、较低的活性氧含量和较高的非酶抗氧化剂含量。他们还表现出增强的抗氧化胁迫诱导甲基紫精的基础上减少叶绿素含量的损失，较低的离子泄漏，增强PS II的最大光化学效率。这些结果表明，过量表达LeAN 2导致转基因烟草中花青素积累增加，增强了对低温和氧化胁迫的抗性。
LeAN2encoding an anthocyanin-associated R2R3-MYB transcription factor was isolated from tomato. The expression ofLeAN2in tomato was induced by low temperature and oxidative stress. Green fluorescent protein was fused toLeAN2and the complex was expressed transiently in onion epidermal cells. Green fluorescence was observed only in the nucleus. Overexpression ofLeAN2under the control of the CaMV35S promoter in tobacco induced expression of several anthocyanin biosynthetic genes and the content of anthocyanin was markedly higher in transgenic tobacco compared with wild type plants. Transgenic tobaccos conferred tolerance to chilling stress by maintaining a higher chlorophyll content, net photosynthetic rate, and maximal photochemical efficiency of PS II compared to the wild type plants. Furthermore, the transgenic plants showed lower ion leakage, a lower content of reactive oxygen species, and a higher content of non-enzymatic antioxidans under the chilling stress. They also showed an enhanced resistance to the oxidative stress induced by methyl viologen based on a decreased chlorophyll content loss, lower ion leakage, and an enhanced maximal photochemical efficiency of PS II. These results indicate that overexpression ofLeAN2resulted in an increased anthocyanin accumulation and enhanced resistance to the chilling and oxidative stresses in transgenic tobacco.