Ministry of Agriculture of R.P. China Key Laboratory of Monitoring and Management of Crop Pathogens and Insect Pests, Nanjing Agricultural University, Nanjing, 210095, China.
Gene. 2011 Oct 10;485(2):146-52. doi: 10.1016/j.gene.2011.06.026. Epub 2011 Jun 30.
Abiotic stress seriously affects crop growth and productivity. To better understand the mechanisms plant uses to cope with drought, cold and salt stress, it is necessary to isolate and characterize important regulators response to these stresses. In this study, we cloned a MYB gene from wheat (Triticum aestivum L.) and designated it as TaMYB3R1 based on its conserved three repeats in MYB domain. The sequence of TaMYB3R1 protein shares high identity to other plant MYB3R proteins. Subcellular localization experiment in onion epidermal cells proved that TaMYB3R1 localized in the nucleus. Trans-activation essays in yeast cells confirmed that TaMYB3R1 was a transcriptional activator, and only C-terminal region was able to activate the expression of β-galactosidase. DNA-binding test showed the MSA cis element-binding activity of TaMYB3R1. After exogenous application of phytohormone ABA, the expression of TaMYB3R1 was induced, and its transcripts accumulated up to 24h; this is also the case for MeJA treatment, but after it peaked at 4h, it decreased to low levels. However, either SA or ET had no obvious effect on the expression of TaMYB3R1. Furthermore, the TaMYB3R1 was initially expressed at low levels and was gradually induced following treatment with salt, and continued to increase up to 72 h. This was similar for the cold treatment. In contrast, the peak appeared at 6h of the PEG treatment, and then gradually decreased to low levels. Our results suggest that TaMYB3R1 is potentially involved in wheat response to drought, salt and cold stress.
非生物胁迫严重影响作物生长和生产力。为了更好地理解植物应对干旱、寒冷和盐胁迫的机制，有必要分离和鉴定应对这些胁迫的重要调控因子。在本研究中，我们从小麦（Triticum aestivum L.）中克隆了一个 MYB 基因，并根据其 MYB 结构域中的三个重复序列将其命名为 TaMYB3R1。TaMYB3R1 蛋白的序列与其他植物 MYB3R 蛋白具有高度的同源性。洋葱表皮细胞的亚细胞定位实验证明 TaMYB3R1 定位于细胞核。酵母细胞的转录激活实验证实 TaMYB3R1 是一个转录激活子，只有 C 端区域能够激活 β-半乳糖苷酶的表达。DNA 结合试验表明 TaMYB3R1 具有 MSA 顺式元件结合活性。外源施加植物激素 ABA 后，TaMYB3R1 的表达被诱导，其转录本在 24 小时内积累；MeJA 处理也是如此，但在 4 小时达到峰值后，其表达水平下降到较低水平。然而，SA 或 ET 对 TaMYB3R1 的表达没有明显影响。此外，TaMYB3R1 的初始表达水平较低，经盐处理后逐渐诱导，并持续增加至 72 小时。冷处理也是如此。相比之下，PEG 处理的峰值出现在 6 小时，然后逐渐下降到低水平。我们的结果表明，TaMYB3R1 可能参与小麦对干旱、盐和冷胁迫的响应。
