GhACR1调控棉花耐盐的机理研究

The growth and productivity of cotton are adversely affected by high salinity with the salinization of land becoming more and more serious. It is important to identify salt-tolerant genes and exploring their regulation mechanisms for salt-tolerant cotton breeding through genetic engineering. In previous work, we successfully identified a gene named GhACR1 in cotton by VIGS-cDNA library screening. Under salt treatment, the expression level of GhACR1 was drastically enhanced in leaf and stem, whereas it was inhibited at first and then enhanced in root. Increased salt-tolerance was observed in GhACR1-silenced cotton seedlings. The results suggested important roles of GhACR1 in salt-tolerance regulation of cotton. In this research, we try to elucidate the mechanism GhACR1-mediated salt-tolerance of cotton by performing following experiments. The expression pattern and biochemical characterization of GhACR1 will be analyzed. GhACR1-silenced cotton seedlings will be obtained by virus-induced gene silencing technology. The physiological and biochemical mechanisms of GhACR1-mediated salt-tolerance of cotton will be revealed through physiological and biochemical measurements. Down-stream genes regulated by GhACR1 will be obtained by high-throughout transcriptome. A yeast two-hybrid screen will be performed to identify possible interacting partners of GhACR1. The results will reveal the molecular mechanism of GhACR1-mediated salt-tolerance of cotton. The execution of this research will be helpful to find new salt-tolerant pathway in cotton and provide gene resources for salt-tolerant cotton breeding through genetic engineering.

随着土壤盐渍化的日益加剧，高盐胁迫已成为棉花生产的主要限制因素之一。研究棉花盐胁迫响应基因的功能及其调控机制，对棉花耐盐遗传育种意义重大。我们前期研究获得的基因GhACR1表达在棉花幼苗的叶和茎中受盐诱导上调，在根中先下调后上调，GhACR1沉默的棉花幼苗耐盐性明显增强，提示GhACR1在棉花耐盐调控中发挥重要作用。本项目拟进一步阐明GhACR1调控棉花耐盐的机理，对GhACR1的表达模式和生化特性进行分析，采用病毒诱导的基因沉默技术获得GhACR1沉默的棉花幼苗，分析其耐盐生理指标和生化代谢谱，明确GhACR1调控棉花耐盐的生理生化机制，通过高通量测序寻找GhACR1下游调控基因，并结合酵母双杂交文库筛选GhACR1互作蛋白，构建GhACR1参与的代谢信号网络，解析GhACR1调控棉花耐盐的分子机制。研究结果将有助于揭示棉花新的耐盐途径，为培育棉花耐盐新品种提供基因储备和奠定基础。

高盐胁迫是限制棉花生产的主要因素之一。研究棉花盐胁迫响应基因的功能及其调控机制，对棉花耐盐遗传育种意义重大。本研究明确了盐胁迫响应基因GhACR1主要定位在细胞质、质膜和核膜中，在棉花根中的表达水平较其他组织高，其表达受盐、干旱、过氧化氢和ABA的调控；利用VIGS技术构建了pTRV-GhACR1重组表达载体，并转入棉花，成功获得GhACR1沉默的植株；正常生长条件下，GhACR1沉默植株与空载体对照的生长表型无明显差异，而在盐胁迫条件下，其具有明显的耐盐表型；盐胁迫条件下，与空载体对照组相比，GhACR1沉默植株中具有较高的抗氧化酶活性，较低的MDA和H2O2含量；盐胁迫条件下，沉默GhACR1明显改变了棉花幼苗的代谢谱和基因表达谱；筛选获得了GhACR1的互作蛋白。发表论文5篇，其中SCI收录1篇；培养研究生2名。