miR1432及其靶标基因参与调控小麦与条锈菌互作的机理研究

Wheat stripe rust, caused by Puccinia striiformis f. sp. tritici (Pst), is among the most destructive wheat diseases in the world. Wheat yield can be greatly reduced or even completely destroyed at an epidemic level. The research of miRNAs regulating net in host-pathogens interaction add further insights on the mechanism of interaction between wheat and Pst. Thus, wheat-Pst interaction sRNA library was constructed through the separation of small-sized RNA and high-throughput sequencing. Within this library, we found the expression of wheat miR1432 was obviously up-regulated in compatible interaction, and down-regulated in incompatible interaction. In this research, we have predicted miR1432 could bind a target gene TaCML. To find the key time points of miR1432 regulate TaCML, we will use qRT-PCR to analyze expressions of miR1432 and TaCML in wheat-Pst interaction at different time after ininoculated. Then, we plan to further study the exact role of miR1432 and TaCM in the interaction between wheat and Pst, identify its host targets and analyze the roles of the target genes via co-transformation, gene silencing, and so on. The information obtained in this study will reveal the mechanism of sRNAs involving in the induced defense response. Moreover, it will provide theoretical basis for developing new strategies for durable control of wheat stripe rust.

小麦条锈病是一类世界范围内的小麦真菌病害，严重威胁着全球小麦生产。而通过研究miRNAs在寄主与病原菌互作过程中的调控网络，为抗锈研究提供了新的思路。为此，课题组首先完成小麦与小麦条锈菌互作过程的miRNAs高通量测序，其中发现小麦miR1432在与条锈菌的感病组合中显著地上调表达，而在抗病组合中显著地下调表达。本研究在前期研究基础上，通过生物信息学预测发现了miR1432的一个小麦抗逆相关靶标基因TaCML。通过对miR1432及靶标TaCML在小麦与条锈菌互作时对应的表达分析，明确其调节的关键时间点。利用共转化、基因沉默等技术分别对miR1432及靶标基因TaCML进行功能解析。研究结果为揭示sRNAs调控小麦抗条锈菌的分子机理奠定基础，进而为条锈病防治新策略的制定提供理论。

小麦条锈病是一类世界范围内的小麦真菌病害，严重威胁着全球小麦生产。而通过研究miRNAs在寄主与病原菌互作过程中的调控网络，为抗锈研究提供了新的思路。为此，课题组首先完成小麦与小麦条锈菌互作过程的miRNAs高通量测序，其中发现小麦miR1432在与条锈菌的感病组合中显著地上调表达，而在抗病组合中显著地下调表达，进一步通过定量分析48 h为调控关键时间点。通过生物信息学预测发现了miR1432的一个小麦抗逆相关靶标基因TaCML，利用降解组分析miR1432在12位碱基上切割TaCML。利用共转化实验，发现miR1432能够在植物体内切割TaCML。进一步利用VIGS技术沉默TaCML，发现小麦对非亲和条锈菌CYR23号小种抗性降低，出现产孢现象，表明TaCML负调控小麦的抗性。对互作过程中的小麦ROS检测发现，沉默TaCMl的植株ROS显著降低。综上表明miR1432负调控参与ROS通路的TaCML，影响小麦的抗锈性。研究结果为揭示sRNAs调控小麦抗条锈菌的分子机理奠定基础，进而为条锈病防治新策略的制定提供理论。