Next Generation Sequencing Facilitates Small RNA Mediated Rice Resistance to Xoo. Oryza sativa Japonica Group

Purpose: The goal of this study is to identify small non-conding RNAs which are involved in rice resistance to Xoo. Methods: Rice leaves were inoculated with the Xoo strain PXO61 at the four-leaf to five-leaf stage by the leaf-clipping method. Control rice plants were inoculated with water (mock inoculation). And then, total RNA was extracted to be sequenced using Illumina GAIIx. Results: Using an optimized data analysis workflow to count the expression level of small ncRNA, we found several differentially expressed small ncRNA which may be participated in the interaction between rice and Xoo. Conclusions: Small ncRNA have be found to function in a variety of biological processes. Our study here has showed that several candidate miRNA or siRNA may play a significant role in rice immunity. Overall design: Plants were inoculated with the Xoo strain PXO61 at the four-leaf to five-leaf stage by the leaf-clipping method. Control rice plants were inoculated with water (mock inoculation). Samples were collected before inoculation (ck) and at 2, 4, and 24 hours after PXO61 or mock inoculation from Rb49 and MDJ8. Leaf fragments approximately 2 cm in length that were immediately next to the inoculation site were collected.

研究目的：本研究旨在鉴定参与水稻抗Xoo（水稻白叶枯病菌，Xanthomonas oryzae pv. oryzae）的小型非编码RNA（small non-coding RNA）。
试验方法：于四叶至五叶期的水稻植株上，采用剪叶法接种Xoo菌株PXO61；对照组水稻植株以无菌水进行模拟接种。随后提取总RNA，利用Illumina GAIIx测序平台进行测序。
研究结果：本研究采用优化后的数据分析流程统计小型非编码RNA的表达水平，筛选得到若干差异表达的小型非编码RNA，其可能参与水稻与Xoo的互作过程。
研究结论：小型非编码RNA已被证实参与多种生物学过程。本研究结果显示，若干候选miRNA（microRNA）或siRNA（small interfering RNA）可能在水稻免疫反应中发挥关键作用。
试验设计：采用剪叶法对四叶至五叶期的水稻植株接种Xoo菌株PXO61，对照组以无菌水进行模拟接种。分别于接种前（ck）以及PXO61接种或模拟接种后2、4、24小时，从Rb49和MDJ8两个水稻材料中采集样本；采集紧邻接种位点、长度约2 cm的叶片片段。