植物病害和营养元素氮的供应之间存在着密切的关联性，过量氮加重病害的发生，而低氮胁迫有助于提高水稻的抗病性。前期研究证明osa-miR169o是受病菌（Xanthomonas oryzae pv. oryzae）侵染和低氮胁迫共同调控的63个水稻miRNAs之一，不仅负调控水稻抗病性，而且促进水稻对氮的吸收利用，其中miR169的靶基因OsNF-YAs发挥了关键的作用，但OsNF-YAs参与水稻抗病性和氮吸收利用调控的内在作用机制却并不清楚。本项目拟通过ChIP-Seq技术，启动子活性分析，EMSA等挖掘、验证受转录因子OsNF-YAs直接调控的基因信息；再通过相关基因在抗病性、氮吸收利用上的功能分析来确定OsNF-YAs直接调控的抗病、氮吸收利用基因，从而明确OsNF-YAs在水稻miR169o调控的抗病性和氮吸收利用中的作用机制，为解析氮供应和水稻抗病性间的关联性提供研究基础和借鉴意义。

There is a closely relationship between the disease resistance and nitrogen fertilizer supplication. Our previous studies showed that nitrogen starvation stress promotes the disease resistance against Xanthomomans oryzae pv. oryzae (Xoo) which causes bacterial blight of rice, the important bacterial disease in rice. And further studies identified 63 overlapping miRNAs response to Xoo infection, limiting nitrogen stress, and combined stress in rice. Among these overlapping miRNAs, osa-miR169o not only negatively regulates the resistance against Xoo, but also positively promotes the nitrogen use efficieny and tolerance to nitrogen deficiency. Moreover, OsNF-YAs, targets of miR169, were key regulators in miR169o-modulated disease resistance and uptake of nitrogen. However, the underlying regulatory mechanism of OsNF-YAs in osa-miR169o-modulated plant resistance and nitrogen use efficiency is still unknown. Here, the item aims to characterize transcript factor OsNF-YAs-regulated disease resistance- and nitrogen ues efficiency-relative genes through ChIP-seq (Chromatin Immunoprecipitation, ChIP), promoter activity assay, EMSA (Electrophoretic Mobility Shift Assay, EMSA) and so on. Furthermore, the disease resistance and nitrogen use efficiency of OsNF-YAs-regulated genes will be measured in overexpression and CRISPR mutant transgenic plant, respectively. Finally, the underlying regulatory mechanism of osa-miR169o--OsNF-YAs on the disease resistance and nitrogen use efficiency in rice will be dissected. In general, the item will be helpful to understanding the intrinsic crosstalk between the nitrogen supplication and plant disease resistance in the long run.