豆科植物特有的SnRK1α4参与根瘤能量供给的机制研究

豆科植物结瘤是一个高度耗能的过程，其能量供给机制一直未有解析。我们前期研究首次发现了豆科植物特有的新型SnRK1α亚基α4；并发现在低氮胁迫后接种根瘤菌，α4参与抑制α1/α2蛋白含量和激酶活性；还发现上游激酶SnAK能磷酸化α4并使其滞留在细胞质中。本项目拟在此基础上，进一步深入分析α4的生物学功能； 探究激酶SnAK调控α4细胞质定位的生物学意义和分子机制；从结构、竞争结合、功能发挥多角度探究α4抑制α1/α2转录后水平的分子机理；通过对snrk1α4 CRISPR-cas9突变体、过表达及野生型材料做RNA- seq高通量测定，深入分析在根瘤器官发生过程中，能量代谢途径及信号通路的变化，挖掘关键差异基因，鉴定α4参与根瘤发育能量供给的下游靶标基因，明确α4调控根瘤能量供给的机理，丰富豆科植物共生固氮的理论。

Legume nodulation is a process of high energy consumption. The mechanism of its energy supply has not been resolved. For the first time, our previous study found the unique new SnRK1α4 subunit in legume, and α4’s involvement in the inhibition of α1/α2 protein content and its kinase activity. After inoculating rhizobium under low nitrogen stress, we also found that the upstream kinase SnAK phosphorylate α4 and retained it in the cytoplasm. Based on the findings, we propose to further analyze the biological function of α4, and explore the biological significance and molecular mechanism of kinase SnAK in regulating the cytoplasmic localization of α4. We will probe into the molecular mechanism of the post-transcription level inhibition of α1/α2 from the perspectives of structure, competitive binding and functional performance. We will further research the changes in energy metabolism pathway and signal pathway in the process of nodulation through RNA-seq high-throughput assay of snrk1α4 CRISPR-cas9 mutants, overexpression and wild-type materials. We will also investigate the key different genes, identify the downstream target genes of α4 participated in the nodule energy supply, clarify the energy supply mechanism of α4, and enrich the theory of symbiotic nitrogen fixation in legume.