AMP-激活蛋白激酶（AMPK）是胞内一种重要的感知能量状态的感受因子。在能量缺乏时，AMP（相对于ATP）的水平增加，AMP结合到AMPK后还需LKB1磷酸化AMPK才能完全激活AMPK，使得LKB1-AMPK信号通路是细胞感知能量压力最重要的信号通路。我们在研究Axin代谢功能时发现，Axin可与LKB1和AMPK相互作用形成复合体，用siRNA敲低Axin表达，会抑制能量饥饿引起的AMPK激活和LKB1转移。LKB1 第428位丝氨酸磷酸化是其核质转移所必需。我们发现Axin促进LKB1 Ser428磷酸化。目前关于LKB1转运的调节机制还不明确。我们计划通过免疫荧光，免疫共沉淀，核质分离，流式细胞计数，体外重组等实验，阐明细胞在能量压力下，Axin调节LKB1转运的机制，及其生物学意义。这个工作将有助于深入理解AMPK在能量压力下如何激活。

The AMP-activated protein kinase (AMPK) is the principal sensor of energy states. Under nutritional deprivation, hypoxia or heightened exercise, AMP levels (relative to ATP) are increased.In addition to AMP binding, AMPK requires the presence of the liver kinase B1 (LKB1) for activation. Therefore, the LKB1-AMPK signalling axis is the most important system for cells to respond to metabolic stresses. When we explored physilogical function of Axin, we found that Axin could enhance the interaction of LKB1 and AMPK。Knocking down Axin by siRNA could suppress AMPK activation and LKB1 translocation undter nutrient-poor conditions. LKB1 Ser428 phosphorylation is required for nucleocytoplasmic transport of LKB1. We dicovered that Axin can increase Ser428 phosphorylation of LKB1. However, the mechanism for the regulation of LKB1 translocation remains unclear. We hereby propose to explore the mechanism and the bilogical significance of the regulation of LKB1 translation by Axin by using immunofluorescence assay, subcellular fractionation, flow cytometry, and in vitro reconstitution assay. This work will make important advancement for the understanding of how AMPK is activated by energy stress.