Regulation mechanisms of aquaporin in the brain and its functions in the brain edema

水通道蛋白（AQPs）是一种水通道蛋白，它增加了水通过质膜的渗透性，从而提供了快速流体运动的途径。在大脑中，AQP4大量表达，并高度集中在与毛细血管和瞳孔直接接触的星形胶质细胞膜上。AQP4被认为是在各种情况下大量水跨质膜转移的主要途径，并参与脑水肿的形成。然而，关于AQP4在大脑中表达调控的机制知之甚少。我们研究了与AQP4相互作用的分子，发现RIL是一个结合蛋白。实际上，通过体外结合实验、拉下实验、共免疫沉淀和免疫组织化学染色证实RIL与AQP4直接相互作用。我们正在准备RIL缺失小鼠的载体，以揭示RIL对AQP4的调控机制。RIL可能是一种新的脑水肿治疗方法的靶分子。

Aquaporins (AQPs) are water channel proteins, which increase water permeability via the plasma membrane and thus provide a route for rapid fluid movement. In the brain, AQP4 is abundantly expressed, and is highly concentrated in astrocyte membranes that are in direct contact with capillaries and pia. AQP4 is considered a major pathway for massive water shift across the plasma membrane under various conditions and is involved in brain edema formation. However, little is known concerning the mechanisms by which AQP4 expression is regulated in the brain. We investigated molecules, which interact with AQP4 and discovered RIL as a binding protein. Actually, it is confirmed that RIL directly interacted with AQP4 by in vitro binding assay, pull down assay, co-immunoprecipitation, and immunohistochemical staining. We are preparing a vector for a RIL null mouse, which reveals the regulation mechanisms of AQP4 by RIL. It is possible that RIL is a target molecule for a new therapeutic method of brain edema.