LINGO-1 Receptor Promotes Neuronal Apoptosis by Inhibiting WNK3 Kinase Activity
LINGO-1 Receptor Promotes Neuronal Apoptosis by Inhibiting WNK3 Kinase Activity
复制标题
LINGO-1 受体通过抑制 WNK3 激酶活性促进神经元凋亡
DOI：
10.1074/jbc.m112.447771
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发表时间：
2013-04-26
影响因子：
4.8
通讯作者：
He, Cheng
中科院分区：
文献类型：
--
作者：
Zhang, Zhaohuan;Xu, Xiaohui;He, Cheng
LINGO-1是Nogo受体1.p75（NTR）、LINGO-1和Nogo受体1.TAJ（TNFRSF 19/TROY）、LINGO-1信号传导复合物的功能组分。最近已经表明，LINGO-1拮抗剂显著改善神经损伤后的神经元存活。然而，LINGO-1信号传导影响细胞凋亡易感性的机制仍然未知。为了更好地理解LINGO-1如何调节这些信号通路，我们使用了一个建立的血清剥夺（SD）模型来诱导神经元凋亡。我们证明，治疗无论是与含有LINGO-1的细胞内结构域的构建体或与Nogo 66，LINGO-1受体复合物激动剂，导致在SD下的原代培养的皮层神经元的凋亡率提高。使用shRNA降低丝氨酸/苏氨酸激酶WNK 3的表达水平或抑制其激酶活性对血清剥夺神经元的存活具有类似的影响。与这些观察结果一致，我们发现LINGO-1和WNK 3在培养的皮层神经元和脑组织中共定位和共沉淀。值得注意的是，Nogo 66处理增强了这种共缔合。WNK 3与LINGO-1细胞内结构域的结合导致WNK 3激酶活性降低，Nogo 66刺激也是如此。此外，体外和体内证据表明，内源性WNK 3以激酶依赖性方式抑制SD诱导的神经元凋亡，因为WNK 3 RNAi构建体或WNK 3的激酶死亡N末端片段的表达导致凋亡增加。总之，我们的结果表明LINGO-1可能通过抑制WNK 3激酶活性来增强神经元凋亡。
LINGO-1 is a functional component of the Nogo receptor 1.p75(NTR).LINGO-1 and Nogo receptor 1.TAJ (TNFRSF19/TROY).LINGO-1 signaling complexes. It has recently been shown that LINGO-1 antagonists significantly improve neuronal survival after neural injury. However, the mechanism by which LINGO-1 signaling influences susceptibility to apoptosis remains unknown. In an effort to better understand how LINGO-1 regulates these signaling pathways, we used an established model of serum deprivation (SD) to induce neuronal apoptosis. We demonstrate that treatment either with a construct containing the intracellular domain of LINGO-1 or with Nogo66, a LINGO-1 receptor complex agonist, resulted in an enhanced rate of apoptosis in primary cultured cortical neurons under SD. Reducing the expression levels of the serine/threonine kinase WNK3 using shRNA or inhibiting its kinase activity had similar effects on the survival of serum-deprived neurons. Consistent with these observations, we found that LINGO-1 and WNK3 co-localized and co-precipitated in cultured cortical neurons and brain tissue. Significantly, this co-association was enhanced by Nogo66 treatment. Binding of WNK3 to the intracellular domain of LINGO-1 led to a reduction in WNK3 kinase activity, as did Nogo66 stimulation. Moreover, in vitro and in vivo evidence indicates that endogenous WNK3 suppresses SD-induced neuronal apoptosis in a kinase-dependent manner, as the expression of either a WNK3 RNAi construct or a kinase-dead N-terminal fragment of WNK3 led to increased apoptosis. Taken together, our results show that LINGO-1 potentiates neuronal apoptosis, likely by inhibiting WNK3 kinase activity.