CRMP-2 Is Involved in Axon Growth Inhibition Induced by RGMa In Vitro and In Vivo
CRMP-2 Is Involved in Axon Growth Inhibition Induced by RGMa In Vitro and In Vivo
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CRMP-2 参与 RGMa 体外和体内诱导的轴突生长抑制
DOI：
10.1007/s12035-012-8385-3
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发表时间：
2013-06-01
影响因子：
5.1
通讯作者：
Qin, Xinyue
中科院分区：
文献类型：
--
作者：
Wang, Tianzhu;Wu, Xiaohui;Qin, Xinyue
排斥性导向分子-a（RGMa）与不同中枢神经系统（CNS）损伤中轴突生长抑制相关，但其信号通路尚不清楚。我们通过用RGMa蛋白、Rho激酶抑制剂（Y-27632）和GSK-3 β抑制剂培养新生大鼠原代皮层神经元，在体外检测了Rho激酶和GSK-3 β的共同下游靶标--红细胞蛋白反应介体蛋白-2（CRMP-2）的参与。我们通过在大鼠MCAO/再灌注模型中使用重组腺病毒（rAd-shRGMa）抑制RGMa表达来检查CRMP-2。RGMa在体外诱导神经突收缩和CRMP-2磷酸化，其被Rho激酶或GSK-3 β抑制剂逆转。大鼠MCAO/再灌注后，缺血皮质pCRMP-2蛋白表达明显增加，轴突受损严重，神经丝蛋白-200（NF-200）表达明显减少，神经功能缺损明显，下调RGMa后，上述改变均得到改善。我们得出结论，RGMa通过Rho激酶和GSK-3 β信号通路磷酸化CRMP-2抑制轴突生长。
Repulsive guidance molecule-a (RGMa) is associated with axon growth inhibition in different central nervous system (CNS) injuries, but its signaling pathways remain unclear. We examined the involvement of collapsin response mediator protein-2 (CRMP-2), a common downstream target of Rho-kinase and GSK-3 beta, in vitro by culturing neonatal rat primary cortical neurons with RGMa protein, Rho-kinase inhibitor (Y-27632), and GSK-3 beta inhibitor. We examined CRMP-2 in vivo by suppressing RGMa expression using recombinant adenovirus (rAd-shRGMa) in a rat MCAO/reperfusion model. RGMa induced neurite retraction and CRMP-2 phosphorylation in vitro, which were reversed by either Rho-kinase or GSK-3 beta inhibitors. After MCAO/reperfusion in rats, pCRMP-2 protein was greatly increased in the ischemic cortex, axons were damaged severely, Neurofilament-200 (NF-200) expression was significantly decreased, and neurological deficits were significant, which were all improved by down-regulating RGMa. We concluded RGMa inhibits axon growth by phosphorylating CRMP-2 via both Rho-kinase and GSK-3 beta signaling pathways.