α-Synuclein Expression in Rat Substantia Nigra Suppresses Phospholipase D2 Toxicity and Nigral Neurodegeneration
α-Synuclein Expression in Rat Substantia Nigra Suppresses Phospholipase D2 Toxicity and Nigral Neurodegeneration
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DOI：
10.1038/mt.2010.137
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发表时间：
2010-10-01
影响因子：
12.4
通讯作者：
Muzyczka, Nicholas
中科院分区：
文献类型：
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作者：
Gorbatyuk, Oleg S.;Li, Shoudong;Muzyczka, Nicholas
我们提出的遗传证据表明，α-突触核蛋白 (α-syn) 的体内作用是抑制磷脂酶 D2 (PLD2)，这种酶被认为参与囊泡运输、膜信号传导以及胞吐作用和胞吐作用。 PLD2 在大鼠黑质致密部 (SNc) 中的过度表达导致多巴胺 (DA) 神经元的严重神经变性、纹状体 DA 的丧失以及相关的同侧安非他明诱导的旋转不对称。人野生型 α-syn 的共表达可抑制 PLD2 神经变性、DA 丢失和安非他明诱导的旋转不对称。然而，在体外抑制PLD2有缺陷的α-syn突变体也未能在体内抑制PLD毒性。此外，通过 siRNA 敲低 PLD2 或过度表达 α-syn，SNc 中 PLD2 活性的降低都会产生不寻常的对侧安非他明诱导的旋转不对称性，与 PLD2 过度表达所观察到的情况相反，表明 PLD2 和 α-syn 均参与 DA 释放或再摄取。最后，α-syn 与纹状体组织提取物中的 PLD2 进行免疫共沉淀。综上所述，我们的数据证明 α-syn 是体内 PLD2 的抑制剂，并证实了早期关于 α-syn 体外抑制 PLD2 的报道。我们的数据还表明，可以使用病毒介导的基因转移来研究体内基因相互作用。
We present genetic evidence that an in vivo role of alpha-synuclein (alpha-syn) is to inhibit phospholipase D2 (PLD2), an enzyme that is believed to participate in vesicle trafficking, membrane signaling, and both endo- and exocytosis. Overexpression of PLD2 in rat substantia nigra pars compacta (SNc) caused severe neurodegeneration of dopamine (DA) neurons, loss of striatal DA, and an associated ipsilateral amphetamine-induced rotational asymmetry. Coexpression of human wild type alpha-syn suppressed PLD2 neurodegeneration, DA loss, and amphetamine-induced rotational asymmetry. However, an alpha-syn mutant defective for inhibition of PLD2 in vitro also failed to inhibit PLD toxicity in vivo. Further, reduction of PLD2 activity in SNc, either by siRNA knockdown of PLD2 or overexpression of alpha-syn, both produced an unusual contralateral amphetamine-induced rotational asymmetry, opposite to that seen with overexpression of PLD2, suggesting that PLD2 and alpha-syn were both involved in DA release or reuptake. Finally, alpha-syn coimmunoprecipitated with PLD2 from extracts prepared from striatal tissues. Taken together, our data demonstrate that alpha-syn is an inhibitor of PLD2 in vivo, and confirm earlier reports that alpha-syn inhibits PLD2 in vitro. Our data also demonstrate that it is possible to use viral-mediated gene transfer to study gene interactions in vivo.