Expression of dynamin 2 mutant associated with Charcot-Marie-Tooth disease leads to aberrant actin dynamics and lamellipodia formation.
Expression of dynamin 2 mutant associated with Charcot-Marie-Tooth disease leads to aberrant actin dynamics and lamellipodia formation.
复制标题
与腓骨肌萎缩症相关的动力 2 突变体的表达导致肌动蛋白动力学异常和片状伪足形成。
DOI：
10.1016/j.neulet.2016.06.030
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发表时间：
2016
影响因子：
2.5
通讯作者：
K.
中科院分区：
文献类型：
--
作者：
Yamada;H.;Kobayashi;K.;Zhang;Y.;Takeda;T.;Takei;K.
Dynamin 2的特定突变与一种遗传性周围神经病变--夏科-玛丽-图斯病(CMT)有关。然而，这些突变对动力蛋白功能的影响，特别是与肌动蛋白细胞骨架的调节有关的影响仍不清楚。在这里，我们表达了一些与CMT相关的动力素突变体，以检测它们在U2OS细胞CMT发病机制中的作用。动力蛋白Cmt突变体555Δ3和K562E的异位表达使依赖于血清刺激的片状脂蛋白的形成减少了约50%；然而，只有K562E引起了肌动蛋白细胞骨架的异常。免疫荧光分析显示，K562E突变导致肌动蛋白束的径向排列消失，同时出现F-肌动蛋白簇。活细胞成像分析显示，在表达K562E的细胞中，长度缩短的F-肌动蛋白聚合物组装成固定的簇。K562E Dynamin突变体与F-肌动蛋白簇共定位，而与笼蛋白包被的PIT标记蛋白共定位减少。使用另一种细胞系HeLa和NG108-15细胞也得到了基本上相同的结果。本研究首次揭示了动力蛋白CMT突变与肌动蛋白动力学异常和片状脂血症之间的关系，这可能是CMT中雪旺细胞内吞和髓鞘形成缺陷的原因之一。
Specific mutations in dynamin 2 are linked to Charcot-Marie-Tooth disease (CMT), an inherited peripheral neuropathy. However, the effects of these mutations on dynamin function, particularly in relation to the regulation of the actin cytoskeleton remain unclear. Here, selected CMT-associated dynamin mutants were expressed to examine their role in the pathogenesis of CMT in U2OS cells. Ectopic expression of the dynamin CMT mutants 555Δ3 and K562E caused an approximately 50% decrease in serum stimulation-dependent lamellipodia formation; however, only K562E caused aberrations in the actin cytoskeleton. Immunofluorescence analysis showed that the K562E mutation resulted in the disappearance of radially aligned actin bundles and the simultaneous appearance of F-actin clusters. Live-cell imaging analyses showed F-actin polymers of decreased length assembled into immobile clusters in K562E-expressing cells. The K562E dynamin mutant colocalized with the F-actin clusters, whereas its colocalization with clathrin-coated pit marker proteins was decreased. Essentially the same results were obtained using another cell line, HeLa and NG108-15 cells. The present study is the first to show the association of dynamin CMT mutations with aberrant actin dynamics and lamellipodia, which may contribute to defective endocytosis and myelination in Schwann cells in CMT.