Suppression of KIF2 in PC12 cells alters the distribution of a growth cone nonsynaptic membrane receptor and inhibits neurite extension
Suppression of KIF2 in PC12 cells alters the distribution of a growth cone nonsynaptic membrane receptor and inhibits neurite extension
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DOI：
10.1083/jcb.138.3.657
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发表时间：
1997-08-11
影响因子：
7.8
通讯作者：
Caceres, A
中科院分区：
文献类型：
--
作者：
Morfini, G;Quiroga, S;Caceres, A
在本研究中，我们提供了关于KIF 2的细胞功能的证据，KIF 2是一种具有独特结构的驱动蛋白样超家族成员，其马达结构域位于分子的中心（Noda Y.，Y. Sato-Yoshitake，S.近藤Nangaku和N. Hirokawa，1995年。细胞生物学杂志，129：157-167。）。使用亚细胞分离技术，isopicnic蔗糖密度离心微粒体组分从发展中的大鼠大脑皮层，和免疫隔离与KIF 2抗体，我们现在已经确定了一种类型的nonsynaptic囊泡，与KIF 2。这种类型的细胞器缺乏突触囊泡标记物（突触蛋白、突触泡蛋白）、淀粉样前体蛋白、GAP-43或N-钙粘蛋白。另一方面，它含有β（gc），这是IGF-1受体β亚基的一种新变体，在生长锥膜中高度富集。β（gc）和KIF 2在PC 12细胞中均被NGF上调，并高度集中在发育神经元的生长锥中。我们还分析了反义寡核苷酸治疗抑制KIF 2对神经细胞形态发生和突触和非突触囊泡标记物分布的影响。KIF 2抑制导致细胞体内β（gc）的急剧积累，并使其从生长锥中完全消失;在KIF 2抑制的神经元中检测到突触蛋白、突触素、GAP-43或淀粉样前体蛋白的分布没有改变。相反，它们都在神经末梢高度富集。KIF 2抑制也产生了显着抑制神经突生长;这种现象发生后，β（GC）已经从生长锥消失。总的来说，我们的研究结果表明KIF 2在神经突延伸中的重要作用，这种现象可能与一种非突触囊泡的顺行运输有关，该囊泡包含IGF-1的生长锥膜受体，IGF-1是一种与神经细胞发育有关的生长因子。
In the present study, we present evidence about the cellular functions of KIF2, a kinesin-like superfamily member having a unique structure in that its motor domain is localized at the center of the molecule (Noda Y., Y. Sato-Yoshitake, S. Kondo, M. Nangaku, and N. Hirokawa, 1995. J. Cell Biol, 129:157-167.). Using subcellular fractionation techniques, isopicnic sucrose density centrifugation of microsomal fractions from developing rat cerebral cortex, and immunoisolation with KIF2 antibodies, we have now identified a type of nonsynaptic vesicle that associates with KIF2. This type of organelle lacks synaptic vesicle markers (synapsin, synaptophysin), amyloid precursor protein, GAP-43, or N-cadherin, On the other hand, it contains beta(gc), which is a novel variant of the beta subunit of the IGF-1 receptor, which is highly enriched in growth cone membranes. Both beta(gc) and KIF2 are upregulated by NGF in PC12 cells and highly concentrated in growth cones of developing neurons. We have also analyzed the consequences of KIF2 suppression by antisense oligonucleotide treatment on nerve cell morphogenesis and the distribution of synaptic and nonsynaptic vesicle markers. KIF2 suppression results in a dramatic accumulation of beta(gc) within the cell body and in its complete disappearance from growth cones; no alterations in the distribution of synapsin, synaptophysin, GAP-43, or amyloid percursor protein are detected in KIF2-suppressed neurons. Instead, all of them remained highly enriched at nerve terminals. KIF2 suppression also produces a dramatic inhibition of neurite outgrowth; this phenomenon occurs after beta(gc) has disappeared from growth cones. Taken collectively, our results suggest an important role for KIF2 in neurite extension, a phenomenon that may be related with the anterograde transport of a type of nonsynaptic vesicle that contains as one of its components a growth cone membrane receptor for IGF-1, a growth factor implicated in nerve cell development.