Membrane biogenesis in the sprouting neuron. I. Selective transfer of newly synthesized phospholipid into the growing neurite.
Membrane biogenesis in the sprouting neuron. I. Selective transfer of newly synthesized phospholipid into the growing neurite.
复制标题
萌芽神经元中的膜生物发生。 I.新合成的磷脂选择性转移到生长的神经突中。
DOI：
10.1083/jcb.97.4.1038
复制
发表时间：
1983-10
期刊：
影响因子：
--
通讯作者：
Johnson MP
中科院分区：
文献类型：
--
作者：
Pfenninger KH;Johnson MP
我们的目标是阐明新合成的磷脂进入生长的神经突的途径。这是通过磷脂前体[3H]甘油的脉冲追踪研究实现的，使用大鼠颈上神经节的发芽外植体培养物作为实验系统。在前体脉冲和不同的追踪周期之后，我们通过显微外科手术分离核周和神经突并提取它们的磷脂。核周磷脂提取物的比放射性先急剧上升，然后迅速下降。相反，仅在大约 60 分钟的滞后期后才观察到磷脂的神经炎特异性放射性增加。可以证明新合成的磷脂从核周到神经突的几乎定量的转移。核周特异性放射性的下降和其神经炎对应物（即近远端转移）的增加都可以用微管药物秋水仙碱和代谢解偶联剂 2,4-二硝基苯酚来阻断。这些观察表明，新合成的磷脂优先从核周（主要或唯一的合成位点）输出到生长的神经突中，最有可能是通过形成元件的快速轴浆运输。
Our goal was to elucidate the pathway of newly synthesized phospholipid into the growing neurite. This was accomplished in pulse-chase studies with the phospholipid precursor [3H]glycerol, using sprouting explant cultures of rat superior cervical ganglion as an experimental system. After the pulse with the precursor and various chase periods, we separated perikarya and neurites microsurgically and extracted their phospholipids. The phospholipid extract from the perikarya exhibited a steep rise followed by a rapid decline in specific radioactivity. In contrast, an increase in neuritic specific radioactivity of phospholipid was observed only after a lag period of approximately 60 min. Nearly quantitative transfer of newly synthesized phospholipid from the perikarya into the neurites could be demonstrated. Both the decline in perikaryal specific radioactivity and the increase in its neuritic counterpart, i.e., the proximodistal transfer, could be blocked with the microtubule drug colchicine and the metabolic uncoupler, 2,4-dinitrophenol. These observations indicate preferential export of newly synthesized phospholipid from the perikaryon (the major or exclusive site of synthesis) into the growing neurites, most likely by rapid axoplasmic transport of formed elements.