The role of neuronal identity in synaptic competition
The role of neuronal identity in synaptic competition
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DOI：
10.1038/nature01836
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发表时间：
2003-07-24
期刊：
影响因子：
64.8
通讯作者：
Lichtman, JW
中科院分区：
文献类型：
--
作者：
Kasthuri, N;Lichtman, JW
在哺乳动物肌肉发育过程中，几个运动神经元的轴突分支共同支配同一肌肉纤维。它们之间的竞争导致一个的加强和其余的退出（1，2）。目前尚不清楚为什么一个特定的轴突分支存活下来，或者为什么一些竞争比其他竞争解决得更快（3）。在这里，我们表明，轴突分支的命运是严格相关的轴突与它们竞争的身份。当两个神经元共同支配多个靶细胞时，在每次竞争中失去的轴突分支属于同一个神经元，并且处于几乎相同的撤回阶段。一个神经元的轴突同时参与多组竞争。每一组都以不同的速度进行，并根据竞争对手的身份走向共同的结果。这些局部竞争的竞争活力取决于全局分布的资源：当面对具有较小分支的神经元时，具有较大分支的神经元处于竞争劣势。一个附带的文件测试的想法，释放的神经递质的量是这个全球资源（4）。
In developing mammalian muscle, axon branches of several motor neurons co-innervate the same muscle fibre. Competition among them results in the strengthening of one and the withdrawal of the rest(1,2). It is not known why one particular axon branch survives or why some competitions resolve sooner than others(3). Here we show that the fate of axonal branches is strictly related to the identity of the axons with which they compete. When two neurons co-innervate multiple target cells, the losing axon branches in each contest belong to the same neuron and are at nearly the same stage of withdrawal. The axonal arbor of one neuron engages in multiple sets of competitions simultaneously. Each set proceeds at a different rate and heads towards a common outcome based on the identity of the competitor. Competitive vigour at each of these sets of local competitions depends on a globally distributed resource: neurons with larger arborizations are at a competitive disadvantage when confronting neurons with smaller arborizations. An accompanying paper tests the idea that the amount of neurotransmitter released is this global resource(4).