Compartmentalized Calcium Transients Trigger Dendrite Pruning in Drosophila Sensory Neurons
Compartmentalized Calcium Transients Trigger Dendrite Pruning in Drosophila Sensory Neurons
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DOI：
10.1126/science.1234879
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发表时间：
2013-06-21
期刊：
影响因子：
56.9
通讯作者：
Emoto, Kazuo
中科院分区：
文献类型：
--
作者：
Kanamori, Takahiro;Kanai, Makoto I.;Emoto, Kazuo
树突修剪对于塑造神经回路的最终连接至关重要，因为它可以去除不适当的投影，然而神经元如何有选择地去除不必要的树突分支仍然是难以捉摸的。在这里，我们展示了在特定树突分支中划分的钙瞬态作为时间和空间线索触发果蝇感觉神经元的修剪。钙瞬态在分支消除前3小时左右发生在局部树突中。在树突分支中，内在兴奋性局部增加，通过电压门控钙通道（VGCC）激活钙内流，而VGCC活性的阻断会损害修剪。进一步的遗传分析表明，钙活化蛋白酶钙蛋白酶在钙瞬态下游起作用。我们的研究结果揭示了区隔化的亚树突钙信号在树突分支的时空选择性消除中的重要性。
Dendrite pruning is critical for sculpting the final connectivity of neural circuits as it removes inappropriate projections, yet how neurons can selectively eliminate unnecessary dendritic branches remains elusive. Here, we show that calcium transients that are compartmentalized in specific dendritic branches act as temporal and spatial cues to trigger pruning in Drosophila sensory neurons. Calcium transients occurred in local dendrites at similar to 3 hours before branch elimination. In dendritic branches, intrinsic excitability increased locally to activate calcium influx via the voltage-gated calcium channels (VGCCs), and blockade of the VGCC activities impaired pruning. Further genetic analyses suggest that the calcium-activated protease calpain functions downstream of the calcium transients. Our findings reveal the importance of the compartmentalized subdendritic calcium signaling in spatiotemporally selective elimination of dendritic branches.