During development, neurons navigate a tangled thicket of thousands of axons and dendrites to synapse with just a few specific targets. This phenomenon termed wiring specificity, is critical to the assembly of neural circuits and the way neurons manage this feat is only now becoming clear. Recent studies in the mouse retina are shedding new insight into this process. They show that specific wiring arises through a series of stages that include: directed axonal and dendritic growth, the formation of neuropil layers, positioning of such layers, and matching of co-laminar synaptic partners. Each stage appears to be directed by a distinct family of recognition molecules, suggesting that the combinatorial expression of such family members might act as a blueprint for retinal connectivity. By reviewing the evidence in support of each stage, and by considering their underlying molecular mechanisms, we attempt to synthesize these results into a wiring model which generates testable predictions for future studies. Finally, we conclude by highlighting new optical methods that could be used to address such predictions and gain further insight into this fundamental process.

中文翻译：

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研究视网膜神经回路组装的新光学工具。

在发育过程中，神经元在由数以千计的轴突和树突组成的错综复杂的灌木丛中穿行，仅与几个特定目标形成突触。这种称为布线特异性的现象对于神经回路的组装至关重要，而神经元管理这一壮举的方式现在才变得清晰。最近对小鼠视网膜的研究正在为这一过程提供新的见解。他们表明，特定的布线是通过一系列阶段产生的，包括：定向轴突和树突生长、神经纤维层的形成、这些层的定位以及共层突触伙伴的匹配。每个阶段似乎都由一个不同的识别分子家族指导，这表明这些家族成员的组合表达可能充当视网膜连接的蓝图。通过审查支持每个阶段的证据，并通过考虑它们的潜在分子机制，我们尝试将这些结果综合成一个接线模型，为未来的研究生成可测试的预测。最后，我们强调了可用于解决此类预测并进一步了解这一基本过程的新光学方法。