PDF(Pubmed)
Abstract：
Intrinsically photosensitive retinal ganglion cells (ipRGCs) are specialized retinal output neurons that mediate behavioral, neuroendocrine, and developmental responses to environmental light. There are diverse molecular strategies for marking ipRGCs, especially in mice, making them among the best characterized retinal ganglion cells (RGCs). With the development of more sensitive reporters, new subtypes of ipRGCs have emerged. We therefore tested high-sensitivity reporter systems to see whether we could reveal yet more. Substantial confusion remains about which of the available methods, if any, label all and only ipRGCs. Here, we compared many different methods for labeling of ipRGCs, including anti-melanopsin immunofluorescence, Opn4-GFP BAC transgenic mice, and Opn4cre mice crossed with three different Cre-specific reporters (Z/EG, Ai9, and Ai14) or injected with Cre-dependent (DIO) AAV2. We show that Opn4cre mice, when crossed with sensitive Cre-reporter mice, label numerous ganglion cell types that lack intrinsic photosensitivity. Though other methods label ipRGCs specifically, they do not label the entire population of ipRGCs. We conclude that no existing method labels all and only ipRGCs. We assess the appropriateness of each reporter for particular applications and integrate findings across reporters to estimate that the overall abundance of ipRGCs among mouse RGCs may approach 11%.
摘要：
固有光敏视网膜神经节细胞（ipRGC）是专门的视网膜输出神经元，介导行为，神经内分泌,和对环境光的发育反应。有不同的分子策略来标记ipRGC，尤其是在老鼠身上，使它们成为特征最好的视网膜神经节细胞（RGCs）之一。随着更敏感记者的发展，新的ipRGC亚型已经出现。因此，我们测试了高灵敏度的记者系统，看看我们是否可以揭示更多。关于哪种可用的方法仍然存在很大的困惑，如果有的话,标记所有且仅有ipRGC。这里,我们比较了许多不同的标记ipRGC的方法，包括抗黑素免疫荧光，Opn4-GFPBAC转基因小鼠,和Opn4cre小鼠与三种不同的Cre特异性报道分子杂交(Z/EG，Ai9和Ai14)或注射Cre依赖性(DIO)AAV2。我们展示了Opn4cre小鼠，当与敏感的Cre报告小鼠杂交时，标记许多缺乏内在光敏性的神经节细胞类型。尽管其他方法特别标记了ipRGC，它们不会标记整个ipRGC群体。我们得出的结论是，没有现有的方法标记所有且仅有ipRGC。我们评估每个报告子对于特定应用的适当性，并整合报告子的发现，以估计小鼠RGC中ipRGC的总体丰度可能接近11％。
