MouseLight Neuron AA0143

A vast neural tracing effort by a team of Janelia scientists has upped the number of fully-traced neurons in the mouse brain by a factor of 10. Researchers can now download and browse the data in three dimensions. <br>Inside the mouse brain, individual neurons zigzag across hemispheres, embroider branching patterns and, researchers have now discovered, can even spool out spindly fibers up to 45 centimeters long.<br>Scientists can see and explore these wandering neural traces in 3-D in the most detailed map of mouse brain wiring yet created. The map reconstructs the shape and position of more than 300 of the 70 million neurons in the mouse brain. Previous efforts to trace the path of individual neurons had topped out in the dozens. <br>The selectively-labeled neurons were mapped in an iterative process with two-photon microscopy. The brain is sliced in 200-micron sections and a few dozen neurons are labeled at a time and imaged. Each brain imaged yields about 50 terabytes of data, each containing mapped neurons which can be browsed via the NeuronBrowser application. Researchers interested in the complete raw data set should contact Janelia to discuss obtaining it via hardware transfer.

贾内利亚（Janelia）科研团队开展的大规模神经示踪研究项目，将小鼠大脑中已完成全追踪的神经元数量提升了10倍。如今研究人员可下载并三维浏览该数据集。
在小鼠大脑内部，单个神经元会在左右脑半球间蜿蜒穿行，编织出繁复精巧的分支形态；研究人员此次还发现，它们甚至能延伸出长达45厘米的纤细纤维。
科学家可在这张迄今构建的最精细小鼠大脑连接图谱中，以三维形式查看并探索这些蜿蜒的神经轨迹。该图谱重建了小鼠大脑7000万个神经元中超过300个的形态与空间位置。此前的单神经元路径追踪研究，最多仅能完成数十个神经元的追踪。
研究团队采用双光子显微镜（two-photon microscopy）的迭代成像流程，对选择性标记的神经元进行定位成像。具体操作如下：将大脑切割为200微米厚的切片，每次标记并成像数十个神经元。每完成一个大脑样本的成像，可产生约50太字节的数据，其中包含已完成定位的神经元，研究人员可通过神经元浏览器（NeuronBrowser）应用程序进行浏览。如需获取完整原始数据集的研究人员，请联系贾内利亚（Janelia）协商通过硬件移交的方式获取。