MouseLight Neuron AA0531

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，将小鼠脑中完全示踪神经元的数量提升了10倍。研究人员如今可下载并以三维形式浏览该数据集。
在小鼠脑中，单个神经元会在大脑半球间蜿蜒穿行，编织出繁复的分支形态；研究人员此次还发现，神经元甚至可延伸出长达45厘米的纤细纤维。
科学家可在这张迄今最精细的小鼠大脑连接图谱中，以三维视角观察并探索这些蜿蜒的神经示踪结构。该图谱重构了小鼠脑中7000万神经元中超过300个的形态与位置，而此前的神经元单一路径示踪研究最多仅能完成数十个神经元的示踪。
此次研究采用双光子显微镜（two-photon microscopy）的迭代成像流程，对选择性标记的神经元进行映射。具体操作时，先将大脑切成200微米的薄片，每次标记并成像数十个神经元。每颗成像的大脑可产生约50太字节的数据，其中包含可通过神经元浏览器（NeuronBrowser）应用程序浏览的已映射神经元信息。若研究人员需获取完整原始数据集，可联系贾内利亚（Janelia）商讨通过硬件传输方式获取相关数据。