MouseLight Neuron AA1576

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. 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. 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. 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 at https://ml-neuronbrowser.janelia.org/. Researchers interested in the complete raw data set should contact Janelia to discuss obtaining it via hardware transfer.贾努利亚（Janelia）科研团队开展的大规模神经示踪研究，将小鼠大脑中已完成完整示踪的神经元数量提升了10倍。研究人员如今可下载并以三维形式浏览该数据集。这张迄今为止构建的最精细的小鼠大脑连接图谱，可让科学家以三维视角查看并探索这些蜿蜒的神经示踪轨迹。研究人员此次发现，小鼠大脑内的单个神经元不仅会在大脑半球间蜿蜒穿行，勾勒出繁复的分支形态，甚至可延伸出长达45厘米的纤细神经纤维。该图谱重构了小鼠大脑7000万神经元中超过300个的形态与位置。此前的单个神经元通路示踪研究，最多仅能完成数十个神经元的示踪工作。研究人员通过双光子显微镜（two-photon microscopy）的迭代成像流程，对经选择性标记的神经元进行了定位成像。实验中将小鼠大脑切割为200微米厚的脑片，每次对数十个神经元进行标记并完成成像。每颗成像的小鼠大脑可产生约50太字节的数据，其中包含已完成定位的神经元信息，研究人员可通过NeuronBrowser应用程序（访问地址：https://ml-neuronbrowser.janelia.org/）进行浏览。若有研究人员需要完整的原始数据集，可联系贾努利亚（Janelia）洽谈通过硬件传输方式获取的相关事宜。