MouseLight Neuron AA0748

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. Researchers interested in the complete raw data set should contact Janelia to discuss obtaining it via hardware transfer.贾内利亚研究所（Janelia）的科学家团队开展了一项大规模神经追踪研究，将小鼠大脑中已完整追踪的神经元数量提升了10倍。 研究人员如今可下载并三维浏览该数据集。 在小鼠大脑内部，单个神经元会曲折穿梭于大脑半球之间，织就繁复的分支结构；研究团队此次还发现，神经元甚至可延伸出长达45厘米的纤细纤维。 这是目前已构建的最精细小鼠大脑连接图谱，科学家可通过三维方式查看并探索这些蜿蜒的神经追踪轨迹。 该图谱重建了小鼠大脑7000万神经元中300余个的形态与位置。此前的同类研究最多仅能追踪数十个神经元的通路。 研究通过双光子显微镜（two-photon microscopy）的迭代成像流程，完成了对选择性标记神经元的图谱构建。 实验中将小鼠大脑切割为200微米厚的切片，每次仅标记并成像数十个神经元。 每只完成成像的大脑可产生约50太字节的数据，其中包含已完成图谱标注的神经元，研究人员可通过NeuronBrowser应用程序进行浏览。 若有研究人员需要完整的原始数据集，可联系贾内利亚研究所洽谈通过硬件传输的方式获取。