MouseLight Neuron AA1351

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.珍利亚研究园区（Janelia）的科学家团队开展的大规模神经示踪工作，将小鼠大脑中已完成全流程示踪的神经元数量提升至原有的10倍。研究人员如今可下载并以三维形式浏览该数据集。 在小鼠大脑内，单个神经元会在脑半球间蜿蜒穿行，构建出如刺绣般精致的分支形态；研究人员此次还发现，神经元甚至能延伸出长达45厘米的纤细纤维。 科学家们可在这一迄今最为精细的小鼠大脑连接组图谱中，以三维视角观察并探索这些蜿蜒的神经示踪轨迹。该图谱重建了小鼠大脑7000万神经元中超过300个的形态与位置，而此前的单个神经元路径示踪研究仅能完成数十个神经元的示踪工作。 研究人员借助双光子显微镜（two-photon microscopy）的迭代成像流程，对选择性标记的神经元进行了绘制：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。每枚成像的大脑可产生约50太字节的数据，其中包含已完成标注的神经元，研究人员可通过https://ml-neuronbrowser.janelia.org/处的神经元浏览器（NeuronBrowser）应用进行浏览。 若有研究人员需要完整的原始数据集，可联系珍利亚研究园区（Janelia）协商通过硬件传输的方式获取。