MouseLight Neuron AA1323

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.

Janelia团队的科学家开展了一项大规模神经追踪研究，将小鼠大脑中完全追踪的神经元数量提升至原来的10倍。研究人员如今可对该数据进行三维下载与浏览。在小鼠大脑内部，单个神经元呈锯齿状穿梭于半球之间，形成刺绣般的分支图案；研究人员还发现，这些神经元甚至能延伸出长达45厘米的细长纤维。科学家可在这张迄今为止最详尽的小鼠大脑连接图谱中，以三维方式观察并探索这些游走的神经轨迹。该图谱重建了小鼠大脑7000万个神经元中300余个的形态与位置——此前，单个神经元路径追踪的成果最多仅为数十个。选择性标记的神经元通过双光子显微镜（two-photon microscopy）的迭代过程完成绘制：大脑被切成200微米厚的切片，每次标记并成像数十个神经元。每个成像大脑产生约50太字节（TB）的数据，其中包含已绘制的神经元，可通过NeuronBrowser应用浏览，网址为https://ml-neuronbrowser.janelia.org/。对完整原始数据集感兴趣的研究人员可联系Janelia，商讨通过硬件传输获取该数据集的事宜。