Institute of Neuroscience, State Key Laboratory of Neuroscience, Chinese Academy of Sciences, CAS Center for Excellence in Brain Science and Intelligence Technology, Shanghai Center for Brain Science and Brain-Inspired Technology, Shanghai, China.
University of Chinese Academy of Sciences, Beijing, China.
Elife. 2024 Feb 23;13:e85419. doi: 10.7554/eLife.85419.
Deciphering patterns of connectivity between neurons in the brain is a critical step toward understanding brain function. Imaging-based neuroanatomical tracing identifies area-to-area or sparse neuron-to-neuron connectivity patterns, but with limited throughput. Barcode-based connectomics maps large numbers of single-neuron projections, but remains a challenge for jointly analyzing single-cell transcriptomics. Here, we established a rAAV2-retro barcode-based multiplexed tracing method that simultaneously characterizes the projectome and transcriptome at the single neuron level. We uncovered dedicated and collateral projection patterns of ventromedial prefrontal cortex (vmPFC) neurons to five downstream targets and found that projection-defined vmPFC neurons are molecularly heterogeneous. We identified transcriptional signatures of projection-specific vmPFC neurons, and verified as a marker gene enriched in neurons projecting to the lateral hypothalamus, denoting a distinct subset with collateral projections to both dorsomedial striatum and lateral hypothalamus. In summary, we have developed a new multiplexed technique whose paired connectome and gene expression data can help reveal organizational principles that form neural circuits and process information.
破译大脑中神经元之间的连接模式是理解大脑功能的关键步骤。基于成像的神经解剖追踪可以识别区域到区域或稀疏的神经元到神经元的连接模式，但通量有限。基于条形码的连接组学可以绘制大量的单个神经元投射，但对于联合分析单细胞转录组学仍然是一个挑战。在这里，我们建立了一种 rAAV2-逆行条形码为基础的多路复用追踪方法，可在单细胞水平上同时表征投射组和转录组。我们发现腹内侧前额叶皮层（vmPFC）神经元到五个下游靶点的专用和侧枝投射模式，并发现投射定义的 vmPFC 神经元在分子上是异质的。我们确定了投射特异性 vmPFC 神经元的转录特征，并验证了作为一个在投射到外侧下丘脑的神经元中富集的标记基因，这表示一个具有到背内侧纹状体和外侧下丘脑的侧枝投射的独特亚群。总之，我们开发了一种新的多路复用技术，其配对的连接组和基因表达数据可以帮助揭示形成神经网络和处理信息的组织原则。
