Identification of cell-type specific visual circuits in the ventral lateral geniculate nucleus

项目总结 有关视觉世界的信息由视网膜捕获，并由视网膜神经节细胞(RGC)传输到 哺乳动物大脑中不同的视黄醇受体区域，包括丘脑，下丘脑， 和中脑区域。这些远距离视网膜投射有组织逻辑，其中RGC， 在形态和功能上有30多个不同的亚型，投射到不同的 有时是相互排斥的视网膜区。这些视网膜前核中的许多对于 特定视觉行为的执行。了解视觉信息是如何处理和传输的 从视网膜到这些大脑区域，需要详细描述这两个区域中的全部细胞群 区域以及对它们组装成的电路类型的调查。这需要我们将一个 视网膜和大脑中的细胞“部件清单”。对于皮质下视觉系统的某些部分，例如 目录已存在。然而，对于一些视黄酸受体核，细胞部件列表要么特征不佳 或者失踪。其中一个特征仍然很差的区域是腹侧膝状核(VLGN)， 啮齿动物的第三大视黄醇受体区域。因此，我们的目标是应用最先进的单细胞 采用跨突触病毒跟踪的分辨率转录测序，以无偏见的方式识别ALL 视网膜节内视黄醇受体细胞的类型。在初步研究中已经确定了两种这样的细胞类型 (Pvalb+和Penk+细胞)，令人惊讶的是，这些细胞类型占据了vLGN不同的相邻亚层。这些 解剖学划分表明该区域视网膜受体细胞的亚型特异性板层分布 对于在并行通道中接收、处理和发送光导出信号可能很重要 大脑。我们将通过确定这两个子类型的特定输入和输出来检验这一假设 VLGN神经元。

PROJECT SUMMARY Information about the visual world is captured by the retina and transmitted by retinal ganglion cells (RGCs) to a diverse array of retino-recipient regions of the mammalian brain, including those in thalamic, hypothalamic, and midbrain regions. There is an organizational logic to these long-range retinal projections where RGCs, of which there are more than three dozen morphologically and functionally distinct subtypes, project to distinct and sometimes mutually exclusive retinorecipient regions. Many of these retinorecipient nuclei are critical to the execution of specific visual behaviors. To understand how visual information is processed and transmitted from the retina to these brain regions requires a detailed characterization of the full cohort of cells in both regions and an investigation into the types of circuits they are assembled into. This requires us to catalogue a cellular “parts list” in both the retina and brain. For some parts of the subcortical visual system, such a catalogue exists. However, for some retino-recipient nuclei the cellular parts list is either poorly characterized or missing. One such region that remains poorly characterized is the ventral lateral geniculate nucleus (vLGN), the third largest retino-recipient region in rodents. Therefore, our goal is to apply state-of-the-art single cell resolution transcriptomic sequencing with trans-synaptic viral tracing to identify, in an unbiased fashion, all types of retino-recipient cells in the vLGN. Two such cell types have been identified in preliminary studies (Pvalb+ and Penk+ cells) and surprisingly, these cell types occupy distinct, adjacent sublamina of vLGN. These anatomical divisions suggest that subtype-specific laminar distribution of retino-recipient cells in this region may be important for receiving, processing, and transmitting light-derived signals in parallel channels through the brain. We will test this hypothesis by identifying the specific inputs and outputs of these two subtypes of vLGN neurons.