Developmental and Translational Neurobiology Center, Virginia Tech Carilion Research Institute, Roanoke, United States.
Department of Biological Sciences, Virginia Tech, Blacksburg, United States.
Elife. 2018 Feb 9;7:e33498. doi: 10.7554/eLife.33498.
It has long been thought that the mammalian visual system is organized into parallel pathways, with incoming visual signals being parsed in the retina based on feature (e.g. color, contrast and motion) and then transmitted to the brain in unmixed, feature-specific channels. To faithfully convey feature-specific information from retina to cortex, thalamic relay cells must receive inputs from only a small number of functionally similar retinal ganglion cells. However, recent studies challenged this by revealing substantial levels of retinal convergence onto relay cells. Here, we sought to identify mechanisms responsible for the assembly of such convergence. Using an unbiased transcriptomics approach and targeted mutant mice, we discovered a critical role for the synaptic adhesion molecule Leucine Rich Repeat Transmembrane Neuronal 1 (LRRTM1) in the emergence of retinothalamic convergence. Importantly, LRRTM1 mutant mice display impairment in visual behaviors, suggesting a functional role of retinothalamic convergence in vision.
长期以来，人们一直认为哺乳动物的视觉系统是组织成平行途径的，传入的视觉信号在视网膜中根据特征（例如颜色、对比度和运动）进行解析，然后以未混合的、特征特定的通道传输到大脑。为了忠实地将特征特定的信息从视网膜传递到皮层，丘脑中继细胞必须仅从少数功能相似的视网膜神经节细胞接收输入。然而，最近的研究通过揭示大量的视网膜对中继细胞的汇聚对此提出了挑战。在这里，我们试图确定负责这种汇聚组装的机制。使用无偏转录组学方法和靶向突变小鼠，我们发现突触粘附分子亮氨酸丰富重复跨膜神经元 1 (LRRTM1) 在视丘脑汇聚的出现中起着关键作用。重要的是，LRRTM1 突变小鼠在视觉行为中表现出障碍，表明视丘脑汇聚在视觉中具有功能作用。
