Huberman Andrew D, Wei Wei, Elstrott Justin, Stafford Ben K, Feller Marla B, Barres Ben A
Department of Neurobiology, Stanford University School of Medicine, Palo Alto, CA 94305, USA.
Neuron. 2009 May 14;62(3):327-34. doi: 10.1016/j.neuron.2009.04.014.
Motion detection is an essential component of visual processing. On-Off direction-selective retinal ganglion cells (On-Off DSGCs) detect objects moving along specific axes of the visual field due to their precise retinal circuitry. The brain circuitry of On-Off DSGCs, however, is largely unknown. We report a mouse with GFP expressed selectively by the On-Off DSGCs that detect posterior motion (On-Off pDSGCs), allowing two-photon targeted recordings of their light responses and delineation of their complete map of central connections. On-Off pDSGCs project exclusively to the dorsal lateral geniculate nucleus and superior colliculus and in both targets form synaptic lamina that are separate from a lamina corresponding to non-DSGCs. Thus, individual On-Off DSGC subtypes are molecularly distinct and establish circuits that map specific qualities of directional motion to dedicated subcortical areas. This suggests that each RGC subtype represents a unique parallel pathway whose synaptic specificity in the retina is recapitulated in central targets.
运动检测是视觉处理的一个重要组成部分。开-关方向选择性视网膜神经节细胞（On-Off DSGCs）由于其精确的视网膜神经回路，能够检测沿视野特定轴移动的物体。然而，On-Off DSGCs的大脑神经回路在很大程度上尚不清楚。我们报告了一只小鼠，其绿色荧光蛋白（GFP）由检测向后运动的On-Off DSGCs（On-Off pDSGCs）选择性表达，这使得我们能够对它们的光反应进行双光子靶向记录，并描绘出它们完整的中枢连接图谱。On-Off pDSGCs仅投射到背侧外侧膝状体核和上丘，并且在这两个靶点中都形成了与对应于非DSGCs的层分开的突触层。因此，单个On-Off DSGC亚型在分子上是不同的，并建立了将定向运动的特定特征映射到专用皮质下区域的神经回路。这表明每个视网膜神经节细胞（RGC）亚型代表一条独特的平行通路，其在视网膜中的突触特异性在中枢靶点中得到重现。
