Characterization of a newly-discovered cell type family in the retina

描述（申请人提供）：神经系统功能需要不同神经元亚型之间的精确连接。在视网膜中，对视网膜神经节细胞（RGCs）的个体亚型如何形成具有特定功能的层限制电路(如检测物体运动（称为方向选择性[DS]）的理解取得了进展。人们对密切相关的神经元集（家族）是如何组织和连接起来处理相关视觉信息的了解较少。最近，我发现了一个新的RGC家族的多个成员，包括两个以前描述过的RGC亚型。这些细胞与已知的DS细胞J-RGCs表现出惊人的形态和分子相似性，但它们各自的树突场区域不同。我把这些新细胞称为“j家族”。由于树突场ara与感觉敏锐度密切相关，因此j家族可以在一定的空间分辨率范围内处理物体运动。在这里，我提出了一系列的实验，以更好地了解这个新的细胞类型家族，包括他们的相对组织，感受野特性，和发展。我还将测试候选分子在j细胞回路形成和功能中的作用。这些研究将揭示相关神经元集发育的基本原理，并阐明中枢神经系统中不同细胞类型家族之间感觉处理的相似方面是如何被委派的。

DESCRIPTION (provided by applicant): Precise connectivity between diverse neuronal subtypes is required for nervous system function. In the retina, progress has been made understanding how individual subtypes of retinal ganglion cells (RGCs) form lamina-restricted circuits with specific functions, like detection of object movement (termed direction selectivity [DS]). Less is known about the way closely related neuronal sets (families) are organized and connected to process related visual information. Recently, I discovered multiple members of a new RGC family, including two previously undescribed RGC subtypes. These cells show striking morphological and molecular similarity to a known DS cell called J-RGCs, but differ in their respective dendritic field areas. I call these new cells the "J-family". Because dendritic field ara correlates strongly with sensory acuity, the J-family may process object motion over a range of spatial resolutions. Here I propose a series of experiments to better understand this novel cell type family, including their relative organization, receptive field properties, and development. I will also test the role of candidate molecules in J-cell circuit formation and function. These studies will reveal fundamental principles in the development of a related neuronal set, and elucidate how similar aspects of sensory processing may be delegated across divergent cell type families in the CNS.