Ravi Namasivayam, Sanchez-Guardado Luis, Lois Carlos, Kelsch Wolfgang
Central Institute of Mental Health, Medical Faculty Mannheim, Heidelberg University, 68159, Mannheim, Germany.
Division of Biology and Biological Engineering, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA, 91125, USA.
Cell Mol Life Sci. 2017 Mar;74(5):849-867. doi: 10.1007/s00018-016-2367-y. Epub 2016 Sep 30.
The mammalian olfactory bulb is a forebrain structure just one synapse downstream from the olfactory sensory neurons and performs the complex computations of sensory inputs. The formation of this sensory circuit is shaped through activity-dependent and cell-intrinsic mechanisms. Recent studies have revealed that cell-type specific connectivity and the organization of synapses in dendritic compartments are determined through cell-intrinsic programs already preset in progenitor cells. These progenitor programs give rise to subpopulations within a neuron type that have distinct synaptic organizations. The intrinsically determined formation of distinct synaptic organizations requires factors from contacting cells that match the cell-intrinsic programs. While certain genes control wiring within the newly generated neurons, other regulatory genes provide intercellular signals and are only expressed in neurons that will form contacts with the newly generated cells. Here, the olfactory system has provided a useful model circuit to reveal the factors regulating assembly of the highly structured connectivity in mammals.
哺乳动物的嗅球是一种前脑结构，位于嗅觉感觉神经元下游仅一个突触处，负责对感觉输入进行复杂的计算。这种感觉回路的形成是通过活动依赖和细胞内在机制塑造的。最近的研究表明，细胞类型特异性连接以及树突区室中突触的组织是由祖细胞中预先设定的细胞内在程序决定的。这些祖细胞程序产生了具有不同突触组织的神经元类型内的亚群。不同突触组织的内在决定形成需要来自接触细胞的与细胞内在程序相匹配的因子。虽然某些基因控制新生成神经元内的布线，但其他调节基因提供细胞间信号，并且仅在将与新生成细胞形成接触的神经元中表达。在这里，嗅觉系统提供了一个有用的模型回路，以揭示调节哺乳动物高度结构化连接组装的因子。
