BIG-2 mediates olfactory axon convergence to target glomeruli
BIG-2 mediates olfactory axon convergence to target glomeruli
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DOI：
10.1016/j.neuron.2008.01.023
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发表时间：
2008-03-27
期刊：
影响因子：
16.2
通讯作者：
Yoshihara, Yoshihiro
中科院分区：
文献类型：
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作者：
Kaneko-Goto, Tomomi;Yoshihara, Sei-ichi;Yoshihara, Yoshihiro
表达特定气味受体的嗅觉感觉神经元将轴突会聚到嗅球中的一些地形固定的肾小球上，从而建立气味地图。在这里，我们报告了BIG-2/contactin-4（一种属于免疫球蛋白超家族的轴突糖蛋白）在小鼠嗅觉感觉神经元亚群中表达。在嗅球中观察到肾小球排列的马赛克图案，具有强BIG-2阳性、弱阳性和阴性轴突终末，其与Kirrel 2和ephrin-A5的轴突终末重叠但不相同。在个体感觉神经元中，BIG-2表达水平与气味受体选择之间存在密切相关性。在BIG-2缺陷小鼠中，表达特定气味受体的嗅觉感觉神经元经常支配异位位置的多个肾小球。这些结果表明，BIG-2是嗅球功能气味地图形成和维持的关键轴突导向分子之一。
Olfactory sensory neurons expressing a given odorant receptor converge axons onto a few topographically fixed glomeruli in the olfactory bulb, leading to establishment of the odor map. Here, we report that BIG-2/contactin-4, an axonal glycoprotein belonging to the immunoglobulin superfamily, is expressed in a subpopulation of mouse olfactory sensory neurons. A mosaic pattern of glomerular arrangement is observed with strongly BIG-2-positive, weakly positive, and negative axon terminals in the olfactory bulb, which is overlapping but not identical with those of Kirrel2 and ephrin-A5. There is a close correlation between the BIG-2 expression level and the odorant receptor choice in individual sensory neurons. In BIG-2-deficient mice, olfactory sensory neurons expressing a given odorant receptor frequently innervate multiple glomeruli at ectopic locations. These results suggest that BIG-2 is one of the axon guidance molecules crucial for the formation and maintenance of functional odor map in the olfactory bulb.