Cutforth Tyler, Moring Laurie, Mendelsohn Monica, Nemes Adriana, Shah Nirao M, Kim Michelle M, Frisén Jonas, Axel Richard
Howard Hughes Medical Institute and Center for Neurobiology and Behavior, College of Physicians and Surgeons, Columbia University, New York, NY 10032, USA.
Cell. 2003 Aug 8;114(3):311-22. doi: 10.1016/s0092-8674(03)00568-3.
Olfactory sensory neurons expressing a given odorant receptor (OR) project with precision to specific glomeruli in the olfactory bulb, generating a topographic map. In this study, we demonstrate that neurons expressing different ORs express different levels of ephrin-A protein on their axons. Moreover, alterations in the level of ephrin-A alter the glomerular map. Deletion of the ephrin-A5 and ephrin-A3 genes posteriorizes the glomerular locations for neurons expressing either the P2 or SR1 receptor, whereas overexpression of ephrin-A5 in P2 neurons results in an anterior shift in their glomeruli. Thus the ephrin-As are differentially expressed in distinct subpopulations of neurons and are likely to participate, along with the ORs, as one of a complement of guidance receptors governing the targeting of like axons to precise locations in the olfactory bulb.
表达特定气味受体（OR）的嗅觉感觉神经元精确投射到嗅球中的特定嗅小球，形成一张拓扑图谱。在本研究中，我们证明表达不同OR的神经元在其轴突上表达不同水平的ephrin-A蛋白。此外，ephrin-A水平的改变会改变嗅小球图谱。删除ephrin-A5和ephrin-A3基因会使表达P2或SR1受体的神经元的嗅小球位置后移，而在P2神经元中过表达ephrin-A5会导致其嗅小球向前移位。因此，ephrin-A在不同的神经元亚群中差异表达，并且可能与OR一起，作为引导受体的补充之一，参与控制同类轴突靶向嗅球中精确位置的过程。
