St John James A, Key Brian
Department of Anatomy and Developmental Biology, School of Biomedical Sciences, The University of Queensland, Brisbane 4072, Australia.
Histochem J. 2002 Jun-Jul;34(6-7):281-9. doi: 10.1023/a:1023374407724.
Cell surface glycoconjugates have been implicated in the growth and guidance of subpopulations of primary olfactory axons. While subpopulations of primary olfactory neurons have been identified by differential expression of carbohydrates in the rat there are few reports of similar subpopulations in the mouse. We have examined the spatiotemporal expression pattern of glycoconjugates recognized by the lectin from Wisteria floribunda (WFA) in the mouse olfactory system. In the developing olfactory neuroepithelium lining the nasal cavity, WFA stained a subpopulation of primary olfactory neurons and the fascicles of axons projecting to the target tissue, the olfactory bulb. Within the developing olfactory bulb, WFA stained the synaptic neuropil of the glomerular and external plexiform layers. In adults, strong expression of WFA ligands was observed in second-order olfactory neurons as well as in neurons in several higher order olfactory processing centres in the brain. Similar, although distinct, staining of neurons in the olfactory pathway was detected with Dolichos biflorus agglutinin. These results demonstrate that unique subpopulations of olfactory neurons are chemically coded by the expression of glycoconjugates. The conserved expression of these carbohydrates across species suggests they play an important role in the functional organization of this region of the nervous system.
细胞表面糖缀合物与初级嗅觉轴突亚群的生长和导向有关。虽然已通过大鼠碳水化合物的差异表达鉴定出初级嗅觉神经元亚群，但关于小鼠中类似亚群的报道很少。我们研究了紫藤凝集素（WFA）识别的糖缀合物在小鼠嗅觉系统中的时空表达模式。在鼻腔内衬的发育中的嗅觉神经上皮中，WFA染色了初级嗅觉神经元的一个亚群以及投射到靶组织嗅球的轴突束。在发育中的嗅球内，WFA染色了肾小球层和外丛状层的突触神经毡。在成年小鼠中，在二级嗅觉神经元以及大脑中几个高级嗅觉处理中心的神经元中观察到WFA配体的强表达。用双花扁豆凝集素检测到嗅觉通路中神经元有类似但不同的染色。这些结果表明，嗅觉神经元的独特亚群通过糖缀合物的表达进行化学编码。这些碳水化合物在物种间的保守表达表明它们在神经系统该区域的功能组织中起重要作用。
