Faivre-Sarrailh C, Gennarini G, Goridis C, Rougon G
Laboratoire de la Différenciation Cellulaire, URA CNRS 179, Faculté des Sciences de Luminy, Marseille, France.
J Neurosci. 1992 Jan;12(1):257-67. doi: 10.1523/JNEUROSCI.12-01-00257.1992.
The distribution of the F3/F11 neuronal cell surface molecule was investigated in the developing and adult mouse cerebellum by immunocytochemistry at the light and electron microscopic levels. F3/F11 was confined to subsets of neuronal types, since the Purkinje cell body and dendritic arborization as well as the stellate cells were not immunoreactive. In the young developing cerebellum, the granule cell axons strongly express F3/F11 as soon as they begin to grow, consistent with a functional role in promoting directional outgrowth of neuronal processes. In 10-d-old and adult cerebella, the granule cell bodies and dendrites were not immunoreactive whereas the parallel fibers, which are the granule cell axons, were labeled including in their presynaptic varicosities. By contrast, dendrites, cell bodies, and axons of Golgi cells were labeled by anti-F3 antibodies. Hence, F3/F11 can either be expressed throughout the cell or be polarized to the axons. This raises the question of how segregation of the glypiated F3/F11 molecule between different subcellular compartments depending on the type of neuron is achieved. F3/F11 was found to be present at three types of synaptic sites, suggesting that it might play a role in the formation and maintenance of synapses. However, in each type of synpase, F3/F11 was present at only the pre- or postsynaptic site, never at both: the parallel fiber varicosities contained F3/F11 whereas the postsynaptic compartment in contact, that is, the Purkinje cell dendritic spines, did not. The granule cell dendrites were unlabeled while the mossy fiber terminals contacting them were immunoreactive, and finally, the Golgi cell dendrites and dendritic spines were labeled while the presynaptic compartment contacting them was not. If F3/F11 functions as an adhesion molecule in vivo as indicated by in vitro assays, F3/F11-mediated adhesion is likely to be heterophilic.
通过光镜和电镜免疫细胞化学方法，研究了发育中和成年小鼠小脑中F3/F11神经元细胞表面分子的分布情况。F3/F11局限于特定类型的神经元亚群，因为浦肯野细胞体、树突分支以及星状细胞均无免疫反应性。在发育早期的小脑中，颗粒细胞轴突一旦开始生长就强烈表达F3/F11，这与促进神经元突起定向生长的功能作用一致。在10日龄和成年小脑中，颗粒细胞体和树突无免疫反应性，而作为颗粒细胞轴突的平行纤维被标记，包括其突触前膨体。相比之下，高尔基细胞的树突、细胞体和轴突被抗F3抗体标记。因此，F3/F11既可以在整个细胞中表达，也可以极化到轴突上。这就提出了一个问题，即根据神经元类型，糖基化的F3/F11分子如何在不同亚细胞区室之间实现分离。发现F3/F11存在于三种类型的突触部位，表明它可能在突触的形成和维持中发挥作用。然而，在每种类型的突触中，F3/F11仅存在于突触前或突触后部位，从未同时存在于两者：平行纤维膨体含有F3/F11，而与之接触的突触后区室，即浦肯野细胞树突棘则没有。颗粒细胞树突未被标记，而与之接触的苔藓纤维终末具有免疫反应性，最后，高尔基细胞树突和树突棘被标记，而与之接触的突触前区室则没有。如果如体外实验所示，F3/F11在体内作为一种粘附分子发挥作用，那么F3/F11介导的粘附很可能是异嗜性的。
