Fliegner K H, Kaplan M P, Wood T L, Pintar J E, Liem R K
Department of Pathology, Columbia University College of Physicians and Surgeons, New York, New York 10032.
J Comp Neurol. 1994 Apr 8;342(2):161-73. doi: 10.1002/cne.903420202.
While neurofilaments have long been considered early markers of neuronal differentiation, they cannot be detected in most newly postmitotic neurons of the developing central nervous system (CNS). Here we show that these neurons already express the neuronal intermediate filament protein alpha-internexin at high levels. alpha-internexin is expressed by most, if not all, neurons as they begin differentiation and shows no overlap with vimentin, whose expression in the CNS is restricted to mitotic neuronal precursors. In the adult, alpha-internexin is the only intermediate filament gene expressed by the cerebellar granule cells, the source of the thin-caliber parallel fibers; conversely, neurofilament proteins are highly expressed in large neurons, which express alpha-internexin at low levels. These data suggest that neuronal intermediate filaments may regulate axonal stability and/or diameter through changes not only in their number, but also in their subunit composition.
虽然神经丝长期以来一直被视为神经元分化的早期标志物，但在发育中的中枢神经系统（CNS）的大多数新的有丝分裂后神经元中却无法检测到它们。在这里，我们表明这些神经元已经高水平表达神经元中间丝蛋白α-互连蛋白。α-互连蛋白在大多数（如果不是全部）神经元开始分化时就已表达，并且与波形蛋白没有重叠，波形蛋白在中枢神经系统中的表达仅限于有丝分裂的神经元前体。在成体中，α-互连蛋白是小脑颗粒细胞（细口径平行纤维的来源）唯一表达的中间丝基因；相反，神经丝蛋白在大神经元中高度表达，而这些大神经元中α-互连蛋白的表达水平较低。这些数据表明，神经元中间丝可能不仅通过其数量的变化，还通过其亚基组成的变化来调节轴突的稳定性和/或直径。
