Ruegg M A, Stoeckli E T, Kuhn T B, Heller M, Zuellig R, Sonderegger P
Institute of Biochemistry, University of Zürich, Switzerland.
EMBO J. 1989 Jan;8(1):55-63. doi: 10.1002/j.1460-2075.1989.tb03348.x.
Using selective metabolic labelling in a compartmental cell culture system two proteins, denoted axonin-1 and axonin-2, were found to be secreted by axons of dorsal root ganglia neurons from chicken embryos. Based on its characteristic coordinates and spot morphology in two-dimensional gel electrophoresis, axonin-1 was detected in the cerebrospinal fluid and the vitreous fluid, axonin-1 was purified 476-fold to homogeneity by a four-step chromatographic procedure. The identity of the purified protein as axonin-1 was confirmed by immunological methods. Axonin-1 is a glycoprotein that subdivides into at least 16 immunologically similar isoelectric variants; their molecular weight range extends from 132 to 140 kd and their pI range from 5.3 to 6.2. In the vitreous fluid of the embryo, axonin-1 could first be detected on the embryonic day 5 and highest concentrations were measured during the second half of embryonic life; in the vitreous fluid of the adult chicken, concentrations were approximately 20 times lower. The early onset of secretion and the time course of expression suggest a role for axonin-1 in the development of the nervous system.
在一个区室化细胞培养系统中使用选择性代谢标记法，发现鸡胚背根神经节神经元的轴突分泌两种蛋白质，分别命名为轴突素-1和轴突素-2。基于其在二维凝胶电泳中的特征坐标和斑点形态，在脑脊液和玻璃体液中检测到了轴突素-1，通过四步色谱法将轴突素-1纯化了476倍，达到同质。通过免疫学方法证实了纯化后的蛋白质为轴突素-1。轴突素-1是一种糖蛋白，可细分为至少16种免疫相似的等电变体；它们的分子量范围从132到140 kd，等电点范围从5.3到6.2。在胚胎的玻璃体液中，轴突素-1最早在胚胎第5天被检测到，在胚胎后期测量到最高浓度；在成年鸡的玻璃体液中，浓度大约低20倍。分泌的早期开始和表达的时间进程表明轴突素-1在神经系统发育中起作用。
