论文部分内容阅读
通过人工合成大鼠巢蛋白（Nestin）C-末端的一段20肽，制备得到了抗巢蛋白的抗体--Anti-Nes－2。我们发现该抗体除了能识别小鼠240kD的巢蛋白条带外，还特异性识别另一分子量约为50kD的蛋白条带。蛋白印迹反应提示，该50kD蛋白可能与神经细胞的增殖和分化相关。经分高纯化和N-端氨基酸序列测定证实：该50kD蛋白为微管蛋白（α-tubulin）。我们发现，通过免疫吸附反应该抗体只能被脑中分离的微管蛋白所特异性吸附，而不能被肺来源的微管蛋白所吸附。蛋白印迹反应结果还表明：与一般的α-和β-tubulin在各种组织和细胞株中都有表达的情况不同，该50kD蛋白只在小鼠发育不同时期的脑组织及神经前体细胞中特异性表达，并随神经发育过程其表达县不断增加；而在其它组织和所考察的细胞株中都不表达。鉴于以上结果，我们认为Anti－Nes－2抗体所识别的50kD蛋白是神经细胞特异的α－tubulin，并可能是一种神经元特异的α-tubulin翻译后加工产物。
An anti-Nestin antibody Anti-Nes-2 was prepared by artificially synthesizing a 20-mer peptide from the C-terminal of rat nestin. We found that this antibody specifically recognizes another protein band of about 50 kD in addition to the mouse 240 kD nestin band. Western blotting indicated that the 50 kD protein may be involved in the proliferation and differentiation of neural cells. The sub-high purification and N-terminal amino acid sequence analysis confirmed that the 50kD protein is α-tubulin. We found that this antibody can only be specifically adsorbed by microtubules isolated from the brain by immunoadsorption reactions and not by lung-derived tubulin. Western blotting results also showed that, unlike the common α-and β-tubulin expression in various tissues and cell lines, the 50kD protein only in the development of mice in different stages of brain tissue and neural progenitor cells Specific expression, and its expression of the county along with the neural development of the county continues to increase; in other tissues and investigated cell lines are not expressed. In view of the above results, we consider that the 50 kD protein recognized by Anti-Nes-2 antibody is a neuron-specific α-tubulin and may be a neuron-specific α-tubulin post-translational product.