微管蛋白的分离鉴定及其在抗癌药物筛选中的应用

ISOLATION AND IDENTIFICATION OF MICROTUBULE PROTEIN AND ITS APPLICATION IN ANTICANCER DRUG SCREENING

摘要: 用两个循环聚合——解聚的方法,从猪脑分离到部分纯化的微管蛋白,在聚丙烯酰胺凝胶电泳图谱上显示两个主峰带,即。微管蛋白(M:W.58,000)和β微管蛋白(M.W.54,000)。在ATP或GTP存在的MES缓冲液中37℃保温b微管蛋白迅速聚合为微管,A 350呈典型S形聚合曲线。在电子显微镜下显示网状微管结构。抗癌药物筛选实验表明:秋水仙碱明显抑制微管聚合;长春新碱低浓度(0.75-6μM)抑制微管蛋白聚合,高浓度(>6μM)时导致微管蛋白聚集(Aggregation),且在低温下不解聚。三尖杉酯类生物碱对微管蛋白的聚合及解聚未显示明显的影响。

Abstract: Partially purified microtubule protein was prepared from porcine brain by two cycle polymerization-depolymerizations in MES buffer. Two main bands, α-tubulin (M. W. 58,000)and β-tubulin (M. W. 54,000) were obtained on SDS polyacrylamide gel electrophoresis. ATP and GTP, at a concentration of 1 mM was found to have comparable activity in supporting microtubule polymerization. The effect of vincristine on the microtubule protein was examined. Low concentration of vincristine (0.75 μM)inhibited the microtubule polymerization, but high concentration (24 μM)induced aggregation which could not depolymerize at low temperature (0—4℃). Harringtonine, homoharringtonine and isoharringtonine did not show significant activity on this model.