【摘要】 乌本苷是质膜Na~+、K~+ATP酶的特异性抑制剂。在3.0 mM K~+的培养液中,0.5mM浓度的乌本苷可完全抑制野生型Wg 3-h细胞的生长;而在0.3 mM K~+的培养液中,则只需0.025 mM的药物浓度即可。以5 mM乌本苷为选择标准,本文作者以一步群选法从Wg 3-h细胞中选出16个抗性克隆(Ouα~R)。Ouα~R表型稳定,在无药物选择压力长达一年之久的情况下仍保持不变。比较Ouα~s和Ouα~R细胞的Na~+/K~+运输,发现Ouα~R细胞对乌本苷抑制作用的敏感性降低。Ouα~R细胞与Ouα~s细胞两者在生长速度、对培养液的需求,对HAT培养液和洋地黄毒苷的敏感性方面,均无明显差异。运用扫描电镜技术,观察到一些在光学显微镜下所见不到的乌本苷对细胞的影响。本文还就蛋白质双向电泳分析的结果,对Ouα~R的本质作了探讨。Ouα~R遗传标记,可用于体细胞融合中杂种细胞的筛选。更多还原

【Abstract】 Sixteen mutants resistant to ouabain,which inhibits the plasma membrane Na~++K~+-ATPase,have been isolated fromWg3-h.Ouabain at concentrations of 0.5mM with 3.0 mM K~+,or 0.025 mMwith 0.3 mM K~+,inhibits the growthof the wildtype cells and is ultimatelycytotoxic.Clones 10-fold more resistantthan wild-type in terms of dose wereobtained by single-step selection from awild-type population in the presence ofouabain.The phenotypes of ouabain-re-sistant(Ouα~R)clones are reproduciblewith high fidelity and stable over one-year interval of growth in the absenceof the selecting compound.Wild-typeand Ouα~R Wg3-h cell clones were com-pared with respect to their susceptibilityto ouabain inhibition of K~+ uptake bywhole cells.Ouα~R cells are less sensitiveto ouabain inhibition on active Na~+,K~+transport than are wild type cells.Ouα~Rcells are fully sensitive to HAT mediumand digitoxin just like the cells of theoriginal cell line.There are no signifi-cant differences in growth rate and re-quirement of growth conditions betweenthe Ouα~R cells and Ouα~S cells. The morphological features were ob-served by scanning electronic microscopy.The nature of Ouα~R is discussed withthe result of 2 D-gel electrophoresis. The Ouα~R marker can be useful forselection of somatic cell hybrids.更多还原