Greenberger L M, Williams S S, Georges E, Ling V, Horwitz S B
Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY 10461.
J Natl Cancer Inst. 1988 Jun 1;80(7):506-10. doi: 10.1093/jnci/80.7.506.
P-glycoprotein (P-gp) plays a fundamental role in multidrug resistance. The quantity of P-gp relates to the degree of drug resistance. A comparison was made between P-gps in mouse and hamster cell lines in both Laemmli and modified Fairbanks gel systems. Both proteins are derived from precursors of similar size that undergo differential N-linked glycosylation. The electrophoretic mobility and the amount of P-gp are remarkably dependent on the conditions of analysis. Notably, boiling P-gp before Laemmli gel electrophoresis decreases its mobility by an amount that is equivalent to approximately equal to 15 kDa and results in an apparent diminution in the amount of protein. The latter effect can give a false impression concerning the quantity of P-gp in cells.
P-糖蛋白（P-gp）在多药耐药中起关键作用。P-糖蛋白的量与耐药程度相关。在Laemmli和改良的Fairbanks凝胶系统中，对小鼠和仓鼠细胞系中的P-糖蛋白进行了比较。这两种蛋白质均来源于大小相似的前体，它们经历了不同的N-连接糖基化。P-糖蛋白的电泳迁移率和量显著依赖于分析条件。值得注意的是，在Laemmli凝胶电泳前将P-糖蛋白煮沸会使其迁移率降低约相当于15 kDa的量，并导致蛋白质含量明显减少。后一种效应可能会给细胞中P-糖蛋白的量造成错误印象。
