Merlie J P, Hofler J G, Sebbane R
J Biol Chem. 1981 Jul 10;256(13):6995-9.
We have established conditions for the fractionation of cytoplasmic and membrane-bound polyribosomes from the clonal mouse cell line BC3H-1. Polyribosome fractions are obtained in good yield and purity. They are active in protein synthesis when incubated with nuclease-treated rabbit reticulocyte lysates, and we have demonstrated that the cytoplasmic and membrane-bound fractions direct the synthesis of distinctly different sets of proteins. Using immunoprecipitation and sodium dodecyl sulfate gel analysis, we have shown that the membrane-bound but not the cytoplasmic polyribosomes direct the synthesis of two protein species (Mr = 39,000 nd 42,000) which are homologous to the native alpha subunit of acetylcholine receptor. Peptide maps suggest that the two species synthesized in vitro may correspond to the nonglycosylated and glycosylated forms, respectively, of the alpha subunit.
我们已经建立了从小鼠克隆细胞系BC3H-1中分离细胞质和膜结合多核糖体的条件。多核糖体组分的产量和纯度都很高。当与经核酸酶处理的兔网织红细胞裂解物一起孵育时，它们在蛋白质合成中具有活性，并且我们已经证明细胞质和膜结合组分指导合成明显不同的蛋白质组。使用免疫沉淀和十二烷基硫酸钠凝胶分析，我们已经表明膜结合而非细胞质多核糖体指导合成两种蛋白质（分子量分别为39,000和42,000），它们与乙酰胆碱受体的天然α亚基同源。肽图表明体外合成的这两种蛋白质可能分别对应于α亚基的非糖基化和糖基化形式。
