Maundrell K, Scherrer K
Eur J Biochem. 1979 Sep;99(2):225-38. doi: 10.1111/j.1432-1033.1979.tb13249.x.
Ribonucleoprotein particles have been isolated from duck erythroblast nuclei using a procedure designed to produce maximal cytoplasmic dispersion with minimal release of endogenous hydrolytic enzymes. The RNA extracted from the purified nuclear ribonucleoprotein fraction is shown to contain globin messenger RNA sequences at a concentration comparable to that present in total nuclear RNA. The polypeptide composition of this fraction revealed by electrophoresis in two dimensions is complex, consisting of at least 65 acidic species and 21 basic species. Several lines of evidence suggest that these are authentic components of nuclear ribonucleoprotein. The so-called 'core' proteins of nuclear ribonucleoprotein which were previously shown to migrate as a single band on low-pH urea gels, and as six bands on sodium dodecyl sulphate gels are here shown to be considerably more complex being resolved by two-dimensional electrophoresis into a group of 15 basic and 6 more and less neutral polypeptides. Isoelectric focusing of nuclear ribonucleoprotein under non-denaturing conditions suggests that these latter species are not uniformly distributed along the pre-messenger RNA molecule.
已采用一种程序从鸭成红细胞核中分离出核糖核蛋白颗粒，该程序旨在使细胞质最大限度地分散，同时使内源性水解酶的释放量最小。从纯化的核核糖核蛋白组分中提取的RNA显示含有珠蛋白信使RNA序列，其浓度与总核RNA中的浓度相当。通过二维电泳揭示的该组分的多肽组成很复杂，由至少65种酸性物种和21种碱性物种组成。几条证据表明这些是核核糖核蛋白的真实成分。核核糖核蛋白的所谓“核心”蛋白，以前显示在低pH尿素凝胶上作为一条带迁移，在十二烷基硫酸钠凝胶上作为六条带迁移，在这里通过二维电泳显示要复杂得多，可分解为一组15种碱性和6种或多或少中性的多肽。在非变性条件下对核核糖核蛋白进行等电聚焦表明，后一类物种并非沿信使前体RNA分子均匀分布。
