Bremer J W, Busch H, Yeoman L C
Biochemistry. 1981 Mar 31;20(7):2013-7. doi: 10.1021/bi00510a042.
Nuclear actin (protein BJ) has been isolated from the chromatin of Novikoff hepatoma ascites cells and purified to homogeneity by selective extraction, Sepharose CL-6B chromatography, and preparative polyacrylamide gel electrophoresis. A comparison of nuclear and cytoplasmic actins from Novikoff hepatoma cells and rabbit muscle actin was made by amino acid analysis, isoelectric focusing/sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and two-dimensional peptide mapping procedures. By these criteria, all of the proteins compared are actins, but each is chemically distinct. It was concluded, therefore, that nuclear actin is similar to, but not identical with, cytoplasmic actin isolated from Novikoff hepatoma cells. A striking similarity in peptide charge and migration as shown by peptide map analysis was observed for nuclear and rabbit skeletal muscle actins. This may indicate that nuclear actin has the capacity for contractile function. In addition, the actins synthesized in Novikoff hepatoma cells may results from more than two structural genes.
核肌动蛋白（蛋白质BJ）已从诺维科夫肝癌腹水细胞的染色质中分离出来，并通过选择性提取、琼脂糖凝胶CL-6B柱层析和制备性聚丙烯酰胺凝胶电泳纯化至同质。通过氨基酸分析、等电聚焦/十二烷基硫酸钠-聚丙烯酰胺凝胶电泳和二维肽图分析方法，对诺维科夫肝癌细胞的核肌动蛋白和细胞质肌动蛋白以及兔肌肉肌动蛋白进行了比较研究。依据这些标准，所有被比较的蛋白质均为肌动蛋白，但各自在化学性质上有所不同。因此得出结论，核肌动蛋白与从诺维科夫肝癌细胞中分离出的细胞质肌动蛋白相似，但并不相同。肽图分析显示，核肌动蛋白与兔骨骼肌肌动蛋白在肽电荷和迁移方面存在显著相似性。这可能表明核肌动蛋白具有收缩功能。此外，诺维科夫肝癌细胞中合成的肌动蛋白可能由两个以上的结构基因产生。
