Radtke J, Unteregger G
Institute of Human Genetics, University of the Saar, Homburg, FRG.
FEBS Lett. 1988 Aug 29;236(2):367-71. doi: 10.1016/0014-5793(88)80057-7.
In the present study we investigated the binding behavior of nuclear proteins from human tumor cells to human placental DNA coupled on CNBr-activated Sepharose. When nuclear proteins soluble in 5 M urea prepared from serum-stimulated cells and containing the majority of the nonhistone proteins were applied onto a dsDNA column, next to several other proteins one prominent group consisting of at least 2 distinct proteins with a pI at 7 and a molecular mass near 24 kDa bound to DNA. The DNA-binding ability of one of them is lost on phosphorylation and is recovered after dephosphorylation using alkaline phosphatase. Additionally, normal human fibroblasts taken as controls exhibit comparatively low levels of these 24/7 proteins, indicating a particular function in tumor cells.
在本研究中，我们调查了来自人肿瘤细胞的核蛋白与偶联在溴化氰活化琼脂糖上的人胎盘DNA的结合行为。当将从血清刺激的细胞制备的、可溶于5M尿素且包含大多数非组蛋白的核蛋白应用于双链DNA柱时，除了其他几种蛋白质外，一个由至少2种不同蛋白质组成的突出组与DNA结合，这些蛋白质的等电点为7，分子量接近24kDa。其中一种蛋白质的DNA结合能力在磷酸化后丧失，并在使用碱性磷酸酶去磷酸化后恢复。此外，作为对照的正常人成纤维细胞显示这两种24/7蛋白的水平相对较低，表明它们在肿瘤细胞中具有特定功能。
