Miles K, Schwartz S A
Exp Cell Biol. 1979;47(2):81-91. doi: 10.1159/000162925.
Through the use of two different DNA-protein reconstitution methods, we examined the potential role of type C RNA tumor virus proteins as putative regulatory agents in the control of virus expression. Rauscher murine leukemia virus, purified from chronically infected rat cell cultures, was iodinated in vitro with [125I], and dissociated in a nondetergent high-ionic-strength urea-containing buffer. The chemically separated [125I]-labeled viral polypetides were reconstituted with purified DNA by affinity column chromatography and by gradient dialysis renaturation. In both instances, no detectable amount of radioactivity specifically bound to double-stranded DNA of any origin. This observation was in contrast to the binding behavior of identically prepared and radiolabeled, nonhistone chromosomal proteins purified from rat cell nuclei. This finding may rule out, in eukaryotic cells, a well-described prokarytoic regulatory mechanism for the control of integrated viral gene expression.
通过使用两种不同的DNA-蛋白质重组方法，我们研究了C型RNA肿瘤病毒蛋白作为假定的调节因子在控制病毒表达中的潜在作用。从长期感染的大鼠细胞培养物中纯化的劳舍尔鼠白血病病毒，在体外用[125I]进行碘化，并在不含洗涤剂的高离子强度含尿素缓冲液中解离。通过亲和柱色谱法和梯度透析复性法，将化学分离的[125I]标记的病毒多肽与纯化的DNA重组。在这两种情况下，均未检测到有可检测量的放射性特异性结合到任何来源的双链DNA上。这一观察结果与从大鼠细胞核中纯化的相同制备和放射性标记的非组蛋白染色体蛋白的结合行为形成对比。这一发现可能排除了真核细胞中一种已被充分描述的用于控制整合病毒基因表达的原核调节机制。
