RABINOVITCH M, PLAUT W
J Cell Biol. 1962 Dec;15(3):525-34. doi: 10.1083/jcb.15.3.525.
The incorporation of tritiated thymidine in Amoeba proteus was reinvestigated in order to see if it could be associated with microscopically detectable structures. Staining experiments with basic dyes, including the fluorochrome acridine orange, revealed the presence of large numbers of 0.3 to 0.5 micro particles in the cytoplasm of all cells studied. The effect of nuclease digestion on the dye affinity of the particles suggests that they contain DNA as well as RNA. Centrifugation of living cells at 10,000 g leads to the sedimentation of the particles in the centrifugal third of the ameba near the nucleus. Analysis of centrifuged cells which had been incubated with H(3)-thymidine showed a very high degree of correlation between the location of the nucleic acid-containing granules and that of acid-insoluble, deoxyribonuclease-sensitive labeled molecules and leads to the conclusion that cytoplasmic DNA synthesis in Amoeba proteus occurs in association with these particles.
为了探究变形虫中氚标记胸腺嘧啶核苷的掺入是否与显微镜下可检测到的结构相关，对其进行了重新研究。包括荧光染料吖啶橙在内的碱性染料染色实验表明，在所有研究的细胞的细胞质中存在大量0.3至0.5微米的颗粒。核酸酶消化对颗粒染料亲和力的影响表明，它们同时含有DNA和RNA。以10,000g的离心力对活细胞进行离心，会导致颗粒沉淀在靠近细胞核的变形虫离心端三分之一处。对用H(3)-胸腺嘧啶核苷孵育过的离心细胞进行分析，结果显示含核酸颗粒的位置与酸不溶性、对脱氧核糖核酸酶敏感的标记分子的位置之间存在高度相关性，从而得出结论：变形虫中的细胞质DNA合成与这些颗粒有关。
