Iurov Iu B, Liapunova N A
Mol Biol (Mosk). 1976 Sep-Oct;10(5):1085-93.
The rate of DNA replication and the distances between initiation sites (size of replicons) have been studied in human cultured fibroblasts. The modified Huberman and Riggs technique of DNA fiber autoradiography has been used: the pulse-labelled regions were analysed in DNA fibers preliminarily labelled along the whole length. This enabled us: a) to analyse the arrangement of replicons along the length of labelled DNA fibers with the lengths of 200-750 micron, reaching 2700 micron in some cases; b) to select only single DNA molecules for the analysis. This technique decreases the danger of a mistake when minor labelled regions belonging to different DNA molecules are referred to the same one. The rate of DNA replication varies from 0.2 to 1.2 micron/min, the average of 0.6 micron/min. This conforms with findings of other authors. The distances between initiation sites vary from 15 to 140 micron with the modal interval of 50-60 micron. This value is twice higher than those obtained by other authors. The possible reasons for such difference are discussed.
人们已经在人类培养成纤维细胞中研究了DNA复制速率以及起始位点之间的距离（复制子大小）。研究采用了改良的休伯曼和里格斯DNA纤维放射自显影技术：对预先沿全长进行标记的DNA纤维中的脉冲标记区域进行分析。这使我们能够：a）分析长度为200 - 750微米、某些情况下可达2700微米的标记DNA纤维全长上复制子的排列情况；b）仅选择单个DNA分子进行分析。该技术降低了将属于不同DNA分子的微小标记区域误归为同一个区域时出错的风险。DNA复制速率在0.2至1.2微米/分钟之间变化，平均为0.6微米/分钟。这与其他作者的研究结果相符。起始位点之间的距离在15至140微米之间变化，最常见的区间为50 - 60微米。该值比其他作者得到的值高出两倍。文中讨论了产生这种差异的可能原因。
