Murti K G, Prescott D M
Mol Cell Biol. 1983 Sep;3(9):1562-6. doi: 10.1128/mcb.3.9.1562-1566.1983.
Using a method for obtaining DNA from 10 to 40 macronuclei for electron microscopy, we analyzed the structure of gene-sized, linear DNA molecules from S-phase macronuclei of two hypotrichous ciliates, Euplotes eurystomus and Styx sp. Three types of putative replicating intermediates were observed: (i) molecules with a bubble close to one end, (ii) molecules with single forks, and (iii) molecules with two forks. We conclude that: (i) each macronuclear DNA molecule replicates as an independent unit, (ii) the molecules contain an origin of replication close to one or both ends, and (iii) the mode of replication is bidirectional.
我们采用一种从10到40个大核中获取DNA用于电子显微镜观察的方法，分析了两种下毛目纤毛虫——宽口游仆虫和Styx sp.的S期大核中基因大小的线性DNA分子的结构。观察到三种类型的假定复制中间体：（i）一端附近有气泡的分子，（ii）有单叉的分子，以及（iii）有双叉的分子。我们得出以下结论：（i）每个大核DNA分子作为一个独立单元进行复制，（ii）这些分子在一端或两端附近含有一个复制起点，（iii）复制模式是双向的。
