Solovéva L V, Svetlova M P, Krutilina R I, Rozanov Y M, Stein G I, Tomilin N V
Tsitologiia. 1997;39(2-3):138-49.
Current methods of physical mapping allow the estimation of genomic distances (i.e. DNA contents) from linear distances between DNA markers in interphase nuclei, and in this study we estimated the size of focal centers of DNA replication in cultured S-phase human cells. Our results indicate that the conformation of S-phase chromosome fibres in the range of contour lengths 0.1-3.0 microns fits the random walk model and, therefore, the quantitative methods of interphase mapping can be applied to the estimation of sizes of replication units. The obtained data show the existence of multiple non-clustered small units less than 150 kb in size, equivalent to small replicons detected by fiber DNA radioautography, and also a significant fraction of big units more than 500 kb in size, representing groups of small replicons and/or big replicons. These big units are detected as chains of small replication foci, probably reflecting the structural chromatin organization in well-known loop domains, since the experimentally induced decrease of replicons to the average size 12 kb does not lead to any change in the pattern of indicated chains.
当前的物理作图方法能够根据间期核中DNA标记之间的线性距离来估计基因组距离（即DNA含量），在本研究中，我们估计了培养的S期人类细胞中DNA复制焦点的大小。我们的结果表明，轮廓长度在0.1 - 3.0微米范围内的S期染色体纤维的构象符合随机游走模型，因此，间期作图的定量方法可用于估计复制单元的大小。获得的数据显示存在多个大小小于150 kb的非聚集小单元，等同于通过纤维DNA放射自显影检测到的小复制子，同时也有相当一部分大小超过500 kb的大单元，代表小复制子组和/或大复制子。这些大单元被检测为小复制焦点链，可能反映了著名的环域中的染色质结构组织，因为实验诱导的复制子平均大小降至12 kb不会导致所示链的模式发生任何变化。
