Berezney R
Department of Biological Sciences, State University of New York, Buffalo 14260.
Semin Cell Biol. 1991 Apr;2(2):103-15.
Studies of DNA replication associated with the nuclear matrix have led to a radically new view of replication at the macroscopic level. It is proposed that individual replicons and their associated replicational assemblies (replisomes) are clustered together during active replication by attachment to the nuclear matrix at special sites termed 'clustersomes'. Direct visualization of replication sites in permeabilized cells by fluorescence microscopy following biotin-11-dUTP incorporation provides support for this model. Discrete replication granules are observed with sizes and numbers consistent with each granule being a site of replicon cluster synthesis. Distinct patterns of these sites are seen in different periods of S-phase. Both the individual granules and their early and late S-phase dependent patterns are strikingly maintained following extraction of the cells for in situ nuclear matrix structures. Similar results were obtained when probing in vivo sites of replication following incorporation of 5-bromodeoxyuridine. The three-dimensional organization of these replicational granules (clustersomes) is studied using confocal light microscopy and an appropriate multidimensional image analysis system.
对与核基质相关的DNA复制的研究，在宏观层面上引发了一种全新的复制观点。有人提出，在活跃复制过程中，单个复制子及其相关的复制组装体（复制体）通过附着在称为“簇体”的特殊位点上的核基质而聚集在一起。在掺入生物素-11-dUTP后，通过荧光显微镜对通透细胞中的复制位点进行直接可视化，为该模型提供了支持。观察到离散的复制颗粒，其大小和数量与每个颗粒作为复制子簇合成位点一致。在S期的不同阶段可以看到这些位点的不同模式。在提取细胞以观察原位核基质结构后，单个颗粒及其依赖于S期早期和晚期的模式都得到了显著保留。当掺入5-溴脱氧尿苷后探测体内复制位点时，也获得了类似的结果。使用共聚焦光学显微镜和适当的多维图像分析系统研究了这些复制颗粒（簇体）的三维组织。
