Zini N, Mazzotti G, Santi P, Rizzoli R, Galanzi A, Rana R, Maraldi N M
Instituto di Citomorfologia Normale e Patologica del C.N.R, Bologna, Italy.
Histochemistry. 1989;91(3):199-204. doi: 10.1007/BF00490133.
The rat liver nuclear matrix, obtained by endogenous nuclease digestion and extraction with low and high ionic strength media, contains residual DNA fragments that are considered to represent the attachment sites of the chromatin domains to the nucleoskeleton. These sites, protected against nuclease digestion by their binding with the nucleoskeleton proteins, should be either mainly linked to the peripheral lamina or to the inner nuclear matrix. The DNA fragment distribution at the level of the different components of the nuclear matrix has been evaluated in samples embedded in Epon and in hydrophilic resins by means of the DNase-gold technique. The labeling obtained suggests that the chromatin loops are prevailingly associated with the interior of the matrix; in fact about twice of the label is present in the inner matrix with respect to the peripheral lamina area. These results confirm the hypothesis that in interphase the chromatin maintains an organization similar to that of chromosomes, with loops radiating from a central scaffold, instead of being mainly attached to the lamina as otherwise suggested.
通过用低离子强度和高离子强度介质进行内源性核酸酶消化和提取获得的大鼠肝核基质，含有残留的DNA片段，这些片段被认为代表染色质结构域与核骨架的附着位点。这些位点通过与核骨架蛋白结合而免受核酸酶消化，它们应该主要与外周核纤层或内核基质相连。借助于DNase-金技术，已经在包埋于环氧树脂和亲水性树脂中的样品中评估了核基质不同组分水平上的DNA片段分布。所获得的标记表明染色质环主要与基质内部相关联；事实上，相对于外周核纤层区域，内基质中的标记大约是其两倍。这些结果证实了这样的假设，即在间期染色质保持与染色体相似的组织形式，环从中央支架辐射而出，而不是如其他所认为的那样主要附着于核纤层。
