S''iakste N I, Budylin A V
Mol Gen Mikrobiol Virusol. 1990 Jul(7):21-4.
Influence of activation of Ca2+/Mg2(+)-dependent, Mn2(+)-dependent, Mg2(+)-dependent and acidic endogenous DNAses on distribution of DNA in fractions differing in tightness of association with the nuclear matrix has been investigated. In the intact cell nuclei all types of DNA-protein bonds were obscured by a tight bonding of DNA with the proteins of replicative complex. Activation of endogenous nuclease activities caused detachment of a significant chromatin fraction from the nuclear matrix, fraction of DNA remained attached to the replicative complex, small fraction of DNA was bound to the nuclear matrix with a less tight bond. The endogenous nucleases are supposed to make cuts mainly in distal parts of the chromatin loops and do not affect the replicative complex, where the tight DNA-matrix bond is localized. Single-strand DNA-specific S1-nuclease preferably attacks the latter site.
研究了Ca2+/Mg2(+)-依赖性、Mn2(+)-依赖性、Mg2(+)-依赖性和酸性内源性脱氧核糖核酸酶的激活对与核基质结合紧密程度不同的组分中DNA分布的影响。在完整细胞核中，所有类型的DNA-蛋白质键都被DNA与复制复合物蛋白质的紧密结合所掩盖。内源性核酸酶活性的激活导致大量染色质组分从核基质上脱离，一部分DNA仍附着于复制复合物，一小部分DNA以较松散的键与核基质结合。推测内源性核酸酶主要在染色质环的远端部分进行切割，而不影响紧密的DNA-基质键所在的复制复合物。单链DNA特异性S1-核酸酶优先攻击后一个位点。
