Paponov V D, Sigora G A, Rad'ko S P
Biull Eksp Biol Med. 1987 Nov;104(11):557-9.
The structural heterogeneity of calf thymus chromatin preparations was studied at the level of DNA topology by analysing the influence of ethidium bromide on the chromatin viscosity in deproteinizing medium. In 0.7 M NaCl the chromatin was separated into the fractions with linear DNA (3--36% in various preparations) and with supercoiled circular DNA (scc DNA), which differ from each other in their adhesive properties. Reduction of disulfide bonds in residual chromatin protein with 5% mercaptoethanol linearized scc DNA, present in chromatin preparations as nuclear matrix subunits containing some loops of scc DNA on the protein globule.
通过分析溴化乙锭对脱蛋白介质中染色质粘度的影响，在DNA拓扑结构水平上研究了小牛胸腺染色质制剂的结构异质性。在0.7M NaCl中，染色质被分离成具有线性DNA的组分（在各种制剂中占3%-36%）和具有超螺旋环状DNA（scc DNA）的组分，它们在粘附特性上彼此不同。用5%巯基乙醇还原残留染色质蛋白中的二硫键可使scc DNA线性化，scc DNA以核基质亚基的形式存在于染色质制剂中，在蛋白质球上含有一些scc DNA环。
