Mendelsohn J, Fox R M, Goulian M, Barbosa E
Immunol Commun. 1975;4(4):373-85. doi: 10.3109/08820137509055787.
DNA synthesis was studied in human peripheral blood lymphocytes that had been stimulated with phytohemagglutinin. DNA pulse-labeled with [3H]thymidine was fractionated by sucrose gradient centrifugation or by chromatography on hydroxylapatite columns. Nascent DNA was identified as a single-stranded species that sedimented at 4-5S in neutral sucrose gradients and appeared to be precursor to chromosomal DNA in pulse-chase experiments. At least two-thirds of the nascent DNA was released as single strands from high molecular weight DNA without employing a denaturation step. It is concluded that synthesis of DNA by phytohemagglutinin-stimulated lymphocytes involves a low molecular weight, single-stranded, short-lived intermediate similar to that described for other eukaryotic cells.
对用植物血凝素刺激的人外周血淋巴细胞中的DNA合成进行了研究。用[3H]胸腺嘧啶核苷进行脉冲标记的DNA通过蔗糖梯度离心或在羟基磷灰石柱上进行色谱分离。新生DNA被鉴定为在中性蔗糖梯度中沉降系数为4-5S的单链物质，并且在脉冲追踪实验中似乎是染色体DNA的前体。在不进行变性步骤的情况下，至少三分之二的新生DNA以单链形式从高分子量DNA中释放出来。得出的结论是，植物血凝素刺激的淋巴细胞合成DNA涉及一种低分子量、单链、寿命短暂的中间体，类似于其他真核细胞中所描述的中间体。
