Stott D I
Biochim Biophys Acta. 1980 Dec 11;610(2):371-83. doi: 10.1016/0005-2787(80)90018-0.
Nuclear and cytoplasmic proteins synthesised by mouse lymphocytes stimulated in vitro by the B lymphocyte mitogen, lipopolysaccharide, have been analysed by one- and two-dimensional polyacrylamide gel electrophoresis at early and later times after the onset of stimulation. During the first 4 h no change was observed in the electrophoretic profiles but differences in turnover of various nuclear proteins within the same sample were noted. This is contrasted with the previous observations that phosphorylation of nuclear proteins is stimulated within 2 h. (Stott, D.I. and Williamson, A.R. (1978) Biochim. Biophys. Acta 521, 739-752). During prolonged culture, synthesis of nucleoplasmic proteins declined between day 2 and day 3, being reduced to undetectable levels at the end of the 3-day culture period. In contrast, synthesis of many non-histone chromatin proteins was stimulated between 24 and 48 h, the time course and degree of stimulation varying between different proteins. Certain proteins appeared to be synthesized de novo. These events occur at a time of rapidly increasing IgM synthesis and cell differentiation. It is suggested that an initial step in B lymphocyte triggering may involve phosphorylation of preexisting nuclear proteins leading to gene activation followed by synthesis and phosphorylation of new gene regulatory molecules.
用B淋巴细胞促分裂原脂多糖在体外刺激小鼠淋巴细胞后，所合成的核蛋白和胞质蛋白，已在刺激开始后的早期和晚期通过一维及二维聚丙烯酰胺凝胶电泳进行了分析。在最初4小时内，电泳图谱未观察到变化，但注意到同一样品中各种核蛋白的周转率存在差异。这与之前观察到的核蛋白在2小时内被刺激磷酸化形成对比。（斯托特，D.I.和威廉姆森，A.R.（1978年）《生物化学与生物物理学学报》521卷，739 - 752页）。在延长培养期间，核质蛋白的合成在第2天至第3天之间下降，在3天培养期结束时降至检测不到的水平。相比之下，许多非组蛋白染色质蛋白的合成在24至48小时之间受到刺激，不同蛋白的刺激时间进程和程度有所不同。某些蛋白似乎是重新合成的。这些事件发生在IgM合成和细胞分化迅速增加的时期。有人提出，B淋巴细胞触发的初始步骤可能涉及预先存在的核蛋白磷酸化，导致基因激活，随后是新的基因调节分子的合成和磷酸化。
