Stott D I, Williamson A R
Biochim Biophys Acta. 1978 Dec 21;521(2):726-38. doi: 10.1016/0005-2787(78)90312-x.
The synthesis of non-histone chromatin proteins and nucleoplasmic proteins has been followed during lipopolysaccharide-induced division and differentiation of murine B lymphocytes. Synthesis was measured by pulse labelling with [3H]leucine, extraction of proteins was under conditions designed to prevent proteolysis and analysis of labelled proteins was by polyacrylamide gel electrophoresis. The average specific activity of non-histone chromatin proteins increased 3-fold, to a maximum, after culture for 24 h with lipopolysaccharide. Comparison of the relative synthesis of individual proteins (stimulation index) reveals three distinct responses: (1) those in the largest group show low stimulation indices, generally less than two; (2) a group of four proteins have indices between 4 and 5; (3) two proteins (molecular weights 21 000 and 22 000) both show an index of 5 at 24 h rising to between 7 and 8 by 48 h when the average specific activity is falling, coinciding with the period of rapid differentiation to high rate IgM secretion. Additionaly at this time, a newly labelled protein (Mr = 36 500) appears in the nucleoplasm followed by a second protein (Mr = 63 000) appearing between 48 and 72 h. The patterns of change are consistent with an overall increase in non-histone chromatin proteins synthesis, necessary for cell division, with superimposed specific changes in synthesis of non-histone chromatin proteins which could be related to regulation of cell differentiation.
在脂多糖诱导小鼠B淋巴细胞分裂和分化的过程中，对非组蛋白染色质蛋白和核质蛋白的合成进行了跟踪研究。通过用[³H]亮氨酸脉冲标记来测定合成情况，蛋白质提取是在旨在防止蛋白水解的条件下进行的，标记蛋白的分析则通过聚丙烯酰胺凝胶电泳进行。用脂多糖培养24小时后，非组蛋白染色质蛋白的平均比活性增加了3倍，达到最大值。对单个蛋白质相对合成情况（刺激指数）的比较揭示了三种不同的反应：（1）最大的一组蛋白质显示出低刺激指数，通常小于2；（2）一组四种蛋白质的指数在4到5之间；（3）两种蛋白质（分子量分别为21000和22000）在24小时时刺激指数均为5，到48小时时升至7到8之间，此时平均比活性在下降，这与快速分化为高分泌率IgM的时期相吻合。此外，此时一种新标记的蛋白质（Mr = 36500）出现在核质中，随后第二种蛋白质（Mr = 63000）在48到72小时之间出现。这些变化模式与细胞分裂所必需的非组蛋白染色质蛋白合成的总体增加相一致，同时伴随着非组蛋白染色质蛋白合成的特定变化，这些变化可能与细胞分化的调节有关。
