Gerner E W, Meyn R E, Humphrey R M
J Cell Physiol. 1976 Mar;87(3):277-87. doi: 10.1002/jcp.1040870303.
The kinetics of non-histone chromosomal protein (NHCP) synthesis were studied in Chinese hamster ovary (CHO) plateau phase cells stimulated to proliferate and were compared to NHCP synthesis kinetics in two populations of synchronous G1 traversing cells. In all cases, NHCP synthesis rates increase 3- to 5-fold as cells traversed G1 and attained maximum values one hour before semi-conservative DNA replication began. Similar to results in synchronous G1 cells, the molecular weight distributions of the NHCP fraction from stimulated plateau phase cells underwent only minor changes, measured by sodium dodecylsulfate (SDS) polyacrylamide gel electrophoresis, as these cells moved toward S phase. Yet, during this progression after plateau phase and in the transition from early G1 to late G1 in synchronous cells, the total NHCP fraction increased significantly (1.5-2-fold) in amount per cell. These data indicate that plateau phase cells are similar to early G1 cells both in terms of their amounts of non-histone per cell and in their subsequent NHCP synthesis kinetics as they move toward S phase. These results extend previous findings which suggested that NHCP synthesis was coupled to DNA replication and demonstrate that the increased NHCP synthesis and accumulation in chromatin may be a biochemical marker for G1 progression.
对中国仓鼠卵巢（CHO）平台期细胞在被刺激增殖时非组蛋白染色体蛋白（NHCP）合成的动力学进行了研究，并与两个同步进入G1期细胞群体中NHCP合成动力学进行了比较。在所有情况下，当细胞穿越G1期时，NHCP合成速率增加3至5倍，并在半保留DNA复制开始前一小时达到最大值。与同步G1期细胞的结果相似，通过十二烷基硫酸钠（SDS）聚丙烯酰胺凝胶电泳测量，来自受刺激平台期细胞的NHCP组分的分子量分布在这些细胞向S期移动时仅发生微小变化。然而，在平台期后的这一进程中以及同步细胞从早期G1向晚期G1转变期间，每个细胞中NHCP的总量显著增加（1.5至2倍）。这些数据表明，平台期细胞在每个细胞的非组蛋白量及其向S期移动时随后的NHCP合成动力学方面与早期G1期细胞相似。这些结果扩展了先前的研究发现，即NHCP合成与DNA复制相关，并证明染色质中NHCP合成和积累的增加可能是G1期进程的生化标志物。
