CHROMATIN STRUCTURE AND THE CELL DIVISION CYCLE
CHROMATIN STRUCTURE AND THE CELL DIVISION CYCLE
复制标题
染色质结构和细胞分裂周期
作者：
T. Pederson;E. Robbins
同步培养的HeLa细胞中放线菌素-~3H结合量的测定表明，尽管细胞核DNA含量增加了一倍，但染色质的结合量在S期逐渐降低，在G2期和有丝分裂期达到最低水平，然后在随后的G1期逐渐增加。由于这种模式在活细胞、乙醇固定的细胞和分离的细胞核中很明显，但在纯化的DNA中不明显，放线菌素结合谱可能反映了细胞周期不同阶段DNA和染色体蛋白之间结合程度的变化。
Measurements of actinomycin-3H binding in synchronized HeLa cells reveal that the binding capacity of chromatin decreases progressively during the S phase despite a doubling of nuclear DNA content, reaches a minimal level during G2 and mitosis, and then increases gradually throughout the subsequent G1 interval. Since this pattern was evident in experiments with living cells, ethanol-fixed cells, and isolated nuclei, but not with purified DNA, the actinomycin binding profile may reflect changes in the degree of association between DNA and chromosomal proteins at different stages of the cell cycle.