Okita T W, Volcani B E
Biochim Biophys Acta. 1978 Jun 22;519(1):76-86. doi: 10.1016/0005-2787(78)90063-1.
During recovery from silicate-starvation, a period of active DNA synthesis, synchronized cells of Cylindrotheca fusiformis incorporated 3 times more L-[U-14C]aspartate than did starved cells. Of the diatoms's four DNA polymerases, A and D are synthesized during silicate recovery, indicating that they are involved in silicate-dependent DNA replication. Polymerase B, and the chloroplast enzyme, polymerase C, are synthesized during silicate-starvation and their levels are unaffected by the addition of silicate. DEAE-Sephadex analysis of the DNA-binding proteins, labeled with [14C]- and [3H]asparate, shows that only three proteins are synthesized in cells recovering from silicate-starvation. Two of these proteins correspond to polymerases A and D, while the function of the third protein is not known. At least 15 other proteins are present in silicate-starved cells and their synthesis is repressed upon the addition of silicate. Models are proposed which describe the modes by which silicate might regulate DNA synthesis in the diatom.
在从硅酸盐饥饿状态恢复的过程中，这是一个活跃的DNA合成期，梭形筒柱藻的同步细胞掺入的L-[U-¹⁴C]天冬氨酸比饥饿细胞多3倍。在硅藻的四种DNA聚合酶中，A和D在硅酸盐恢复期间合成，这表明它们参与了依赖硅酸盐的DNA复制。聚合酶B以及叶绿体酶聚合酶C在硅酸盐饥饿期间合成，并且它们的水平不受添加硅酸盐的影响。用[¹⁴C] - 和[³H]天冬氨酸标记的DNA结合蛋白的DEAE-葡聚糖分析表明，在从硅酸盐饥饿状态恢复的细胞中仅合成三种蛋白质。其中两种蛋白质对应于聚合酶A和D，而第三种蛋白质的功能尚不清楚。在硅酸盐饥饿的细胞中至少存在15种其他蛋白质，并且在添加硅酸盐后它们的合成受到抑制。提出了描述硅酸盐可能调节硅藻中DNA合成方式的模型。
