Duda C T, Cherry J H
Horticulture Department, Purdue University, Lafayette, Indiana 47907.
Plant Physiol. 1971 Feb;47(2):262-8. doi: 10.1104/pp.47.2.262.
The synthesis of RNA by chromatin-bound RNA polymerase prepared from sugar beet (Beta vulgaris) root tissue is completely dependent on the presence of a divalent metal (Mg(2+) or Mn(2+)) and the presence of four ribonucleoside triphosphates. Accumulation of labeled acid-insoluble product is inhibited by the addition of RNase and actinomycin D to the reaction. When beet root slices are washed for 25 hours, chromatin-associated RNA polymerase activity increases 7-fold over that of unwashed tissue. This enzyme activity declines with further washing. DNA template availability, as measured by saturating levels of added Escherichia coli RNA polymerase, was also found to follow a pattern similar to that for RNA polymerase. Nearest neighbor frequencies of the RNA synthesized by chromatin isolated from unwashed and washed tissue are different.Washing tissue in solutions of gibberellic acid and auxin enhances template availability of the isolated chromatin. Experiments with isolated nuclei indicate an effect of these hormones on RNA synthesis.
从甜菜（Beta vulgaris）根组织制备的与染色质结合的RNA聚合酶合成RNA完全依赖于二价金属（Mg(2+)或Mn(2+)）的存在以及四种核糖核苷三磷酸的存在。向反应中添加RNase和放线菌素D可抑制标记的酸不溶性产物的积累。当甜菜根切片洗涤25小时后，与染色质相关的RNA聚合酶活性比未洗涤的组织增加7倍。随着进一步洗涤，这种酶活性下降。通过添加饱和水平的大肠杆菌RNA聚合酶来测量的DNA模板可用性也发现遵循与RNA聚合酶相似的模式。从未洗涤和洗涤过的组织中分离的染色质合成的RNA的最近邻频率不同。在赤霉素和生长素溶液中洗涤组织可提高分离染色质的模板可用性。对分离细胞核的实验表明这些激素对RNA合成有影响。
