Horticulture Department, Purdue University, Lafayette, Indiana 47907.
Plant Physiol. 1971 Jun;47(6):771-4. doi: 10.1104/pp.47.6.771.
Chromatin-associated RNA polymerase activity increases during washing of sugar beet tissue to a maximum by 20 hours. This increase was inhibited by dosages of gamma irradiation between 50 and 400 krad. Template availability, as measured by saturating levels of added Escherichia coli RNA polymerase, also increased with washing and was inhibited, although to a lesser extent, by the above irradiation dosages. Neither endogenous polymerase activity nor template availability was affected by high dosages (300 krad) in unwashed tissue. Exposure of tissue to irradiation (300 krad) at different times during a 20-hour washing period severely inhibited the development of RNA polymerase activity during the early stages of washing. The inhibition of template availability, however, was independent of time of irradiation. The data presented are discussed in relation to the mechanisms involved in the inhibitory effects of gamma irradiation on RNA production and subsequent protein synthesis.
在对甜菜组织进行洗涤的过程中，染色质相关 RNA 聚合酶的活性会增加，在 20 小时时达到最大值。这种增加会被 50 至 400 拉德剂量的γ射线辐射抑制。模板的可用性，即通过添加的大肠杆菌 RNA 聚合酶的饱和水平来衡量，也会随着洗涤而增加，尽管受上述辐射剂量的抑制程度较小。未洗涤组织中的高剂量（300 拉德）既不会影响内源性聚合酶活性，也不会影响模板可用性。在 20 小时洗涤期的不同时间向组织暴露于辐射（300 拉德）会严重抑制洗涤早期 RNA 聚合酶活性的发展。然而，模板可用性的抑制与辐射时间无关。所提出的数据与涉及γ射线辐射对 RNA 产生和随后的蛋白质合成的抑制作用的机制有关。
