Wilson R E, Sutherland R M
Department of Biophysics, University of Rochester, NY 14642.
Int J Radiat Oncol Biol Phys. 1989 Apr;16(4):957-61. doi: 10.1016/0360-3016(89)90895-x.
When Chinese Hamster ovary cells were exposed to severe hypoxia they responded with an enhanced synthesis rate of a small group of specific proteins, which we have termed the oxygen regulated proteins (ORPs). The five major ORPs had molecular weights of 33, 80, 100, 150, and 260 kD. ORP260 was the first ORP to be synthesized at enhanced rates after the induction of hypoxia, reaching its maximal synthesis rate after only a few hours. The other ORPs responded slower, but were being synthesized at maximal rates by 8 hr of hypoxia. Upon reoxygenation, the synthesis rates of the ORPs declined rapidly with ORP260 again responding most rapidly. They all reached control levels by 12 hr of recovery. The induction of enhanced synthesis of these proteins required a very severe degree of hypoxia. They were not seen at oxygen levels higher than 0.03%. While enhanced synthesis of the ORPs was turned on and off quickly with induction of, and recovery from hypoxia, the proteins were not degraded at high rates once synthesized. All five major ORPs have apparent half-lives in excess of 24 hr. When cells were exposed to hypoxia for 20 hr and then allowed to recover for 15 hr, a population of cells was generated that had, on average, at least twice the cell volume as aerobic control cells. These large cells also contained greater than 4C DNA content as well as enhanced amounts of RNA.
当中国仓鼠卵巢细胞暴露于严重缺氧环境时，它们会以增强一小群特定蛋白质的合成速率做出反应，我们将这些蛋白质称为氧调节蛋白（ORP）。这五种主要的ORP分子量分别为33、80、100、150和260 kD。ORP260是缺氧诱导后第一个以增强速率合成的ORP，仅在数小时后就达到其最大合成速率。其他ORP反应较慢，但在缺氧8小时时以最大速率合成。复氧后，ORP的合成速率迅速下降，其中ORP260再次反应最为迅速。到恢复12小时时，它们都达到了对照水平。这些蛋白质合成增强的诱导需要非常严重程度的缺氧。在高于0.03%的氧水平下未观察到它们。虽然随着缺氧的诱导和恢复，ORP的合成增强迅速开启和关闭，但这些蛋白质一旦合成，并不会以高速率降解。所有五种主要的ORP的表观半衰期都超过24小时。当细胞暴露于缺氧环境20小时，然后恢复15小时时，产生了一群细胞，其平均细胞体积至少是需氧对照细胞的两倍。这些大细胞还含有大于4C的DNA含量以及增加的RNA量。
