Goldstone S D, Milligan A D, Hunt N H
Department of Pathology, University of Sydney, Australia.
Biochim Biophys Acta. 1996 Nov 8;1314(1-2):175-82. doi: 10.1016/s0167-4889(96)00082-1.
We previously have demonstrated an obligatory requirement for intracellular reactive oxygen species (ROS) generation during T lymphocyte activation, and have proposed that ROS may act as signalling agents in the regulation of certain cellular processes, for example, during cell cycle entry. In order to test this hypothesis, we have been interested to determine which, if any, cell cycle entry events are affected by oxidative signalling. Given the requirement for both oxidative signalling and altered gene expression during the G0 to G1 phase transition, we have attempted to establish the extent to which oxidative signalling affects global gene expression patterns during cell cycle entry, and to isolate and characterize mRNAs whose expression patterns are responsive to oxidative signalling during this process. Using differential display in a phenotypic screening approach, we have identified 10 mRNA species whose expression patterns were altered in response to inhibition of oxidative signalling during cell cycle entry. The expression patterns of 4 of these 10 mRNAs were unaffected during cell cycle arrest caused by a different mechanism, cyclosporin A-induced interference with calcineurin-mediated signalling events, implying that the altered expression patterns seen were not simply a consequence of cell cycle arrest. This suggests that the expression of these 4 mRNAs is regulated by a mechanism both necessary for cell cycle entry and sensitive to oxidative signalling. RNAse protection assays confirmed that 2 of these 4 mRNAs were indeed responsive to redox regulation. These observations strongly suggest an involvement for oxidative signalling in the regulation of gene expression during the G0 to G1 phase transition, in peripheral blood mononuclear cells at least.
我们之前已经证明，T淋巴细胞激活过程中细胞内活性氧（ROS）的产生是必不可少的，并且提出ROS可能作为信号分子参与某些细胞过程的调控，例如在细胞进入细胞周期时。为了验证这一假设，我们一直致力于确定在细胞进入细胞周期时，氧化信号是否会影响细胞周期进入的某些事件，如果有的话。鉴于在G0到G1期转变过程中对氧化信号和基因表达改变的需求，我们试图确定氧化信号在细胞进入细胞周期时对整体基因表达模式的影响程度，并分离和鉴定在此过程中其表达模式对氧化信号有反应的mRNA。通过在表型筛选方法中使用差异显示，我们鉴定出10种mRNA，其表达模式在细胞进入细胞周期时因氧化信号的抑制而发生改变。在由不同机制即环孢素A诱导的对钙调神经磷酸酶介导的信号事件的干扰导致的细胞周期停滞期间，这10种mRNA中的4种的表达模式未受影响，这意味着所观察到的表达模式改变不仅仅是细胞周期停滞的结果。这表明这4种mRNA的表达受一种对细胞进入细胞周期必不可少且对氧化信号敏感的机制调控。核糖核酸酶保护试验证实，这4种mRNA中的2种确实对氧化还原调节有反应。这些观察结果强烈表明，至少在外周血单核细胞中，氧化信号参与了G0到G1期转变过程中的基因表达调控。
