Reactive oxygen species, ROS, are acknowledged signaling molecules in cellular processes. Singlet molecular oxygen, O₂(a¹Δ_g), is one ROS that can initiate cell responses that range from death to proliferation. To better understand the mechanisms involved, it is necessary to further investigate cell response to the “dose” of O₂(a¹Δ_g) that has been selectively produced at the expense of other ROS. In this context, dose refers not just to the amount of O₂(a¹Δ_g) produced, but also to the subcellular spatial domain in which it is produced. In this study, we selectively produced small and non-toxic amounts of O₂(a¹Δ_g) in sensitizer-free experiments by irradiating oxygen at 765 nm using a laser focused either into the nucleus or cytoplasm of HeLa cells. We find that O₂(a¹Δ_g)-mediated cell proliferation depends appreciably on the site of O₂(a¹Δ_g) production. At the same incident laser power, irradiation into the cytoplasm elicits moderate enhancement of proliferation, whereas irradiation into the nucleus leads to an appreciable delay in the onset and completion of mitosis. We discuss these results in light of what is known about the intracellular photophysics of O₂(a¹Δ_g) and the redox state of different cell domains.

中文翻译：

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通过直接765 nm辐射 通过亚细胞在空间上分解产生单线态氧的细胞周期调控：操纵有丝分裂的发作

活性氧，ROS，是细胞过程中公认的信号分子。单线态分子氧，O- ₂（A ¹ Δ_克），是一种可以发起，范围从死亡到增殖细胞应答一个ROS。为了更好地理解所涉及的机制，有必要进一步调查到的“剂量”细胞应答Ô ₂（A ¹ Δ_克），其具有在其他ROS为代价被选择性地生产。在这种情况下，剂量是指不只是量Ô ₂（A ¹ Δ_克）产生的，而且要在其生产的亚细胞空间域。在这项研究中，我们选择性地生产了少量无毒的O₂（A ^1个Δ_克）在通过在使用激光765纳米照射无氧敏化剂实验集中任一入HeLa细胞的细胞核或细胞质中。我们发现，Ô ₂（A ¹ Δ_克）介导的细胞增殖显着地取决于的O在网站上₂（A ¹ Δ_克）的生产。在相同的入射激光功率下，照射到细胞质中会引起增殖的适度增强，而照射到细胞核中则会导致有丝分裂的发生和完成的明显延迟。我们讨论这些结果的所谓关于澳胞内光物理光₂（一个^1个Δ_g）和不同细胞域的氧化还原状态。