Ottawa Institute of Systems Biology, University of Ottawa, Canada.
Department of Biology, Carleton University, Ottawa, Canada.
FEBS J. 2024 Oct;291(20):4602-4618. doi: 10.1111/febs.17243. Epub 2024 Aug 5.
Maintaining cellular homeostasis in the face of stress conditions is vital for the overall well-being of an organism. Reactive oxygen species (ROS) are among the most potent cellular stressors and can disrupt the internal redox balance, giving rise to oxidative stress. Elevated levels of ROS can severely affect biomolecules and have been associated with a range of pathophysiological conditions. In response to oxidative stress, yeast activator protein-1 (Yap1p) undergoes post-translation modification that results in its nuclear accumulation. YAP1 has a key role in oxidative detoxification by promoting transcription of numerous antioxidant genes. In this study, we identified previously undescribed functions for NCE102, CDA2, and BCS1 in YAP1 expression in response to oxidative stress induced by hydrogen peroxide (HO). Deletion mutant strains for these candidates demonstrated increased sensitivity to HO. Our follow-up investigation linked the activity of these genes to YAP1 expression at the level of translation. Under oxidative stress, global cap-dependent translation is inhibited, prompting stress-responsive genes like YAP1 to employ alternative modes of translation. We provide evidence that NCE102, CDA2, and BCS1 contribute to cap-independent translation of YAP1 under oxidative stress.
在面对应激条件时,维持细胞内稳态对于生物体的整体健康至关重要。活性氧(ROS)是最有效的细胞应激源之一,可破坏内部氧化还原平衡,引发氧化应激。ROS 水平升高会严重影响生物分子,并与多种病理生理状况有关。在氧化应激下,酵母激活蛋白 1(Yap1p)发生翻译后修饰,导致其在核内积累。YAP1 通过促进许多抗氧化基因的转录,在氧化解毒中发挥关键作用。在这项研究中,我们发现了 NCE102、CDA2 和 BCS1 在过氧化氢(HO)诱导的氧化应激下 YAP1 表达中的以前未描述的功能。这些候选基因的缺失突变菌株对 HO 的敏感性增加。我们的后续研究将这些基因的活性与翻译水平上的 YAP1 表达联系起来。在氧化应激下,全局帽依赖性翻译被抑制,促使 YAP1 等应激响应基因采用替代的翻译模式。我们提供的证据表明,NCE102、CDA2 和 BCS1 有助于氧化应激下 YAP1 的无帽依赖性翻译。