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bioRxiv · 10.1101/2024.12.16.626735

Data-independent acquisition (DIA)-based Label-free Redox Proteomics (DIALRP) Reveals Novel Oxidative Stress Responsive Translation Factors

Kobayashi, D.·Takami, T.·Matsumoto, M.
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Abstract

Oxidative stress is a key factor in numerous physiological and pathological processes, including aging, cancer, and neurodegenerative diseases. Protein cysteine residues are particularly susceptible to oxidative stress-induced modifications that can alter their structure and function, thereby affecting intracellular signaling pathways. In this study, we developed a data-independent acquisition mass spectrometry (DIA-MS)-based label-free redox proteomics method, termed DIALRP, to comprehensively analyse cysteine oxidative modifications in the prostate cancer cell line DU145 under oxidative stress induced by menadione (MND). Through these analyses, we identified translation-related factors with significantly elevated cysteine oxidation upon MND treatment and evaluated their functional relevance. Notably, our data demonstrated that the inhibition of EIF2, EIF6, and EEF2 complex formation due to oxidative stress occurs during the cellular response to translational inhibition. These insights reveal a previously unrecognized mechanism of translation regulation under oxidative stress and provide a valuable framework for future studies on redox-mediated cellular processes.

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Kobayashi, D., Takami, T., Matsumoto, M.. 2024-12-16. Data-independent acquisition (DIA)-based Label-free Redox Proteomics (DIALRP) Reveals Novel Oxidative Stress Responsive Translation Factors. https://doi.org/10.1101/2024.12.16.626735

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