Abstract
The generation of reactive oxygen species (ROS) is inevitably linked to life. However, the precise role of ROS in signalling and specific targets is largely unknown. We perform a global proteomic analysis to delineate the yeast redoxome to a depth of more than 4,300 unique cysteine residues in over 2,200 proteins. Mapping of redox-active thiols in proteins exposed to exogenous or endogenous mitochondria-derived oxidative stress reveals ROS-sensitive sites in several components of the translation apparatus. Mitochondria are the major source of cellular ROS. We demonstrate that increased levels of intracellular ROS caused by dysfunctional mitochondria serve as a signal to attenuate global protein synthesis. Hence, we propose a universal mechanism that controls protein synthesis by inducing reversible changes in the translation machinery upon modulating the redox status of proteins involved in translation. This crosstalk between mitochondria and protein synthesis may have an important contribution to pathologies caused by dysfunctional mitochondria.
Highlights
The generation of reactive oxygen species (ROS) is inevitably linked to life
Yeast pellets were homogenised in 10% trichloroacetic acid (TCA) to retain the in vivo thiol oxidation status of proteins, followed by quantitative thiol trapping using cysteine-specific ICAT reagents[5] and stateof-the-art liquid chromatography tandem Mass spectrometry (MS) (LC-MS/MS) (Fig. 1a)
The ICAT-based approach proved to be highly effective as demonstrated by the high number of identified unique cysteine-containing peptide sequences compared with shut-gun proteomic data of the whole yeast proteome[17,18] (Supplementary Fig. 1a)
Summary
The generation of reactive oxygen species (ROS) is inevitably linked to life. the precise role of ROS in signalling and specific targets is largely unknown. The OxICAT technology[5], which combines differential thiol trapping and isotope-coded affinity tagging, allows for the site-specific quantification of the percentage of protein thiol oxidation in vivo This strategy has been applied to different species, showing that cysteine residues in several proteins are partially oxidised under steady-state conditions[6]. Redox-active thiols may become oxidised, reversibly or irreversibly, upon increase of reactive oxygen species (ROS) causing oxidative stress These changes can be deleterious for protein function. Our study identifies a new mechanism that involves redox switches in the translation apparatus and functions to reversibly control protein translation under conditions of increased ROS generation, including mitochondria-derived pathologies
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
