Thiol redox proteomics: Characterization of thiol‐based post‐translational modifications

Abstract

Redox post-translational modifications on cysteine thiols (redox PTMs) have profound effects on protein structure and function, thus enabling regulation of various biological processes. Redox proteomics approaches aim to characterize the landscape of redox PTMs at the systems level. These approaches facilitate studies of condition-specific, dynamic processes implicating redox PTMs and have furthered our understanding of redox signaling and regulation. Mass spectrometry (MS) is a powerful tool for such analyses which has been demonstrated by significant advances in redox proteomics during the last decade. A group of well-established approaches involves the initial blocking of free thiols followed by selective reduction of oxidized PTMs and subsequent enrichment for downstream detection. Alternatively, novel chemoselective probe-based approaches have been developed for various redox PTMs. Direct detection of redox PTMs without any enrichment has also been demonstrated given the sensitivity of contemporary MS instruments. This review discusses the general principles behind different analytical strategies and covers recent advances in redox proteomics. Several applications of redox proteomics are also highlighted to illustrate how large-scale redox proteomics data can lead to novel biological insights.

50 shades of oxidative stress: A state-specific cysteine redox pattern hypothesis

“…When the two inputs oxidised the same peptide, the cysteine redox vector, the magnitude of the observed oxidation, usually differed. Their work and other studies (see Table 2 ) comparing discrete states [ [73] , [74] , [75] , [76] , [77] , [78] , [79] , [80] , [81] ], from rest vs. exercise in humans [ 82 ] to night vs. day in cyanobacteria [ 83 ], support input-specific cysteine redox state outputs.…”

Ten “Cheat Codes” for Measuring Oxidative Stress in Humans

“…Sophisticated MS approaches, such as cysteine-reactive phosphate tag technology (Xiao et al, 2020), can identify and quantify cysteine oxidation with residue-resolution on a proteome-wide scale (Day et al, 2021;Kim et al, 2015;Leichert et al, 2008;Li et al, 2023;Yang et al, 2016). Modern methods allow deep coverage of the cysteine proteome, such as ~34,000 residues across ~9,000 proteins (Xiao et al, 2020).…”