Identification of thioredoxin targets in guard cell enriched epidermal peels using cysTMT proteomics

Abstract

Redox homeostasis is tightly regulated for proper cellular activities. Specific protein-protein interactions between redox active molecules such as thioredoxin (Trx) and target proteins constitute the basis for redox-regulated biological processes. The use of cysTMT quantitative proteomics for studying Trx reactions enabled identification of potential Trx targets that provide important insights into the redox regulation in guard cells, a specialized plant cell type responsible for sensing of environmental signals, gas exchange and plant productivity.

Bicarbonate Induced Redox Proteome Changes in Arabidopsis Suspension Cells

“…In addition, a ferredoxin-dependent nitrite reductase (NR) was found to be oxidized at 30 min elevated /CO 2 treatment (Table 1 ). Similar result was also found in Brassica napus guard cells (Zhang et al, 2016 ). NR is present in photosynthetic tissues and cells (Hirasawa et al, 2010 ).…”

“…Notably, ASA1 functions in abscisic acid (ABA) mediated drought response, and overexpression of ASA1 reduced water loss in Arabidopsis (Yao et al, 2012 ). It is not known whether ASA1 is redox regulated in ABA signaling as some protein kinases (Zhu et al, 2014 ; Zhang et al, 2016 ).…”

Characterization of thiol‐based redox modifications of Brassica napusSNF1‐related protein kinase 2.6‐2C

“…MS‐based proteomics approaches have been used to identify redox‐regulated thiol modifications with different cysteine‐tagging techniques such as isotope‐coded affinity tagging (ICAT) , cysteine reactive tandem mass tagging (cysTMT) , and iodoacetyl tandem mass tagging (iodoTMT) . In spite of the rapid progress in discovering proteins with specific redox PTMs in response to biotic or abiotic stresses , only limited studies have characterized the biological functions of the redox PTMs .…”

Protein Promiscuity in H2O2Signaling

“…For proteomic characterization of reversible disulfides with physiological significance, thioredoxin (Trx) has recently been utilized as a tool for specific capture of cellular redox targets (8,206,254,278,283,421). Both the tandem mass tag (TMT) and ICAT proteomic methods have been adapted to identify Trx targets, merely by using Trx as the postalkylation reductant instead of a chemical reducing agent, such as DTT or tris(2-carboxyethyl)phosphine (TCEP) (278,421). Other in vivo approaches involve replacement of endogenous Trx with a resolving cysteine mutant of Trx, which forms a stable mixed disulfide with oxidized cysteines of the target proteins.…”