Proteomics profiling reveals the detoxification and tolerance behavior of two bread wheat (Triticum aestivum L.) varieties under arsenate stress

Abstract

Arsenic (As) contaminated irrigation water caused a significant buildup of its level in the agricultural soil and edible tissues of wheat. High levels of As negatively impact grain quality, wheat yield, and human health consequently. It is still unknown how wheat varieties respond to As stress at the proteomic level. Therefore, the present study aimed to deliver mechanistic details regarding the role of proteins in tolerance mechanism against As stress. Two wheat varieties (BARANI-70 and NARC-2009) were exposed to arsenate treatment (200µM) in a hydroponic experiment to evaluate the impacts of arsenic stress using proteomics. Roots of both varieties were used for protein extraction, digestion, and LC-MS/MS analysis to identify differentially abundant proteins (DAPs). Furthermore, various bioinformatic tools were used to study subcellular localization, functional categories, and pathway analysis. The findings identified 67 DAPs in BARANI-70 (up-regulated=56; down-regulated=11) and 89 DAPs in NARC-2009 (up-regulated=34; down-regulated=55). Subcellular localization revealed significant up-regulation of DAPs in mitochondria and chloroplast for BARANI-70 but down-regulation in NARC-2009 under As stress. Functional analysis revealed significant upregulation of DAPs for glutathione, peroxidase, glutathione peroxidase, lactoylglutathione lyase, and glutathione-s-transferase in BARANI-70. Pathway analysis showed regulation of DAPs involved in tetrapyrrole biosynthesis and glycolysis-TCA particularly in BARANI-70 compared to NARC-2009. Furthermore, BARANI-70 showed better growth response under As stress compared to NARC-2009. Thus, better synthesis of stress-responsive DAPs and important pathways in BARANI-70 contributed towards its tolerance against As stress. The present research supports the use of tolerant varieties and identified protein biomarkers to enhance crop resilience against As stress.