Arabidopsis thaliana GLUTATHIONE‐S‐TRANSFERASE THETA 2 interacts with RSI1/FLD to activate systemic acquired resistance

Abstract

A partly infected plant develops systemic acquired resistance (SAR) and shows heightened resistance during subsequent infections. The infected parts generate certain mobile signals that travel to the distal tissues and help to activate SAR. SAR is associated with epigenetic modifications of several defence-related genes. However, the mechanisms by which mobile signals contribute to epigenetic changes are little known. Previously, we have shown that the Arabidopsis REDUCED SYSTEMIC IMMUNITY 1 (RSI1, alias FLOWERING LOCUS D; FLD), which codes for a putative histone demethylase, is required for the activation of SAR. Here, we report the identification of GLUTATHIONE-S-TRANSFERASE THETA 2 (GSTT2) as an interacting factor of FLD. GSTT2 expression increases in pathogen-inoculated as well as pathogen-free distal tissues. The loss-of-function mutant of GSTT2 is compromised for SAR, but activates normal local resistance. Complementation lines of GSTT2 support its role in SAR activation. The distal tissues of gstt2 mutant plants accumulate significantly less salicylic acid (SA) and express a reduced level of the SA biosynthetic gene PAL1. In agreement with the established histone modification activity of FLD, gstt2 mutant plants accumulate an enhanced level of methylated and acetylated histones in the promoters of WRKY6 and WRKY29 genes. Together, these results demonstrate that GSTT2 is an interactor of FLD, which is required for SAR and SAR-associated epigenetic modifications.

Comparative proteomics of three Chinese potato cultivars to improve understanding of potato molecular response to late blight disease

“…They include four peroxidases; (M1B7J5, M1B3Q2, M1CCK0, and M1CCJ9), a chloroplast lipocalin protein (Q38JB4), a probable glutathione S-transferase (P32111/GSTs), osmotin-like protein (Q84U63), thaumatin-like protein (Q5XUG9), and pathogenesis-related protein 10 (Q8LRU6/PR-10). GSTs have an antioxidative effect against oxidative stress [ 60 ] and the abundance of the protein was confirmed by western blot. The osmotin and thaumatin produce antifungal activity [ 61 ], and PR proteins are highly induced during microbial infection and wounding [ 62 ].…”

Functional, Structural and Biochemical Features of Plant Serinyl-Glutathione Transferases

“…No more physiological information is available for other Ser-GST classes, namely GSTT, GSTZ, and TCHQD (3, 2, and 1 members in A. thaliana , respectively). A. thaliana GSTT2 seems involved in the modulation of systemic acquired resistance by altering the expression of key genes involved in this process through epigenetic modifications (Banday and Nandi, 2018). According to its capacity to catalyze the isomerisation of maleylacetoacetate into fumarylacetoacetate in vitro , AtGSTZ1 is likely involved in tyrosine catabolism, as demonstrated in animals (Edwards and Dixon, 2000).…”

Genome-wide identification and expression profiling of glutathione transferase gene family under multiple stresses and hormone treatments in wheat (Triticum aestivum L.)

“…AtGSTZ1 displayed isomerase activity for maleylacetone and a putative role in tyrosine catabolism [41]. AtGSTT2 could activate systemic acquired resistance (SAR) by interacting with RSI1/FLD [42].…”