Cysteine homeostasis plays an essential role in plant immunity

Abstract

Summary• Cysteine is the metabolic precursor of essential biomolecules such as vitamins, cofactors, antioxidants and many defense compounds. The last step of cysteine metabolism is catalysed by O-acetylserine(thiol)lyase (OASTL), which incorporates reduced sulfur into O-acetylserine to produce cysteine. In Arabidopsis thaliana, the main OASTL isoform OAS-A1 and the cytosolic desulfhydrase DES1, which degrades cysteine, contribute to the cytosolic cysteine homeostasis.• Meta-analysis of the transcriptomes of knockout plants for OAS-A1 and for DES1 show a high correlation with the biotic stress series in both cases.• The study of the response of knockout mutants to plant pathogens shows that des1 mutants behave as constitutive systemic acquired resistance mutants, with high resistance to biotrophic and necrotrophic pathogens, salicylic acid accumulation and WRKY54 and PR1 induction, while oas-a1 knockout mutants are more sensitive to biotrophic and necrotrophic pathogens. However, oas-a1 knockout mutants lack the hypersensitive response associated with the effector-triggered immunity elicited by Pseudomonas syringae pv. tomato DC3000 avrRpm1.• Our results highlight the role of cysteine as a crucial metabolite in the plant immune response.

S-Sulfhydration: A Cysteine Posttranslational Modification in Plant Systems

“…O-acetyl-Ser (thiol)lyase A1, which incorporates sulfide to form Cys, and DES1. Therefore, the level of sulfide may change under the developmental and stress conditions that may regulate these activities (Alvarez et al, 2011;Álvarez et al, 2012a;Laureano-Marín et al, 2014).…”

Hydrogen Sulfide Regulates the Cytosolic/Nuclear Partitioning of Glyceraldehyde-3-Phosphate Dehydrogenase by Enhancing its Nuclear Localization

“…Detailed characterization of DES1-deficient mutants (des1) revealed its function in the generation of sulfide in the cytosol for signaling (Romero et al 2013, Romero et al 2014. Thus, DES1 mutation reduces the total leaf endogenous H 2 S concentration and affects important plant processes, such as plant responses to abiotic stress conditions, plant immunity, regulation of leaf senescence, progress of autophagy and modulation of ABA-dependent stomatal closure , Alvarez et al 2012a, Alvarez et al 2012b, Scuffi et al 2014, LaureanoMarin et al 2016.…”

Application of Cysteine, Methionine and Amino Acid Containing Fertilizers to Replace Urea: The Effects on Yield and Quality of Broccoli

“…In addition to its structural role in proteins, cysteine functions as a precursor for essential biomolecules, such as vitamins and cofactors antioxidants, such as glutathione and many defense compounds, such as glucosinolates, thionins or phytoalexins. Cysteine is synthesized in plants in the cytosol, plastids and mitochondria by the sequential action of the enzymes serine acetyltransferase which synthesizes the intermediary product O-acetylserine (OAS), and O-acetylserine(thiol)lyase which combines a sulfide molecule with an OAS molecule to produce cysteine [5].…”