Work

Organelle-specific hydrogen sulfide metabolism governs redox homeostasis to regulate plant autophagy and cadmium stress resilience

Year: 2026

Type: article

Abstract: Hydrogen sulfide (H 2 S), traditionally regarded as a toxic threat to the environment and living organisms, is now considered an important gasotransmitter that helps regulate redox balance and autophagy in plants. However, how different sources of H 2 S in certain organelles help control stress responses remains unclear. In our study, how H 2 S is handled in various subcellular compartments of Arabidopsis thaliana was investigated in depth using null mutants defective in H 2 S production ( des1, sir, cas-c1, str1 and str2 ) or consumption ( oas-a1, oas-b and oas-c). Under normal physiological conditions, disruption of H 2 S homeostasis in any cellular compartment altered endogenous H 2 S levels and induced basal autophagy. These findings suggest that maintaining a specific subcellular H 2 S threshold is necessary to control ATG8-dependent autophagic flux. Under cadmium-induced stress, wild-type plants presented coordinated increases in cytosolic OAS-A1 levels, H 2 S accumulation, and protein persulfidation and decreases in sulfenylation and autophagy activation. This redox reprogramming establishes a protective redox control driven by H 2 S, where cadmium-induced H 2 O 2 promotes cysteine sulfenylation followed by persulfidation, thus preventing irreversible overoxidation. Notably, this adaptive redox control was dysregulated in all the organelle-specific mutants, regardless of changes in H 2 S or H 2 O 2 levels, demonstrating that the entire H 2 S network is required for redox protection. Cytosolic and mitochondrial mutants presented the greatest defects in Cd-induced autophagy, indicating that these compartments play a central role in stress-adaptive recycling. • H 2 S signaling in plants exerts distinct effects depending on the subcellular compartment. • Disruption of H 2 S homeostasis triggers basal autophagy. • All compartments are required to activate protein persulfidation under Cd. • Cd-autophagic responses depend on the subcellular location of H 2 S.

Source: Redox Biology

DOI: 10.1016/j.redox.2026.104177

Authors: Reyes Carrillo, Inmaculada Moreno, Angeles Aroca, Cecilia Gotor

Institutions: Consejo Superior de Investigaciones Científicas, Instituto de Bioquímica Vegetal y Fotosíntesis, Universidad de Sevilla

Language: English

Topic: Sulfur Compounds in Biology

Subfield: Biochemistry

Field: Biochemistry, Genetics and Molecular Biology

Domain: Life Sciences

Open Access status: gold

Estimated APC paid: $4,310