The glutathione-dependent alarm triggers signalling responses involved in plant acclimation to cadmium.

This article focuses on the complex plant responses to cadmium (Cd) exposure, emphasizing the central role of glutathione (GSH) depletion and subsequent signaling events in mediating stress acclimation. Cd uptake disrupts cellular redox homeostasis partly through rapid phytochelatin (PC) synthesis, which transiently depletes GSH, triggering ethylene production and organellar stress responses including mitochondrial retrograde regulation (MRR), unfolded protein response (UPR), and autophagy. The review highlights the interplay between these processes and proposes that the gasotransmitter hydrogen sulfide (H2S) fine-tunes acclimation by modulating GSH levels, ethylene signaling, mitochondrial function, and autophagy. It calls for further research into the integrated signaling networks across cellular compartments and the specific roles of H2S in Cd stress tolerance.