Hydrogen sulfide: A versatile gaseous molecule in plants.

Hydrogen sulfide (HS) is a gasotransmitter and signaling molecule associated with seed germination, plant growth, organogenesis, photosynthesis, stomatal conductance, senescence, and post-harvesting. HS is produced in plants via both enzymatic and non-enzymatic pathways in different subcellular compartments. Exogenous application of HS facilitates versatile metabolic processes and antioxidant machinery in plants under normal and environmental stresses. This compound interacts with phytohormones like auxins, abscisic acid, gibberellins, ethylene, jasmonic acid, and salicylic acid. Furthermore, HS participates in signal transductions of other signaling molecules like nitric oxide, carbon monoxide, calcium, methylglyoxal, and hydrogen peroxide. It also mediates post-translational modification, which is a protective mechanism against oxidative damage of proteins. This review summarizes the roles of HS as intriguing molecule in plants.