Signaling by hydrogen sulfide and cyanide through post-translational modification

Area of Science:

• Plant Physiology
• Biochemistry
• Molecular Biology

Background:

• Hydrogen sulfide and hydrogen cyanide were historically viewed as toxic compounds.
• Emerging evidence highlights their roles as signaling molecules in plants.
• These molecules are involved in crucial metabolic pathways and stress responses.

Purpose of the Study:

• To elucidate the signaling roles of hydrogen sulfide and hydrogen cyanide in plants.
• To understand the mechanisms by which these molecules regulate plant processes.
• To explore their involvement in post-translational modifications of proteins.

Main Methods:

• Investigated the production pathways of hydrogen sulfide and hydrogen cyanide in plants.
• Analyzed the effects of these molecules on plant adaptation, development, and stress responses.
• Examined the post-translational modifications, persulfidation and S-cyanylation, of protein cysteine residues.

Main Results:

• Hydrogen sulfide, produced in various cellular compartments, regulates photosynthesis, autophagy, and stomatal movement.
• Hydrogen cyanide, generated during ethylene and camalexin biosynthesis, influences seed dormancy and biotic stress responses.
• Both molecules exert their functions by modifying protein cysteine thiols, leading to persulfidation (sulfide) and S-cyanylation (cyanide).

Conclusions:

• Hydrogen sulfide and hydrogen cyanide act as essential signaling molecules in plants, not just toxic agents.
• Persulfidation and S-cyanylation are key mechanisms by which these molecules modulate protein function.
• Understanding these signaling pathways is crucial for plant adaptation, development, and stress resilience.