Plant signaling mediated by sulfide and cyanide

Plants are able to transform inorganic sulfur compounds into cysteine, which is an organic reduced sulfur compound. Currently, the most novel aspect of plant research on sulfur, to which our research group has provided essential contributions, is focused on plant signaling by molecules related to cysteine, such as sulfide and cyanide. We have proposed a fundamental change in concept, i.e., sulfur compounds and related molecules perform signaling roles rather than metabolic functions. When we compare sulfide and cyanide with previously recognized signaling molecules, we observe that both molecules meet all the requirements for signaling.

Hydrogen sulfide is already accepted as a regulator of essential life processes in animals and plants. Our research has demonstrated the role of the sulfide as a signaling molecule that regulates the autophagy and the abscisic acid-dependent stomatal movement. We have also concluded that sulfide represses autophagy via a mechanism that is independent of redox conditions. Cyanide is produced in significant amounts in the plant and should be maintained below the toxic concentration threshold. Specifically, our investigation provided insight into the role of endogenously produced cyanide in Arabidopsis in which is essential for proper root hair development and for the modulation of the plant immune system.

The main role of this intership will be to try to accopmplish some of the following objetives. Regarding sulfide, the objetives are to broaden the range of essential plant processes that are signaled by sulfide and deepen our understanding of the underlying mechanisms. The objectives regarding cyanide are to demonstrate that it acts as a signaling molecule that regulates processes that are essential for plant performance and to decipher the underlying mechanisms.