Chemical control of the pathway leading to drought tolerance in plants

Resumen

In recent years, the impact of climate change has intensified water scarcity and irregular rainfall. These circumstances represent two significant challenges for plants, which, in turn, hinder crop productivity and pose a serious threat to the sustainability of agriculture.

At the plant level, major water loss occurs by transpiration when stomata are open, a process which is regulated by intrinsic signals such as the phytohormone Abscisic Acid (ABA). The characterisation of the proteins involved in the ABA pathway has led to a new field of research aimed at the discovery of ABA mimicking molecules. These molecules are capable to regulate exogenously stomata function thus, acting as agrochemical compounds against drought stress. The characterization of Nicotinic Acid as an ABA antagonist has provided a starting point for the discovery of Nicotinic acid related compounds with ABA related bioactivity.

This study employs the high-resolution structural information derived from the proteins involved in the ABA recognition pathway to find environmentally friendly agrochemical compounds that exogenously might control the ABA-dependent response of the pathway. For this purpose, an in silico screening of a library of compounds against ABA receptors was performed and the hits derived from this study were validated experimentally.

Docking studies, based on a self-made docking protocol, against a self-made database of natural compounds, gave rise to 4 hits whose experimental validation showed Nicotinamide Ribose (NR) as a possible eco-friendly candidate to control the ABA-dependent response of the pathway. Future in vitro assays on the other receptors of the family and in vivo assays in plants should be performed to corroborate this.