RESEARCH LINES
Plant adaptation mechanisms in a tomato RIL population with different abiotic stress combination tolerance
A population of tomato recombinant inbred lines (RILs) with different sensitivity to the combination of salinity and heat is used to decipher the physiological, biochemical and molecular markers that are specific to this combination by comparing tolerant and sensitive genotypes. We then try to integrate the results in different known metabolic pathways to obtain complete and detailed information on the specific mechanisms involved in the development of tolerance. We also characterize how fruit yield and quality are affected by stress combinations and which characters are more susceptible to abiotic stress combinations.
N metabolism and amino acids biosynthesis is differentially and specifically regulated by the combination of salinity and heat as compared to single stress.
Sugar synthesis, transport and accumulation is affected differentially in tomato fruits grown under simulated field conditions (SFC)
ABA-dependent and ABA-independent specific signaling mechanisms under abiotic stress combinations
Plant hormones might be a key regulator of the tailored responses of plants to different stress combinations because hormone signaling can be flexibly modulated depending on the types of environmental stresses as it has been extensively published. In addition, different types of stresses that oppositely affect hormone synthesis and signaling can simultaneously occur in nature. Thus, precise regulation of hormone synthesis and signaling should be required for the acclimation of plants to various combinations of stresses.
Abscisic acid (ABA) has long been known to play an integral role in the response of plants to abiotic stresses. ABA functions as a key regulator of stomatal closure to prevent excess water loss through transpiration under water deficiency and salt stress. ABA also activates signaling pathways involving many stress-responsive genes and other regulatory genes required for the acclimation of plants to abiotic stresses. Recent studies suggested that ABA might be involved in the tailored response of plants to the drought and heat stress combination as well as drought or heat stress applied individually. Our research group, through the use and integration of different physiological, biochemical, different -omics and bioinformatics tools tries to elucidate those ABA-dependent and ABA-independent molecular cues that can trigger plant adaptation to abiotic stress combinations.
Dissecting ABA-independent specific targets under abiotic stress combinations using ABA-deficient mutants
ROS and NO signaling mechanisms and interplay under abiotic stress combinations
Synthesis and accumulation of reactive oxygen, nitrogen and sulfur species (ROS, RNS and RSS, respectively) are well-established mechanisms occurring under any abiotic stress condition. These molecules have a dual activity, as they participate in signaling processes under physiological conditions, but, under stress conditions, their production increases, interacting with each other and modifying and-or damaging the main cellular components: lipids, carbohydrates, nucleic acids and proteins. The latter have amino acids in their sequence that are susceptible to post-translational modifications, both reversible and irreversible, through the different reactive species generated by abiotic stresses (redox-based PTMs). Some research suggests that this process does not occur randomly, but that the modification of critical residues in enzymes modulates their biological activity, being able to enhance or inhibit complete metabolic pathways in the process of acclimation and tolerance to the exposure to different abiotic stresses. Our research group work in the elucidation of these specific signaling mechanisms at transcriptomic and proteomic levels that might be different under abiotic stress combination from those known occurring under single stress.
Melatonin as a signaling molecule under abiotic stress combinations
Melatonin (MEL), a ubiquitous indolamine molecule, has gained interest in the last few decades due to its regulatory role in plant metabolism. It has been recently shown that MEL and NO can interact at multiple levels under abiotic stress, starting with their own biosynthetic pathways and inducing a particular signaling response in plants. Due to the impact of climate-change-related abiotic stresses on agriculture, the role of these molecules and their interplay with ROS in mediating abiotic stress combination tolerance and the main mechanisms by which they operate is among our research interests, from the regulation of the entire antioxidant defense system to the post-translational modifications (PTMs) of important molecules.
