Sona is working to elucidate the physiological, genetic and metabolic networks involved in the plant’s response to environmental stresses. Her lab works with a class of evolutionary conserved proteins, the heterotrimeric G-proteins and a plant hormone abscisic acid (ABA).
Plants show a phenomenal degree of adaptation and phenotypic plasticity in response to different environmental conditions. The Pandey lab is taking complementary approaches using both model organisms as well as agronomically relevant crops to establish a foundation with discovery-based research and its translation to agricultural applications. The major focus areas of our research are:
- Heterotrimeric G-protein mediated signaling and plant adaptive responses
- Mapping ABA signaling networks in plants using comprehensive -omics approaches
HETEROTRIMERIC G-PROTEIN MEDIATED SIGNALING AND PLANT ADAPTIVE RESPONSES
Heterotrimeric G-proteins (referred to as G-proteins hereafter) consisting of Gα, Gβ and Gγ subunits and the Regulator of G-protein Signaling (RGS) proteins control some of the most important signaling pathways in all eukaryotes. The core of the G-protein signaling is conserved in all organisms, but critical differences exist in their function and regulation. In plants, G-proteins integrate a wide range of signals related to multiple hormones, environmental sensing, abiotic stresses and defense responses in order to ascertain optimal growth and development. The lab’s recent research in soybean has established that the networks of G-protein signaling in plants are significantly more diverse than previously thought and the current data show that G-proteins are involved in regulation of processes that directly affect plant yield: control of seed number and size, nodulation and abiotic stress responses. However, the mechanistic details of how G-proteins regulate these processes remain largely unknown. Our goal is to elucidate molecular mechanisms of the roles of G-protein complex during critical physiological responses and apply the knowledge gained to generate higher-yielding and stress-tolerance crops. Furthermore, to probe deeper into the unique mechanistic aspects of G-protein signaling mechanisms in plants, the lab is analyzing the details and regulation of G-protein signaling from across the evolutionary breadth of plant lineage.
MAPPING ABA SIGNALING NETWORKS IN PLANTS USING COMPREHENSIVE -OMICS APPROACHES
The role of ABA is obvious among plant hormones that link environmental signals to plant growth and development, due to its unique function in regulating both biotic and abiotic stress responses as well as controlling seed dormancy and water use efficiency of plants. Multiple ABA signaling modules have been established in plants and while the details of PYR/PYL/RCAR protein-dependent signaling module that uses the core of PP2C phosphatases and SnRK2 kinases has been most elegantly characterized, the progress in characterizing additional modules such as those mediated by G-proteins and lipid-derived second messengers remains relatively limited. They have previously reported on the role of GTG proteins in regulation of ABA signaling pathways mediated by G-proteins. Recombinant GTG proteins bind ABA and Arabidopsis plants lacking GTG genes (gtg1gtg2 double mutants) exhibit ABA hyposensitivity. However, the presence of multiple transmembrane domains in GTG proteins has made characterization of their detailed structure/function difficult. As an alternative, the lab plans to use extensive genomics, proteomics and lipidomics approaches with wild-type and G-protein-related mutants to elucidate their role in regulating ABA signaling.