Barrier breakthrough: Molecular determinants of exodermal divergence for root resilience

ongoing

As climate change intensifies, drought has emerged as one of the most severe abiotic stresses, significantly reducing crop yield. Reducing yield loss of crops is crucial by rethinking agriculture to ensure food security. Chickpea (Cicer arietinum), a major legume with high nutritional and several health benefits, is integral to the diets of millions and contributes to sustainable agriculture. However, chickpea faces significant annual yield losses (~50%) due to drought. The root exodermis, a specialized cell layer, plays a crucial role in water retention and protects against pathogens through cell wall barrier deposition. Despite its significance, the mechanisms governing exodermal barrier formation remain poorly understood, due to its absence in the model plant Arabidopsis. Recent findings from the host lab revealed that desi and kabuli chickpea varieties exhibit dynamic inducible and constitutive exodermal barriers differentiation, respectively. My objective is to investigate the underlying mechanism governing these exodermal responses and differentiation. First, I aim to elucidate the gene regulatory networks controlling this exodermal barrier formation through advanced transcriptomic approaches, involving single cell transcriptomic and time-course RNA-seq. These will reveal the developmental and stress-responsive pathways that orchestrate barrier formation. Second, I will test the role of key transcription factors (TFs)/genes through genetic modifications via hairy root transformation, molecular interaction and promoter activity assays. This will provide insights into how these regulators regulate this barrier differentiation, and stress response that impact barrier traits. The novel insights gained from this proposal will not only advance our understanding of cell-type-specific stress responses, but facilitate its translation for targeted breeding strategies aim at enhancing stress resilience and improving crop yield.