CRISPR mediated inactivation of OsPLDβ1 phospholipase enhances drought tolerance by upregulating stress-related genes and antioxidant enzymes in rice

Membrane lipids serve as precursors for intracellular signaling molecules, with the activation of phospholipases constituting an initial step in this process. Phospholipase D, a crucial family of enzymes that hydrolyze membrane lipids, plays a pivotal role in plant responses to stress. In this study, we used gene editing to disrupt the OsPLDβ1 function in rice and evaluated its performance under drought conditions. The Ospldβ1 mutants exhibited enhanced antioxidant enzyme activities, which led to reduced reactive oxygen species (ROS) accumulation, decreased seedling injury and mortality, and improved photosynthetic performance during drought stress. Additionally, the Ospldβ1 mutants exhibited lower levels of drought stress indicators, including lipid peroxidation, electrolyte leakage, and chlorophyll loss. The Ospldβ1 mutants showed lower ROS accumulation and better germination, and root development compared to the wild-type plants upon exposed to methyl viologen and mannitol. The expression other PLD family member genes ( OsPLDα,1 OsPLDα3 , OsPLDδ1 , OsPLDδ2 , OsPLDδ3 ) and stress responsive genes were upregulated in the Ospldβ1 mutant lines during the drought stress condition. This study investigated the negative function of the OsPLDβ1 gene in the drought tolerance mechanism. Deploying the Ospldβ1 allele in breeding programs may facilitate the development of climate-resilient crop cultivars to address the climate change situation. • The phospholipase D family members hydrolyze membrane lipids and play a pivotal role in stress responses in plants. • The loss of OsPLDβ1 function confers drought tolerance through the activation of other PLD family member genes and stress-responsive genes during drought stress. • Ospldβ1 mutants exhibited enhanced antioxidant enzyme activities, which led to decreased ROS accumulation and seedling mortality, and improved photosynthetic performance during drought stress.