Identification, Isolation, and Expression Profiling of Abiotic Stress Responsive Genes under Phosphorus and Drought Stress Conditions in Vigna radiata

Abstract

Drought stress is a significant threat to agricultural yields, and the frequency and intensity of drought events are projected to rise in the coming years as a consequence of global climate change. Particularly, in short-duration crops like Vigna radiata (mungbean), which is a legume kharif crop cultivated in Asia, drought severely affects the morpho-physiological, biochemical, and molecular functioning of the plants. Phosphorus is important in root development and nutrient absorption. Plant growth promoting rhizobacteria have various functions. PIP genes assist with water transportation in drought conditions. The current investigation involved the in-silico characterization of plasma membrane intrinsic protein (PIP) in Vigna radiata. A total of 13 VrPIP genes have been identified in Vigna radiata. All these 13 VrPIP are categorized into two distinct subgroups much like how they were previously defined in Arabidopsis thaliana which are disturbed evenly across 9 out of 11 chromosomes. These genes contain a common asparagine-proline-alanine (NPA) domain and the conservation of eight conserved motif blocks was also analyzed. Through in-silico analysis, various cis-elements and functional variations were identified, including promoter-associated, development-related, abiotic stress-responsive, light-responsive, and hormone-responsive elements. A significant number of proteins were found to be involved in water transport based on gene ontology annotations. Plasma membrane intrinsic proteins were localized to the plasma membrane. Assessments showed that VrPIP proteins interact with other proteins, thereby regulating signaling cascades. VrPIP10 gene was checked for drought stress with phosphorus and PGPR treatments. The expression profiling results indicate significant variation in PIP10 gene expression under phosphorus, PGPR, and drought conditions. This variation occurs during early, flowering, and rewatering stages in both NCM-13 and MSPS-119. PIPs are early responsive genes with high fold change observed in both varieties during the early stage. Expression decreases during flowering and rewatering due to phosphorus and PGPR application. These treatments have synergistic effects and enhance crop resilience. The expression analysis demonstrates that MSPS-119 performs better than NCM-13. Integrating these findings into mung bean cultivation, especially in drought-prone areas, can improve yields and promote sustainable agriculture.