inda-STUDY-University of Delhi South Campus-2021-09-08 14:01:37.362-20
RNA-Seq analysis of rice varieties Nagina22 and IR64 in adult tissues of Flag leaf, inflorescence and root under control and field drought conditions.
The divergence of natural stress tolerance mechanisms is an intriguing phenomenon. To study it in rice, a comparative transcriptome analysis was carried out in heading stage tissue of flag leaf, panicles and roots of Nagina 22, a drought-tolerant and IR64, a drought-sensitive variety, subjected to field drought. Interestingly, N22 showed almost double the number of differentially expressed genes than IR64. Many DEGs colocalized within drought-related QTLs responsible for grain yield and drought tolerance and also associated with drought tolerance and critical drought-related plant traits such as leaf rolling, trehalose content, sucrose and cellulose content. Besides, co-expression analysis of the DEGs revealed several HUB genes known to actively regulate drought stress response. Strikingly, 1366 DEGs, including 21 HUB genes, showed a distinct opposite regulation in the two rice varieties under similar drought conditions. Annotation of these variety-specific DEGs  revealed that they are distributed in various biological pathways. Furthermore, 103 VS-DEGs were found to physically interact with over 1300 genes, including 32 that physically interact with other VS-DEGs as well. The promoter region of these genes have sequence variations among the two rice varieties, which might be in part responsible for their unique expression pattern.
The divergence of natural stress tolerance mechanisms is an intriguing phenomenon. To study it in rice, a comparative transcriptome analysis was carried out in heading stage tissue of flag leaf, panicles and roots of Nagina 22, a drought-tolerant and IR64, a drought-sensitive variety, subjected to field drought. Interestingly, N22 showed almost double the number of differentially expressed genes than IR64. Many DEGs colocalized within drought-related QTLs responsible for grain yield and drought tolerance and also associated with drought tolerance and critical drought-related plant traits such as leaf rolling, trehalose content, sucrose and cellulose content. Besides, co-expression analysis of the DEGs revealed several HUB genes known to actively regulate drought stress response. Strikingly, 1366 DEGs, including 21 HUB genes, showed a distinct opposite regulation in the two rice varieties under similar drought conditions. Annotation of these variety-specific DEGs  revealed that they are distributed in various biological pathways. Furthermore, 103 VS-DEGs were found to physically interact with over 1300 genes, including 32 that physically interact with other VS-DEGs as well. The promoter region of these genes have sequence variations among the two rice varieties, which might be in part responsible for their unique expression pattern.