Title : Integrated transcriptome and small RNA sequencing of contrasting lentil (Lens culinaris Medik.) genotypes delineates the miRNA-mediated transcriptional networks underlying Fe deficiency stress in lentil
Abstract:
Iron is a crucial micronutrient for plants and its deficiency in alkaline soil limits the crop productivity. MicroRNAs (miRNAs) play crucial in nutrient deficiencies in plants. However, the role of miRNAs and their targets in response to iron deficiency stress is less known. In order to identify the role of miRNAs in regulating iron metabolism and iron deficiency response in lentil, integrated small RNA sequencing and transcriptome sequencing was performed. A total of 7,613 differentially expressed mRNAs (DEGs) were identified. Analysis of miRNA libraries resulted in identification of 175 miRNAs including 120 conserved and 55 novel miRNAs. Phylogenetic analysis of precursor sequences of these miRNAs revealed their ancestral relationships. Differential expression analysis identified 23 differentially expressed miRNAs (DEMs) upon iron deficiency stress. Integrated analysis resulted in 2,386 potential targets of identified DEMs. Real time expression analysis was conducted for validating the antagonistic expression pattern of selected miRNA-mRNA pairs. One candidate was selected on the basis of expression analysis i.e., miRNA397 targeting laccase. Functional characterization using overexpression lines generated through hairy root transformation approach displayed reduced ROS accumulation and lignin deposition and improved tolerance to iron deficiency tolerance in lentil. This study lays the foundation for future iron related studies in lentil and could provide important miRNA-mRNA pairs for developing improved lentil cultivars.
