Chloroplast activity provides invitro regeneration capability in contrasting cultivars

Existence of potent in vitro regeneration system is a prerequisite for efficient genetic transformation and functional genomics of crop plants. Little is known why only some cultivars in crop plants are tissue culture friendly? In this study, contrasting barley cultivars Golden Promise (GP) and DWRB91 (D91) were utilized for digging the molecular basis of regeneration efficiency. Multiomics studies involving transcriptomics, proteomics, metabolomics, and biochemical analysis were performed using GP and D91 callus to unravel the regulatory mechanisms. Transcriptomics analysis revealed 1487 differentially expressed genes (DEGs), in which 795 DEGs were upregulated and 692 DEGs were downregulated in the GP-D91 transcriptome. Genes encoding proteins localized in chloroplast and involved in ROS generation were upregulated in the embryogenic calli of GP. Moreover, proteome analysis by LC-MS revealed 3062 protein groups and 16989 peptide groups, out of these 1586 protein groups were differentially expressed proteins (DEPs). Eventually, GC-MS based metabolomics analysis also revealed the higher activity of plastids and alterations in key metabolic processes such as sugar metabolism, fatty acid biosynthesis, and secondary metabolism. Higher accumulation of sugars, amino acids and metabolites corresponding to lignin biosynthesis were observed in GP as compared to D91. Overall design: Comparative gene expression profiling analysis of RNA-seq data for barley callus (Hordeum vulagre cvs. Golden promise (GP) and DWR91 (D91)).