Investigate the dynamic transcriptional reprogramming in Medicago truncatula nad1 mutant nodules

In order to investigate the dynamic transcriptional reprogramming in nad1 mutant nodules, differentially expressed genes in root nodules were analyzed using an RNA-seq technique. DEGs between WT nodules and WT nodule-stripped roots revealed that a large number of genes displayed differential expression in WT Nod vs WT R, which is consistent with a previous report that has similar number of DEGs. Among DEGs in WT Nod vs WT R, 49% of genes were upregulated and the rest were downregulated. Similarly, in nad1-1 mutant nodules vs WT Nod, 55% were upregulated and 45% were downregulated. We focused on the gene families representative of the interesting transcriptional reprogramming from the symbiosis features in WT nodules to the defense features in mutant nodules. It revealed that defense-related gene families were largely repressed and even switched-off in WT Nod vs WT R, but were elevated in mut Nod vs WT Nod.