Unravelling the Differential Expression of Potential microRNAs in Bacterial Wilt-resistant and Susceptible Ginger Species

Abstract

MicroRNAs (miRNA) have been shown to regulate plant pathogen interaction, by silencing genes, destructing or blocking of the translation of mRNA. However, their role in bacterial wilt, caused by Ralstonia solanacearum in ginger, has not been studied. In the present study, we utilized the transcriptome data from ginger-Ralstonia solanacearum interactions to characterize miRNAs from bacterial wilt-susceptible ginger (Zingiber officinale) and resistant mango ginger (Curcuma amada). The assembled mRNAs were utilized to generate miRNA targets and miRNAs. Considering the alignment results, we located a total of 2926 potential miRNA targets out of which 1551 were upregulated and 1419 were downregulated in ginger. In case of mango ginger, out of 2145 potential miRNA targets, 1506 were upregulated and 1594 were downregulated. In the resistance interactions with mango ginger, 1068 unique target genes were upregulated when compared to control. Gene Ontology (GO) analysis of differentially expressed target genes showed highest enrichment in response to cold, chloroplast and ATP binding in biological, cellular and molecular functions respectively. Nine target genes and their corresponding miRNAs were experimentally validated, which shows significant difference in expression with ginger-Ralstonia solanacearum interactions. The results will be very useful to disease resistant varieties of ginger.