Dynamic Landscape of Mitochondrial Cytidine-To-Uridine RNA Editing in Tobacco (Nicotiana Tabacum) Shows its Tissue Specificity

Abstract The Cytidine-to-Uridine (C-to-U) RNA editing is a prevalent nucleoside modification at RNA level in plants. However, it is unclear whether the dynamics of C-to-U RNA editing is related to its tissues. In this study, we explored the tissue specificity of mitochondrial RNA editing based on RNA-seq data from tobacco (Nicotiana tabacum) root, stem, leaf, and flower tissues. As a result, a total of 331 RNA editing sites involving in 54 mitochondrial genes were identified. Among these identified RNA editing sites, 78 sites were confirmed tissues-specific. The results revealed dynamic landscape of conserved editing sites in editing efficiency among different tissues. To investigate the mechanism of tissue specificity of mitochondrial RNA editing in Nicotiana tabacum, the expression of RNA editing factor PPR genes was analyzed. The result shows that the expression level of PPR genes in each tissue also varies from different tissues, indicating the heterogeneity of RNA editing in different tissues might result from the tissue specificity of PPR genes expression. Our analyses provide insights into understanding landscape, regulation and function of RNA editing events in plants.