Regulation of Long Noncoding RNAs Responsive to Phytoplasma Infection in Paulownia tomentosa

摘要

Paulownia witches’ broom caused by phytoplasma infection affects the production of Paulownia trees worldwide. Emerging evidence showed that long noncoding RNAs (IncRNA) play a protagonist role in regulating the expression of genes in plants. So far,the identification of IncRNAs has been limited to a few model plant species, and their roles in mediating responses to Paulownia tomentosa that free of phytoplasma infection are yet to be characterized. Here, whole-genome identification of IncRNAs, basedon strand-specific RNA sequencing, from four Paulownia tomentosa samples, was performed and identified 3689 IncRNAs. These IncRNAs showed low conservation among plant species and some of them were miRNA precursors. Further analysis revealed that the 112identified IncRNAs were related to phytoplasma infection. We predicted the target genes of these phytoplasma-responsive IncRNAs, and our analysis showed that 51 of the predicted target genes were alternatively spliced. Moreover, we found the expressionof the IncRNAs plays vital roles in regulating the genes involved in the reactive oxygen species induced hypersensitive response and effector-triggered immunity in phytoplasma-infected Paulownia. This study indicated that diverse sets of IncRNAs were responsive to Paulownia witches’ broom, and the results will provide a starting point to understand the functions and regulatory mechanisms of Paulownia IncRNAs in the future.