Bioinformatic analysis of heat–virus stress in Nicotiana benthamiana reveals promoter convergence and DNA-repair activation: Orthology-guided and RT-PCR-validated

This study investigated the molecular responses of Nicotiana benthamiana to combined heat stress and tobacco mosaic virus. Results indicated that the combined stresses were synergistic, leading to a ۴۹.۴% loss in plant height and ۵۲.۵% loss in leaf area. Transcriptome analysis of the plants indicated significant activation of the DNA repair pathways and the up-regulation of RAD۵۱ and XRCC۴ genes by ۳.۱۵- and ۴.۱۸-fold, respectively. Moreover, the convergence among promoters from genes responsive to combined stress was high, and the genes involved in DNA repair shared, on average, ۴.۵ regulatory elements. Confirmation of the results by Real-time PCR presented a high correlation (R² > ۰.۹۲) with the sequencing data. On the other hand, the data from the Comet assay confirmed more severe DNA damage under combined stress conditions. The study has shown that plants tackle combined stresses through integrated molecular mechanisms, whose understanding may be effective in developing varieties resistant to multiple stresses. Convergence at the promoter level and activation of the DNA repair system, among others, are some of the major strategies through which plants deal with such conditions.

کلیدواژه ها:

Combined stress ، Promoter convergence ، DNA repair ، Nicotiana benthamiana