Location: Emerging Pests and Pathogens ResearchTitle: In planta expression and functional characterization of non-coding RNAs involved in detection and response to plant hosts in Dickeya dadantii
|GONZALEZ-TOBON, JULIANA - Cornell University|
Submitted to: American Phytopathological Society
Publication Type: Abstract Only
Publication Acceptance Date: 5/28/2021
Publication Date: 8/2/2021
Citation: Gonzalez-Tobon, J., Filiatrault, M.J. 2021. In planta expression and functional characterization of non-coding RNAs involved in detection and response to plant hosts in Dickeya dadantii. American Phytopathological Society. Online.
Technical Abstract: Dickeya sp. are necrotrophic bacterial pathogens that cause blackleg symptoms on potato and soft rot disease on many other plants. Similar to other plant pathogenic bacteria, it uses chemotaxis to sense plant defense compounds, find an opening, and enter the plant. Interestingly, Dickeya possesses an unusually high number of methyl-accepting chemoreceptors (MCPs) compared to other Enterobacterales, some of which have been shown crucial for disease. Long untranslated regions exist in the 5’ extreme of most MCPs in Dickeya. However, their role is unknown. RNASeq data from our lab shows they are transcriptionally active in planta. We hypothesize they harbor regulatory sequences such as small non-coding RNAs (ncRNAs) that control expression of downstream genes. Bioinformatic analyses supported this by revealing promoter and terminator motifs in key regulatory positions. As well, transcriptional start sites (TSSs) determined via CappableSeq, matched the start of the RNASeq-identified transcription peaks. The levels of transcription of these regions were validated using qRT-PCR assays in vitro and in planta (in susceptible and tolerant potato lines). RB-TnSeq, mutant generation and testing, transcriptional reporter fusions and two-component sensors, are currently being used to characterize the biological function of these regions and MCPs, as well as determine the signals they are responding to. The project provides important insights into regulatory mechanisms used by Dickeya when interacting with plants and thus might provide targets for control of these pathogens.