Project Details
Projekt
The role of Hfq and exRNAs in plant infections with Xylella fastidiosa
Applicant
Professorin Dr. Silke Robatzek
Subject Area
Organismic Interactions, Chemical Ecology and Microbiomes of Plant Systems
Plant Breeding and Plant Pathology
Plant Breeding and Plant Pathology
Term
since 2020
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 433194101
This project addresses crop vascular diseases by Xylella fastidiosa (Xf), a complex problem in agriculture, and will elucidate the process of bacterial vesiculation in host interactions. We hypothesize that Type-III lacking Xf uses extracellular vesicles (EVs) to secrete immunomodulatory effectors including extracellular (ex)RNAs. This is supported by findings of the 1st funding period, showing that small (s)RNAs, messenger (m)RNAs and RNA binding proteins (RBPs) e.g. tRNA ligases and Hfq were associated with Xf-EVs. Given that Hfq has been implicated in bacterial RNA interference (RNAi), in the 2nd funding period, we aim at obtaining an understanding i) of RNA EV loading, including the phenotypic characterizing Δhfq mutants and identifying Hfq-bound RNAs and complexes. This will be possible in collaboration with C1 Goesmann and B2 Kehr. Encouraged by our initial observations of dsRNA-mediated antibacterial gene silencing, we will improve our spray-induced gene silencing (SIGS) and host-induced gene silencing (HIGS) strategies by designing RNAs compatible for Hfq (with A6 Šečić). ii) In collaboration with A4 Weiberg, we will evaluate infection-relevant evRNAs, investigating their predicted plant targets by phenotyping respective genetic mutants and reporter lines capturing evRNAs. iii) Given the likely genetic redundancies within the Argonaut (AGO) gene family and thus benefitting from tools available from B5 Meister, we will address the role of AGO in host gene targeting by Xf sRNAs in Arabidopsis thaliana and if time permits, in olive. This will contribute to AGO research activities of several groups and comparative studies within the RU5116. With B5 Meister, we will also explore an “anchor-away” approach transgenically expressing TNRC6-like peptides. iv) To examine cross-kingdom (ck)RNA transfer, we will collaborate with A4 Weiberg and B3 Feldbrügge, and deploy state-of-the-art reporter systems. Our aim is to establish a role for bacterial evRNAs during infection, that when understood, could be used to develop RNA-based strategies against Xf and genetically engineered crops resistant to evRNAs from Xf.
DFG Programme
Research Units
