Meet our team
Dr. habil. Arne Weiberg
Principle investigator & group leader
Research Group Leader, Faculty of Biology, Genetics, Ludwig-Maximilians University Munich, Germany
Researcher at the Faculty of Mathematics & Natural Sciences, Biology, Christian-Albrechts University Kiel/Germany. Environmental Genomics, with Prof. Dr. Eva Stukenbrock
2010 – 2013
Postdoctoral position at the Plant Cell Biology, Plant Pathology & Microbiology Department, University of California, Riverside, United States of America, with Prof. Dr. Hailing Jin
2009 – 2010
Postdoctoral position at the Faculty of Agricultural Science, General Plant Pathology, Georg-August University Göttingen, Germany, with Prof. Dr. Andreas von Tiedemann
Habilitation in Genetics
Doctoral degree (Dr.agri.sci.), Faculty of Agricultural Science, Molecular Plant Pathology, Georg-August University Göttingen, Germany. Thesis title: Identification of genes induced in the vascular pathogen Verticillium longisporum by xylem sap metabolites of Brassica napus using an improved genome-wide quantitative cDNA-AFLP. Supervisor: Prof.Dr. Petr Karlovsky
Diploma, Faculty of Biology, Microbiology, Georg-August University Göttingen, Germany. Thesis title: Characterization of detoxification of the Fusarium-toxin Deoxynivalenol by the bacterial strain HOH107. Supervisors: PD Dr. Ruth Schmitz-Streit, Prof. Dr. Petr Karlovsky
In recent years, small RNAs have emerged as crucial components in the crosstalk between the necrotrophic fungus Botrytis cinerea and its plant hosts . However, it remains unclear if comparable strategies also evolved in diverse plant pathogens with different life styles and evolutionary origins. Oomycetes comprise dreadful crop pathogens, such as Phythophtora spp. causing late blight diseases on different crops. To elucidate the function of oomycete small RNAs during plant infection, I use the obligate biotrophic pathogen Hyaloperonospora arabidopsidis. This pathogen comprises a very narrow host range (infecting only the model plant Arabidopsis thaliana) and an absolute dependency on nutrients acquired via haustoria from living plant cells. The Hyaloperonospora reference genome enables a first insight into the RNAi machinery and I have determined a wide variety of small RNAs produced by Hyaloperonospora by small RNAseq analysis. In my current project, I am elucidating the functional roles of Hyaloperonospora small RNAs as suppressors of host immunity by molecular biology methods combined with next generation sequencing and phenotypic analysis of Arabidopsis mutants. Understanding the roles of RNAi and pathogen small RNAs in oomycete-plant interactions promise to provide future approaches to fight plant pathogenic oomycetes displaying massive threats to crop production and natural biodiversity.
Botrytis RNAi factors in cross-kingdom RNAi - Argonautes - RNA Dependent RNA Polymerases
The ascomycete Botrytis cinerea, the causative agent of grey mould disease in many crop plants, produces small non-coding RNAs (Bc-sRNAs) that translocate into plant cells during infection and hijack host RNA interference (RNAi) pathways to suppress host immunity genes. This mechanism has been described as cross-kingdom RNAi (Weiberg et al., Science, 2013).
I am interested in understanding the role of such pathogen small non-coding RNAs during plant-pathogen interactions, in particular how pathogen RNAs are delivered into plant cells to suppress host immunity genes. One hypothesis is that Botrytis small RNAs are encapsulated into extracellular vesicles (EVs), allowing a protection during the transport and delivery through the host cell membrane. On the molecular level, I am interested in learning, which RNA-binding proteins are involved in the small RNA translocation process during host infection.
Filamentous plant pathogens are historically known threads for global food security, shown in its extremes by an outbreak of Phytophthora infestans leading to the great famine in Ireland (Yoshida et al., Elife, 2013). In the addition to classic effector proteins, small RNAs (sRNAs) emerged as another class of effectors to modulate the interaction of plants and pathogens. The underlying mechanism termed cross-kingdom RNA interference (ck-RNAi) was first reported for the necrotrophic fungus Botrytis cinerea (Weiberg et al., Science, 2013). Recent studies further revealed ck-RNAi to contribute to the virulence of the fungal plant pathogens Puccina graminis (Wang et al., The New Phytologist, 2017) and Blumeria graminis (Kusch et al., Fungal Biology, 2018), as well as the oomycete Hyaloperonospora arabidopsidis (Dunker et al., Elife, 2020). This obligate biotrophic oomycete covers a narrow host range, including Arabidospsis thaliana and is the causing agent of the downy mildew disease (Koch and Slusarenko et al., The Plant Cell, 1990). However, our current understanding of ck-RNAi is still limited as a consequence of the proof of principal approaches in previous studies. In my current project, I want use whole transcriptome analysis coupled to other next generation sequencing approaches to generate a broader picture of the underlying mechanisms involved in ck-RNAi for the H. arabidopsidis-A. thaliana pathosystem. This knowledge could be beneficial for the usage of sustainable sRNA-based plant protection strategies.
Botrytis cinerea is a necrotrophic fungal pathogen causing the grey mould disease on many plant species. Recent reports discovered a remarkable phenomenon, which Botrytis and its host plants perform bidirectional cross kingdom-small RNA (ck-sRNA) exchange to affect the plant defense or fungal virulence (Weiberg et al., Science, 2013; Cai et al., Science, 2018). Among the gene silencing pathway, argonaute proteins are considered as one of the key players which carry small RNA to perform gene silencing at the complementary sequences, referred as RNA interference (RNAi) (Meister, Nature Reviews Genetics, 2013). Nevertheless, the roles of how plant ck- sRNAs perform the RNAi in the fungal pathogen and the functions of Botrytis argonaute (BcAGO) proteins remain unknown. In my project, on one hand, I hope to uncover whether plant ck-sRNAs are loaded into the BcAGO proteins to achieve gene silencing in Botrytis. On the other hand, I hope to understand the roles of BcAGOs related to the plant defense or fungal pathogenicity.
Cross-kingdom RNA interference is a natural phenomenon in plant-pathogen interactions. The fungal plant pathogen Botrytis cinerea sends small RNAs into plant cells during infection to silence host plant genes that promote infection. How are pathogen small RNAs delivered into target plant cells?
Extracellular vesicles (EVs) are new players in plant-pathogen interaction. I hypothesize that pathogen RNAs are translocated with EVs into plant cells. We have established protocols to prepare EVs from Botrytis cultures and found that EV samples contain Botrytis small RNAs. I am currently testing if Botrytis EVs can trigger cross-kingdom RNAi in host plants.