Start Monday November 7th at 4pm (CET, Berlin/Paris)

(3 pm London/Lisbon, 10am New-York, 7am San Francisco, 5pm Tel Aviv)

Link to the Zoom conference: https://univ-grenoble-alpes-fr.zoom.us/j/91695622024?pwd=NjhjVXcrTGwrb3lIZThoRGd0WmsxZz09

Main Speaker: Amy Buck, co-Head of Institute for the Institute of Immunology & Infection Research, Edinburgh, UK (Link)

Title: Small RNAs in host-pathogen interactions: probing cross species RNA interference

Abstract:

RNA interference pathways play diverse functions in eurkaryotic gene regulation and viruses have evolved to take advantage of these pathways to manipulate the host cell and enable their life cycles. Research by ourselves and others has shown that viruses can do this through direct viral-host RNA-RNA interactions involving the RNA induced silencing complex (RISC). We previously found that murine cytomegalovirus directly interacts with miR-27 through a virus-encoded RNA and this leads to a degradation of miR-27 and de-regulation of its targets. We have extended our biochemical analysis of viral-host interactions to other viruses and found that an RNA virus also directly interacts with miR-27 to sequester this miRNA from its host targets.  Given the precedent for RNA-RNA interactions between pathogens and hosts, we have developed approaches to study whether and how extracellular pathogens also directly interact with their hosts using RNA.  I will discuss our latest work on RNA and extracellular vesicle trafficking between a gastrointestinal nematode, Heligmosomoides bakeri, and its mouse host where we have found a specific nematode Argonaute protein involved in RNA export.
 

Short session speaker (8 minutes long): Jose Roberto Bermudez Barrientos (post doc)

Title: Disentangling sRNA-Seq data to study RNA communication between species

Abstract:

Small RNAs (sRNAs) are an emergent means of cell-to-cell communication that can even travel between different species. Heligmosomoides bakeri is a model parasitic worm with immunosuppressive abilities attributed to its secretion products, including extracellular vesicles (EVs). These EVs contain different classes of sRNAs [1, 2], and their relevance for successful infection has not been tested. To address their relevance, it is crucial to determine which RNAs are produced by the nematode in the context of infection. The correct identification of parasite and host small RNAs in mixed sRNA-Seq libraries is challenging, especially for closely related organisms. We devised a strategy to disentangle sRNAs from mixed organisms [3], applied it to an in vitro experiment of mouse cells treated with nematode secretion products, identified more than 16 thousand different parasitic sRNAs and went on to predict targets in host transcripts. Our bioinformatic strategy can be widely applicable to other sRNA-mediated species communication models. We are currently dealing with the complexity of this predictions, which is a consequence of the high number of sRNAs being released, and working on more challenging experimental designs such as detecting parasite sRNAs in vivo in tissues of infected mice.