NLR multidomain proteins largely mediate the immune response in plants. These immune receptors are the key elements in the recognition of the pathogen leading to plant susceptibility or resistance. Our collaborators in the BGPI (Biology and Genetics of Plant-Parasite Interactions) of the Inra center in Montpellier are interested in the interactions between rice and the phytopathogenic fungus Magnaporthe oryzae. Rice is the main food source for half of the world's population, and crop sustainability is a major public health issue. For several years, CBS's team "Structure, Dynamics and Function of Biomolecules by NMR" has undertaken a collaboration to better understand the molecular mechanisms involved in host-pathogen recognition. A nuclear magnetic resonance approach as well as in vitro and in vivo tests of protein-protein interactions have been made and allow to propose a model explaining the recognition process that implies in particular the receptor integrated decoy domain. This model suggests that fungus effectors (proteins acting as virulence factors) are recognized by the integrated decoy domain but that this recognition also involves synergy with other domains of the immune receptor.To ensure proper growth, bacterial genome must be faithfully segregated so that each daughter cell, resulting from cellular division, inherits an identical copy of the mother cell genetic material. Segregation of bacterial genomes is ensured by an active system, called partition system, allowing the separation and the positioning of newly replicated DNA. By using fluorescence super-resolution microscopy techniques, the team of Marcelo Nollmann, in collaboration with the team of Jean-Yves Bouet at the Laboratoire de microbiologie et génétique moléculaires of Toulouse, reveals a new model in which the nucleoid provides a scaffold to guide the proper segregation of partition complexes. This work is published in the nature magazine Nature Communications.
Host-pathogen recognition by the integrated decoy model
Recognition of the Magnaporthe oryzae effector AVR-Pia by the decoy domain of the rice NLR immune receptor RGA5.