Diversity and variability of NOD-like receptors in fungi
Résumé
NOD-like receptors (NLRs) are intracellular receptors that control innate immunity and other biotic interactions in animals and plants. NLRs have been characterized in plant and animal lineages, but in fungi, this gene family has not been systematically described. There is however previous indications of the involvement of NLR-like genes in non-self recognition and programmed cell death in fungi. We have analyzed 198 fungal genomes for the presence of NLRs and have annotated a total of 5616 NLR candidates. We describe their phylogenetic distribution, domain organization and evolution. Fungal NLRs are characterized by a great diversity of domain organizations, suggesting frequently occurring combinatorial assortments of different effector, NOD and repeat domains. The repeat domains are of the WD, ANK and TPR type; no LRR motifs were found. As previously documented for WD-repeat domains of fungal NLRs, TPR and ANK repeats evolve under positive selection and show highly conserved repeats and repeat length polymorphism, suggesting the possibility of concerted evolution of these repeats. We identify novel effector domains not previously found associated with NLRs, while others are related to effector domains of plant or animals NLRs. In particular, we show that the HET domain found in fungal NLRs may be related to TIR domains found in animal and plant immune receptors. This description of fungal NLR repertoires reveals both similarities and differences with plant and animals NLR collections, highlights the importance of domain re-assortment and repeat evolution and provides a novel entry point to explore the evolution of NLRs in eukaryotes.
Origine | Publication financée par une institution |
---|
Loading...