A clone resource of Magnaporthe oryzae effectors that share sequence and structural similarities across host-specific lineages
Creators: name: Petit-Houdenot, Yohann
name: Langner, Thorsten
name: Harant, Adeline
name: Win, Joe
name: Kamoun, Sophien
Publisher: name: Zenodo
Year: 2019
Subjects: plant pathology
fungi
virulence
molecular biology

description: <em>Now published in Molecular Plant-Microbe Interactions 33:1032-1035</em> <strong>We describe a clone resource of 195 effectors of the blast fungus <em>Magnaporthe oryzae</em>. These clones are freely available as Golden Gate compatible entry plasmids. Our aim is to provide the community with an open source effector clone library to be used in a variety of functional studies.</strong> Plant pathogens secrete effectors that play central roles in subjugating plants for colonization. Effectors typically have signal peptides, and occasionally carry conserved folds and motifs (Lo Presti <em>et al.,</em>2015; Franceschetti<em>et al.</em>, 2017). <em>Magnaporthe </em><em>oryzae</em>(Syn. <em>Pyricularia oryzae</em>) is an important plant pathogenthat is able to infect around 50 species of both wild and cultivated grasses including important cereals of the Poaceae family. <em>M. oryzae</em>is mostly known to cause rice blast but can also cause disease on other crops such as barley, wheat, foxtail millet, and finger millet. The global population of <em>Magnaporthe </em>is composed of genetically differentiated lineages which, in some cases, still exhibit a measurable degree of gene flow (Gladieux <em>et al.,</em>2018). Fungal isolates from each of those lineages show a preference for a specific host and also encode distinct repertoires of effector genes (Yoshida <em>et al.,</em>2016). The first genomic sequence of <em>Magnaporthe oryzae</em>was released in 2005 for the lab strain 70-15 and allowed to predict a large set of secreted proteins such as enzymes involved in secondary metabolism and virulence-associated factors including putative effectors (Dean <em>et al.,</em>2005). Recently an increasing number of genome sequences of isolates from different lineages have become available, allowing the research community to perform comparative genomic studies (Chiapello <em>et al.,</em>2015; Yoshida <em>et al.,</em>2016). Many of the validated effectors of <em>M. </em><em>oryzae</em> are known as the MAX (<strong><em>M</em></strong><em>agnaporthe</em><strong>A</strong>VRs and To<strong>x</strong>B like) effectors. These effectors, while showing little primary sequence similarity, share a conserved structural fold composed of 6 β-sheets alternating in an anti-parallel manner (de Guillen<em>et al., </em>2015). The MAX family has been largely expanded in <em>Magnaporthe</em>as those effectors account for 5-10% of the effector repertoire and for 50% of the already cloned effectors of <em>Magnaporthe</em>(de Guillen<em>et al., </em>2015). Indeed, the identification of structural motifs enables more sensitive predictions of effectors from pathogen genomes compared to sequence similarity searches (Franceschetti<em>et al.</em>, 2017). The aim of this project was to computationally identify a set of <em>M. oryzae</em>effectors from the main host-specific lineages and develop an open access clone resource for functional analyses.