title: The ectomycorrhizal basidiomycete Hebeloma cylindrosporum undergoes early waves of transcriptional reprogramming prior to symbiotic structures differentiation.
abstract: To clarify the early molecular interaction between ectomycorrhizal partners, we performed a RNA-Seq study of transcriptome reprogramming of the basidiomycete Hebeloma cylindrosporum before symbiotic structure differentiation with Pinus pinaster. Mycorrhiza transcriptome was studied for comparison. By reference to asymbiotic mycelium, 47 and 46 genes were specifically upregulated over fivefold (p ≤ 0.05) upon rhizosphere colonization and root adhesion respectively. Other 45 were upregulated throughout the symbiotic interaction, from rhizosphere colonization to differentiated mycorrhizas, whereas 274 were specifically upregulated in mycorrhizas. Although exoproteome represents 5.6% of H. cylindrosporum proteome, 38.5% of the genes upregulated upon pre-infectious root colonization encoded extracellular proteins. The proportion decreased to 23.5% in mycorrhizas. At all studied time points, mycorrhiza-induced small secreted proteins (MiSSPs), representing potential effectors, were over-represented among upregulated genes. This was also the case for carbohydrate-active enzymes (CAZymes). Several CAZymes were upregulated at all studied stages of the interaction. Consistent with a role in fungal morphogenesis and symbiotic interface differentiation, CAZymes over-expressed before and upon root attachment targeted fungal and both fungal and plant polysaccharides respectively. Different hydrophobins were upregulated upon early root adhesion, in mycorrhizas or throughout interaction. The functional classification of genes upregulated only in mycorrhizas pointed to intense metabolic activity and nutritional exchanges.
authors.affiliation: Ecologie Microbienne, Université de Lyon, F-69622, Lyon, France.|Université Lyon 1, CNRS, UMR5557, INRA, UMR1418, Villeurbanne, France.
authors.forename: Jeanne
authors.initials: J
authors.lastname: Doré
authors.affiliation: Interactions Arbres/Microorganismes, INRA-Nancy, INRA, UMR 1136 INRA-Université de Lorraine, Champenoux, 54280, France.
authors.forename: Annegret
authors.initials: A
authors.lastname: Kohler
authors.affiliation: Ecologie Microbienne, Université de Lyon, F-69622, Lyon, France.|Université Lyon 1, CNRS, UMR5557, INRA, UMR1418, Villeurbanne, France.
authors.forename: Audrey
authors.initials: A
authors.lastname: Dubost
authors.affiliation: U.S. Department of Energy Joint Genome Institute, Walnut Creek, CA, 94598, USA.
authors.forename: Hope
authors.initials: H
authors.lastname: Hundley
authors.affiliation: U.S. Department of Energy Joint Genome Institute, Walnut Creek, CA, 94598, USA.
authors.forename: Vasanth
authors.initials: V
authors.lastname: Singan
authors.affiliation: U.S. Department of Energy Joint Genome Institute, Walnut Creek, CA, 94598, USA.
authors.forename: Yi
authors.initials: Y
authors.lastname: Peng
authors.affiliation: U.S. Department of Energy Joint Genome Institute, Walnut Creek, CA, 94598, USA.
authors.forename: Alan
authors.initials: A
authors.lastname: Kuo
authors.affiliation: U.S. Department of Energy Joint Genome Institute, Walnut Creek, CA, 94598, USA.
authors.forename: Igor V
authors.initials: IV
authors.lastname: Grigoriev
authors.affiliation: Interactions Arbres/Microorganismes, INRA-Nancy, INRA, UMR 1136 INRA-Université de Lorraine, Champenoux, 54280, France.
authors.forename: Francis
authors.initials: F
authors.lastname: Martin
authors.affiliation: Ecologie Microbienne, Université de Lyon, F-69622, Lyon, France.|Université Lyon 1, CNRS, UMR5557, INRA, UMR1418, Villeurbanne, France.
authors.forename: Roland
authors.initials: R
authors.lastname: Marmeisse
authors.affiliation: Ecologie Microbienne, Université de Lyon, F-69622, Lyon, France.|Université Lyon 1, CNRS, UMR5557, INRA, UMR1418, Villeurbanne, France.
authors.forename: Gilles
authors.initials: G
authors.lastname: Gay
mesh_terms: D005656:Fungal Proteins / Q000235:genetics; D055364:Hebeloma / Q000235:genetics* / Q000254:growth & development / Q000302:isolation & purification / Q000502:physiology; D025282:Mycelium / Q000235:genetics / Q000254:growth & development / Q000302:isolation & purification; D038821:Mycorrhizae / Q000235:genetics* / Q000254:growth & development / Q000302:isolation & purification / Q000502:physiology; D028223:Pinus / Q000382:microbiology / Q000502:physiology; D018517:Plant Roots / Q000382:microbiology / Q000469:parasitology; D020543:Proteome / Q000235:genetics; D013559:Symbiosis; D059467:Transcriptome; D015854:Up-Regulation
chemical_list: D005656:Fungal Proteins; D020543:Proteome