Immunolocalization of hydrophobin HYDPt‐1 from the ectomycorrhizal basidiomycete Pisolithus tinctorius during colonization of Eucalyptus globulus roots

Abstract

Summary• The immunolocalization of one of the hydrophobins of Pisolithus tinctorius (HYDPt-1) is reported. Hydrophobin proteins play key roles in adhesion and aggregation of fungal hyphae, and it is already known that formation of ectomycorrhizas on eucalypt roots enhances the accumulation of hydrophobin mRNAs in the mycelium of Pisolithus tinctorius .• Purification of SDS-insoluble proteins from the mycelium of P. tinctorius showed the presence of a 13 kDa polypeptide with properties of class I hydrophobin.• Polyconal antibodies were raised against a recombinant HYDPt-1 polypeptide, and these were used for immunofluorescence-coupled transmission electron microscopy.• HYDPt-1 is a cell wall protein located at the surface of the hyphae with no preferential accumulation in the fungal cells of the different tissues of the ectomycorrhiza (i.e. extraradical hyphae, mantle or Hartig net).

Signal and nutrient exchange at biotrophic plant–fungus interfaces

“…hydrophobins and symbiosis-regulated acidic polypeptides) were identified. These proteins are likely to be involved in cell-cell adhesion at the symbiotic interface [5][6][7]. Similarly, putative cell-wall proteins at the interface in the AM symbiosis between Glomus versiforme and M. truncatula have been characterized [8].…”

Genome-wide analysis of cell wall-related genes in Tuber melanosporum

“…In addition to the contact with host surface, the fungal cell wall of ECM fungi is involved in both the adhesion events that occur during the mantle formation and in the creation of the symbiotic interface between the Hartig net hyphae and the root cells . The involvement of cell wall components during ECM development has already been investigated (Balestrini et al 1996;Laurent et al 1999;Martin et al 1999; Tagu et al 2001). Taking advantage of the recently released genome sequence of the Tuber melanosporum black truffle (Martin et al 2010), we have obtained a genome-wide inventory of the proteins that are involved in cell wall synthesis and remodeling.…”

Identification of a Hydrophobin Gene That is Developmentally Regulated in the Ectomycorrhizal Fungus Tricholoma terreum

“…In a pre-liminary study, only hydrophobins in the hyphal mantle were detected (37). A more thorough investigation using immunogold labeling of the protein in ultrathin sections of mycorrhiza detected hydrophobins in the Hartig net where every fungal cell was covered by hydrophobin (39). The influence of a hydrophobin layer on nutrient exchange is unclear, as the function of the symbiotic tissue is not impaired by rendering the surface of the hyphal wall impenetrable to water (27,39).…”

“…A more thorough investigation using immunogold labeling of the protein in ultrathin sections of mycorrhiza detected hydrophobins in the Hartig net where every fungal cell was covered by hydrophobin (39). The influence of a hydrophobin layer on nutrient exchange is unclear, as the function of the symbiotic tissue is not impaired by rendering the surface of the hyphal wall impenetrable to water (27,39). However, hydrophobins do not cover every portion of every hypha, and even in assembled Sc3 protein layers, pores are visible that permit diffusion of oligosugar or even oligopeptide moieties (51,53).…”