Identification of laccase‐like genes in ectomycorrhizal basidiomycetes and transcriptional regulation by nitrogen in Piloderma byssinum

• Ectomycorrhizal (ECM) fungi were screened for laccase-like genes by polymerase chain reaction (PCR) using primers for white rot fungal laccase genes, and expression of the genes was examined by reverse transcriptase polymerase chain reaction (RT-PCR) for Piloderma byssinum in axenic culture under different nutrient conditions. • Laccase-like genes were present in Rhizopogon roseolus along with several Russulales and Atheliaceae taxa, and showed strong nucleotide sequence similarity to laccase genes in white rot fungi. Multiple laccase-like genes were only identified in Piloderma spp. • Laccase-like genes were expressed in Piloderma spp., with transcript levels some six times higher under high nitrogen conditions in P. byssinum than when nitrogen availability was lower. • The potential roles of laccases in nutrient mobilization and/or differentiation of multihyphal ECM fungal structures are discussed.