Heterologous gene expression in the basidiomycete fungus Coprinus cinereus

Summary Direct selection for TRP⁺ transformants of a trp-2 mutant of Coprinus cinereus showed that the gene mutation could be complemented by the heterologous gene from two other basidiomycete species, Schizophyllum commune (trp1) and Phanerochaete chrysosporium (trpC) but not by an ascomycete gene from Aspergillus nidulans (trpC). Cotransformation was used to confirm that the Aspergillus nidulans gene could be integrated but not expressed. Cotransformations were also used to show that the Aspergillus nidulans isocitrate lyase gene (acuD) and a construct containing the bacterial HygB gene fused to a hemibasidiomycete gene promotor from Ustilago maydis were also unexpressed in Coprinus cinereus.