Binding of nuclear proteins to the promoter region of the laccase gene Cs-lcs1 from the basidiomycete Ceriporiopsis subvermispora

The white rot basidiomycete Ceriporiopsis subvermispora secretes the ligninolytic enzymes manganese-dependent peroxidase (MnP) and laccase to the extracellular medium. The promoter region of the laccase gene (Cs-lcs1) possesses several putative metal responsive elements (MRE), as well as a putative target site responding to copper termed ACE, similar to the one found in yeast. In this work, we show by electrophoretic mobility-shift assays that the migration of DNA probes containing either MRE sites or the ACE element are retarded in their mobility after incubation with nuclear extracts from C. subvermispora. Competition experiments suggested the presence of defined binding proteins recognizing these elements.