title: CFP, the putative cercosporin transporter of Cercospora kikuchii, is required for wild type cercosporin production, resistance, and virulence on soybean.
abstract: Many species of the fungal genus Cercospora, including the soybean pathogen C. kikuchii, produce the phytotoxic polyketide cercosporin. Cercosporin production is induced by light. Previously, we identified several cDNA clones of mRNA transcripts that exhibited light-enhanced accumulation in C. kikuchii. Targeted disruption of the genomic copy of one of these, now designated CFP (cercosporin facilitator protein), results in a drastic reduction in cercosporin production, greatly reduced virulence of the fungus to soybean, and increased sensitivity to exogenous cercosporin. Sequence analysis of CFP reveals an 1,821-bp open reading frame encoding a 65.4-kDa protein similar to several members of the major facilitator superfamily (MFS) of integral membrane transporter proteins known to confer resistance to various antibiotics and toxins in fungi and bacteria. We propose that CFP encodes a cercosporin transporter that contributes resistance to cercosporin by actively exporting cercosporin, thus maintaining low cellular concentrations of the toxin.
authors.affiliation: Agricultural Research Service, U.S. Department of Agriculture, North Carolina State University, Raleigh 27695-7616, USA.
authors.forename: T M
authors.initials: TM
authors.lastname: Callahan
authors.forename: M S
authors.initials: MS
authors.lastname: Rose
authors.forename: M J
authors.initials: MJ
authors.lastname: Meade
authors.forename: M
authors.initials: M
authors.lastname: Ehrenshaft
authors.forename: R G
authors.initials: RG
authors.lastname: Upchurch
mesh_terms: D000595:Amino Acid Sequence; D001203:Ascomycota / Q000235:genetics / Q000472:pathogenicity* / Q000502:physiology*; D001483:Base Sequence; D002352:Carrier Proteins / Q000235:genetics* / Q000378:metabolism*; D004271:DNA, Fungal / Q000235:genetics; D005656:Fungal Proteins / Q000235:genetics* / Q000378:metabolism*; D005816:Genetic Complementation Test; D026901:Membrane Transport Proteins; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D010569:Perylene / Q000031:analogs & derivatives* / Q000378:metabolism; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D013025:Glycine max / Q000382:microbiology*; D014774:Virulence
chemical_list: D002352:Carrier Proteins; D004271:DNA, Fungal; D005656:Fungal Proteins; D026901:Membrane Transport Proteins; C400126:cercosporin transporter protein, Cercospora; D010569:Perylene; C026363:cercosporin