The pmk1-like mitogen-activated protein kinase from Lecanicillium (Verticillium) fungicola is not required for virulence on Agaricus bisporus.
In plant-pathogenic fungi, the pmk1 mitogen-activated protein kinase (MAPK) signalling pathway plays an essential role in regulating the development of penetration structures and the sensing of host-derived cues, but its role in other pathosystems such as fungal-fungal interactions is less clear. We report the use of a gene disruption strategy to investigate the pmk1-like MAPK, Lf pmk1 in the development of Lecanicillium fungicola (formerly Verticillium fungicola) infection on the cultivated mushroom Agaricus bisporus. Lf pmk1 was isolated using a degenerate PCR-based approach and was shown to be present in a single copy by Southern blot analysis. Quantitative RT-PCR showed the transcript to be fivefold upregulated in cap lesions compared with pure culture. Agrobacterium-mediated targeted disruption was used to delete a central portion of the Lf pmk1 gene. The resulting mutants showed normal symptom development as assessed by A. bisporus mushroom cap assays, sporulation patterns were normal and there were no apparent changes in overall growth rates. Our results indicate that, unlike the situation in fungal-plant pathogens, the pmk1-like MAPK pathway is not required for virulence in the fungal-fungal interaction between the L. fungicola pathogen and A. bisporus host. This observation may be of wider significance in other fungal-fungal and/or fungal-invertebrate interactions.
Collopy
Patrick D
PD
School of Biological Sciences, University of Bristol, Bristol BS8 1UG, UK.
Amey
Richard C
RC
School of Biological Sciences, University of Bristol, Bristol BS8 1UG, UK.
Sergeant
Martin J
MJ
Warwick HRI, University of Warwick, Wellesbourne, Warwick CV35 9EF, UK.
Challen
Michael P
MP
Warwick HRI, University of Warwick, Wellesbourne, Warwick CV35 9EF, UK.
Mills
Peter R
PR
Warwick HRI, University of Warwick, Wellesbourne, Warwick CV35 9EF, UK.
Foster
Gary D
GD
School of Biological Sciences, University of Bristol, Bristol BS8 1UG, UK.
Bailey
Andy M
AM
School of Biological Sciences, University of Bristol, Bristol BS8 1UG, UK.
D000364:Agaricus / Q000502:physiology*; D015139:Blotting, Southern; D005656:Fungal Proteins / Q000235:genetics / Q000302:isolation & purification / Q000502:physiology*; D005800:Genes, Fungal; D020928:Mitogen-Activated Protein Kinases / Q000235:genetics / Q000302:isolation & purification / Q000502:physiology*; D010641:Phenotype; D016133:Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014170:Transformation, Genetic; D020172:Verticillium / Q000201:enzymology* / Q000235:genetics / Q000472:pathogenicity*; D014774:Virulence
D005656:Fungal Proteins; D020928:Mitogen-Activated Protein Kinases