title: Cgl-SLT2 is required for appressorium formation, sporulation and pathogenicity in Colletotrichum gloeosporioides.
abstract: The mitogen-activated protein (MAP) kinase pathways has been implicated in the pathogenicity of various pathogenic fungi and plays important roles in regulating pathogenicity-related morphogenesis. This work describes the isolation and characterization of MAP kinase gene, Cgl-SLT2, from Colletotrichum gloeosporioides. A DNA sequence, including 1,633 bp of Cgl-SLT2 open-reading frame and its promoter and terminator regions, was isolated via DNA walking and cloned. To analyze gene function, a gene disruption cassette containing hygromycin-resistant gene was constructed, and Cgl-SLT2 was inactivated via gene deletion. Analysis on Cgl-slt2 mutant revealed a defect in vegetative growth and sporulation as compared to the wild-type strain. When grown under nutrient-limiting conditions, hyperbranched hyphal morphology was observed in the mutant. Conidia induction for germination on rubber wax-coated hard surfaces revealed no differences in the percentage of conidial germination between the wild-type and Cgl-slt2 mutant. However, the percentage of appressorium formation in the mutant was greatly reduced. Bipolar germination in the mutant was higher than in the wild-type at 8-h post-induction. A pathogenicity assay revealed that the mutant was unable to infect either wounded or unwounded mangoes. These results suggest that the Cgl-SLT2 MAP kinase is required for C. gloeosporioides conidiation, polarized growth, appressorium formation and pathogenicity.
authors.affiliation: School of Biosciences and Biotechnology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, Bangi, Selangor, Malaysia.
authors.forename: H Y
authors.initials: HY
authors.lastname: Yong
authors.affiliation: School of Biosciences and Biotechnology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, Bangi, Selangor, Malaysia.
authors.forename: F D A
authors.initials: FD
authors.lastname: Bakar
authors.affiliation: Department of Bioprocess Engineering, Faculty of Chemical and Natural Resources Engineering, Universiti Teknologi Malaysia, Skudai, Johor, Malaysia.
authors.forename: R M
authors.initials: RM
authors.lastname: Illias
authors.affiliation: Malaysia Genome Institute, Jalan Bangi, Kajang, Selangor, Malaysia.
authors.forename: N M
authors.initials: NM
authors.lastname: Mahadi
authors.affiliation: School of Biosciences and Biotechnology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, Bangi, Selangor, Malaysia.
authors.forename: A M A
authors.initials: AM
authors.lastname: Murad
mesh_terms: D003001:Cloning, Molecular; D020231:Colletotrichum / Q000254:growth & development* / Q000472:pathogenicity*; D004271:DNA, Fungal / Q000737:chemistry / Q000235:genetics; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism*; D017353:Gene Deletion; D025301:Hyphae / Q000254:growth & development; D031022:Mangifera / Q000382:microbiology; D020928:Mitogen-Activated Protein Kinases / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D016254:Mutagenesis, Insertional; D016366:Open Reading Frames; D010935:Plant Diseases / Q000382:microbiology; D011401:Promoter Regions, Genetic; D017422:Sequence Analysis, DNA; D013172:Spores, Fungal / Q000254:growth & development*; D014774:Virulence
chemical_list: D004271:DNA, Fungal; D005656:Fungal Proteins; D020928:Mitogen-Activated Protein Kinases
keywords: Colletotrichum gloeosporioides; MAP kinase; appressorium; pathogenicity