Molecular Plant-Microbe Interactions (2000) 13, 374-383

Yoshitaka Takano, Taisei Kikuchi, Yasuyuki Kubo, John E. Hamer, Kazuyuki Mise and Iwao Furusawa (2000)
The Colletotrichum lagenarium MAP kinase gene CMK1 regulates diverse aspects of fungal pathogenesis
Molecular Plant-Microbe Interactions 13 (4), 374-383
Abstract: The infection process of Colletotrichum lagenarium, the causal agent of cucumber anthracnose disease, involves several key steps: germination; formation of melanized appressoria; appressorial penetration; and subsequent invasive growth in host plants. Here we report that the C. lagenarium CMK1 gene encoding a mitogen-activated protein (MAP) kinase plays a central role in these infection steps. CMK1 can complement appressorium formation of the Pmk1 MAP kinase mutant of Magnaporthe grisea. Deletion of CMK1 causes reduction of conidiation and complete lack of pathogenicity to the host plant. Surprisingly, in contrast to M. grisea pmk1 mutants, conidia of cmk1 mutants fail to germinate on both host plant and glass surfaces, demonstrating that the CMK1 MAP kinase regulates conidial germination. However, addition of yeast extract rescues germination, indicating the presence of a CMK1-independent pathway for regulation of conidial germination. Germinating conidia of cmk1 mutants fail to form appressoria and the mutants are unable to grow invasively in the host plant. This strongly suggests that MAP kinase signaling pathways have general significance for infection structure formation and pathogenic growth in phytopathogenic fungi. Furthermore, three melanin genes show no or slight expression in the cmk1 mutant when conidia fail to germinate, suggesting that CMK1 plays a role in gene expression required for appressorial melanization.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Link to article at publishers website
Database assignments for author(s): Yoshitaka Takano, Kazuyuki Mise, Taisei Kikuchi, Yasuyuki Kubo

Research topic(s) for pests/diseases/weeds:
molecular biology - genes
general biology - morphology - evolution

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Colletotrichum orbiculare