Requirement of a mitogen-activated protein kinase for appressorium formation and penetration of insect cuticle by the entomopathogenic fungus Beauveria bassiana.

ABSTRACT: Beauveria bassiana is an important insect-pathogenic fungus that invades insects by direct penetration of the host cuticle. To delineate the molecular mechanisms involved in fungal infection, a mitogen-activated protein kinase (MAPK) gene, Bbmpk1, which encodes a YERK1 family MAPK was isolated and characterized. Targeted gene disruption of Bbmpk1 resulted in a complete loss of virulence when applied topically to host insects but did not affect growth of the fungus when conidia were injected directly into the hemocoel. Hyphae of the mutant strain growing in the insect hemocoel were unable to penetrate the cuticle growing outwards and consequently failed to sporulate on the cadaver surface. These data suggest that BbMPK1 is essential for penetration of the insect cuticle both from the outsid

SUBMITTER: Zhang Y 

PROVIDER: S-EPMC2849248 | biostudies-literature | 2010 Apr

REPOSITORIES: biostudies-literature