MrArk1, an actin-regulating kinase gene, is required for endocytosis and involved in sustaining conidiation capacity and virulence in Metarhizium robertsii.
Actin-regulating kinase (Ark) plays an important role in controlling endocytosis, which has been shown to be involved in the development and virulence of several fungal pathogens. However, it remains unclear whether Ark1 is required for the development and pathogenicity of an entomopathogenic fungus. Here, MrArk1 (MAA_03415), a homologue of yeast Ark1, was characterized in the insect pathogenic fungus, Metarhizium robertsii. Disruption of MrArk1 led to defects in endocytosis and a marked reduction (58%) in conidiation capacity. The reduced conidiation level was accompanied by repression of several key conidiation-related genes, including brlA, abaA, and wetA. Additionally, the deletion mutant showed a significant decrease in its tolerance to heat shock, but not to UV-B irradiation. Bioassays demonstrated attenuated virulence for the deletion mutant against Galleria mellonella via normal cuticle infection, accompanied by suppressed appressorium formation and reduced transcript levels of several genes involved in cuticle penetration. Taken together, our results indicate that MrArk1 is involved in the heat tolerance, sporulation, and virulence of M. robertsii, and thus is an important factor for sustaining the fungal potential against insect pests.
['Wang|Zhangxun|Z|', 'Jiang|Yuanyuan|Y|', 'Li|Yuandong|Y|', 'Feng|Jianyu|J|', 'Huang|Bo|B|http://orcid.org/0000-0002-3171-2567']
D000818:Animals D001681:Biological Assay D004705:Endocytosis D005656:Fungal Proteins D015966:Gene Expression Regulation, Fungal D005800:Genes, Fungal D016547:Kinesins D007915:Lepidoptera D052981:Metarhizium D009154:Mutation D017346:Protein Serine-Threonine Kinases D013172:Spores, Fungal D014774:Virulence
Actin-regulating kinase Virulence Metarhizium robertsii Appressorium Heat tolerance Sporulation