MrPEX33 is involved in infection-related morphogenesis and pathogenicity of Metarhizium robertsii

Peroxin Pex14/17 Is Required for Trap Formation, and Plays Pleiotropic Roles in Mycelial Development, Stress Response, and Secondary Metabolism in Arthrobotrys oligospora

“…In M. oryzae , the loss of PEX14/17 delayed conidial generation and appressorial formation, reduced appressorial turgor accumulation and penetration ability in host plants, and significant decreased fungal virulence; however, PEX14/17 deletion showed no significant difference with regard to colony morphology and aerial hyphal development and only a slight reduction in radial growth ( 21 ). In M. robertsii , the conidial germination, conidiation, and fungal virulence were all greatly reduced upon PEX14/17 depletion, but there were no appreciable changes between colony phenotypes and the colony diameter of the PEX14/17 mutant strains and control strains on various conditions in the vegetative growth assay ( 34 ). In this study, we provide direct evidence that the knockout of PEX14/17 represses conidial production and germination and impairs trap formation and pathogenicity in A. oligospora , which are consistent with previous reports.…”

“…In fungi, besides common functions including the β-oxidation of fatty acids and the detoxification of hydrogen peroxide, peroxisomes are crucial for the metabolism of various unique carbon and nitrogen sources, including oleic acid, methanol, primary amines, and uric acid, and play an important role in response to stress ( 36 , 37 ). Previous evidence has highlighted a decreasing ability for the control of fatty acid utilization, ROS degradation, stress tolerance, and cell wall integrity in fungi without Pex14/17 ( 21 , 34 , 38 ). Our results indicate that the disruption of AoPEX14/17 also resulted in a significant decrease in fatty acid utilization and tolerance to oxidative stress.…”

Functional Analysis of Keto-Acid Reductoisomerase ILVC in the Entomopathogenic Fungus Metarhizium robertsii

“…100-μL aliquots of a conidial suspension collected from strains cultured on SDAY were spread on SDAY at 28 °C in the dark; at 18 h, 48 h, and 96 h, cultured strains were collected. Conidial suspensions were put on cicada ( Cryptotympana atrata Westwood (Hemiptera: Cicadidae)) hind wings [ 19 ]. For the samples of M. robertsii during the infection progress, conidia were used for cuticle infection by dipping the fifth-instar Galleria mellonella L. (Lepidoptera: Pyralidae) larvae into a conidial suspension (1 × 10 7 conidia mL −1 ) for 10 s. Then, the infected larvae were maintained in a stable photoperiod with 16 h of light and 8 h of dark at 28 °C without feeding.…”

Host–Pathogen Interactions between Metarhizium spp. and Locusts

“…This finding indicates that MAPK is required to trigger the differentiation of germlings to the appressorium. The appressorial formation is eliminated by the deficiency of MaMk1 or Pmk1 of M. rileyi , which are FUS3/KSS1-type MAPKs [ 32 , 40 ]. The appressorial formation on locust hindwings is not produced by the mutant of MrSte11 (MAPKKK), MrSte7 (MAPKK), and MrFus3 (MAPK) [ 41 ].…”

“…Appressorial differentiation was delayed by these impaired genes, including the tetraspanin MaPls1 , the pH-responsive transcription factor MapacC , and the O-mannosyltransferases MaPmt2 and MaPmt4 [ 26 , 54 , 55 , 56 ]. The formation rate of appressorium is reduced by some genes mutants including the negative transcription regulators MaNmrA , MaAreB , and β-tubulin of M. acridum , the actin-regulating kinase MrArk , the sucrose non-fermenting protein kinase MaSnf1, the bifunctional catalase and peroxidase MaKatG1 , MrHex1 , which is related to the formation of the woronin body, and MaPEX33 , which is associated with the peroxisomal import pathway, the polyketide synthase MrPks2 [ 29 , 30 , 40 , 45 , 57 , 58 , 59 , 60 , 61 ]. The appressorial formation ability is lost when the transcription factor MrSkn7 is mutated and the inhibition of Isocitrate lyase ManICL is inhibited [ 62 , 63 ].…”