Project description:Rab GTPases regulate vesicle trafficking in organisms and play crucial roles in growth and development. Arthrobotrys oligospora is a representative species of nematode-trapping (NT) fungi, it can produce trapping devices for nematode predation. Our previous study found that deletion of Aorab7A abolished the trap formation and sporulation. Here, we investigated the regulatory mechanism of AoRab7A using transcriptomic, biochemical, and phenotypic comparisons. Transcriptome analysis, yeast library screening, and Y2H assays identified two vacuolar protein sorting (Vps) proteins, AoVps41 and AoVps35, as putative targets of AoRab7A. The deletion of Aovps41 and Aovps35 caused considerable defects in multiple phenotypic traits. We further found a close connection between AoRab7A, homotypic fusion, vacuolar protein sorting, and the retromer involved in vesicle-vacuole fusion, which triggered vacuolar fragmentation. Further transcriptome analysis showed that AoRab7A and AoVps35 play essential roles in many cellular processes and components including proteasomes, autophagy, fatty acid degradation, and ribosomes in A. oligospora. Furthermore, we verified that AoRab7A, AoVps41, and AoVps35 are involved in ribosome and proteasome functions. The absence of these proteins inhibited the biosynthesis of nascent proteins and enhanced ubiquitination. Our findings suggest that AoRab7A can interact with AoVps41 and AoVps35 to mediate vacuolar fusion and influence lipid droplet accumulation, autophagy, stress response, and secondary metabolism. These proteins are especially required for the conidiation and trap development of A. oligospora
Project description:We report the transcriptomic comparisions between key processes required for various stages of fungal carnivory in nematode-trapping fungus Arthrobotrys oligospora when induced with nematodes. The reference assembly used for remapping is A. oligospora TWF154 (GenBank assembly accession: GCA_004768765.1)
Project description:We report the transcriptomic comparisions between ku70 control and ste12 mutant strains in nematode-trapping fungus Arthrobotrys oligospora when induced with nematodes. Fungal Ste12 transcription factor and the upstream MAPK cascade are highly conserved and plays a role in host sensing and pathogenesis in various fungal pathogens. Identification of Ste12-dependent in A. oligospora may provide further insights into the molecular mechanisms of nematode-sensing and trap morphogenesis. The reference assemly used for remapping is A. oligospora TWF154 (GenBank assembly accession: GCA_004768765.1)
Project description:Nematode-trapping (NT) fungi can form unique infection structures (traps) to capture and kill free-living nematodes, thus play a potential role in the biocontrol of nematodes. Arthrobotrys oligospora is a representative species of the NT fungi. Here we performed dual RNA-seq to understand the interaction between A. oligospora and Caenorhabditis elegans. We identified 5752 unique differentially expressed genes during trap formation and predation, and the rac gene was significantly upregulated. Alternative splicing events occurred in 896 2012 genes, including the rac and rho2 gene. Further, we characterized three Rho GTPases (Rho2, Rac, and Cdc42) in A. oligospora using gene disruption and multi-phenotypic analysis. The analyses showed that AoRac and AoCdc42 play an important role in mycelium growth, lipid accumulation, DNA damage, sporulation, trap formation, pathogenicity, and stress response in A. oligospora. Furthermore, AoCdc42 and AoRac specifically interacted with components of the Nox complex, thus regulating the production of reactive oxygen species. Furthermore, the transcript levels of several genes associated with the protein kinase A, mitogen-activated protein kinase, and p21-activated kinase were also altered in the mutants, suggesting that Rho GTPases might function upstream of these kinases. This study highlights the important role of Rho GTPases in A. oligospora and provides insights into the regulatory mechanism of signaling pathways in trap morphogenesis and lifestyle transition of NT fungi.
2021-12-24 | GSE192443 | GEO
Project description:Methylation in the nematode-trapping fungus Arthrobotrys oligospora
Project description:ADP-ribosylation factors (Arfs) belong to the small GTPases superfamily and regulate mycelial development, endocytosis, and virulence in fungi. Nematode-trapping (NT) fungi can form unique infection structures (traps) to capture and kill free-living nematodes, thus play a potential role in the biocontrol of nematodes. Arthrobotrys oligospora is a representative species of the NT fungi. Here, the functions of two Arf-GAPs, Age1 (AoAge1) and Age2 (AoAge2) orthologue to S. cerevisiae were identified in A. oligospora by gene knockout and multi-phenotypic analysis. It was found that AoAge1 and AoAge2, especially AoAge2, play an important role in vegetative growth, conidiation, trap formation, DNA damage, endoplasmic reticulum stress, mitochondrial activity, endocytosis, heat shock stress, ROS level, and autophagy of A. oligospora. Importantly, our transcriptomic analysis (12 h) showed that nearly 62.7% of A. oligospora genes (11479) were directly or indirectly regulated by AoAge2, indicating that Arf-GAP plays a global role in the growth and development of A. oli gospora. Revealed by transcriptomic analysis differentially upregulated genes in the absence of Aoage2 were involved in autophagy and carbohydrate, amino acid and sphingolipid metabolism while downregulated genes were involved in longevity regulating pathway and carbohydrate, amino acid and secondary metabolites biosynthesis. In addition, metabolomic analysis showed that many compounds were markedly reduction in ΔAoage2 mutants strain. Our results highlighted that AoAge1 and AoAge2 play a crucial role in the asexual growth, development, differentiation, and lifestyle transition, especially, AoAge2 is indispensable for conidiation and trap morphogenesis of A. oligospora. These results demonstrated crucial roles for AoAge1 and AoAge2 in the fungal growth, environmental adaption and pathogenicity, which provided insights into the function of Arf-GAPs in A. oligospora and other fungi.
Project description:ADP-ribosylation factors (Arfs) belong to the small GTPases superfamily and regulate mycelial development, endocytosis, and virulence in fungi. Nematode-trapping (NT) fungi can form unique infection structures (traps) to capture and kill free-living nematodes, thus play a potential role in the biocontrol of nematodes. Arthrobotrys oligospora is a representative species of the NT fungi. Here, the functions of two Arf-GAPs, Age1 (AoAge1) and Age2 (AoAge2) orthologue to S. cerevisiae were identified in A. oligospora by gene knockout and multi-phenotypic analysis. It was found that AoAge1 and AoAge2, especially AoAge2, play an important role in vegetative growth, conidiation, trap formation, DNA damage, endoplasmic reticulum stress, mitochondrial activity, endocytosis, heat shock stress, ROS level, and autophagy of A. oligospora. Importantly, our transcriptomic analysis (12 h) showed that nearly 62.7% of A. oligospora genes (11479) were directly or indirectly regulated by AoAge2, indicating that Arf-GAP plays a global role in the growth and development of A. oli gospora. Revealed by transcriptomic analysis differentially upregulated genes in the absence of Aoage2 were involved in autophagy and carbohydrate, amino acid and sphingolipid metabolism while downregulated genes were involved in longevity regulating pathway and carbohydrate, amino acid and secondary metabolites biosynthesis. In addition, metabolomic analysis showed that many compounds were markedly reduction in ΔAoage2 mutants strain. Our results highlighted that AoAge1 and AoAge2 play a crucial role in the asexual growth, development, differentiation, and lifestyle transition, especially, AoAge2 is indispensable for conidiation and trap morphogenesis of A. oligospora. These results demonstrated crucial roles for AoAge1 and AoAge2 in the fungal growth, environmental adaption and pathogenicity, which provided insights into the function of Arf-GAPs in A. oligospora and other fungi.