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Dynamin-related protein AoVps1 mediating mitochondrial fission in complex with AoMdv1 is necessary for mitochondrial morphology, mitophagy, conidiation, trap formation, and energy metabolism of Arthrobotrys oligospora

ABSTRACT: Mitochondrial fission is critical for organelle homeostasis and cellular differentiation. Here, we functionally characterized the mitochondrial fission-related proteins AoMdv1 and AoVps1 in the nematode-trapping fungus Arthrobotrys oligospora. Deletion of Aomdv1 or Aovps1 completely arrested mitochondrial division, generating hyperfused, giant mitochondria. Multi-omics and phenotypic analysis revealed that this disruption precipitates a systemic cellular collapse, characterized by severe oxidative stress, elevated apoptosis, and a severe metabolic bottleneck that forces unconsumable carbon flux into extreme lipid droplet hypertrophy. Crucially, our study reveals a previously unrecognized dual function for the dynamin-like protein AoVps1. Beyond interacting with the adaptor AoMdv1 to execute mitochondrial fission, AoVps1 physically binds the core autophagic effectors AoAtg8 and AoAtg20 to directly coordinate macroautophagy and selective mitophagy, respectively. Given that targeted disruption of these autophagic pathways perfectly phenocopies the severe developmental defects of the fission mutants-including abolished conidiation and trap morphogenesis-we define a novel “fission-autophagy” regulatory axis. Collectively, our findings demonstrate that AoVps1 acts as an indispensable molecular bridge, intimately coupling mitochondrial dynamics with autophagic flux to drive the morphological and pathogenic lifestyle transitions in predatory fungi.

ORGANISM(S): Orbilia oligospora

PROVIDER: GSE322740 | GEO | 2026/03/20

REPOSITORIES: GEO

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