Aggregation of endosomal-vacuolar compartments in the Aovps24-deleted strain in the filamentous fungus Aspergillus oryzae.

Previously, we found that deletion of Aovps24, an ortholog of Saccharomyces cerevisiae VPS24, that encodes an ESCRT (endosomal sorting complex required for transport)-III component required for late endosomal function results in fragmented and aggregated vacuoles. Although defective late endosomal function is likely responsible for this phenotype, critical lack of our knowledge on late endosomes in filamentous fungi prevented us from further characterization. In this study, we identified late endosomes of Aspergillus oryzae, by expressing a series of fusion proteins of fluorescent proteins with orthologs of late endosomal proteins.

Aovps24, a homologue of VPS24, is required for vacuolar formation which could maintain proper growth and development in the filamentous fungus Aspergillus oryzae.

Vps24 (vacuolar protein sorting) is a component of ESCRT III (endosomal sorting complex required for transport), which is required for the formation of MVB (multivesicular body). We have isolated the VPS24 homologue gene, Aovps24, from the filamentous fungus Aspergillus oryzae, and analyzed the localization of AoVps24 using EGFP. AoVps24 was localized in the cytoplasm and late endosome-like structures.