Model of pH sensing and regulation in A. nidulans. Black circles denote sites of protein-protein interaction, as does the overlap of two protein domains. The dotted lines of the closed conformation of PacC illustrate non-covalent interaction protecting the proteasome cleavage site. Vps32 is a part of the ESCRT-III complex that recruits to the endosome. The figure is adapted from reference  with information added from references [40, 41, 45, 64].