Molecular mechanism of Oxr1p mediated disassembly of yeast V-ATPase.

ABSTRACT: The eukaryotic vacuolar H⁺-ATPase (V-ATPase) is regulated by reversible disassembly into autoinhibited V₁-ATPase and V_o proton channel subcomplexes. We recently reported that the TLDc protein Oxr1p induces V-ATPase disassembly in vitro. Whether and how Oxr1p is involved in enzyme disassembly in vivo, however, is not known. Here, using yeast genetics and fluorescence microscopy, we show that Oxr1p is essential for efficient V-ATPase disassembly in the cell. Supporting biochemical and biophysical in vitro experiments show that whereas Oxr1p-driven holoenzyme disassembly can occur in the absence of nucleotides, the presence of ATP greatly accelerates the process. ATP hydrolysis is needed, however, for subsequent release of Oxr1p so that the free V₁

SUBMITTER: Khan MM 

PROVIDER: S-EPMC11094088 | biostudies-literature | 2024 May

REPOSITORIES: biostudies-literature