Oxr1 and Ncoa7 regulate V-ATPase to achieve optimal pH for glycosylation within the Golgi apparatus and trans-Golgi network.

ABSTRACT: Maintenance of pH within membranous organelles is crucial for cellular processes such as posttranslational modifications, ligand-receptor interactions, and proteostasis. The precise mechanisms that determine the luminal pH of each organelle are not fully understood. This study investigated the mechanisms that regulate luminal pH to ensure optimal enzymatic activity. We identified Oxr1 and its paralog Ncoa7, which regulate the vacuolar-type proton pump ATPase (V-ATPase) at the Golgi apparatus and trans-Golgi network (TGN). Oxr1 and Ncoa7 were predominantly localized at the Golgi and TGN membranes, dependent on their binding to various GTP-bound Rab proteins. In vitro experiments using purified recombinant proteins indicated that Oxr1 and Ncoa7 directly bind to the catalytic subunit of V-ATP

SUBMITTER: Yoshimura SI 

PROVIDER: S-EPMC12146697 | biostudies-literature | 2025 Jun

REPOSITORIES: biostudies-literature