The priming factor CAPS1 regulates dense-core vesicle acidification by interacting with rabconnectin3β/WDR7 in neuroendocrine cells.

ABSTRACT: Vacuolar-type H⁺-ATPases (V-ATPases) contribute to pH regulation and play key roles in secretory and endocytic pathways. Dense-core vesicles (DCVs) in neuroendocrine cells are maintained at an acidic pH, which is part of the electrochemical driving force for neurotransmitter loading and is required for hormonal propeptide processing. Genetic loss of CAPS1 (aka calcium-dependent activator protein for secretion, CADPS), a vesicle-bound priming factor required for DCV exocytosis, dissipates the pH gradient across DCV membranes and reduces neurotransmitter loading. However, the basis for CAPS1 binding to DCVs and for its regulation of vesicle pH has not been determined. Here, MS analysis of CAPS1 immunoprecipitates from brain membrane fractions revealed that CAPS1 associates with a

SUBMITTER: Crummy E 

PROVIDER: S-EPMC6579465 | biostudies-literature | 2019 Jun

REPOSITORIES: biostudies-literature