Trafficking, localization and degradation of the Na⁺,HCO₃^- co-transporter NBCn1 in kidney and breast epithelial cells.

ABSTRACT: The Na+;HCO3^- co-transporter NBCn1 (SLC4A7) is a major regulator of intracellular pH yet its trafficking and turnover are essentially unstudied. Here, we used MDCK-II and MCF-7 cells to investigate these processes in epithelial cells. GFP-NBCn1 membrane localization was abolished by truncation of the full NBCn1 C-terminal tail (C-tail) yet did not require the C-terminal PDZ-binding motif (ETSL). Glutathione-S-Transferase-pulldown of the C-tail followed by mass spectrometry analysis revealed putative interactions with multiple sorting-, degradation- and retention factors, including the scaffolding protein RACK1. Pulldown of FLAG-tagged deletion constructs mapped the RACK1 interaction to the proximal NBCn1 C-tail. Proximity Ligation Assay and co-immunoprecipitation confirmed that

SUBMITTER: Olesen CW 

PROVIDER: S-EPMC5943355 | biostudies-literature | 2018 May

REPOSITORIES: biostudies-literature