Regulation of ENaC expression at the cell surface by Rab11. Biochem Biophys Res Commun 2008 Dec 12;377(2):521-525
Date
10/18/2008Pubmed ID
18926797Pubmed Central ID
PMC2612579DOI
10.1016/j.bbrc.2008.10.014Scopus ID
2-s2.0-55649109395 (requires institutional sign-in at Scopus site) 38 CitationsAbstract
The epithelial Na(+) channel (ENaC) is an essential channel responsible for Na(+) reabsorption. Coexpression of Rab11a and Rab3a small G proteins with ENaC results in a significant increase in channel activity. In contrast, coexpression of Rab5, Rab27a, and Arf-1 had no effect or slightly decreased ENaC activity. Inhibition of MEK with PD98059, Rho-kinase with Y27632 or PI3-kinase with LY294002 had no effect on ENaC activity in Rab11a-transfected CHO cells. Fluorescence imaging methods demonstrate that Rab11a colocalized with ENaC. Rab11a increases ENaC activity in an additive manner with dominant-negative dynamin, which is a GTPase responsible for endocytosis. Brefeldin A, an inhibitor of intracellular protein translocation, blocked the stimulatory action of Rab11a on ENaC activity. We conclude that ENaC channels, present on the apical plasma membrane, are being exchanged with channels from the intracellular pool in a Rab11-dependent manner.
Author List
Karpushev AV, Levchenko V, Pavlov TS, Lam V, Vinnakota KC, Vandewalle A, Wakatsuki T, Staruschenko AMESH terms used to index this publication - Major topics in bold
AnimalsCHO Cells
Cell Membrane
Cricetinae
Cricetulus
Epithelial Sodium Channels
Mice
Transfection
rab GTP-Binding Proteins
rab3A GTP-Binding Protein
