The epithelial sodium channel (ENaC) is intracellularly located as a tetramer - PubMed (original) (raw)
Comparative Study
. 2002 Jul;444(4):549-55.
doi: 10.1007/s00424-002-0855-4. Epub 2002 May 29.
Affiliations
- PMID: 12136275
- DOI: 10.1007/s00424-002-0855-4
Comparative Study
The epithelial sodium channel (ENaC) is intracellularly located as a tetramer
Lisette Dijkink et al. Pflugers Arch. 2002 Jul.
Abstract
The epithelial sodium channel (ENaC) plays an important role in Na(+) homeostasis by determining the Na(+) transport rate in so-called end-organs such as the renal collecting duct, distal colon, salivary and sweat gland ducts. ENaC is formed by heteromultimerization of three homologous subunits, termed alpha, beta, and gamma ENaC. The number of subunits and stoichiometry remain a matter of debate. In this study, sucrose gradient analysis of Xenopus laevis oocytes expressing rENaC revealed that ENaC forms heterotetramers, when the membrane fraction was solubilized in 0.1% (wt/vol) Na-deoxycholate. However, solubilization of the membrane proteins in higher concentrations of detergents dissociated the ENaC subunits of the tetramers in dimers. Co-immunoprecipitation studies with FLAG-tagged ENaC subunits suggest that during dissociation of ENaC tetramers the composition of dimers is completely random. Glycosidase digestion studies show that the ENaC subunits are retarded in the endoplasmic reticulum (ER) and pre-Golgi, whereas only a small fraction is inserted into the plasma membrane. Immunocytochemical analysis confirmed that ENaC is primarily located intracellularly. In addition, these findings are not restricted to the oocyte expression system, since identical results were found in rabbit connecting tubule and cortical collecting duct cells in primary culture and in rabbit colon.
Similar articles
- The heterotetrameric architecture of the epithelial sodium channel (ENaC).
Firsov D, Gautschi I, Merillat AM, Rossier BC, Schild L. Firsov D, et al. EMBO J. 1998 Jan 15;17(2):344-52. doi: 10.1093/emboj/17.2.344. EMBO J. 1998. PMID: 9430626 Free PMC article. - Expression of amiloride-sensitive sodium channel: a strategy for the coexpression of multimeric membrane protein in Sf9 insect cells.
Rao US, Mehdi A, Steimle RE. Rao US, et al. Anal Biochem. 2000 Nov 15;286(2):206-13. doi: 10.1006/abio.2000.4861. Anal Biochem. 2000. PMID: 11067742 - Segmental variability of ENaC subunit expression in rat colon during dietary sodium depletion.
Greig ER, Baker EH, Mathialahan T, Boot-Handford RP, Sandle GI. Greig ER, et al. Pflugers Arch. 2002 Jul;444(4):476-83. doi: 10.1007/s00424-002-0828-7. Epub 2002 Apr 25. Pflugers Arch. 2002. PMID: 12136266 - Insight toward epithelial Na+ channel mechanism revealed by the acid-sensing ion channel 1 structure.
Stockand JD, Staruschenko A, Pochynyuk O, Booth RE, Silverthorn DU. Stockand JD, et al. IUBMB Life. 2008 Sep;60(9):620-8. doi: 10.1002/iub.89. IUBMB Life. 2008. PMID: 18459164 Review. - Biophysical approach to determine the subunit stoichiometry of the epithelial sodium channel using the Xenopus laevis oocyte expression system.
Kosari F, Sheng S, Kleyman TR. Kosari F, et al. Methods Mol Biol. 2006;337:53-63. doi: 10.1385/1-59745-095-2:53. Methods Mol Biol. 2006. PMID: 16929938
Cited by
- Aldosterone-Regulated Sodium Transport and Blood Pressure.
Tsilosani A, Gao C, Zhang W. Tsilosani A, et al. Front Physiol. 2022 Feb 7;13:770375. doi: 10.3389/fphys.2022.770375. eCollection 2022. Front Physiol. 2022. PMID: 35197862 Free PMC article. Review. - DEG/ENaC Ion Channels in the Function of the Nervous System: From Worm to Man.
Bianchi L. Bianchi L. Adv Exp Med Biol. 2021;1349:165-192. doi: 10.1007/978-981-16-4254-8_9. Adv Exp Med Biol. 2021. PMID: 35138615 - Gain-of-Function Mutation W493R in the Epithelial Sodium Channel Allosterically Reconfigures Intersubunit Coupling.
Shobair M, Dagliyan O, Kota P, Dang YL, He H, Stutts MJ, Dokholyan NV. Shobair M, et al. J Biol Chem. 2016 Feb 19;291(8):3682-92. doi: 10.1074/jbc.M115.678052. Epub 2015 Dec 14. J Biol Chem. 2016. PMID: 26668308 Free PMC article. - Expression and purification of the alpha subunit of the epithelial sodium channel, ENaC.
Reddy BG, Dai Q, McNicholas CM, Fuller CM, Kappes JC, DeLucas LJ. Reddy BG, et al. Protein Expr Purif. 2016 Jan;117:67-75. doi: 10.1016/j.pep.2015.09.014. Epub 2015 Sep 21. Protein Expr Purif. 2016. PMID: 26394093 Free PMC article. - The Human Acid-Sensing Ion Channel ASIC1a: Evidence for a Homotetrameric Assembly State at the Cell Surface.
van Bemmelen MX, Huser D, Gautschi I, Schild L. van Bemmelen MX, et al. PLoS One. 2015 Aug 7;10(8):e0135191. doi: 10.1371/journal.pone.0135191. eCollection 2015. PLoS One. 2015. PMID: 26252376 Free PMC article.
Publication types
MeSH terms
Substances
LinkOut - more resources
Full Text Sources
Molecular Biology Databases