Apical localization of PMCA2w/b is lipid raft-dependent

Yuning Xiong, Géza Antalffy, Ágnes Enyedi, Emanuel E. Strehler

Research output: Contribution to journalArticle

16 Scopus citations

Abstract

Alternative splicing of the first intracellular loop differentially targets plasma membrane calcium ATPase (PMCA) isoform 2 to the apical or basolateral membrane in MDCK cells. To determine if the targeting is affected by lipid interactions, we stably expressed PMCA2w/b and PMCA2z/b in MDCK cells, and analyzed the PMCA distribution by confocal fluorescence microscopy and membrane fractionation. PMCA2w/b showed clear apical and lateral distribution, whereas PMCA2z/b was mainly localized to the basolateral membrane. A significant fraction of PMCA2w/b partitioned into low-density membranes associated with lipid rafts. Depletion of membrane cholesterol by methyl-β-cyclodextrin resulted in reduced lipid raft association and a striking loss of PMCA2w/b from the apical membrane, whereas the lateral localization of PMCA2z/b remained unchanged. Our data indicate that alternative splicing differentially affects the lipid interactions of PMCA2w/b and PMCA2z/b and that the apical localization of PMCA2w/b is lipid raft-dependent and sensitive to cholesterol depletion.

Original languageEnglish (US)
Pages (from-to)32-36
Number of pages5
JournalBiochemical and Biophysical Research Communications
Volume384
Issue number1
DOIs
StatePublished - Jun 19 2009

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Keywords

  • Alternative splicing
  • Apical membrane
  • Lipid raft
  • Membrane targeting
  • Plasma membrane calcium ATPase
  • PMCA2

ASJC Scopus subject areas

  • Biochemistry
  • Biophysics
  • Cell Biology
  • Molecular Biology

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