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Updated: Aug 10, 2026

Single-molecule Super-resolution Imaging of Phosphatidylinositol 4,5-bisphosphate in the Plasma Membrane with Novel Fluorescent Probes
07:26

Single-molecule Super-resolution Imaging of Phosphatidylinositol 4,5-bisphosphate in the Plasma Membrane with Novel Fluorescent Probes

Published on: October 15, 2016

GPI-alkaline phosphatase insertion into phosphatidylcholine monolayers: phase behavior and morphology changes

Achraf Kouzayha1, Françoise Besson

  • 1Laboratoire Organisation and Dynamique des Membranes Biologiques, UMR-CNRS 5013, Université Claude Bernard Lyon I, 43 boulevard du 11 novembre 1918, F-69622 Villeurbanne Cedex, France.

Biochemical and Biophysical Research Communications
|June 28, 2005
PubMed

Insights

GPI-anchored proteins interact differently with saturated and unsaturated phospholipids in biomimetic membranes. This study reveals distinct behaviors of GPI-BIAP with DPPC and POPC, impacting membrane organization.

Area of Science:

  • Biochemistry
  • Membrane Biophysics
  • Surface Chemistry

Background:

  • Glycosylphosphatidylinositol (GPI)-anchored proteins reside in plasma membrane microdomains.
  • Understanding GPI-anchor and phospholipid interactions is crucial for membrane biophysics.

Purpose of the Study:

  • To investigate the interaction between a GPI-anchored protein and different phospholipid models.
  • To elucidate how lipid unsaturation affects GPI-protein and lipid interactions within a biomimetic system.

Main Methods:

  • Utilized phosphatidylcholine monolayers at the air-water interface as a biomimetic membrane model.
  • Employed Langmuir isotherms and Brewster Angle Microscopy (BAM) to analyze GPI-BIAP interactions with DPPC and POPC.

Main Results:

  • GPI-BIAP exhibited differential interactions with saturated (DPPC) and unsaturated (POPC) phospholipid monolayers.
  • Despite similar exclusion pressures, Langmuir isotherms and BAM images confirmed distinct interfacial organizations.

Conclusions:

  • The lipidic GPI-anchor's interaction with phospholipids is sensitive to acyl chain saturation.
  • GPI-BIAP incorporation influences membrane organization differently based on lipid composition.

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