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Updated: Dec 20, 2025

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

9.9K

Phosphatidylinositol 4,5-bisphosphate is localized in the plasma membrane outer leaflet and regulates cell adhesion

Atsuko Yoneda1, Kaori Kanemaru2, Ai Matsubara1

  • 1Laboratory of Genome and Biosignals, School of Life Sciences, Tokyo University of Pharmacy and Life Sciences, Tokyo, Japan.

Biochemical and Biophysical Research Communications
|May 23, 2020
PubMed

Insights

Phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2) is found on the cell surface, not just inside cells. This outer leaflet PI(4,5)P2 is crucial for cell attachment, spreading, and migration.

Area of Science:

  • Cell Biology
  • Biochemistry
  • Membrane Biology

Background:

  • Phospholipids exhibit asymmetric distribution in mammalian plasma membranes.
  • Phosphatidylinositol (PI) and its phosphorylated forms, including PI(4,5)P2, are typically localized to the inner plasma membrane leaflet.
  • While PI(4,5)P2's inner leaflet functions are well-established, its role in the outer leaflet remains largely unknown.

Purpose of the Study:

  • To investigate the presence and function of PI(4,5)P2 in the outer leaflet of the plasma membrane.
  • To determine the cellular processes regulated by cell surface PI(4,5)P2.

Main Methods:

  • Detection of PI(4,5)P2 on non-permeabilized cells using anti-PI(4,5)P2 antibodies and PLCδ1 PH domain.
  • Analysis of PI(4,5)P2 localization patterns and dependence on cholesterol, sphingomyelin, and actin polymerization.
  • Functional assays assessing cell attachment, spreading, and migration after blocking cell surface PI(4,5)P2.

Main Results:

  • Cell surface PI(4,5)P2 was detected universally across various cell lines and primary mouse cells.
  • The punctate distribution of cell surface PI(4,5)P2 was dependent on cholesterol, sphingomyelin, and actin polymerization.
  • Inhibition of cell surface PI(4,5)P2 significantly impaired cell attachment, spreading, and migration.

Conclusions:

  • PI(4,5)P2 is uniquely localized to the outer leaflet of the plasma membrane.
  • Cell surface PI(4,5)P2 plays a critical role in regulating cell adhesion, morphology, and motility.
  • These findings reveal a novel function for PI(4,5)P2 in cell surface-mediated processes.
Keywords:
AdhesionMigrationOuter leafletPhosphatidylinositol 4,5-bisphosphate (PI(4,5)P(2))PhospholipidsPlasma membrane

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