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Updated: Oct 18, 2025
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Single-molecule Super-resolution Imaging of Phosphatidylinositol 4,5-bisphosphate in the Plasma Membrane with Novel Fluorescent Probes
Published on: October 15, 2016
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Intercalate or invaginate: PI(3,4,5)P3 governs a membrane constriction switch in cell shaping
Gabriel Baonza1, Gonzalo Herranz1, Fernando Martin-Belmonte1
1Program of Tissue and Organ Homeostasis, Centro de Biologia Molecular "Severo Ochoa," CSIC-UAM, Madrid 28049, Spain.
Developmental Cell
|September 28, 2021
Summary
Phosphatidylinositol (3,4,5)-trisphosphate) (PI(3,4,5)P3) regulates the Sbf/RabGEF-Rab35 ratcheting mechanism at cell surfaces. This discovery sheds light on how cellular contractions are initiated and controlled.
Area of Science:
- Cell Biology
- Molecular Biology
- Biochemistry
Background:
- Contractile processes are essential for various biological events, including tissue development and cell movement.
- Ratcheting mechanisms drive these cellular contractions, but their surface engagement remains poorly understood.
Purpose of the Study:
- To investigate the regulators of ratcheting engagement at specific cell surfaces.
- To elucidate the role of phosphatidylinositol (3,4,5)-trisphosphate (PI(3,4,5)P3) in cellular contraction.
Main Methods:
- The study utilized advanced cell imaging and biochemical assays.
- Investigated the interaction between PI(3,4,5)P3 and the Sbf/RabGEF-Rab35 complex.
Main Results:
- Demonstrated that PI(3,4,5)P3 is a critical regulator of the Sbf/RabGEF-Rab35 ratcheting mechanism.
- Showed that PI(3,4,5)P3 is essential for initiating ratcheting at the cell surface.
Conclusions:
- PI(3,4,5)P3 plays a paramount role in controlling cellular contractility by engaging specific ratcheting machinery.
- Findings provide new insights into the molecular mechanisms governing cell surface dynamics and tissue morphogenesis.
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