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Updated: May 22, 2026
06:26
Pulling Membrane Nanotubes from Giant Unilamellar Vesicles
Published on: December 7, 2017
Bleb expansion requires transient membrane invaginations that sequester curvature-preferring proteins
Yuki Maekawa1, Saori R Yoshii2, Noboru Mizushima2,3
1Department of Biochemistry, Kyushu University Graduate School of Medical Sciences, Fukuoka 812-8582, Japan.
Summary
Cell migration involves membrane reshaping. Researchers discovered a new structure, the sub-bleb invagination (SBI), that sorts membrane proteins during bleb expansion, impacting cell movement.
Area of Science:
- Cell Biology
- Biophysics
- Membrane Dynamics
Background:
- Cell migration is crucial for biological processes.
- Bleb-based migration involves rapid plasma membrane (PM) expansion.
- Mechanisms of PM reorganization and protein sorting during blebbing are not fully understood.
Purpose of the Study:
- To investigate the role of membrane curvature in protein localization during bleb expansion.
- To identify novel membrane structures involved in bleb-based cell migration.
Main Methods:
- Live-cell imaging techniques.
- Observation of de novo membrane structure formation.
- Analysis of integral membrane protein dynamics.
Main Results:
- A novel inward membrane structure, the sub-bleb invagination (SBI), was identified at the bleb base.
- SBIs exhibit positive curvature and transiently sequester curvature-preferring proteins like Caveolin-1 and Piezo1.
- Overexpression of these proteins inhibited bleb expansion and caused aberrant SBI formation.
Conclusions:
- Bleb expansion involves dynamic redistribution of membrane curvature and protein localization.
- A curvature-based mechanism for membrane protein sorting during blebbing was revealed.
- The interplay between membrane curvature and protein organization influences PM dynamics during cell migration.
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