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Updated: Jul 19, 2025
08:15
Membrane Remodeling of Giant Vesicles in Response to Localized Calcium Ion Gradients
Published on: July 16, 2018
8.0K
Model of membrane deformations driven by a surface pH gradient
Toni V Mendes1,2, Jonas Ranft3, Hélène Berthoumieux2,4
1Laboratoire Ondes et Matière d'Aquitaine, Université de Bordeaux, Unité Mixte de Recherche 5798, CNRS, F-33400 Talence, France.
Physical Review. E
|August 16, 2023
Summary
This study models how cellular organelle shapes, like mitochondria cristae, change due to internal biochemical processes. It reveals how pH gradients influence membrane composition and shape, impacting organelle function.
Area of Science:
- Biophysics
- Cell Biology
- Biochemistry
Background:
- Cellular organelle shape is linked to metabolic state.
- Mechanisms coupling biochemical pathways and membrane geometry are under investigation.
Purpose of the Study:
- To model the coupling between lipid composition and membrane geometry.
- To investigate the deformation of mitochondria cristae under a pH gradient.
Main Methods:
- Utilized a generalized Helfrich free energy model.
- Derived stress tensor and Green's function for tubular membranes.
- Computed phase diagrams for induced deformations.
Main Results:
- Developed a model linking lipid composition, membrane geometry, and deformation.
- Applied the model to mitochondria cristae with a pH gradient.
- Predicted tube deformations consistent with observed cristae shape changes.
Conclusions:
- pH gradients can alter membrane lipid composition (e.g., cardiolipins).
- This alteration drives specific membrane deformations in organelles like mitochondria.
- The model provides insights into organelle shape regulation and function.
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