Minimum-energy vesicle and cell shapes calculated using spherical harmonics parameterization
- 21 January 2011
- journal article
- research article
- Published by Royal Society of Chemistry (RSC) in Soft Matter
- Vol. 7 (5) , 2138-2143
Abstract
An important open question in biophysics is to understand how mechanical forces shape membrane-bounded cells and their organelles. A general solution to this problem is to calculate the bending energy of an arbitrarily shaped membrane surface, which can include both lipids and cytoskeletal proteins, and minimize the energy subject to all mechanical constraints. However, the calculations are difficult to perform, especially for shapes that do not possess axial symmetry. We show that the spherical harmonics parameterization (SHP) provides an analytic description of shape that can be used to quickly and reliably calculate minimum energy shapes of both symmetric and asymmetric surfaces. Using this method, we probe the entire set of shapes predicted by the bilayer couple model, unifying work based on different computational approaches, and providing additional details of the transitions between different shape classes. In addition, we present new minimum-energy morphologies based on non-linear models of membrane skeletal elasticity that closely mimic extreme shapes of red blood cells. The SHP thus provides a versatile shape description that can be used to investigate forces that shape cells.Keywords
This publication has 34 references indexed in Scilit:
- Stomatocyte–discocyte–echinocyte sequence of the human red blood cell: Evidence for the bilayer– couple hypothesis from membrane mechanicsProceedings of the National Academy of Sciences, 2002
- Echinocyte Shapes: Bending, Stretching, and Shear Determine Spicule Shape and SpacingBiophysical Journal, 2002
- Membrane skeleton and red blood cell vesiculation at low pHBiochimica et Biophysica Acta (BBA) - Biomembranes, 1998
- Configurations of fluid membranes and vesiclesAdvances in Physics, 1997
- The conformation of membranesNature, 1991
- Membrane bending energy and shape determination of phospholipid vesicles and red blood cellsEuropean Biophysics Journal, 1989
- Bending Resistance and Chemically Induced Moments in Membrane BilayersBiophysical Journal, 1974
- Biological Membranes as Bilayer Couples. A Molecular Mechanism of Drug-Erythrocyte InteractionsProceedings of the National Academy of Sciences, 1974
- Elastic Properties of Lipid Bilayers: Theory and Possible ExperimentsZeitschrift für Naturforschung C, 1973
- The minimum energy of bending as a possible explanation of the biconcave shape of the human red blood cellJournal of Theoretical Biology, 1970