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Scaling of lipid membrane rigidity with domain area fraction.

ABSTRACT: Biological membranes are highly heterogeneous in composition which in turn leads to local variations in the physical properties. Here we quantify how heterogeneity in stiffness determines the effective bending modulus, κ_eff, of model phase-separated membranes with coexisting soft fluid and rigid gel domains. We find that the temperature- and composition- dependent trends in membrane rigidity collapse onto a single curve, such that κ_eff directly scales with the area fraction of the rigid gel domains. Using no adjustable parameters, the measurements are found to agree with theoretical predictions for inhomogenous membranes and indicate that κ_eff is sensitive to the lateral distribution of the rigid phase within the membrane. This key finding confirms that the properties of heterogeneous membranes can be quantitatively predicted if the area fraction and properties of the individual phases are known.

SUBMITTER: Kelley EG

PROVIDER: S-EPMC8220873 | biostudies-literature | 2019 Apr

REPOSITORIES: biostudies-literature

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Scaling of lipid membrane rigidity with domain area fraction.

Kelley Elizabeth G EG Butler Paul D PD Nagao Michihiro M

Soft matter 20190221 13

Biological membranes are highly heterogeneous in composition which in turn leads to local variations in the physical properties. Here we quantify how heterogeneity in stiffness determines the effective bending modulus, κ<sub>eff</sub>, of model phase-separated membranes with coexisting soft fluid and rigid gel domains. We find that the temperature- and composition- dependent trends in membrane rigidity collapse onto a single curve, such that κ<sub>eff</sub> directly scales with the area fraction ...[more]

PMID: 30789180

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