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The Energy of COPI for Budding Membranes.

ABSTRACT: As a major actor of cellular trafficking, COPI coat proteins assemble on membranes and locally bend them to bud 60 nm-size coated particles. Budding requires the energy of the coat assembly to overcome the one necessary to deform the membrane which primarily depends on the bending modulus and surface tension, ?. Using a COPI-induced oil nanodroplet formation approach, we modulated the budding of nanodroplets using various amounts and types of surfactant. We found a Heaviside-like dependence between the budding efficiency and ?: budding was only dependent on ? and occurred beneath 1.3 mN/m. With the sole contribution of ? to the membrane deformation energy, we assessed that COPI supplies ~1500 kBT for budding particles from membranes, which is consistent with common membrane deformation energies. Our results highlight how a simple remodeling of the composition of membranes could mechanically modulate budding in cells.

SUBMITTER: Thiam AR

PROVIDER: S-EPMC4517886 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature

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The Energy of COPI for Budding Membranes.

Thiam Abdou Rachid AR Pincet Frédéric F

PloS one 20150728 7

As a major actor of cellular trafficking, COPI coat proteins assemble on membranes and locally bend them to bud 60 nm-size coated particles. Budding requires the energy of the coat assembly to overcome the one necessary to deform the membrane which primarily depends on the bending modulus and surface tension, γ. Using a COPI-induced oil nanodroplet formation approach, we modulated the budding of nanodroplets using various amounts and types of surfactant. We found a Heaviside-like dependence betw ...[more]

PMID: 26218078

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