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FBAR syndapin 1 recognizes and stabilizes highly curved tubular membranes in a concentration dependent manner.

ABSTRACT: Syndapin 1 FBAR, a member of the Bin-amphiphysin-Rvs (BAR) domain protein family, is known to induce membrane curvature and is an essential component in biological processes like endocytosis and formation and growth of neurites. We quantify the curvature sensing of FBAR on reconstituted porcine brain lipid vesicles and show that it senses membrane curvature at low density whereas it induces and reinforces tube stiffness at higher density. FBAR strongly up-concentrates on the high curvature tubes pulled out of Giant Unilamellar lipid Vesicles (GUVs), this sorting behavior is strongly amplified at low protein densities. Interestingly, FBAR from syndapin 1 has a large affinity for tubular membranes with curvatures larger than its own intrinsic concave curvature. Finally, we studied the effect of FBAR on membrane relaxation kinetics with high temporal resolution and found that the protein increases relaxation time of the tube holding force in a density-dependent fashion.

SUBMITTER: Ramesh P

PROVIDER: S-EPMC3610093 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

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FBAR syndapin 1 recognizes and stabilizes highly curved tubular membranes in a concentration dependent manner.

Ramesh Pradeep P Baroji Younes F YF Reihani S Nader S SN Stamou Dimitrios D Oddershede Lene B LB Bendix Poul Martin PM

Scientific reports 20130101

Syndapin 1 FBAR, a member of the Bin-amphiphysin-Rvs (BAR) domain protein family, is known to induce membrane curvature and is an essential component in biological processes like endocytosis and formation and growth of neurites. We quantify the curvature sensing of FBAR on reconstituted porcine brain lipid vesicles and show that it senses membrane curvature at low density whereas it induces and reinforces tube stiffness at higher density. FBAR strongly up-concentrates on the high curvature tubes ...[more]

PMID: 23535634

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FBAR syndapin 1 recognizes and stabilizes highly curved tubular membranes in a concentration dependent manner.

Publications

FBAR syndapin 1 recognizes and stabilizes highly curved tubular membranes in a concentration dependent manner.

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