title: Annexin-A5 assembled into two-dimensional arrays promotes cell membrane repair.
abstract: Eukaryotic cells possess a universal repair machinery that ensures rapid resealing of plasma membrane disruptions. Before resealing, the torn membrane is submitted to considerable tension, which functions to expand the disruption. Here we show that annexin-A5 (AnxA5), a protein that self-assembles into two-dimensional (2D) arrays on membranes upon Ca(2+) activation, promotes membrane repair. Compared with wild-type mouse perivascular cells, AnxA5-null cells exhibit a severe membrane repair defect. Membrane repair in AnxA5-null cells is rescued by addition of AnxA5, which binds exclusively to disrupted membrane areas. In contrast, an AnxA5 mutant that lacks the ability of forming 2D arrays is unable to promote membrane repair. We propose that AnxA5 participates in a previously unrecognized step of the membrane repair process: triggered by the local influx of Ca(2+), AnxA5 proteins bind to torn membrane edges and form a 2D array, which prevents wound expansion and promotes membrane resealing.
authors.affiliation: Molecular Imaging and NanoBioTechnology, IECB, UMR-5248 CBMN CNRS-University Bordeaux1-ENITAB, Talence F-33402, France.
authors.forename: Anthony
authors.initials: A
authors.lastname: Bouter
authors.forename: Céline
authors.initials: C
authors.lastname: Gounou
authors.forename: Rémi
authors.initials: R
authors.lastname: Bérat
authors.forename: Sisareuth
authors.initials: S
authors.lastname: Tan
authors.forename: Bernard
authors.initials: B
authors.lastname: Gallois
authors.forename: Thierry
authors.initials: T
authors.lastname: Granier
authors.forename: Béatrice Langlois
authors.initials: BL
authors.lastname: d'Estaintot
authors.forename: Ernst
authors.initials: E
authors.lastname: Pöschl
authors.forename: Bent
authors.initials: B
authors.lastname: Brachvogel
authors.forename: Alain R
authors.initials: AR
authors.lastname: Brisson
mesh_terms: D000818:Animals; D017304:Annexin A5 / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D002118:Calcium / Q000378:metabolism; D002462:Cell Membrane / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D051379:Mice; D018345:Mice, Knockout; D014945:Wound Healing
chemical_list: D017304:Annexin A5; D002118:Calcium