title: Damage control: cellular mechanisms of plasma membrane repair.
abstract: When wounded, eukaryotic cells reseal in a few seconds. Ca(2+) influx induces exocytosis of lysosomes, a process previously thought to promote repair by 'patching' wounds. New evidence suggests that resealing involves direct wound removal. Exocytosis of lysosomal acid sphingomyelinase (ASM) triggers endocytosis of lesions followed by intracellular degradation. Characterization of injury-induced endosomes revealed a role for caveolae, sphingolipid-enriched plasma membrane invaginations that internalize toxin pores and are abundant in mechanically stressed cells. These findings provide a novel mechanistic explanation for the muscle pathology associated with mutations in caveolar proteins. Membrane remodeling by the ESCRT complex was also recently shown to participate in small-wound repair, emphasizing that cell resealing involves previously unrecognized mechanisms for lesion removal that are distinct from the patch model.
authors.affiliation: Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD 20742-5815, USA. Electronic address: andrewsn@umd.edu.
authors.forename: Norma W
authors.initials: NW
authors.lastname: Andrews
authors.affiliation: Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD 20742-5815, USA; Department of Biology, Federal University of Juiz de Fora, Juiz de Fora, Minas Gerais, Brazil.
authors.forename: Patricia E
authors.initials: PE
authors.lastname: Almeida
authors.affiliation: Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD 20742-5815, USA.
authors.forename: Matthias
authors.initials: M
authors.lastname: Corrotte
mesh_terms: D020013:Calcium Signaling / Q000235:genetics; D021941:Caveolae / Q000378:metabolism*; D002462:Cell Membrane / Q000235:genetics / Q000378:metabolism*; D056827:Endosomal Sorting Complexes Required for Transport / Q000235:genetics; D056890:Eukaryota / Q000235:genetics / Q000378:metabolism; D005089:Exocytosis / Q000235:genetics; D008247:Lysosomes / Q000235:genetics / Q000378:metabolism; D013108:Sphingomyelin Phosphodiesterase / Q000235:genetics / Q000378:metabolism; D014945:Wound Healing / Q000235:genetics*
chemical_list: D056827:Endosomal Sorting Complexes Required for Transport; D013108:Sphingomyelin Phosphodiesterase
keywords: caveolae; endocytosis; injury; muscular dystrophy; resealing