title: Periplakin-dependent re-organisation of keratin cytoskeleton and loss of collective migration in keratin-8-downregulated epithelial sheets.
abstract: Collective migration of epithelial sheets requires maintenance of cell-cell junctions and co-ordination of the movement of the migrating front. We have investigated the role of keratin intermediate filaments and periplakin, a cytoskeletal linker protein, in the migration of simple epithelial cells. Scratch wounding induces bundling of keratins into a cable of tightly packed filaments adjacent to the free wound edge. Keratin re-organisation is preceded by a re-distribution of periplakin away from the free wound edge. Periplakin participates with dynamic changes in the keratin cytoskeleton via its C-terminal linker domain that co-localises with okadaic-acid-treated keratin granules. Stable expression of the periplakin C-terminal domain increases keratin bundling and Ser431 keratin phosphorylation at wound edge resulting in a delay in wound closure. Ablation of periplakin by siRNA inhibits keratin cable formation and impairs wound closure. Knockdown of keratin 8 with siRNA results in (1) a loss of desmoplakin localisation at cell borders, (2) a failure of MCF-7 epithelial sheets to migrate as a collective unit and (3) accelerated wound closure in vimentin-positive HeLa and Panc-1 cell lines. Thus, keratin 8 is required for the maintenance of epithelial integrity during migration and periplakin participates in the re-organisation of keratins in migrating cells.
authors.affiliation: Centre for Stem Cell Research and Regenerative Medicine, School of Biological and Biomedical Sciences, University of Durham, Durham, DH1 3LE, UK.
authors.forename: Heather A
authors.initials: HA
authors.lastname: Long
authors.forename: Veronika
authors.initials: V
authors.lastname: Boczonadi
authors.forename: Lorna
authors.initials: L
authors.lastname: McInroy
authors.forename: Martin
authors.initials: M
authors.lastname: Goldberg
authors.forename: Arto
authors.initials: A
authors.lastname: Määttä
mesh_terms: D045744:Cell Line, Tumor; D002465:Cell Movement / Q000235:genetics / Q000502:physiology; D003598:Cytoskeletal Proteins / Q000235:genetics / Q000378:metabolism; D003599:Cytoskeleton / Q000378:metabolism* / Q000648:ultrastructure; D004847:Epithelial Cells / Q000166:cytology / Q000378:metabolism* / Q000648:ultrastructure; D006367:HeLa Cells; D006801:Humans; D015151:Immunoblotting; D007382:Intermediate Filaments / Q000378:metabolism / Q000648:ultrastructure; D053533:Keratin-8 / Q000235:genetics / Q000378:metabolism*; D007633:Keratins / Q000235:genetics / Q000378:metabolism; D008855:Microscopy, Electron, Scanning; D051179:Plakins / Q000235:genetics / Q000378:metabolism*; D034622:RNA Interference
chemical_list: D003598:Cytoskeletal Proteins; D053533:Keratin-8; D051179:Plakins; D007633:Keratins