title: An ezrin-rich, rigid uropod-like structure directs movement of amoeboid blebbing cells.
abstract: Melanoma cells can switch between an elongated mesenchymal-type and a rounded amoeboid-type migration mode. The rounded 'amoeboid' form of cell movement is driven by actomyosin contractility resulting in membrane blebbing. Unlike elongated A375 melanoma cells, rounded A375 cells do not display any obvious morphological front-back polarisation, although polarisation is thought to be a prerequisite for cell movement. We show that blebbing A375 cells are polarised, with ezrin (a linker between the plasma membrane and actin cytoskeleton), F-actin, myosin light chain, plasma membrane, phosphatidylinositol (4,5)-bisphosphate and β1-integrin accumulating at the cell rear in a uropod-like structure. This structure does not have the typical protruding shape of classical leukocyte uropods, but, as for those structures, it is regulated by protein kinase C. We show that the ezrin-rich uropod-like structure (ERULS) is an inherent feature of polarised A375 cells and not a consequence of cell migration, and is necessary for cell invasion. Furthermore, we demonstrate that membrane blebbing is reduced at this site, leading to a model in which the rigid ezrin-containing structure determines the direction of a moving cell through localised inhibition of membrane blebbing.
authors: Institute of Cancer Research, Cancer Research UK, Cancer Research UK Tumour Cell Signalling Unit, 237 Fulham Road, London SW3 6JB, UK.
authors: Anna
authors: A
authors: Lorentzen
authors: Jeffrey
authors: J
authors: Bamber
authors: Amine
authors: A
authors: Sadok
authors: Ilan
authors: I
authors: Elson-Schwab
authors: Christopher J
authors: CJ
authors: Marshall
mesh_terms: D045744:Cell Line, Tumor; D002462:Cell Membrane / Q000235:genetics / Q000378:metabolism*; D002465:Cell Movement; D016764:Cell Polarity; D002477:Cells / Q000166:cytology* / Q000378:metabolism; D003598:Cytoskeletal Proteins / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D008545:Melanoma / Q000235:genetics / Q000378:metabolism / Q000503:physiopathology*; D000099149:Ezrin
chemical_list: D003598:Cytoskeletal Proteins; D000099149:Ezrin