title: Subconfluent endothelial cells form podosomes downstream of cytokine and RhoGTPase signaling.
abstract: Adhesion, migration and invasion of endothelial cells are prerequisites for the formation of blood vessels and have to be controlled on a subcellular level. We report that subconfluent human umbilical vein endothelial cells (HUVEC) are able to constitutively form podosomal adhesions that are sites of matrix metalloprotease concentration and matrix degradation. Importantly, incubation of serum-starved cells with VEGF or TNFalpha revealed the dependence of podosomes on cytokine signaling. Podosome formation was also stimulated by addition of monocytes to HUVEC. Microinjection/application of specific inhibitors or active/inactive mutants showed that regulatory pathways include Src kinase and RhoGTPase signaling, N-WASP activation and Arp2/3 complex-dependent actin nucleation. In sum, our data show that HUVEC displaying a migratory phenotype constitutively form f-actin-rich adhesions with podosomal characteristics downstream of cytokine signaling. We propose that HUVEC podosomes play an important role in endothelial cell migration and invasion.
authors.affiliation: Institut für Prophylaxe und Epidemiologie der Kreislaufkrankheiten, Ludwig-Maximilians-Universität, Pettenkoferstr. 9, 80336 München, Germany.
authors.forename: Anna-Eleonor
authors.initials: AE
authors.lastname: Osiak
authors.forename: Gerhardt
authors.initials: G
authors.lastname: Zenner
authors.forename: Stefan
authors.initials: S
authors.lastname: Linder
mesh_terms: D051377:Actin-Related Protein 2; D051378:Actin-Related Protein 3; D000199:Actins / Q000378:metabolism; D001427:Bacterial Toxins / Q000494:pharmacology; D001792:Blood Platelets / Q000502:physiology; D002448:Cell Adhesion / Q000502:physiology; D002450:Cell Communication / Q000502:physiology; D002452:Cell Count; D022081:Cell Surface Extensions / Q000187:drug effects / Q000378:metabolism*; D002478:Cells, Cultured; D018920:Coculture Techniques; D016895:Culture Media, Serum-Free / Q000494:pharmacology; D016207:Cytokines / Q000494:pharmacology / Q000502:physiology*; D003598:Cytoskeletal Proteins / Q000378:metabolism; D042783:Endothelial Cells / Q000166:cytology* / Q000378:metabolism / Q000502:physiology; D029968:Escherichia coli Proteins / Q000494:pharmacology; D005109:Extracellular Matrix / Q000378:metabolism; D006801:Humans; D020782:Matrix Metalloproteinases / Q000378:metabolism; D008845:Microinjections; D008856:Microscopy, Fluorescence; D009000:Monocytes / Q000502:physiology; D015846:Monokines / Q000494:pharmacology; D009154:Mutation / Q000235:genetics; D009419:Nerve Tissue Proteins / Q000494:pharmacology; D019000:Phosphotyrosine / Q000378:metabolism; D015398:Signal Transduction / Q000502:physiology*; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology; D042461:Vascular Endothelial Growth Factor A / Q000494:pharmacology; D051317:Wiskott-Aldrich Syndrome Protein, Neuronal; D020741:rho GTP-Binding Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000502:physiology*; D019061:src-Family Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism
chemical_list: C495926:ACTR2 protein, human; C495928:ACTR3 protein, human; D051377:Actin-Related Protein 2; D051378:Actin-Related Protein 3; D000199:Actins; D001427:Bacterial Toxins; D016895:Culture Media, Serum-Free; D016207:Cytokines; D003598:Cytoskeletal Proteins; D029968:Escherichia coli Proteins; D015846:Monokines; D009419:Nerve Tissue Proteins; D014409:Tumor Necrosis Factor-alpha; D042461:Vascular Endothelial Growth Factor A; C495771:WASL protein, human; D051317:Wiskott-Aldrich Syndrome Protein, Neuronal; C060296:cytotoxic necrotizing factor type 1; D019000:Phosphotyrosine; D019061:src-Family Kinases; D020782:Matrix Metalloproteinases; D020741:rho GTP-Binding Proteins