Cytoskeleton assembly at endothelial cell-cell contacts is regulated by alphaII-spectrin-VASP complexes

TY - JOUR

T1 - Cytoskeleton assembly at endothelial cell-cell contacts is regulated by alphaII-spectrin-VASP complexes

AU - Benz, Peter M

AU - Blume, Constanze

AU - Moebius, Jan

AU - Oschatz, Chris

AU - Schuh, Kai

AU - Sickmann, Albert

AU - Walter, Ulrich

AU - Feller, Stephan M

AU - Renné, Thomas

PY - 2008/1/14

Y1 - 2008/1/14

N2 - Directed cortical actin assembly is the driving force for intercellular adhesion. Regulated by phosphorylation, vasodilator-stimulated phosphoprotein (VASP) participates in actin fiber formation. We screened for endothelial proteins, which bind to VASP, dependent on its phosphorylation status. Differential proteomics identified alphaII-spectrin as such a VASP-interacting protein. alphaII-Spectrin binds to the VASP triple GP(5)-motif via its SH3 domain. cAMP-dependent protein kinase-mediated VASP phosphorylation at Ser157 inhibits alphaII-spectrin-VASP binding. VASP is dephosphorylated upon formation of cell-cell contacts and in confluent, but not in sparse cells, alphaII-spectrin colocalizes with nonphosphorylated VASP at cell-cell junctions. Ectopic expression of the alphaII-spectrin SH3 domain at cell-cell contacts translocates VASP, initiates cortical actin cytoskeleton formation, stabilizes cell-cell contacts, and decreases endothelial permeability. Conversely, the permeability of VASP-deficient endothelial cells (ECs) and microvessels of VASP-null mice increases. Reconstitution of VASP-deficient ECs rescues barrier function, whereas alphaII-spectrin binding-deficient VASP mutants fail to restore elevated permeability. We propose that alphaII-spectrin-VASP complexes regulate cortical actin cytoskeleton assembly with implications for vascular permeability.

AB - Directed cortical actin assembly is the driving force for intercellular adhesion. Regulated by phosphorylation, vasodilator-stimulated phosphoprotein (VASP) participates in actin fiber formation. We screened for endothelial proteins, which bind to VASP, dependent on its phosphorylation status. Differential proteomics identified alphaII-spectrin as such a VASP-interacting protein. alphaII-Spectrin binds to the VASP triple GP(5)-motif via its SH3 domain. cAMP-dependent protein kinase-mediated VASP phosphorylation at Ser157 inhibits alphaII-spectrin-VASP binding. VASP is dephosphorylated upon formation of cell-cell contacts and in confluent, but not in sparse cells, alphaII-spectrin colocalizes with nonphosphorylated VASP at cell-cell junctions. Ectopic expression of the alphaII-spectrin SH3 domain at cell-cell contacts translocates VASP, initiates cortical actin cytoskeleton formation, stabilizes cell-cell contacts, and decreases endothelial permeability. Conversely, the permeability of VASP-deficient endothelial cells (ECs) and microvessels of VASP-null mice increases. Reconstitution of VASP-deficient ECs rescues barrier function, whereas alphaII-spectrin binding-deficient VASP mutants fail to restore elevated permeability. We propose that alphaII-spectrin-VASP complexes regulate cortical actin cytoskeleton assembly with implications for vascular permeability.

KW - Actin Cytoskeleton

KW - Amino Acid Sequence

KW - Animals

KW - Binding Sites

KW - Carrier Proteins

KW - Cell Adhesion

KW - Cell Adhesion Molecules

KW - Endothelial Cells

KW - Intercellular Junctions

KW - Mice

KW - Microfilament Proteins

KW - Molecular Sequence Data

KW - Phosphoproteins

KW - Phosphorylation

KW - Protein Interaction Domains and Motifs

KW - Protein Interaction Mapping

U2 - 10.1083/jcb.200709181

DO - 10.1083/jcb.200709181

M3 - SCORING: Journal article

C2 - 18195108

VL - 180

SP - 205

EP - 219

JO - J CELL BIOL

JF - J CELL BIOL

SN - 0021-9525

IS - 1

ER -