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Ena/VASP is required for endothelial barrier function in vivo.

ABSTRACT: Enabled/vasodilator-stimulated phosphoprotein (Ena/VASP) proteins are key actin regulators that localize at regions of dynamic actin remodeling, including cellular protrusions and cell-cell and cell-matrix junctions. Several studies have suggested that Ena/VASP proteins are involved in the formation and function of cellular junctions. Here, we establish the importance of Ena/VASP in endothelial junctions in vivo by analysis of Ena/VASP-deficient animals. In the absence of Ena/VASP, the vasculature exhibits patterning defects and lacks structural integrity, leading to edema, hemorrhaging, and late stage embryonic lethality. In endothelial cells, we find that Ena/VASP activity is required for normal F-actin content, actomyosin contractility, and proper response to shear stress. These findings demonstrate that Ena/VASP is critical for actin cytoskeleton remodeling events involved in the maintenance of functional endothelia.

SUBMITTER: Furman C

PROVIDER: S-EPMC2080895 | biostudies-other | 2007 Nov

REPOSITORIES: biostudies-other

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Ena/VASP is required for endothelial barrier function in vivo.

Furman Craig C Sieminski Alisha L AL Kwiatkowski Adam V AV Rubinson Douglas A DA Vasile Eliza E Bronson Roderick T RT Fässler Reinhard R Gertler Frank B FB

The Journal of cell biology 20071112 4

Enabled/vasodilator-stimulated phosphoprotein (Ena/VASP) proteins are key actin regulators that localize at regions of dynamic actin remodeling, including cellular protrusions and cell-cell and cell-matrix junctions. Several studies have suggested that Ena/VASP proteins are involved in the formation and function of cellular junctions. Here, we establish the importance of Ena/VASP in endothelial junctions in vivo by analysis of Ena/VASP-deficient animals. In the absence of Ena/VASP, the vasculatu ...[more]

PMID: 17998398

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