Deletion of integrin linked kinase in endothelial cells results in defective RTK signaling caused by caveolin 1 mislocalization

Publikationen: Beitrag in FachzeitschriftZeitschriftenaufsätzeForschung

AutorInnen

  • Daniela Malan
  • Andrea Elischer
  • Michael Hesse
  • Sara A Wickström
  • Bernd K Fleischmann
  • Wilhelm Bloch

Forschungseinrichtungen

Details

Integrin linked kinase (ILK) connects the ILK-Pinch-Parvin complex with integrin adhesion sites. Because of the functional relevance of integrin-linked signaling for endothelial cell (EC) biology, we have explored this pathway in Ilk(-/-) embryonic stem (ES) cells differentiated into ECs and vessel-like structures. We have focused in particular on the mechanistic relevance of ILK-Pinch-Parvin complex-related signaling for EC development and tube formation. Our analysis revealed that the formation of vessel-like structures was strongly reduced in Ilk(-/-) ES cells and that this phenotype could be rescued by re-expression of ILK in ES cells. ECs were MACS sorted from wild-type (WT) and Ilk(-/-) ES cells and functional analysis using intracellular calcium imaging as the read-out yielded a complete lack of vascular endothelial growth factor- and epidermal growth factor-dependent responses. The possibility of a caveolin 1-related defect was investigated by transfecting WT and Ilk(-/-) ECs with a caveolin 1-EGFP fusion protein. Time-lapse microscopy showed that the prominent phenotype is due to altered dynamics of caveolin 1 and to a lack of positioning of caveolin 1 in the vicinity of the plasma membrane and that it is rescued by re-expressing ILK in the Ilk(-/-) ES cells. We also found that the defect is caused by the perturbed organization of microtubules and cortical actin filaments. Thus, ILK is required as a scaffold to allow actin-microtubule interactions and correct positioning of caveolin 1 close to the plasma membrane. This is crucial for signaling compartmentalization in ECs and explains the key role of ILK for EC development and function.

OriginalspracheEnglisch
ZeitschriftDevelopment (Cambridge, England)
Jahrgang140
Heft5
Seiten (von - bis)987-995
Seitenumfang9
DOIs
PublikationsstatusVeröffentlicht - 01.03.2013

ID: 67758

DOI

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