Structure and function of a vimentin-associated matrix adhesion in endothelial cells
M Gonzales1, B Weksler, D Tsuruta
1Department of Cell and Molecular Biology, Northwestern University Medical School, Chicago, Illinois 60611, USA.
Molecular Biology of the Cell
|February 13, 2001
Summary
Researchers identified a novel endothelial cell adhesion involving alpha4 laminin and alphavbeta3 integrin. This interaction is crucial for endothelial cell branching and wound repair, suggesting a role in new blood vessel formation (angiogenesis).
Area of Science:
- Cell Biology
- Biochemistry
- Angiogenesis Research
Background:
- Endothelial cells form basement membranes containing laminin subunits, crucial for cell adhesion and tissue structure.
- Integrins, like alphavbeta3, are key cell surface receptors mediating cell-matrix and cell-cell interactions.
Purpose of the Study:
- To investigate the function of the alpha4 laminin subunit and alphavbeta3 integrin in endothelial cell adhesion and behavior.
- To characterize the role of this specific endothelial cell-matrix adhesion in cellular processes like morphogenesis and migration.
Main Methods:
- Utilized antibodies against alpha4 laminin (2A3), alphavbeta3 integrin, vinculin, and plectin to identify and localize adhesion structures.
- Assessed endothelial cell (TrHBMECs, HMVECs) adherence to alpha4 laminin G domain.
- Investigated the impact of blocking antibodies on endothelial cell branching morphogenesis and in vitro wound repopulation.
Main Results:
- Identified focal contact-like structures in endothelial cells positive for alpha4 laminin and alphavbeta3 integrin.
- Demonstrated alphavbeta3 integrin-dependent adherence of endothelial cells to the alpha4 laminin G domain.
- Observed interactions of vimentin intermediate filaments and microfilament bundles with these focal contacts.
- Showed that antibodies against alpha4 laminin and alphavbeta3 integrin inhibit endothelial cell branching and wound healing.
Conclusions:
- Characterized a novel endothelial cell-matrix adhesion complex involving alpha4 laminin and alphavbeta3 integrin, regulated by growth factors.
- This adhesion structure exhibits complex cytoskeletal interactions and plays a significant role in endothelial cell morphogenesis and migration.
- The findings suggest a potential role for this adhesion complex in angiogenesis.
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