pp60(c-src) modulates microvascular endothelial phenotype and in vitro angiogenesis

Area of Science:

• Cell Biology
• Molecular Biology
• Angiogenesis Research

Background:

• The c-src tyrosine kinase is known to associate with the platelet-derived growth factor (PDGF) receptor.
• The precise role of c-src kinase activity in endothelial cell responses to PDGF requires further elucidation.

Purpose of the Study:

• To investigate the regulatory effects of c-src tyrosine kinase on microvascular endothelial cells.
• To determine the impact of c-src overexpression and kinase activity on PDGF signaling and in vitro angiogenesis.

Main Methods:

• Overexpression of wild-type c-src, kinase-negative c-src mutant, and v-src in microvascular endothelial cells.
• Analysis of cell morphology in 2D culture and in vitro angiogenesis in 3D culture.
• Assessment of PDGF-mediated mitogenic effects and tube formation.

Main Results:

• c-src kinase activity was found to inhibit PDGF-induced mitogenic signals.
• Overexpression of c-src proteins altered endothelial cell morphology (shape and size) in 2D culture.
• In 3D culture, c-src overexpression increased tube diameter and reduced branching during angiogenesis.
• Kinase-negative c-src mutants led to abortive tube formation with disconnected multicellular fragments.

Conclusions:

• The c-src tyrosine kinase plays a critical regulatory role in endothelial cell proliferation, size, and cytoskeletal organization.
• c-src kinase activity is essential for the proper formation of a differentiated multicellular network during in vitro angiogenesis.