Ectopic expression of Gas1 does not change endothelial cell growth. (A) Western blot analysis of Gas1 expression. Equal amounts of extracts of murine VE-cadherin–null and VE-cadherin–positive endothelial cells transfected or not with Gas1 cDNA were studied. Cells were seeded at the same density and cultured in the presence of 10% FCS for 3 days before extraction. In cells overexpressing Gas1 the protein was detectable at the right molecular weight. Western blot of γ-tubulin was used as control. (B) Effect of overexpression of Gas1 on endothelial cell proliferation. Growth curves of VE-cadherin–null (▵ and ▴) and VE-cadherin–positive cells (○ and •), overexpressing (▵ and ○) or not overexpressing (▴ and •) Gas1 cDNA. The growth curves were performed as described in “Materials and methods” and data are means of 2 experiments performed in triplicate.