Fig. 1

Endothelium-specific knockout of Cdc42 in mice. a Fluorescence indicating Cdc42 expression in the lungs. Cdc42 control (Cdc42^fl/+; Tie2-cre-ER; Td) and Cdc42-KO (Cdc42^fl/fl; Tie2-cre-ER; Td) mice were pulsed with tamoxifen at 4 weeks after birth and harvested 3 weeks later. The Td-tomato (red) model was used to mark pulmonary vascular ECs. The lung sections were immunostained with antibodies against Cdc42 (green) that distributed within ECs (which appear yellow and exhibit overlapping red staining), as well as other types of cells, in control mice; however, Cdc42 was absent from the endothelium and present in the alveolar epithelium in KO mice, n = 4 mice per group. Scale bar, 25 μm. b Representative western blotting results showing that Cdc42 expression differed significantly between control and Cdc42-KO mice. The experiment was repeated three times with similar results. c Density analysis of the western blotting results. **P < 0.01 (Student’s t test)