Figure 1.

Nuclear-localized FOXO1 is detected in angiogenic fronts which is essential for vessel sprouting

(A) Angiogenic proceeding postnatal day-5 mice retina was dissected and immunostained with CD31 for vessel imaging (left). Retinas are divided into three areas; tip, vascular front, and vascular plexus, which are enlarged and assessed for the immunostaining using antibodies for FOXO1 (red), CD31 (white), and ESM1 (green). ESM1 is used as the tip marker. Data are representative of three independent experiments. Bar: 50 μm.

(B) HUVECs formed spheroids and sprouted in the three-dimensional culture. A bright field differential interference contrast (DIC) image was shown on the left. Immunostaining with anti-FOXO1 antibody was shown in green color (middle). Arrows indicated the cells obtaining nuclear-localized FOXO1. Merged images and the high-power view of spout-front (tip-like) regions, representative in a-c, were shown on the right. Bar: 50 μm.

(C) HUVECs spheroids were subjected to sprouting assay for 2 days in the presence of siRNA for control or FOXO1. Bar: 50 μm. The right graph indicates the number of sprouts from at least 5 independent experiments. Data are shown as mean ± S.D. Black dot represents each individual value. ∗p < 0.005 compared with si-Control.

See also Figures S1–S3.