Fig. 6.

MST1 activation governs to promote nuclear import of FOXO1 under hypoxia. a–c Images and comparisons of the nuclear enrichment of FOXO1 in siCont-ECs and siMST1-ECs exposed to normoxia or hypoxia (1% O₂) in the absence (−) or presence (+) of VEGF (200 ng/ml) for 30 min (n = 3, each group). Scale bars, 20 μm. Data represent mean (bar) ± s.d. (error bars). P values, normoxia with VEGF versus hypoxia with VEGF by one-way ANOVA with Tukey’s post hoc test. NS not significant. d Immunoblot analyses of indicated proteins in nuclear and cytoplasmic fractions of HUVECs exposed to normoxia (−) or hypoxia (1% O₂) (+) without (−) or with (+ ) VEGF stimulation (200 ng/ml, 30 min). e Images and comparisons of the nuclear enrichment of GFP in HEK293T cells transfected with gene constructs encoding either GFP-tagged FOXO1 (FOXO1-WT or WT) or non-phosphorylatable FOXO1 (FOXO1-S212A or S212A) together with either control vector (CTL) or gene construct encoding MST1 (FLAG-MST1 or MST1) [n = 161(CTL/WT), 164(MST1/WT), 151(CTL/S212A), 154(MST1/S212A)]. Scale bars, 10 μm. Data represent mean (bar) ± s.d. (error bars). P values, CTL/WT versus MST1/WT or CTL/S212A versus MST1/S212A by one-way ANOVA with Tukey’s post hoc test. NS not significant. f Images of subcellular localizations of FOXO1 in CD31⁺ retinal vessels of WT and Mst1^i∆EC mice at P6. Note that the nuclear enriched FOXO1 at tip ECs (yellow arrowheads) is impaired in Mst1^i∆EC mice, while the distributions of FOXO1 at vascular front and plexus are unaltered. Scale bars, 50 μm. Source data are provided as a Source Data file