Figure 4. ARRB1 is required for VEGF-C/VEGFR3 signaling.
(a) Representative immunoblot demonstrating loss of VEGF-C-induced VEGFR3 activation in HMVEC-L cells transfected with ARRB1 siRNAs (U: untreated and unstarved.) Quantitation of VEGF-C-induced phosphorylation of (b) VEGFR3, (c-d) Akt, (e) eNOS, and (f) Erk phosphorylation. No significant difference was observed in (f). Data represents mean ± SEM of at least 3 independent experiments. Statistical analysis was performed using two-way ANOVA and Tukey's multiple comparisons test. (g) Overexpression of adenoviral vectors expressing a constitutively active Akt (myr)) or GFP in HMVEC-L. (h) Representative image demonstrating partial rescue of HMVEC-L tube formation by constitutively active Akt, with quantification (i). Representative images are shown. Data represents mean ± SEM of at least 3 independent experiments. Statistical analysis was performed using one-way ANOVA and Tukey's multiple comparisons test. *, p < 0.05; **, p < 0.01; ***, p < 0.001.