Fig. 2

miR-221 Is Required for Vegfc/Flt4 Signaling (A–F) Confocal micrographs Tg(fli1a:egfp)^y1 embryos at 27 hpf; arrowheads denote ISVs; lateral views, dorsal is up, anterior to the left. (A) Embryo injected with 6 ng control MO. (B) Embryo injected with 1 ng flt4 and 5 ng control MO. (C) Embryo injected with 1 ng control and 5 ng miR-221 MO. (D) Embryo injected with 1 ng flt4 MO and 5 ng miR-221 MO. (E) kdrl^um19 mutant embryo injected with 10 ng control MO. (F) kdrl^um19 mutant embryo injected with 10 ng of miR-221 MO. (G) Quantification of ISV length in wild-type or kdrl^um19 mutant embryos injected with indicated MOs. Measurements were made of four adjacent ISVs per embryo in at least 18 embryos from three separate injections; ^-p < 0.001; N.S., not statistically different. (H–K) Tg(fli1a:egfp)^y1 embryos injected with hsp70:vegfc-2A-mcherry transposable element and heat shocked at 15 ss. Red indicates Vegfc-2A-mcherry expression. Arrowheads indicate ectopic formation of vessels. Embryos at 33 hpf coinjected with (H) 10 ng control MO, (I) 2 ng flt4 MO, (J) 10 ng miR-221 MO, or (K) mutant for kdrl^um19. (L) Proportion of hemisegments with ectopic vessel sprouts in embryos injected with 25 pg Tol2-hsp70:vegfc-2A-mcherry and 25 pg Tol2 transposase. Embryos were co-injected with indicated MO, or were mutant for the kdrl^um19 allele as determined by genotyping following phenotypic analysis. ^-p < 0.02; N.S., not significant. Scale bars are (A–F) 50 µm and (H–K) 25 μm.