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Fig. 3
Bmp stimulates β-catenin transcriptional activity in ECs to regulate CV formation. (A) Confocal fluorescence images of 48hpf control (no additional Tg) and Tg(hsp70l:dkk1-FLAG) embryos with the Tg(fli1:Gal4db-TΔC-2A-mC);(UAS:GFP);(fli1:Myr-mC) background heat shocked at 24hpf for 1h. (B) Fluorescence intensity of GFP in the CV and CVP, as observed in A, relative to that in control embryos. Data are mean±s.e.m. Control, n=7; Tg(hsp70l:dkk1-FLAG), n=9. (C) Confocal stack fluorescence images of 36hpf embryos injected without (control) or with hsp70l:noggin3-FLAG or hsp70l:bmp2b-FLAG plasmid and heat shocked at 24hpf for 1h, as in A. Transverse sections at the arrows are shown to the right. Arrowheads indicate ectopic venous vessels originating from the CVP. Asterisks indicate CA. (D) Fluorescence intensities of GFP in the CVP of control and hsp70l:noggin3-FLAG-injected embryos, as observed in C, relative to that in control embryos. Data are mean±s.e.m. Control, n=6; hsp70l:noggin3-FLAG, n=8. (E) Confocal images of 32hpf Tg(fli1:Gal4FF);(UAS:NLS-GFP) embryos injected without (control) or with hsp70l:noggin3-FLAG plasmid, heat shocked at 24hpf and subjected to TUNEL staining, as in Fig. 2G. (F) Percentage of TUNEL-positive cells among NLS-GFP-expressing ECs in the CVP of the control and hsp70l:noggin3-FLAG-injected embryos as observed in E. Data are mean±s.e.m. Control, n=15; hsp70l:noggin3-FLAG, n=15. (B,D,F) **P<0.01, ***P<0.001; n.s., not significant. Scale bars: 50µm.