Fig. 3

Fig. 3 miR-126 Regulates Vascular Integrity and Lumen Maintenance In Vivo

(A) miR-126 and miR-126^* enrichment (qRT-PCR) in GFP⁺ endothelial cells from 72 hpf Tg(flk1:GFP)^s843 zebrafish compared to GFP^- cells.

(B) Relative levels of miR-126 and miR-126^* in 72 hpf zebrafish embryos.

(C) miR-126 expression monitored by qRT-PCR during zebrafish development.

(D) Levels of miR-126/126^* or egfl7 (across intron containing miR-126) quantified by qRT-PCR in 72 hpf zebrafish injected with miR-126 MOs relative to control.

(E) Lateral views of control and miR-126 MO-injected Tg(flk1:GFP)^s843; Tg(gata1:dsRed)^sd2 zebrafish (72 hpf). Brightfield microscopy (top) revealed no major changes in gross morphology, while flk1:GFP showed normal blood vessel patterning (middle). Presence of blood cells (gata1:dsRed) in the intersomitic vessels (isv), dorsal aorta (da) and primary cardinal vein (pcv) was greatly reduced in morphants (bottom). y, yolksac; h, head; ht, heart.

(F) miR-126 morphants (48 hpf) had normal vessel patterning (flk1:GFP), but developed cranial hemorrhages (gata1:dsRed; arrow) in the head. baa, branchial arch arteries.

(G) Ventral view of baa suggested smaller luminal size in miR-126 morphants.

(H) Transverse section of control or miR-126 MO-treated zebrafish revealed that the da and pcv of morphants had a smaller lumen than controls; higher magnification (right panels) of boxed area shows collapsed da and small pcv in morphants. flk1:GFP, green; ZO-1, an epithelial marker, red.