Fig. 3. ZBP-89 rescues the hematopoietic but not the vascular phenotype in
clo-/- mutant zebrafish embryos. (A,B)
Wild-type whole-mount 3 dpf embryos stained with DAF and examined at 4 x
(A) and 10 x (B) magnification, showing blood cells in the heart (red
arrow), the dorsal aorta (arrow, B) and the posterior cardinal vein
(arrowhead, B). (C,D) Clo-/- embryo examined
at at 4 x (C) and 10 x (D) magnification. No extravascular or
circulating blood is seen. Red arrow in C indicates the dilated bloodless
heart. (E,F) ZBP-89 sense RNA injected into
clo-/- embryos, shown at two different magnifications.
Blood formation in the trunk is evident (arrow in F), but the heart chamber
remains dilated and devoid of erythrocytes (E), consistent with the absence of
blood vessels. (G,H) Gata1-driven GFP in clo-/-
48 hpf embryos transgenic (Tg) for gata-1:EGFP, before (G) and
after (H) overexpression of ZBP-89. Gata1 is found in
the GFP-labeled erythroid lineage (arrow in H) in the anterior ICM of
clo-/- embryos overexpressing ZBP-89.
(I-K) Tg (Flk1:EGFP) 48 hpf embryos showing fluorescence in
the axial (arrow in I) and intersomitic (short arrow in I) blood vessels;
fluorescence in the yolk extension is nonspecific. (J,K) flk1-driven
GFP in clo-/- 48 hpf embryos transgenic for
flk1:EGFP before (J) and after (K) overexpression of ZBP-89.
Arrows show a lack of blood vessel formation in both cases. (L)
ZBP-89 expression profile in two different 18 hpf wild-type (WT1 and
WT2) and clo-/- (clo-/-1 and
clo-/-2) embryos, assessed using RT-PCR. GAPDH
expression was examined simultaneously as a reference.