Fig. 3

Phenotypes of the tbx5 morphants and IGF-I-treated tbx5 morphants. The WT (a) and MIS groups (b) had normal hearts, and the WTIGF1 (c) group had minimal pericardial effusion. The MO group (d) had string-like hearts accompanied by a massive pericardial edema, but the appearance of hearts in the MOIGF1 group (e) was improved. There were no significant differences observed in the trunks of the WT (f), MIS (g) and WTIGF1 groups (i), in which the trunks were straight and the somites appeared to be “V-shaped”. The trunk of the MO group (h) bent severely and showed a “U shape”. The MOIGF1 group (j) had partially-restored appearances of the trunks and curvatures of somites. The pectoral fins of the MO group (m) were truncated or undeveloped, but the WT (k), MIS (l), WTIGF1 (n), and the MOIGF1 group (o) had normal pectoral fins. The MO group had significantly lower normal morphology rates of the hearts (p), trunks (q) and pectoral fins (r). Compared with the MO group, the MOIGF1 group had significantly higher percentages of normal morphology rates of the hearts (p), trunks (q) and pectoral fins. No defective embryos were found in the WT and MIS group, and almost all of the WTIGF1 group embryos developed well. Red arrow: pericardial effusion; black arrow head: defect site; dashed line: shape of somite border. Data are presented as the means ± standard deviations. ^*P < 0.05 vs. WT; ^#P < 0.05 MOIGF1 vs. MO. WT: wild-type embryos; MO: tbx5 morphants; MIS: mismatch tbx5 morpholino-treated wild-type embryos; WTIGF1: IGF-I-treated wild-type embryos; MOIGF1: IGF-I-treated tbx5 morphants; hpf: hours post-fertilization. The number of specimens was 50, and the number of independent experiments was 3 in each group