Figure 4: Transgenic expression of Atp2a1 rescues Ebf3-dependent respiratory failure.
From: Ebf factors and MyoD cooperate to regulate muscle relaxation via Atp2a1
(a) Ebf3-mutant animals were crossed to Atp2a1-transgenic mice and frequencies of Ebf3 wild-type and mutant genotypes on an Atp2a1 wild-type or transgenic background are shown before and after birth; E18.5: n=115, D0.5: n=231. (b) Comparison of compound Ebf3-mutant and Atp2a1-transgenic animals as indicated shortly after birth. Note the cyanotic appearance only in Ebf3−/−/Atp2a1wt mice; Ebf3−/−/Atp2a1tg mice can be detected 12 h after birth. Length is indicated in centimetres. (c) Determination of sarcomere length in the diaphragm of Ebf3+/+/Atp2a1tg and Ebf3−/−/Atp2a1tg newborn mice. n=3; error bars=s.d. (d,e) Single twitch stimulation (50 V, 1 ms) of diaphragm muscle from newborn mice of the indicated genotypes. (d) Measurement of single twitch normalized to the cross-sectional area, representing muscle force in response to the stimulation. (e) Total duration of muscle contraction after single twitch stimulation. n=3; error bars=s.d. (f) Transgenic expression of Atp2a1 in Ebf3-mutant animals does not allow prolonged survival. Survival of animals of the indicated genotypes is followed over time and plotted against days; n= 3 to 5 each. (g) Impaired weight gain in Ebf3-deficient, Serca1 transgenic mice. Animals of the indicated genotypes were weighed every 24 h, and weight is plotted against age of the mice; n=4 to 5 each; error bars=s.d.
