Fig. 3

s1pr1 overexpression significantly affects the expression of cardiac precursors and some cardiac regulators. One cell stage embryos were microinjected with 200 ng of the CDS mRNA of s1pr1 or RFP. (A) 48 h after microinjection 20–30 hearts for each experiment were dissected as described in Materials and Methods section. Total RNA was extracted, reverse-transcribed and Q-RT PCR performed. Data were normalized using ef1α as internal standard and are relative to values of hearts from RFP injected embryos. Three different experiments starting from 3 different clutches were used for this analysis.*P < 0.05, **P < 0.001. (B,C) cmlc2 (B) and vmhc (C) ISH were performed on 20 (A) and 25 (B) somite stage embryos. Left side, examples of ISH: double head arrows indicate the extension of the hybridization signals. Scale bar = 100 μm. Right side shows the quantifications of the hybridization signals: the arrow lengths in μm are reported. About 40 embryos were analyzed for each experiment. ****P < 0.0001.