Dlk1 expression in Dlk1flox and Dlk1cons mice. A) Northern blot of WT and Dlk1flox-pat embryos and placentae at e12.5. B) Quantification of Dlk1flox-pat Northern blot. Dlk1 expression was normalized to β-actin, and the WT level was set to 100%. Error bars denote SEM, n = 3 for each genotype. C) Northern blot of WT and Dlk1cons-pat embryos and placentae at e12.5. D) Quantification of Dlk1cons-pat Northern blot. Dlk1 expression was normalized to β-actin, and the WT level was set to 100%. Error bars denote SEM, n = 6 for each genotype, * denotes p < 0.01.