Fig. 1

Regulation of MEK1 transgene and ERK1/2 expression. a Activation of the HA-tagged human aMEK1 is regulated by the expression of tTA and doxycycline (DOX) in the TAMEK/MH DTg mouse heart. b At 12.5 dpc, fetal hearts expressed the aMEK1 transgene when the pregnant females did not receive DOX in their drinking water. Expression of aMEK1 transgene was absent in the fetal brain. c At 14.5 dpc, the expression of aMEK1 transgene. And corresponding ERK1/2 phosphorylation, is higher in the atria than in the ventricles as demonstrated in paired tissues (n = 5). d Quantitation of MEK1/2, ERK1/2 and P-ERK1/2 protein from water- (W) or DOX- (D) treated mice at 12.5 dpc, and from ventricular (V) and atrial (A) tissue at 14.5 dpc. Original blots available in Additional file 5 S5