Figure 1

Expression of exogenous rae28 in Rous sarcoma virus (RSV)-rae28 and β-myosin heavy chain (βMHC)-rae28. A, Expression of rae28 was detected in 9.5-dpc embryos by means of whole-mount in situ hybridization analysis. Wt = Wild type; rae28^−/− = Homozygous rae28-deficient embryo; RSV&rae28−/−, RSV-rae28/rae28^−/−; βMHC&rae28−/−, βMHC-rae28/rae28^−/−. Since rae28 expression was hardly detectable in rae28^−/− embryos by means of in situ hybridization, detected rae28 expression can be assured to correspond to exogenous rae28 expression derived from the transgenes. Scale bar, 500 μm. B, Northern blot analysis of 6-month-old βMHC-rae28. Total cellular RNAs were extracted from each of the organs and subjected to Northern blot analysis. GAPDH expression is shown to determine the amount of RNAs on the filter. W = Wild type; T = βMHC-rae28; B = Brain; Thy = Thymus; H = Heart; SM = Skeletal muscle; K = Kidney; Li = Liver; Tes = Testis; S = Spleen; U = Uterus. The sizes of the detected bands are shown on the right side of the panels. Heart-specific expression derived from the βMHC-rae28 transgene was clearly detected, whereas weak expression was also detectable in the skeletal muscle. Note that endogenous rae28 expression was undetectable in adult tissues except for the testis. C, Western blot analysis of the heart. The hearts were removed from 17.5-dpc embryos and from 6-month-old mice and subjected to Western blot analysis with a polyclonal antibody against rae28 protein. Two bands with molecular weight of 125 and 120 kDa were detected in βMHC-rae28 hearts. These bands were compatible with those in 13.5-dpc whole embryos as shown in the figure. We detected rae28 in the wild-type heart by overexposure (not shown). Wt = Wild type; M = Month.