Knocking myogenin into myf-5 locus, myf5 [myg-ki]

Fig. 1

Line 1. Myf5 locus with 3 exons shown as black boxes

Line 2. linearized myf5 knock-in vector myf5[myg-ki]

Line 3. the structure of the targeted myf5 locus

Line 4. mutant myf5[myg-ki] locus after Cre-mediated deletion

RT-PCR analysis of expression

Fig. 2

RT-PCR analysis of muscle-specific gene expression in early mouse embryos.

a. RT-PCR of myf5 (+/+), myfa5 (+/myg-ki) and myf5 (myg-ki/myg-ki) embryos. Primers measured expression of the indicated transcripts, myf-5, the myogenin knock-in allele at the myf5 locus, or RPL7, ribosomal protein L7.

b. RT-PCR of myf5 (+/myg-ki) embryos at days 8.0, 8.5, and 9.5 dpc.

c. RT-PCR of myf5 (-/-) and myf5 (myg-ki/myg-ki) embryos at 9.5 dpc. PCR products were electrophoresed, blotted, and probed with specific probes.

Newborn mouse skeletons, showing that myogenin knock-in rescues Myf5 rib defect

Fig. 3

Staining of newborn mouse skeletons with Alizarin red and Alcian blue. Lateral views of whole mouse skeletons to show bone (red) and cartilage (blue). The skeleton on the left is from wild-type, the middle skeleton is from myf-5-null mouse and shows the rib cage defect, and the right skeleton is from a Myf5[myg-ki/myg-ki] mouse and shows rescue of the rib cage defect, which was seen in every myf5[myg-ki/myg-ki] mouse analysed.

Nature 379:823 (1996) Wang…Jaenisch