• Duchenne muscular dystrophy (DMD) is a severe, progressive, muscle-wasting disease that leads to difficulties with movement and premature death.
• Duchenne muscular dystrophy (DMD) is caused by mutations in the DMD gene. These mutations frequently entail deletions of one or more exons, which disrupt the open reading frame and introduce a premature stop codon. This leads to the production of a nonfunctional truncated dystrophin protein, resulting in a severe muscle degeneration phenotype.
• The exon 44, exon 45 and exon 46 of mouse Dmd are replaced by exon 44 and exon 46 of human DMD in B-hDMD(exon44-46, del45) mice.
• Mouse DMD protein was only detectable in wild-type C57BL/6JNifdcNifdc mice but not in homozygous B-hDMD(exon44-46, del45) mice. And serum creatine kinase activity was significantly greater in homozygous B-hDMD(exon44-46, del45) mice compared to that in wild-type mice.
• This product is used for pharmacodynamics of Duchenne muscular dystrophy.

Gene targeting strategy for B-hDMD(exon44-46, del45) mice. The exon 44, exon 45 and exon 46 of mouse Dmd are replaced by exon 44 and exon 46 of human DMD in B-hDMD(exon44-46, del45) mice.

Strain specific analysis of DMD mRNA expression in wild-type C57BL/6JNifdc mice and B-hDMD(exon44-46, del45) mice by RT-PCR. Heart and skeletal muscle RNA were isolated from wild-type C57BL/6JNifdc mice (+/+) and homozygous B-hDMD(exon44-46, del45) mice (H/Y), then cDNA libraries were synthesized by reverse transcription, followed by PCR with mouse Dmd primers. The transcripts in homozygous mice are shorter than that in wild-type mice, and the sequences were confirmed via Sanger Sequencing.

Western blot analysis of DMD protein expression in wild-type C57BL/6JNifdc mice and homozygous B-hDMD(exon44-46, del45) mice. Various tissue lysates were collected from wild-type C57BL/6JNifdc mice (+/+) and homozygous B-hDMD(exon44-46, del45) mice (H/Y), and then analyzed by western blot with anti-Dystrophin antibody (Sigma-Aldrich, D8168). 40 μg total proteins were loaded for western blotting analysis. DMD was detected in heart, skeletal muscle, skin and brain, but not in liver and kidney.

Serum creatine kinase activity analysis in wild-type C57BL/6JNifdc mice and homozygous B-hDMD(exon44-46, del45) mice by colorimetric. Serum was collected from wild-type C57BL/6JNifdc mice (+/+, n=3, 6-week old male) and homozygous B-hDMD(exon44-46, del45) mice (H/Y, n=3, 6-week old male). Creatine kinase activity was analyzed by colorimetric in a kinetic mode every 2 min for a total of 36 min at 37℃ (creatine kinase activity assay kit: Abcam, ab155901). OD450 readings were linear between T1 (at time 6) and T2 (12min for WT and homozygous mice). Creatine kinase activity was significantly greater in homozygous B-hDMD(exon44-46, del45) mice compared to that in wild-type mice. Values are expressed as mean ± SEM. Multiple t test, p=0.01.