Analysis of dystrophin in muscular diseases by two-dimensional gel electrophoresis using agarose gels in the first dimension

We analyzed dystrophin in cases of normal control, Duchenne muscular dystrophy (DMD), Becker muscular dystrophy (BMD) and infectious muscular disease using two-dimensional gel electrophoresis and immunoblotting with 3 monoclonal dystrophin antibodies : Dys L a mid-rod-domain antibody ; Dys 2, a C-terminal-domain antibody ; and Dys 3, an N-terminal-domain antibody. In cases of normal control, a clearly separated doublet of bands was observed for Dys 1 and 3 at molecular weights 400 and 420 kDa. The isoelectric point was between pH ∼ 5.7-∼ 5.9, similar to that for the myosin heavy chain. In one DMD case, a single faint band was observed for Dys 2. BMD presented a single-band pattern for each antibody. Infectious diseases cases showed 3- to 5-band patterns for Dys 1 and single or no bands for Dys 2 and 3. The pI of the Dys 1 band was almost identical. These results suggest coexistence of normal dystrophin and its proteolytic products, both containing triple helical segment, and show that two-dimensional gel electrophoresis may be applicable in the analysis of dystrophin in muscular disease.