PREFERENTIAL SUBSARCOLEMMAL LOCALIZATION OF DYSTROPHIN AND BETA-DYSTROGLYCAN MESSENGER-RNA IN HUMAN SKELETAL-MUSCLES

The intracellular localization of dystrophin and beta-dystroglycan mRN A in skeletal muscles of patients with Duchenne muscular dystrophy (DM D) or Becker muscular dystrophy (BMD) and normal subjects were examine d by in situ hybridization using biotinylated oligonucleotide probes. These mRNAs were found preferentially in sarcolemma in the skeletal mu scles of both normal subjects and affected patients. Quantitative anal ysis of mRNA signals demonstrated no prominent reduction dystrophin or beta-dystroglycan mRNA in DMD/BMD muscles. These results suggest that even mRNAs with deletions contain specific information that affects t heir localization, and the characteristic defect of dystrophin in DMD/ BMD muscles seems to be caused mainly by the instability of dystrophin protein, as a post-transcriptional event.