Early decrease of IIx myosin heavy chain transcripts in Duchenne muscular dystrophy.

M Pedemonte; C Sandri; S Schiaffino; C Minetti

doi:10.1006/bbrc.1999.0213

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PubMed · 10049732

Early decrease of IIx myosin heavy chain transcripts in Duchenne muscular dystrophy.

M Pedemonte·C Sandri·S Schiaffino·C Minetti

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Abstract

We studied by in situ hybridization the expression of IIx myosin heavy chain (MHC) transcripts in Duchenne Muscular Dystrophy (DMD) muscle. In normal muscle fibers IIx MHC transcripts were only expressed in type 2b or very fast fibers. Our results indicate that muscle fibers expressing IIx MHC transcripts disappear early in DMD muscle. This may be due to the transformation of type 2b fibers into type 2a fibers and/or to selective degeneration of the type 2b fibers. The very fast 2b fibers may be subjected to a greater mechanical stress during muscle contraction and dystrophin deficiency may render them more susceptible to mechanical damage.

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Adenosine Triphosphatases Adolescent Age Factors Child Child, Preschool Gene Expression Regulation, Developmental Humans In Situ Hybridization Infant Muscle Fibers, Skeletal Muscular Dystrophies Myosin Heavy Chains Protein Isoforms Staining and Labeling Transcription, Genetic Journal Article Research Support, Non-U.S. Gov't

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M Pedemonte, C Sandri, S Schiaffino, C Minetti. 1999-02-16. Early decrease of IIx myosin heavy chain transcripts in Duchenne muscular dystrophy.. https://doi.org/10.1006/bbrc.1999.0213

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