Expression and alternative splicing of N-RAP during mouse skeletal muscle development

Cell Motil Cytoskeleton. 2008 Dec;65(12):945-54. doi: 10.1002/cm.20317.

Abstract

N-RAP alternative splicing and protein localization were studied in developing skeletal muscle tissue from pre- and postnatal mice and in fusing primary myotubes in culture. Messages encoding N-RAP-s and N-RAP-c, the predominant isoforms of N-RAP detected in adult skeletal muscle and heart, respectively, were present in a 5:1 ratio in skeletal muscle isolated from E16.5 embryos. N-RAP-s mRNA levels increased three-fold over the first 3 weeks of postnatal development, while N-RAP-c mRNA levels remained low. N-RAP alternative splicing during myotube differentiation in culture was similar to the pattern observed in embryonic and neonatal muscle, with N-RAP-s expression increasing and N-RAP-c mRNA levels remaining low. In both developing skeletal muscle and cultured myotubes, N-RAP protein was primarily associated with developing myofibrillar structures containing alpha-actinin, but was not present in mature myofibrils. The results establish that N-RAP-s is the predominant spliced form of N-RAP present throughout skeletal muscle development.

Publication types

  • Research Support, N.I.H., Intramural
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Actinin / metabolism
  • Alternative Splicing*
  • Animals
  • Cells, Cultured
  • Exons / genetics
  • Gene Expression
  • Gene Expression Regulation, Developmental*
  • Mice
  • Muscle Development / genetics*
  • Muscle Proteins / genetics*
  • Muscle Proteins / metabolism
  • Myofibrils / genetics
  • Myofibrils / metabolism*
  • Protein Isoforms / genetics
  • Protein Isoforms / metabolism

Substances

  • Muscle Proteins
  • Nrap protein, mouse
  • Protein Isoforms
  • Actinin