Musculoskeletal Embryonic Nuclear Protein 1 (MUSTN1)

Mustn1 was originally identified in fracture callus tissue, but its greatest expression is detected in skeletal muscle. Mustn1 is localized to some peripherally located nuclei. Using RNA interference (RNAi), Though silencing Mustn1 mRNA had no effect on myoblast proliferation, it did significantly impair myoblast differentiation, preventing myofusion.Mustn1-silenced myoblasts elongated poorly and were mononucleated. In contrast, control RNAi-treated and parental myoblasts presented as large, multinucleated myotubes. Further supporting the morphological observations, immunocytochemistry of Mustn1-silenced cells demonstrated significant reductions in myogenin (Myog) and myosin heavy chain (Myhc) expression at 4 and 6 days of differentiation as compared with control and parental cells.