Myosin heavy chain isoforms in postnatal muscle development of mice

TLDR

The study used high‑resolution gel electrophoresis to map myosin heavy chain composition in mouse skeletal muscles during postnatal development, aiming to clarify muscle development in transgenic mice and related pathologies. Expression patterns were examined in four hind‑limb muscles, the diaphragm, the tongue, and the masseter. Sequential transitions from embryonic to neonatal to adult myosin isoforms occurred with muscle‑specific timing, including transient adult isoform expression in soleus and tongue, indicating distinct developmental programs across muscles.

Abstract

Abstract In this study, using a high‐resolution gel electrophoresis technique, we have characterized the myosin heavy chain composition in different skeletal muscle of the mouse during postnatal development. The pattern of myosin heavy chain expression was studied in four hind limb muscles, the diaphragm, the tongue and the masseter. All of these muscles displayed the usual sequential transitions from embryonic to neonatal and to adult myosin heavy chain isoforms but more interestingly these transitions occur with a distinct chronology in the different muscles. In addition, our results demonstrated a transitory pattern of expression for certain adult myosin heavy chain isoforms in the soleus and the tongue. In the soleus muscle IIB and in the tongue IIA myosin heavy chain isoforms were detected only for a short time during postnatal life. Our results demonstrate that muscles of the mouse with different functions are subjected to a distinct programs of myosin isoform transitions during postnatal muscle development. This study describes new data which will help us to understand both postnatal muscle development in transgenic mouse muscles as well as in muscle pathology.