LonP1 regulates mitochondrial network remodeling through the PINK1/Parkin pathway during myoblast differentiation.

Myoblast differentiation is a crucial process for myogenesis. Mitochondria function as an energy-providing machine that is critical to this process, and mitochondrial dysfunction can prevent myoblasts from fusing into myotubes. However, the molecular mechanisms underlying the dynamic regulation of mitochondrial networks remain poorly understood. In the present study, we found that the PTEN induced kinase 1 (PINK1)/Parkin (an E3 ubiquitin-protein ligase) pathway is activated at the early stage of myoblast differentiation. Moreover, downregulation of mitofusin 2 (Mfn2) and increased dynamin-related protein 1 (Drp1) resulted in loosely formed mitochondria during this period. Furthermore, selective knockdown of the mitochondrial matrix protein Lon peptidase-1 (LonP1) at the early stage of myoblast differentiation induced mitochondrial depolarization and suppressed the PINK1/Parkin pathway and reduced Mfn2 and Drp1 levels, which blocked mitochondrial remodeling and myoblast differentiation. Overall, these data demonstrate that LonP1 promotes myoblast differentiation by regulating PINK1/Parkin-mediated mitochondrial remodeling.