NUDT7 Can Promote Slow Myofiber Formation and Its Endogenous Expression

Skeletal muscle is a tissue mainly composed of four types of myofibers. They are formed of mult-inucleated myotubes through myogenic differentiation. Myogenic differentiation has several steps and they express specific gene markers sequentially. It was reported that Nucleoside diphosphate linked moiety X-type motif7 (NUDT7) is expressed in muscle. To determine NUDT7 function in myogenesis in vitro, we performed the experiments with C2C12 myoblasts. The cells were pre-cultured in the 10% FBS-growth medium for a day and were induced differentiation in 2% HS-DMEM differentiation medium for eight days. They were forced to overexpress NUDT7 in lipofection method. They were harvested and were analyzed for mRNA and protein expression. In the results, NUDT7 mRNA expression was increased during myogenic differentiation. Myf5 was increasingly expressed at the early stage (day 2 and 3) followed by Mrf4, Myogenin and Myoglobin. The expression pattern of NUDT7 is similar to that of Myogenin and Myoglobin. The NUDT7 overexpression activated endogenous NUDT7 expression and MyHC1 mRNA expression, suggesting that NUDT7 overexpression partly promoted slow myofiber formation, which may explain the mechanisms to modulate the types of myofibers.