Silencing of Myh3 Gene by siRNA Inhibits Glycolysis in C2C12 Cells / 中国生物化学与分子生物学报

ABSTRACT

The Myh3 (myosin heavy chain 3) gene is a marker gene of muscle cell differentiation and regulates the utilization of energy in muscle cells, but whether it affects the glycolysis process of muscle cells in different states is rarely reported. In this paper, the expression patterns of Myh3 and glycolysis-related genes Pkm (M-type pyruvate kinse), Prkag3 (protein kinase adenosine monophosphate-activated γ3-subunit), and Gsk3β (glycogen synthase kinase-3β) were studied by the qRT-PCR (quantitative-Real-Time-PCR) method using C2C12 cells at different stages of myoblast and adipogenic differentiation as models. It was found that in the process of myoblast differentiation of C2C12 cells, the relative expression trends of Myh3 and glycolysis genes Prkag3 and Pkm were basically the same, and the relative expression levels first increased, reached the peak on the second day of differentiation, and then decreased; glycogen synthase the expression trend of the inhibitory gene Gsk3β was relatively stable. In the process of adipogenic differentiation of C2C12 cells, the relative expression trend of Myh3 and glycolysis genes Prkag3 and Pkm remained basically the same, and the relative expression gradually increased, reaching the highest value on the 8th day of differentiation; glycogen synthase inhibitory gene Gsk3β expression remained stable. In the myogenic differentiation state of C2C12 cells, qRT-PCR and Western blotting were used to detect the effects of interfering Myh3 on the mRNA and protein expressions of glycolysis-related genes Pkm, Prkag3, and Gsk3β. The results showed that after interfering with Myh3, the mRNA expressions of glycolysis genes Pkm and Prkag3 were significantly decreased (P 0.05). The protein levels of Myh3 and Pkm were significantly lower than those in the blank group and NC group. Under the adipogenic differentiation state of C2C12 cells, after interfering with Myh3, the mRNA levels of glycogen synthase inhibitor Gsk3β and glycolysis gene Prkag3 were significantly increased (P<0.01), and the mRNA level of glycolysis gene Pkm was decreased; the protein levels of Myh3 and Pkm in the Myh3 interference group were also lower than those in the blank group and NC group. Based on the above studies, there are significant differences in the levels of glycolysis in C2C12 cells in the myogenic and adipogenic states, and the expression patterns of Myh3 and glycolysis genes are similar. Further results showed that Myh3 suppression could inhibit the glycolysis of C2C12 cells in the myogenic state without affecting the glycogen synthesis. Unlike in the myogenic state, interfering expression of Myh3 in the adipogenic state of C2C12 cells inhibited both glycogen synthesis and glycolysis.