Figure 5.

SGK3 overexpression accelerated cell cycle progression and promoted C2C12 cell proliferation; SGK3 inhibition impeded cell cycle progression and inhibited C2C12 cell proliferation. (a) The protein level of SGK3 24 hours after C2C12 cells were transfected with pcDNA3.1-SGK3. pcDNA3.1-SGK3 increased the protein level of SGK3. (b) The protein level of SGK3 24 hours after C2C12 cells transfected with Si-SGK3-3. Si-SGK3-3 decreased the protein level of SGK3. (c) Flow cytometry analysis after C2C12 cells were transfected with pcDNA3.1-SGK3 or Si-SGK3-3. pcDNA3.1-SGK3 lowered the percentage of G1 phase cells, increased the percentage of S phase cells. Si-SGK3-3 increased the percentage of G1 phase cells and decreased the percentage of S phase cells. (d) mRNA level of cell cycle genes measured by qPCR. pcDNA3.1-SGK3 increased the mRNA level of CCNB. Si-SGK3-3 decreased the mRNA level of CCNA and CCND. (e) Western blot results after C2C12 cells were transfected with pcDNA3.1-SGK3. pcDNA3.1-SGK3 increased the protein level of CCNB, decreased the protein level of P21. (f) Western blot results after C2C12 cells were transfected with Si-SGK3-3. Si-SGK3-3 decreased the protein level of CCNB and CCND, increased the protein level of P21. * p < 0.05, ** p < 0.01, *** p < 0.001. All experiments were repeated three times, and results are presented as mean ± S.E.M