Trip12 controls Sox6 protein level in C2C12 cells. (A) siRNA-mediated knockdown of Trip12 resulted in an increase of Sox6 protein levels in C2C12 cells. C2C12 cells were transfected with siRNA for either EGFP (negative control) or Trip12 in triplicate, and lysates were analyzed by Western blotting using a 7.5% gel. (B) Densitometric analysis of the Western blot in (A) shows approximately 3-fold increase in the Sox6 protein level in Trip12 siRNA-treated cells, while the Tbp protein level was not affected. Data are normalized for those from EGFP siRNA-transfected cells and represented as mean ± SD (n = 3). (C) Trip12 knockdown lowered mRNA level of Myh7, a known Sox6 target. Total RNA was extracted from mock- or siRNA-transfected C2C12 cells, and mRNA levels of Trip12 and Myh7 were quantified by reverse transcription-quantitative PCR (RT-qPCR). Data are normalized for those from EGFP siRNA-transfected cells and represented as mean ± SD (n = 3). **p < 0.005.