Fig. 6.

Co-knockdown of HuR and AUF1 abolishes the pH-responsive increases in PEPCK mRNA and protein. LLC-PK₁-F⁺-9C cells were transfected with 50 nM control siRNA or 100 nM AUF1 siRNAs in the absence or presence of 30 nM HuR siRNA. After 2 days, the cells were maintained in either normal (pH 7.4) or acidic medium (pH 6.9) for 24 h and then harvested with lysis buffer or TRIzol. A: Western blot analysis was performed to monitor the expression of PEPCK, HuR, AUF1, and βT proteins. B: levels of PEPCK and GAPDH mRNAs were determined by RT-qPCR. C: levels of PEPCK and βT proteins were quantified from the Western blots. The relative levels of PEPCK mRNA (B) and protein (C) in the normal (hatched bars) and acidic samples (filled bars) are means ± SE of triplicate samples.