Fig. 7: TAZ positively regulated USP14 expression at the transcriptional level.

A, B SW1990 cells were transfected with the TAZ-Flag (2.0 μg plasmid according to per well of 6-well plate) and TAZ-S89A plasmids (1.0 μg plasmid according to per well of 6-well plate), immunoblotting and RT-qPCR were used to measure the protein and mRNA expression levels of USP14 and TAZ target genes. C, D SW-1990 cells were transfected with the shLATS1/2 (LATS1 and LATS2 double knockdown) or shSTK3/4 (STK3 and STK4 double knockdown) plasmids, and immunoblotting and RT-qPCR were used to measure the protein and mRNA expression levels of USP14 and TAZ target genes. E A schematic diagram of the USP14 promoter region with potential TEAD1/4 binding sites (TBSs) was shown. The wild-type and TBS mutant sequences were indicated. R1, R2, and R3 indicate three sites (Region 1, Region 2, and Region 3) in the USP14 promoter containing the potential TBSs. F The luciferase reporter assay showed that TAZ promoted the expression of USP14 by affecting the USP14 promoter region (R1). Renilla luciferase activity was used as the internal reference. Data were representative of three independent experiments with similar results, and each experiment consisted of three repeated biological samples. G A ChIP-qPCR assay was used to examine the binding of TAZ and the USP14 promoter in TAZ^S89A-Flag overexpressing PANC-1 cells. CTGF was used as a positive control. Data were representative of three independent experiments with similar results.