Fig. 4.

Cell-specific Yes-associated protein/transcriptional coactivator with PDZ-binding motif (YAP/TAZ) activation in postischemic liver after ischemia-reperfusion (I/R). A: YAP and TAZ nuclear expression in sham liver and postischemic liver 96 h after I/R. Original magnification is ×200. PV, portal vein; CV, central vein. B: nuclear YAP and TAZ expression in hepatic stellate cells (HSCs), biliary epithelial cells, and reactive ductular cells was determined 96 h after I/R by staining of serial sections for YAP or TAZ with desmin, CK19, or CK8/18, respectively. Representative HSCs, biliary epithelial cells, and reactive ductular cells positive for YAP or TAZ are marked by arrows. Original magnification is ×400. C: concomitant activation of YAP and TAZ occurs in HSCs. Serial liver sections obtained 96 h after I/R were stained for YAP and TAZ. Representative HSCs positive for YAP and TAZ are marked by arrows. Original magnification is ×400. D: nuclear YAP and TAZ expression increases in HSCs, but not hepatocytes, after I/R. Cytoplasmic and nuclear fractions from hepatocytes and HSCs isolated 96 h after I/R were analyzed by Western blot and stained with YAP, phosphorylated YAP (Ser127), TAZ, and phosphorylated TAZ (Ser89).