Fig. 4

CRTC2 promoted EMT through CREB-Smad2/3 signaling pathway. C57BL/6 J mice were intraperitoneally injected with STZ (30 mg/Kg) or PBS (control). The STZ mice were fed with high fat diet and control mice were fed with normal diet. p-Smad3 (A) and p-CREB (ser133) (B) were detected by immunohistochemistry in the kidney of mice. C HK-2 cells were transfected with α-SMA luciferase constructs with or without control vector, as well as CRTC2 overexpression plasmid (CRTC2-Flag) or SiRNA CREB for 48 h. The cells were treated with TGF-β1 (8 ng/ml, 48 h). Luciferase activity was assayed in triplicate. **p < 0.01 compared with Control group. ^#p < 0.05 compared with TGF-β1 group, ^##p < 0.01 compared with TGF-β1 group. ^$$p < 0.01 compared with CRTC2-Flag group. D–I HK-2 cells were transfected with or without control vector, as well as CRTC2 overexpression plasmid (CRTC2-Flag) or SiRNA CREB for 48 h. And cells were treated with TGF-β1 (8 ng/ml, 48 h). Protein expression were detected by Western blot (D). Gene expression was analyzed by real-time PCR (E–I). All experiments was assayed in triplicate (E–I), *p < 0.05,**p < 0.01 compared with control group. ^#p < 0.05, ^##p < 0.01 compared with TGF-β1 group. ^$$p < 0.01 compared with CRTC2 overexpression plasmid group