FIG. 7.

TRAF2 directly promotes glucose counterregulation in hepatocytes. A: Primary hepatocyte cultures were isolated from C57BL/6 wild-type mice (10–11 weeks) and infected with GFP or TRAF2 adenoviruses. Cell extracts were prepared 16 h after infection and immunoblotted with antibodies against TRAF2 or tubulin. B: Primary hepatocytes were infected with GFP or TRAF2 adenoviruses and treated with glucagon 16 h after infection. HGP was measured 4 h after glucagon stimulation and normalized to total protein levels. n = 4. C: Primary hepatocytes were infected with GFP or TRAF2 adenoviruses and treated with or without glucagon 16 h after infection. Total RNAs were extracted 2 h after glucagon stimulation and used to measure the mRNA abundance of PEPCK and G6Pase by qPCR. The expression of PEPCK and G6Pase was normalized to 36B4 expression. D: Primary hepatocytes were infected with GFP or TRAF2 adenoviruses and treated with DB-cAMP (100 μmol/L for 2 h) 16 h after infection. Total RNAs were extracted and used to measure the mRNA abundance of PEPCK and G6Pase by qPCR. E: Primary hepatocytes were coinfected with CREB and GFP or TRAF2 adenoviruses. Sixteen hours after infection, the cells were treated with glucagon or DB-cAMP for 30 min. Cell extracts were immunoblotted with anti–phospho-CREB (pSer133) or anti-CREB antibodies. Data are mean ± SEM. *P < 0.05. AU, arbitrary unit.