Chrebp O-glycosylation, protein stability, and recruitment to the L-PK promoter are increased in FoxO1 knockout liver.

<p>(A and B) The liver samples isolated from L-FoxO1-KO and the control mice at the points of 24 hr fasted or 3 hr refed after 24 hr starvation were subjected to immunoprecipitation with anti-Chrebp antibody followed by blotting with anti-O-GlcNAc, anti-OGT (A) or anti-ubiquitin antibody (B). Input indicates the expression levels of Chrebp, FoxO1 or tubulin. Quantitative analyses were performed by assessment of O-glycosylation (A) or ubiquitination (B) levels compared with the protein level of Chrebp using densitometry, showing as a bar graph below the results of blotting. (C) The liver extracts were also subjected to chromatin immunoprecipitation assay using anti-Chrebp antibody and primers for the L-PK promoter. Quantitative analyses were performed using densitometry. Input indicates extracted DNA prior to immunoprecipitation. Experiments were repeated at least three times. Data represent mean ± SEM. *P<0.05. (D) Hematoxylin-and-eosin (H-E) staining of the liver sections from 24 hr fasted L-FoxO1-KO and the control mice. Magnification, x100. (E) Hepatic triglyceride (TG) contents in 24 hr fasted or 3 hr refed (after 24 hr starvation) L-FoxO1-KO and the control mice (n = 6 for each group). Data represent mean ± SEM.