Jci_page_head_homepage_01 Jci_page_head_homepage_02
Renaud Dentin, Fadila Benhamed, Jean-Paul Pégorier, Fabienne Foufelle, Benoit Viollet, Sophie Vaulont, Jean Girard, Catherine Postic
Published in Volume 115, Issue 10
J Clin Invest. 2005; 115(10):2843–2854 doi:10.1172/JCI25256
Abstract | Full text | PDF | Supplemental material
Options: View larger image (or click on image)
Medium
Figure 9

Inhibitory effect of PUFAs on ChREBP activation and translocation. Under basal conditions of low glucose and insulin concentrations, ChREBP is phosphorylated and localized in the cytosol of hepatocytes. Its nuclear translocation is rapidly induced under high glucose and insulin concentrations. The nuclear translocation of ChREBP is controlled by a mechanism of dephosphorylation and phosphorylation. While the dephosphorylation of serine residue 196 (Ser196) allows ChREBP translocation into the nucleus, the dephosphorylation of threonine residue 666 (Thr666) alleviates DNA-binding inhibition. Protein phosphatase 2A (PP2A), selectively activated by X5P, is believed to be responsible for both cytosolic and nuclear dephosphorylation of ChREBP. Then ChREBP binds its response element (ChoRE) to activate glycolytic and lipogenic gene expression. In the presence of PUFAs, ChREBP is retained in the cytosol through the specific inhibition of GK and G6PDH activities, key enzymes of glycolysis and of the pentose phosphate pathway, respectively.