Figure 7.

DUSP3 is involved in IR phosphorylation and signaling and its expression is reduced under HFD. (a–d) DUSP3 expression is reduced in mice liver under HFD. (a–b) DUSP3 protein expression. mRNA levels using qRT-PCR (c) and RNAseq (d) in liver extracts from 18-month-old WT mice under chow diet (CD) and high fat diet (HFD). (a) representative Western blot in liver samples of WT mice under CD and HFD. (b) Quantification of protein expression was normalized on beta-actin while (c) quantification of transcripts was normalized on HPRT housekeeping gene. Data are presented as mean ± SD. N = 3 mice in each group. (e–f) Protein level and phosphorylation of IR, AKT, ERK, GSK3 and p38 in the mouse liver tissue from DUSP3-KO and WT mice under CD and HFD. Liver homogenates protein extract were subjected to Western blot using anti-phospho IR, anti-phospho AKT, anti-phospho-ERK, anti-phospho GSK3 and anti-phospho p38. Anti-IR, AKT, ERK, GSK3 and p38 were used for normalization of each phosphorylation level. Global normalization was achieved using anti-b-actin antibody. (e) Representative blots are shown. (f) The average relative grayscale values normalized with the control protein were obtained from 4 to 6 mice per group and results are expressed as mean ± SD. *P < 0.05; **P < 0.01. Non-cropped original blots for each shown phospho-protein and protein are in the extended Supplementary Fig. 7 in the Supplementary Information.