Fig. 4.

Phospho-eif2α-ATF4-pathway-mediated FGF21 induction is enhanced in Pgam5 KO-mice-derived brown adipose tissue under fasting and cold stress. (a and b) Fgf21 gene expression in the indicated tissues from WT and Pgam5 KO mice under basal conditions or at 6 h of cold exposure after 12 h of fasting according to quantitative RT-PCR (n = 4). (c) Fgf21 gene expression in BAT derived from WT and Pgam5 KO mice under basal conditions, 18 h after fasting only (fast), 6 h after cold stress only (cold), and 6 h of cold exposure after 12 h of fasting (fast + cold) was determined using quantitative RT-PCR (n = 4). (d) Representative immunoblots for the indicated proteins derived from WT and Pgam5 KO mice under basal conditions or at 3 h of cold exposure after 12 h of fasting. (e) After fasting for 12 h, WT and Pgam5 KO mice were treated with 2.5 mg/kg body weight ISRIB or mock i.p. and subsequently exposed to cold stress. After 5 h, Fgf21 gene expression in BAT was determined using quantitative RT-PCR (WT; n = 4 for each, Pgam5 KO; mock n = 3, ISRIB n = 4). Data are expressed as the mean ± SEM, *p < 0.05, **p < 0.01, ***p < 0.001; two-way ANOVA/Bonferroni post-test (a, b, c, and e). BAT, brown adipose tissue; iWAT, inguinal white adipose tissue; CNS, central nervous systems.