Fig 2: eIF2A affects the expression levels of autophagic receptor, p62, in primary adipocytes upon differentiation. (A) Western blot of key adipogenic and autophagic markers: PPARγ, LC3B (represented by LC3‐I (upper band) and LC3‐II (lower band) isoforms) and p62 in wild‐type and eIF2A‐KO adipocytes isolated from WAT and BAT tissues before and after differentiation. (B) Real‐time PCR. Relative C t values are shown; C t values were normalized to the actin signal and plotted relative to undifferentiated p62 mRNA levels. All data presented as means ± SEM, N = 5 independent points per each RT‐PCR

Fig 3: Plasma glucose concentrations during the intraperitoneal glucose tolerance (1 g/kg body weight) and insulin tolerance (0.35 µg/g body weight) tests in WT (C57BL/6J) and eIF2A‐KO (16–18 weeks old) mice fed on normal and high‐fat (HF) diets. (A) Intraperitoneal glucose tolerance test (GTT) in male mice following fasting for 5 h (left panels) and 16 h (right panels). (B) Intraperitoneal GTT in female mice following fasting for 5 h (left panels) and 16 h (right panels). (C) Insulin sensitivity. Male (left panel) and female (right panel) mice fed on normal and HF diets were fasted for 5 h and intraperitoneally injected with insulin. All data presented as means ± SEM, N = 5–8 animals/group

Fig 4: Survival of mice of the indicated genotypes and genders and assessment of behavior and locomotor activity. (A) Comparison of longevity group survival between WT (C57BL/6J) mice and eIF2A‐KO mice (males and females monitored over 1 year) (Number of animals used for the analysis: WT Males = 83, eIF2A‐KO Males = 65, WT Females = 85, eIF2A‐KO Females = 84). (B) WT and eIF2A‐KO female mice were placed in individual home cages, and their locomotion was assessed every hour for 72 h (with 12‐h light and 12‐h night [shaded grey] periods) (n = 3 for each group). (C) WT and eIF2A‐KO female mice locomotion was assessed under constant darkness every hour for 72 h (n = 3 for each group)

Fig 5: 125I induces upregulation of PERK-eIF2a-ATF4-CHOP pathway to promote apoptosis.a To explore the possible apoptosis-related pathways induced by 125I, iTRAQ was performed in HepG2 cells. The results of the signal pathway enrichment analysis of differentially expressed proteins reveals that the eIF2 signaling pathway is significantly different between the control HepG2 cells and 125I-treated HepG2 cells. b, c After HepG2 cells were treated with different doses of 125I, the proteins and mRNA levels of the PERK-eIF2-ATF4-CHOP pathway were upregulated in a dose-dependent manner, as detected by WB (b) and qPCR (c). d The mRNA levels consistently increased in animal models in a dose-dependent manner, after 125I irradiation. Total RNA was isolated from mouse tumors and the pathway-related genes were seen to be upregulated at the mRNA level, as detected by qPCR. e, f The 125I-induced apoptosis and anti-proliferation effect were compromised by PERK-RNAi. After HepG2 cells transfected with Control-RNAi or PERK-RNAi were treated by 125I, the apoptosis and anti-proliferation effect were detected by cell proliferation assay and Annexin V–FITC/PI assay. The PERK-RNAi abrogated 125I-induced apoptosis and anti-proliferation effect. All the experiments were performed in triplicate and the data are presented as the mean ± SD. The t-test was used for data analysis. *P < 0.05, **P < 0.01