Fig. 6

PERK regulates p38δ MAPK expression in HSCs. RNA-sequencing analysis is performed using the RNAs collected from PA-treated LX-2 cells and PERK siRNA-transfected PA-treated LX-2 cells. DEGs between PA (n = 3) and PERK siRNA + PA (n = 3) are determined using CLC Genomics Workbench v24. The mRNAs with a fold change > 2 and FDR p-value < 0.05 between the two groups are selected as DEGs. (a) DEGs are visualized using the heatmap. (b) Volcano plots show that EIF2AK3 (PERK), IL1B (IL-1β), and MAPK13 (p38δ MAPK) are markedly downregulated in PERK siRNA + PA compared to PA. Furthermore, p38δ MAPK expression is examined in PERK-knockdown and PERK-overexpression LX-2 cells. (c) p38δ MAPK mRNA (c) and protein (d) expression are evaluated using RT-PCR (n = 4) and WB, respectively. Supplementary Fig. S8 presents the original membranes of WB. p38δ MAPK mRNA (e) and protein (f) expression are evaluated using RT-PCR (n = 4) and WB, respectively. Supplementary Fig. S9 shows the original membranes of WB. Data are presented as the mean ± SE. Statistical analysis is performed using Student’s t-test. **p < 0.01. Abbreviations: PERK, protein kinase R-like endoplasmic reticulum kinase; IL-1β, interleukin-1 beta; MAPK, mitogen-activated protein kinase; GAPDH, glyceraldehyde 3-phosphate dehydrogenase; WB, western blotting; RT, reverse transcription; siRNA, small interfering RNA; HSCs, hepatic stellate cells; SE, standard error; PA, palmitic acid; DEGs, differentially expressed genes; FDR, false discovery rate.