Fig. 6.

HRD1 promotes eIF2α ubiquitylation and degradation. a The endogenous eIF2α and CHOP expression was significantly decreased by HRD1 overexpression in HKC-8 cells. b The mRNA level of eIF2α showed no significant differences in the presence or absence of HRD1 overexpression. c More ubiquitin conjugated to eIF2α was detected in the cells overexpressing HRD1 compared with no HRD1 transfection. d Quantification of ubiquitin conjugated to eIF2α as in (c), normalized to actin expression. e Palmitic acid (PA) treatment of HKC-8 cells significantly increased the expressions of p-eIF2α and eIF2α, but their expressions were dose-dependently decreased with Ad-HRD1 infection. Quantification of p-eIF2α (f) and eIF2α (g) expression as in (d), normalized to actin expression. Bars are means ± S.E. from three independent experiments. n.s. means no significance, *P < 0.05, **P<0.01