Figure 5.

HOIP restrains formation of the cell death–inducing FADD–RIPK1–caspase‐8–c‐FLIP_L–containing complex in hepatocytes, independently of its gene‐activating function. (A) Cell viability assay of primary hepatocytes isolated from Hoip^flox and Hoip^Δhep mice, treated with 1 μg/mL TNF for 24 hours in the presence or absence of 1 μg/mL CHX. Unpaired two‐tailed t test was employed for statistical analysis. (B) Immunoprecipitation of the FADD‐associated complex in z‐VAD‐fmk(zVAD)–treated (24 hours) primary hepatocytes from Hoip^flox (F) and Hoip^Δhep (Δ) mice in the absence or presence of 1 μg/mL CHX. Asterisks indicate unspecific bands. (C) Schematic representation of the role of LUBAC in HOIP‐proficient and HOIP‐deficient hepatocytes. Abbreviations: GAPDH, glyceraldehyde 3‐phosphate dehydrogenase; IP, immunoprecipitation.