The heterotrimeric linear ubiquitin chain assembly complex (LUBAC; composed of HOIP that harbours the essential enzymatic activity, and HOIL-1 and SHARPIN that promote complex assembly and stability) coordinates NF-κB activation via linear ubiquitylation of RIPK1 and NEMO within complex I. As briefly touched on above, HOIL-1- and HOIP-deficient patients survive but present with immunodeficiency and multi-organ autoinflammation, including dermatitis [106,142,143]. Here, RNF31 is linked to Immunodeficiency.