RIPK1 and psoriasis: In psoriasis, TNF-α primarily engages TNFRI, forming homotrimers that induce intracellular signaling through complex I. This complex involves TNFR1-associated death domain protein (TRADD), TRAF2, receptor-interacting serine/threonine-protein kinase 1 (RIPK1), a cellular inhibitor of apoptosis protein 1 (cIAP1) or cIAP2, and the linear ubiquitin chain assembly complex.