ASK1 and its structure. Schematic representation of the domain structure of ASK1 with the structural models of individual domains. TBD, thioredoxin-binding domain; TPR, tetratricopeptide repeat domain; PH, pleckstrin homology domain; CRR, central regulatory region; KD, kinase domain; SAM, sterile-alpha motif, the 14-3-3 site is shown in red. The structures of individual ASK1 domains: ASK1-TBD, the NMR-based structural model of thioredoxin-binding domain shown in yellow [29]; ASK1-CRR, the crystal structure of central regulatory region shown in teal and green (PDB ID: 5ULM [41]); ASK1-KD, the crystal structure of a dimer of kinase domain shown in orange and brown, and three autophosphorylation sites Thr813, Thr838 and Thr842 are shown as spheres (PDB ID: 2CLQ [42]); SAM, the crystal structure of SAM domain from ASK3 shown in grey (PDB ID: 6V0M [43]).