This entry represents the Ariadne domain found in the Ariadne subfamily E3 ubiquitin ligase proteins [4]. The C-terminal Ariadne domain adopts an elongated four-helix bundle consisting of an antiparallel arrangement of seven-to-ten-turn long helices. The Ariadne domain is straddled on one side by the IBR domain, and on the other by the RING2 domain. Notably, the Ariadne domain embraces the surface of RING2 containing the catalytic Cys357 [1]. The ariadne Domain Masks the HHARI Catalytic Cys357 and Inhibits Intrinsic E3 Activity [1].

1: Structure of HHARI, a RING-IBR-RING ubiquitin ligase: autoinhibition of an Ariadne-family E3 and insights into ligation mechanism. Duda DM, Olszewski JL, Schuermann JP, Kurinov I, Miller DJ, Nourse A, Alpi AF, Schulman BA; Structure. 2013;21:1030-1041. PMID:23707686

2: Structural insights into the mechanism and E2 specificity of the RBR E3 ubiquitin ligase HHARI. Yuan L, Lv Z, Atkison JH, Olsen SK; Nat Commun. 2017;8:211. PMID:28790309

3: Structural Studies of HHARI/UbcH7 approximately Ub Reveal Unique E2 approximately Ub Conformational Restriction by RBR RING1. Dove KK, Olszewski JL, Martino L, Duda DM, Wu XS, Miller DJ, Reiter KH, Rittinger K, Schulman BA, Klevit RE; Structure. 2017;25:890-900. PMID:28552575

4: Comparative genomics of the RBR family, including the Parkinson's disease-related gene parkin and the genes of the ariadne subfamily. Marin I, Ferrus A; Mol Biol Evol 2002;19:2039-2050. PMID:12446796