title: Structure and function of Parkin E3 ubiquitin ligase reveals aspects of RING and HECT ligases.
abstract: Parkin is a RING-between-RING E3 ligase that functions in the covalent attachment of ubiquitin to specific substrates, and mutations in Parkin are linked to Parkinson's disease, cancer and mycobacterial infection. The RING-between-RING family of E3 ligases are suggested to function with a canonical RING domain and a catalytic cysteine residue usually restricted to HECT E3 ligases, thus termed 'RING/HECT hybrid' enzymes. Here we present the 1.58 Å structure of Parkin-R0RBR, revealing the fold architecture for the four RING domains, and several unpredicted interfaces. Examination of the Parkin active site suggests a catalytic network consisting of C431 and H433. In cells, mutation of C431 eliminates Parkin-catalysed degradation of mitochondria, and capture of an ubiquitin oxyester confirms C431 as Parkin's cellular active site. Our data confirm that Parkin is a RING/HECT hybrid, and provide the first crystal structure of an RING-between-RING E3 ligase at atomic resolution, providing insight into this disease-related protein.
authors.affiliation: Elan Pharmaceuticals, 180 Oyster Point Boulevard, South San Francisco, California 94080, USA.
authors.forename: B E
authors.initials: BE
authors.lastname: Riley
authors.forename: J C
authors.initials: JC
authors.lastname: Lougheed
authors.forename: K
authors.initials: K
authors.lastname: Callaway
authors.forename: M
authors.initials: M
authors.lastname: Velasquez
authors.forename: E
authors.initials: E
authors.lastname: Brecht
authors.forename: L
authors.initials: L
authors.lastname: Nguyen
authors.forename: T
authors.initials: T
authors.lastname: Shaler
authors.forename: D
authors.initials: D
authors.lastname: Walker
authors.forename: Y
authors.initials: Y
authors.lastname: Yang
authors.forename: K
authors.initials: K
authors.lastname: Regnstrom
authors.forename: L
authors.initials: L
authors.lastname: Diep
authors.forename: Z
authors.initials: Z
authors.lastname: Zhang
authors.forename: S
authors.initials: S
authors.lastname: Chiou
authors.forename: M
authors.initials: M
authors.lastname: Bova
authors.forename: D R
authors.initials: DR
authors.lastname: Artis
authors.forename: N
authors.initials: N
authors.lastname: Yao
authors.forename: J
authors.initials: J
authors.lastname: Baker
authors.forename: T
authors.initials: T
authors.lastname: Yednock
authors.forename: J A
authors.initials: JA
authors.lastname: Johnston
mesh_terms: D055162:Biocatalysis; D020134:Catalytic Domain; D006801:Humans; D008928:Mitochondria / Q000378:metabolism; D008958:Models, Molecular; D009154:Mutation; D010300:Parkinson Disease / Q000201:enzymology / Q000235:genetics; D010649:Phenylalanine; D017434:Protein Structure, Tertiary; D044767:Ubiquitin-Protein Ligases / Q000737:chemistry* / Q000378:metabolism*
chemical_list: D010649:Phenylalanine; D044767:Ubiquitin-Protein Ligases; C111567:parkin protein