title: The human Dcn1-like protein DCNL3 promotes Cul3 neddylation at membranes.
abstract: Cullin (Cul)-based E3 ubiquitin ligases are activated through the attachment of Nedd8 to the Cul protein. In yeast, Dcn1 (defective in Cul neddylation 1 protein) functions as a scaffold-like Nedd8 E3-ligase by interacting with its Cul substrates and the Nedd8 E2 Ubc12. Human cells express 5 Dcn1-like (DCNL) proteins each containing a C-terminal potentiating neddylation domain but distinct amino-terminal extensions. Although the UBA-containing DCNL1 and DCNL2 are likely functional homologues of yeast Dcn1, DCNL3 also interacts with human Culs and is able to complement the neddylation defect of yeast dcn1Delta cells. DCNL3 down-regulation by RNAi decreases Cul neddylation, and overexpression of a Cul3 mutant deficient in DCNL3 binding interferes with Cul3 function in vivo. Interestingly, DCNL3 accumulates at the plasma membrane through a conserved, lipid-modified motif at the N terminus. Membrane-bound DCNL3 is able to recruit Cul3 to membranes and is functionally important for Cul3 neddylation in vivo. We conclude that DCNL proteins function as nonredundant Cul Nedd8-E3 ligases. Moreover, the diversification of the N termini in mammalian Dcn1 homologues may contribute to substrate specificity by regulating their subcellular localization.
authors.affiliation: Institute of Biochemistry, Eidgenössiche Technische Hochschule, 8093 Zurich, Switzerland.
authors.forename: Nathalie
authors.initials: N
authors.lastname: Meyer-Schaller
authors.forename: Yang-Chieh
authors.initials: YC
authors.lastname: Chou
authors.forename: Izabela
authors.initials: I
authors.lastname: Sumara
authors.forename: Dale D O
authors.initials: DD
authors.lastname: Martin
authors.forename: Thimo
authors.initials: T
authors.lastname: Kurz
authors.forename: Nadja
authors.initials: N
authors.lastname: Katheder
authors.forename: Kay
authors.initials: K
authors.lastname: Hofmann
authors.forename: Luc G
authors.initials: LG
authors.lastname: Berthiaume
authors.forename: Frank
authors.initials: F
authors.lastname: Sicheri
authors.forename: Matthias
authors.initials: M
authors.lastname: Peter
mesh_terms: D000818:Animals; D001665:Binding Sites; D019556:COS Cells; D002460:Cell Line; D002462:Cell Membrane / Q000378:metabolism*; D002522:Chlorocebus aethiops; D044842:Cullin Proteins / Q000235:genetics / Q000378:metabolism*; D005455:Fluorescent Antibody Technique; D005816:Genetic Complementation Test; D006367:HeLa Cells; D006801:Humans; D015151:Immunoblotting; D047468:Immunoprecipitation; D009154:Mutation; D000075687:NEDD8 Protein; D011485:Protein Binding; D034741:RNA, Small Interfering / Q000235:genetics; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics; D014162:Transfection; D044767:Ubiquitin-Protein Ligases / Q000235:genetics / Q000378:metabolism*; D054875:Ubiquitination; D014452:Ubiquitins / Q000235:genetics / Q000378:metabolism
chemical_list: C503645:CUL3 protein, human; D044842:Cullin Proteins; C502135:Dcn1 protein, S cerevisiae; D000075687:NEDD8 Protein; C082860:NEDD8 protein, human; D034741:RNA, Small Interfering; D029701:Saccharomyces cerevisiae Proteins; D014452:Ubiquitins; D044767:Ubiquitin-Protein Ligases