title: The Cullin-RING E3 ubiquitin ligase CRL4-DCAF1 complex dimerizes via a short helical region in DCAF1.
abstract: The cullin4A-RING E3 ubiquitin ligase (CRL4) is a multisubunit protein complex, comprising cullin4A (CUL4), RING H2 finger protein (RBX1), and DNA damage-binding protein 1 (DDB1). Proteins that recruit specific targets to CRL4 for ubiquitination (ubiquitylation) bind the DDB1 adaptor protein via WD40 domains. Such CRL4 substrate recognition modules are DDB1- and CUL4-associated factors (DCAFs). Here we show that, for DCAF1, oligomerization of the protein and the CRL4 complex occurs via a short helical region (residues 845-873) N-terminal to DACF1's own WD40 domain. This sequence was previously designated as a LIS1 homology (LisH) motif. The oligomerization helix contains a stretch of four Leu residues, which appear to be essential for α-helical structure and oligomerization. In vitro reconstituted CRL4-DCAF1 complexes (CRL4(DCAF1)) form symmetric dimers as visualized by electron microscopy (EM), and dimeric CRL4(DCAF1) is a better E3 ligase for in vitro ubiquitination of the UNG2 substrate compared to a monomeric complex.
authors.affiliation: University of Pittsburgh Center for HIV Protein Interactions, University of Pittsburgh School of Medicine, Pittsburgh, PA 15260, USA.
authors.forename: Jinwoo
authors.initials: J
authors.lastname: Ahn
authors.forename: Zach
authors.initials: Z
authors.lastname: Novince
authors.forename: Jason
authors.initials: J
authors.lastname: Concel
authors.forename: Chang-Hyeock
authors.initials: CH
authors.lastname: Byeon
authors.forename: Alexander M
authors.initials: AM
authors.lastname: Makhov
authors.forename: In-Ja L
authors.initials: IJ
authors.lastname: Byeon
authors.forename: Peijun
authors.initials: P
authors.lastname: Zhang
authors.forename: Angela M
authors.initials: AM
authors.lastname: Gronenborn
mesh_terms: D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D000818:Animals; D002352:Carrier Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D002460:Cell Line; D006801:Humans; D007313:Insecta / Q000166:cytology; D051379:Mice; D008969:Molecular Sequence Data; D010455:Peptides / Q000378:metabolism; D055503:Protein Multimerization; D020836:Protein Structure, Quaternary; D017434:Protein Structure, Tertiary; D051381:Rats; D020449:Repetitive Sequences, Amino Acid; D012996:Solutions; D044767:Ubiquitin-Protein Ligases / Q000737:chemistry* / Q000378:metabolism*
chemical_list: D002352:Carrier Proteins; D010455:Peptides; D012996:Solutions; D044767:Ubiquitin-Protein Ligases