title: Reconstitution of G1 cyclin ubiquitination with complexes containing SCFGrr1 and Rbx1.
abstract: Control of cyclin levels is critical for proper cell cycle regulation. In yeast, the stability of the G1 cyclin Cln1 is controlled by phosphorylation-dependent ubiquitination. Here it is shown that this reaction can be reconstituted in vitro with an SCF E3 ubiquitin ligase complex. Phosphorylated Cln1 was ubiquitinated by SCF (Skp1-Cdc53-F-box protein) complexes containing the F-box protein Grr1, Rbx1, and the E2 Cdc34. Rbx1 promotes association of Cdc34 with Cdc53 and stimulates Cdc34 auto-ubiquitination in the context of Cdc53 or SCF complexes. Rbx1, which is also a component of the von Hippel-Lindau tumor suppressor complex, may define a previously unrecognized class of E3-associated proteins.
authors.affiliation: Verna and Marrs McLean Department of Biochemistry, Howard Hughes Medical Institute, Baylor College of Medicine, Houston, TX 77030, USA.
authors.forename: D
authors.initials: D
authors.lastname: Skowyra
authors.forename: D M
authors.initials: DM
authors.lastname: Koepp
authors.forename: T
authors.initials: T
authors.lastname: Kamura
authors.forename: M N
authors.initials: MN
authors.lastname: Conrad
authors.forename: R C
authors.initials: RC
authors.lastname: Conaway
authors.forename: J W
authors.initials: JW
authors.lastname: Conaway
authors.forename: S J
authors.initials: SJ
authors.lastname: Elledge
authors.forename: J W
authors.initials: JW
authors.lastname: Harper
mesh_terms: D000595:Amino Acid Sequence; D064173:Anaphase-Promoting Complex-Cyclosome; D000818:Animals; D002352:Carrier Proteins / Q000737:chemistry / Q000378:metabolism*; D018797:Cell Cycle Proteins / Q000378:metabolism; D002460:Cell Line; D044842:Cullin Proteins; D016213:Cyclins / Q000378:metabolism*; D044783:F-Box Proteins; D005656:Fungal Proteins / Q000378:metabolism*; D008025:Ligases / Q000378:metabolism; D008969:Molecular Sequence Data; D010453:Peptide Synthases / Q000378:metabolism*; D010766:Phosphorylation; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D044786:S-Phase Kinase-Associated Proteins; D044843:SKP Cullin F-Box Protein Ligases; D012441:Saccharomyces cerevisiae / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins; D016415:Sequence Alignment; D044763:Ubiquitin-Conjugating Enzymes; D043743:Ubiquitin-Protein Ligase Complexes; D044767:Ubiquitin-Protein Ligases; D014452:Ubiquitins / Q000378:metabolism*
chemical_list: C082719:CLN1 protein, S cerevisiae; D002352:Carrier Proteins; C100988:Cdc53 protein, S cerevisiae; D018797:Cell Cycle Proteins; D044842:Cullin Proteins; D016213:Cyclins; D044783:F-Box Proteins; D005656:Fungal Proteins; D011993:Recombinant Fusion Proteins; D044786:S-Phase Kinase-Associated Proteins; D029701:Saccharomyces cerevisiae Proteins; D014452:Ubiquitins; C071032:GRR1 protein, S cerevisiae; C577449:CDC34 protein, S cerevisiae; D044763:Ubiquitin-Conjugating Enzymes; D043743:Ubiquitin-Protein Ligase Complexes; D064173:Anaphase-Promoting Complex-Cyclosome; D044843:SKP Cullin F-Box Protein Ligases; D044767:Ubiquitin-Protein Ligases; D008025:Ligases; D010453:Peptide Synthases