Recruitment of a ROC1-CUL1 ubiquitin ligase by Skp1 and HOS to catalyze the ubiquitination of I kappa B alpha.
Activation of the transcription factor NF-kappa B in response to proinflammatory stimuli requires the phosphorylation-triggered and ubiquitin-dependent degradation of the NF-kappa B inhibitor, I kappa B alpha. Here, we show the in vitro reconstitution of the phosphorylation-dependent ubiquitination of I kappa B alpha with purified components. ROC1, a novel SCF-associated ... protein, is recruited by cullin 1 to form a quatemary SCFHOS-ROC1 holenzyme (with Skp1 and the beta-TRCP homolog HOS). SCFHOS-ROC1 binds IKK beta-phosphorylated I kappa B alpha and catalyzes its ubiquitination in the presence of ubiquitin, E1, and Cdc34. ROC1 plays a unique role in the ubiquitination reaction by heterodimerizing with cullin 1 to catalyze ubiquitin polymerization.
Mesh Terms:
Amino Acid Sequence, Cell Cycle Proteins, Cullin Proteins, DNA-Binding Proteins, Hela Cells, Humans, I-kappa B Kinase, I-kappa B Proteins, Molecular Sequence Data, Peptide Synthases, Phosphorylation, Protein-Serine-Threonine Kinases, S-Phase Kinase-Associated Proteins, SKP Cullin F-Box Protein Ligases, Ubiquitins
Amino Acid Sequence, Cell Cycle Proteins, Cullin Proteins, DNA-Binding Proteins, Hela Cells, Humans, I-kappa B Kinase, I-kappa B Proteins, Molecular Sequence Data, Peptide Synthases, Phosphorylation, Protein-Serine-Threonine Kinases, S-Phase Kinase-Associated Proteins, SKP Cullin F-Box Protein Ligases, Ubiquitins
Mol. Cell
Date: Apr. 01, 1999
PubMed ID: 10230406
View in: Pubmed Google Scholar
Download Curated Data For This Publication
118503
Switch View:
- Interactions 8