Upon cellular activation , I kappa B alpha is phosphorylated , polyubiquitinated , and degraded in the proteasome .
upon cellular activation , i kappa b alpha is phosphorylated , polyubiquitinated , and degraded in the proteasome .
O O O O B-protein_molecule I-protein_molecule I-protein_molecule I-protein_molecule O O O O O O O O O B-protein_complex O