The SCFbeta-TRCP-ubiquitin ligase complex associates specifically with phosphorylated destruction motifs in IkappaBalpha and beta-catenin and stimulates IkappaBalpha ubiquitination in vitro.

ABSTRACT: Ubiquitin-mediated proteolysis has a central role in controlling the intracellular levels of several important regulatory molecules such as cyclins, CKIs, p53, and IkappaBalpha. Many diverse proinflammatory signals lead to the specific phosphorylation and subsequent ubiquitin-mediated destruction of the NF-kappaB inhibitor protein IkappaBalpha. Substrate specificity in ubiquitination reactions is, in large part, mediated by the specific association of the E3-ubiquitin ligases with their substrates. One class of E3 ligases is defined by the recently described SCF complexes, the archetype of which was first described in budding yeast and contains Skp1, Cdc53, and the F-box protein Cdc4. These complexes recognize their substrates through modular F-box proteins in a phosphorylation-dependent m

SUBMITTER: Winston JT 

PROVIDER: S-EPMC316433 | biostudies-literature | 1999 Feb

REPOSITORIES: biostudies-literature