Cullin-4A (CUL4A)

Core part of numerous cullin-RING-based E3 ubiquitin-protein ligase complexes that mediate the ubiquitination of target proteins. As a scaffold protein can contribute to catalysis through positioning of the substrate and the ubiquitin-conjugating enzyme.

The E3 ubiquitin-protein ligase activity of the complex is determined by the neddylation of the cullin subunit and is inhibited by the institution of the deneddylated cullin subunit with TIP120A/CAND1. The functional specificity of the E3 ubiquitin-protein ligase complex depends upon the variable substrate recognition component.