Cullin Associated And Neddylation Dissociated Protein 1 (CAND1)

The rat Tip120 protein contains 1,230 amino acids and has a calculated molecular mass of 135 kD. CAND1 prevented binding of SKP1 and SKP2 to CUL1, while dissociation of CAND1 from CUL1 promoted the reverse reaction. Neddylation of CUL1 or the presence of SKP1 and ATP caused CAND1 dissociation. These data suggested that CAND1 regulates the formation of the SCF (SKP1, CUL1/Cdc53, F box protein) complex and that its dissociation from CUL1 is coupled with the incorporation of F box proteins into the SCF complex, causing their destabilization.CAND1 formed a ternary complex with CUL1 and ROC1. It dissociated SKP1 from CUL1 and inhibited SCF ligase activity in vitro. Suppression of CAND1 in vivo increased the level of the CUL1-SKP1 complex.