Key assembly factor of SCF (SKP1-CUL1-F-box protein) E3 ubiquitin ligase complexes that promotes the exchange of the substrate-recognition F-box subunit in SCF complexes, thereby playing a key role in the cellular repertoire of SCF complexes. Acts as a F-box protein exchange factor. The exchange activity of CAND1 is coupled with cycles of neddylation conjugation: in the deneddylated state, cullin-binding CAND1 binds CUL1-RBX1, increasing dissociation of the SCF complex and promoting exchange of the F-box protein. Probably plays a similar role in other cullin-RING E3 ubiquitin ligase complexes (By similarity). May indirectly enhance transcription from various types of promoters. Interacts with TBP (PubMed:8954946). Part of a complex that contains CUL1 and RBX1. Interacts with unneddylated cullins: interacts with CUL1, CUL2, CUL3, CUL4A, CUL4B and CUL5. Does not bind neddylated CUL1. Interaction with cullins is abolished in presence of COMMD1, which antagonizes with CAND1 for interacting with cullins. Interacts with ERCC6 (By similarity). Interacts with DCUN1D1, DCUN1D2, DCUN1D3, DCUN1D4 AND DCUN1D5; these interactions are bridged by cullins and strongly inhibits the neddylation of cullins (By similarity). Predominantly cytoplasmic. Detected in heart, brain, spleen, liver, skeletal muscle, kidney and testis. Belongs to the CAND family.