Component of the CUL4-RBX1-CDD (COP10-DDB1a-DET1) E3 ubiquitin-protein ligase complex which mediates the ubiquitination and subsequent proteasomal degradation of target proteins. Participates in the CDD complex to light-mediated control of development. May repress photomorphogenesis through enhancing COP1 E3 ubiquitin-protein ligase activity. Acts together with the CUL4-DDB1-COP1-SPA E3 ubiquitin-protein ligase complexes in the repression of photomorphogenesis and flowering time. Component ot the CUL4-RBX1-DDB1-PRL1 E3 ubiquitin-protein ligase complex which mediates ubiquitination and subsequent degradation of AKIN10. Component of the CUL4-RBX1-DDB1-DWA1/DWA2 E3 ubiquitin-protein ligase complex that acts as negative regulator in abscisic acid (ABA) signaling and may target ABI5 for degradation. Protein modification; protein ubiquitination. Interacts with COP10, CSN3, CSN4, CSN5, CSN8, DDB1A, DDB1B, DDB2, DET1 and RBX1. Ubiquitous. Neddylated (rubylated). Deneddylated via its interaction with the COP9 signalosome (CSN) complex. Small plants with mishaped cotyledons and leaves. Reduction of the number and the size of lateral roots. Increased sensitivity to sugar, cytokinin and abscisic acid (ABA). Early flowering under short day (SD) conditions. Belongs to the cullin family. Truncated N-terminus.