RBX1RING-box protein 1 is a protein that in humans is encoded by the RBX1 gene.FunctionThis gene encodes an evolutionarily conserved protein that interacts with cullins. The protein plays a unique role in the ubiquitination reaction by heterodimerizing with cullin-1 to catalyze ubiquitin polymerization. It also may be involved in the regulation of protein turn-over.InteractionsRBX1 has been shown to interact with: CAND1, CUL1, CUL2, CUL4A, CUL5 CUL7, DCUN1D1, and P70-S6 Kinase 1.