Cullins assemble a potentially large number of ubiquitin ligases by binding to the RING protein ROC1 to catalyse polyubiquitination, as well as binding to various specificity factors to recruit substrates. Cullin 7 is a component of E3 ubiquitin ligase complexes, which mediate the ubiquitination and subsequent proteasomal degradation of target proteins. Cullin 7 seems to be involved proteosomal degradation of proteins involved in endothelial proliferation and/or differentiation. Cullin 7 is part of a SCF-like complex consisting of CUL7, RBX1, SKP1, FBXW8 and GLMN isoform 1. Cullin 7 interacts with a complex of SKP1 and FBXW8, but not with SKP1 alone.