We confirmed that Fbxl8 forms an SCF complex in vivo and in vitro (Figs. 1a and S1C) and subsequently demonstrated that endogenous Fbxl8 binds to cyclin D3 in NIH3T3 cells and Burkitt’s lymphoma, Raji cells (Figs. 1b and S1D–E). This evidence concerns the gene KITLG and Burkitt lymphoma.