MGAT5 and melanoma: For this purpose, we stably expressed human GnT-V fused with a Halo7 tag (GnT-V-Halo) in B16 cells (a murine melanoma cell line), and we confirmed by in vitro enzyme assays that GnT-V-Halo retained enzyme activity (Supplementary Fig. 4a, b), excluding that addition of the Halo-tag inhibited GnT-V functions.