To visualize TGFb response across melanoma development, single cell Tg(mitfa:BRAFV600E);p53-/-;mitfa-/- embryos stably expressing TIE:EGFP were injected with an empty MiniCoopR vector (MCR:MCS) containing the mitfa minigene to generate melanomas. The gene discussed is TGFB1; the disease is melanoma.