Employing immortalized human primary melanocytes and the highly pigmented human melanoma cell line SK-Mel-30, Cao et al., showed that suppression of TSC1 or TSC2 expression reduces pigmentation, decreases tyrosinase activity and lowers the levels of MITF and its downstream pigment-related target genes: TYR, TYRP1, PMEL and DCT. Here, TYR is linked to melanoma.