TFE3 and melanoma: However, Verastegui et al.105 found no detectable heterodimerization between MITF and TFE3 in B16-F10 melanoma, and genetic analysis of MITF family mutant mice indicated that heterodimeric interactions are not essential for MITF-TFE function.106 In general, the data are more consistent with expression, rather than dimerization, playing a key role in their differential activities.