MITF-A is an isoform of MITF (microphthalmia-associated transcription factor), a transcription factor that contains both basic helix-loop-helix and leucine zipper structural features. It regulates the differentiation and development of melanocytes retinal pigment epithelium and is also responsible for pigment cell-specific transcription of the melanogenesis enzyme genes. Heterozygous mutations in the this gene cause auditory-pigmentary syndromes, such as Waardenburg syndrome type 2 and Tietz syndrome. MITF-A lentivirus (TET-inducible, Puro) expresses human MITF-A under the control of the Tet responsive promoter, with puromycin as a selection marker.