basic Helix-Loop-Helix-zipper (bHLHzip) domain found in the microphthalmia-associated transcription factor family (MITF) family
The MITF (also known as microphthalmia-TFE, or MiT) family is a small family that contain a basic helix loop helix domain associated with a leucine zipper (bHLHZip). The MITF family comprises four genes in mammals (MITF, TFE3, TFEB, and TFEC); each gene has different functions. MITF is involved in neural crest melanocytes development as well as the pigmented retinal epithelium. TFEB is required for vascularization of the mouse placenta. TFE3 is involved in B cell function. TFEC regulates gene expression in macrophages. The MITF family can form homodimers or heterodimers with each other but not with other bHLH or bHLHzip proteins.