The MiT/TFE family of basic helix-loop-helix leucine zipper transcription factors includes MITF (microphthalmia-associated transcription factor) and related family members TFE3, TFEB and TFEC []. The transcription factors heterodimerize with each other and recognise the same DNA sequences []. They recognise and bind E-box sequences (3'-CANNTG-5').This entry represents the transcription factor E3 (TFE3). In association with TFEB, TFE3 activates the expression of CD40L in T-cells, thereby playing a role in T-cell-dependent antibody responses in activated CD4+ T-cells and thymus-dependent humoral immunity. It also has also a role in osteoclast development []. TFE3 specifically recognises the MUE3 box, a subset of E-boxes, present in the immunoglobulin enhancer []. For efficient DNA-binding, TFE3 requires dimerisation with itself or with another MiT/TFE family member, such as TFEB or MITF.
