||TFE3 (transcription factor binding to IGHM enhancer 3) encodes a basic helix-loop-helix domain-containing transcription factor that binds MUE3-type E-box sequences in the promoter of genes. The encoded protein promotes the expression of genes downstream of transforming growth factor beta (TGF-beta) signaling. TFE3 may be involved in chromosomal translocations in renal cell carcinomas and other cancers, resulting in the production of fusion proteins. Translocation partners include PRCC (papillary renal cell carcinoma， NONO (non-POU domain containing, octamer-binding， and ASPSCR1 (alveolar soft part sarcoma chromosome region, candidate 1， among other genes. Alternative splicing results in multiple transcript variants.