TFEB (Transcription Factor EB) is a key member of the MiT/TFE family, which also includes TFE3, TFEC, and MITF. TFEB features a basic helix-loop-helix (bHLH) domain and is primarily localized in the nucleus. It is a major regulator of autophagy and lysosomal gene expression, facilitating cellular adaptation to nutrition and stress by regulating these genes. TFEB activity and localization are modulated by various signaling pathways, such as mTOR. Its gene expression varies across tissues, and mutations may lead to metabolic diseases or other pathological conditions.