TFE3 (Transcription Factor Binding to IGHM Enhancer 3) is a member of the MiT/TFE family of basic helix-loop-helix leucine zipper (bHLH-LZ) transcription factors, alongside TFEB, MITF, and TFEC. TFE3 is a master regulator of lysosomal biogenesis, autophagy, and cellular stress responses. In the central nervous system, TFE3 activates transcription of genes encoding lysosomal enzymes, autophagy machinery, and lipid catabolism factors. Impairment of TFE3 nuclear translocation — due to chronic mTORC1 hyperactivation or sequestration by protein aggregates — contributes to the lysosomal dysfunction and autophagy failure that underlies Alzheimer's disease, Parkinson's disease, and lysosomal storage disorders with neurodegeneration.
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| Full Name | Transcription Factor Binding to IGHM Enhancer 3 |
| Gene Symbol | TFE3 |
| Chromosomal Location | Xp11.23 |
| NCBI Gene ID | [7030](https://www.ncbi.nlm.nih.gov/gene/7030) |
| Ensembl ID | [ENSG00000068323](https://www.ensembl.org/Homo_sapiens/Gene/Summary?g=ENSG00000068323) |
| UniProt ID | [P19532](https://www.uniprot.org/uniprot/P19532) |
| Protein | [TFE3 Protein](/proteins/tfe3-protein) |
| Associated Diseases | [AD](/diseases/alzheimers-disease), [PD](/diseases/parkinsons-disease), [HD](/diseases/huntingtons-disease), Lysosomal storage disorders |
TFE3 binds Coordinated Lysosomal Expression and Regulation (CLEAR) elements in the promoters of over 400 lysosomal and autophagy genes:
- Lysosomal hydrolases: CTSD, CTSB, CTSL, HEXA, HEXB, GLA
- Lysosomal membrane proteins: LAMP1, LAMP2, MCOLN1, ATP6V0D1, ATP6V1H
- Autophagy regulators: BECN1, ATG9A, ATG16L1, WIPI1, ULK1
- Lipid catabolism: PPARGC1A, LIPA, ASAH1
TFE3, in coordination with TFEB, drives the transcriptional program for all forms of autophagy:
- Macroautophagy: Upregulation of ATG genes for autophagosome formation
- Chaperone-mediated autophagy (CMA): Induction of LAMP2A and HSC70
- Mitophagy: Upregulation of PINK1, BNIP3L/NIX, and FUNDC1
- Aggrephagy: Induction of SQSTM1/p62, NBR1, and OPTN autophagy receptors
Under nutrient-replete conditions, mTORC1 phosphorylates TFE3 at Ser321, creating a 14-3-3 binding site that sequesters TFE3 in the cytoplasm. Upon starvation, lysosomal stress, or mTORC1 inhibition:
- Calcineurin (activated by lysosomal calcium release through MCOLN1) dephosphorylates TFE3
- Dephosphorylated TFE3 escapes 14-3-3 binding and translocates to the nucleus
- Nuclear TFE3 activates CLEAR element-containing promoters
- This creates a feedback loop: TFE3 induces lysosomal biogenesis to restore lysosomal function
TFE3 and TFEB share over 70% homology in their bHLH-LZ domains and bind identical CLEAR elements. They form homo- and heterodimers. In the brain:
- Both are expressed in neurons, microglia, astrocytes, and oligodendrocytes
- Double knockout of Tfeb and Tfe3 in neurons causes severe lysosomal storage and neurodegeneration in mice, while single knockouts show partial phenotypes
- TFE3 may partially compensate for TFEB loss and vice versa
- Amyloid-beta oligomers chronically activate mTORC1 in neurons, trapping TFE3 in the cytoplasm and impairing autophagy
- TFE3 nuclear localization is reduced in AD patient hippocampal neurons compared to age-matched controls
- Overexpression of constitutively active TFE3 (S321A) in APP/PS1 mice reduces amyloid plaque burden by enhancing lysosomal degradation of Aβ
- TFE3-driven autophagy is required for clearance of tau aggregates; TFE3 deficiency exacerbates tauopathy
- α-Synuclein aggregates impair lysosomal function and trap TFE3/TFEB in the cytoplasm
- LRRK2 G2019S mutations increase mTORC1 activity, reducing TFE3 nuclear translocation
- TFE3 overexpression in dopaminergic neurons rescues α-synuclein-induced toxicity by enhancing autophagic clearance
- GBA1 mutations reduce glucocerebrosidase activity, causing lysosomal stress that activates TFE3 as a compensatory response
- Mutant huntingtin protein sequesters TFE3 in cytoplasmic aggregates, preventing nuclear translocation
- TFE3 activation (via mTORC1 inhibitors or genetic approaches) reduces mutant huntingtin aggregation in HD models
- HTT polyQ expansion disrupts the TFE3-14-3-3 interaction, paradoxically impairing rather than enhancing TFE3 nuclear import
- TFE3 constitutive activation occurs in multiple LSDs (Pompe, Gaucher, Niemann-Pick C) as a compensatory response to lysosomal dysfunction
- However, this activation is often insufficient to overcome the primary enzymatic deficiency
- Gene therapy strategies combining enzyme replacement with TFE3 overexpression show synergistic effects
- Neurons: Moderate expression; TFE3 and TFEB cooperate to maintain neuronal lysosomal homeostasis
- Microglia: High expression; TFE3 regulates phagocytic capacity and inflammatory gene expression
- Astrocytes: Moderate expression; involved in astrocytic autophagy and lipid metabolism
- Oligodendrocytes: Moderate expression; TFE3 supports myelin lipid turnover
Allen Brain Atlas data shows TFE3 expression enriched in hippocampus, cortex, and cerebellum — regions with high metabolic and autophagic demands.
- Rapamycin/Everolimus: mTORC1 inhibition promotes TFE3/TFEB nuclear translocation; rapamycin shows neuroprotective effects in AD and PD models
- Torin1/2: ATP-competitive mTOR inhibitors with stronger TFE3 activation than rapalogs
- CCI-779 (Temsirolimus): mTORC1 inhibitor that promotes autophagy in neurodegenerative models
- Trehalose: Disaccharide that activates TFEB/TFE3 through mTOR-independent mechanisms; neuroprotective in multiple models
- MCOLN1 agonists (ML-SA1): Activate lysosomal calcium release, promoting calcineurin-dependent TFE3 dephosphorylation
- Curcumin analogs: Activate TFEB/TFE3 nuclear translocation in neurons
- AAV-mediated TFE3 or TFEB delivery to neurons reduces pathology in AD, PD, and HD mouse models
- Constitutively nuclear TFE3 (S321A) variants provide stronger and sustained activation