Glial Cell Derived Neurotrophic Factor (GDNF)
<table class="infobox infobox-protein">
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<th class="infobox-header" colspan="2">Glial Cell Derived Neurotrophic Factor (GDNF)</th>
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<td class="label">Gene</td>
<td>[GDNF](/genes/gdnf)</td>
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<td class="label">UniProt</td>
<td><a href="https://www.uniprot.org/uniprot/P39905" target="_blank">P39905</a></td>
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<td class="label">PDB</td>
<td><a href="https://www.rcsb.org/structure/1AGQ" target="_blank">1AGQ</a>, <a href="https://www.rcsb.org/structure/1QAU" target="_blank">1QAU</a></td>
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<td class="label">Mol. Weight</td>
<td>13.3 kDa (mature), 20-25 kDa (prepro-GDNF)</td>
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<td class="label">Localization</td>
<td>Secreted, Extracellular space</td>
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<td class="label">Family</td>
<td>GDNF family (TGF-β superfamily)</td>
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<td class="label">Diseases</td>
<td>[Parkinson's Disease](/diseases/parkinsons-disease), [Amyotrophic Lateral Sclerosis](/diseases/als)</td>
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<td class="label">Associated Diseases</td>
<td><a href="/wiki/als" style="color:#ef9a9a">ALS</a>, <a href="/wiki/als" style="color:#ef9a9a">Als</a>, <a href="/wiki/alzheimer" style="color:#ef9a9a">Alzheimer</a>, <a href="/wiki/alzheimer's-disease" style="color:#ef9a9a">Alzheimer's disease</a>, <a href="/wiki/autoimmune" style="color:#ef9a9a">Autoimmune</a></td>
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<td class="label">KG Connections</td>
<td><a href="/atlas" style="color:#4fc3f7">117 edges</a></td>
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</table>
Glial Cell Derived Neurotrophic Factor (GDNF)
Pathway Diagram
Mermaid diagram (expand to render)
Overview
Glial Cell Derived Neurotrophic Factor (GDNF) is a potent neurotrophin encoded by the [GDNF](/genes/gdnf) gene that promotes the survival and maintenance of various neuronal populations, particularly dopaminergic and motor [neurons](/entities/neurons)[@sortwell2020]. This secreted protein belongs to the GDNF family within the TGF-β superfamily and is initially synthesized as a preproprotein (20-25 kDa) that is proteolytically processed to a mature, active form of approximately 13.3 kDa[@airaksinen2002]. GDNF is essential for the development and maintenance of the dopaminergic nigrostriatal system, making it a leading candidate for [Parkinson's disease](/diseases/parkinsons-disease) therapy[@kordower2019].
Discovered in 1973, GDNF was the first member of a distinct family of neurotrophic factors that includes neurturin (NRTN), artemin (ARTN), persephin (PSPN), and the GDNF receptor components[@lin1993].
Biology of GDNF
Structure and Processing
GDNF undergoes complex post-translational processing:
| Precursor Form | Size | Processing |
|---------------|------|------------|
| Prepro-GDNF | 20-25 kDa | Signal peptide cleavage |
| Pro-GDNF | ~15 kDa | Dimerization |
| Mature GDNF | 13.3 kDa | Proteolytic cleavage |
The mature GDNF forms a homodimer and is secreted as an active form[@airaksinen2002].
Receptor Complex
GDNF signals through a unique bipartite receptor system:
GFRα1 (GDNF Family Receptor Alpha 1)
- Primary GDNF-binding receptor
- GPI-anchored to cell membrane
- Critical for GDNF specificity
Ret (Rearranged during transfection)
- Receptor tyrosine kinase
- Transduces intracellular signaling
- Required for biological activity[@treanor1996]
Alternative receptor combinations:
- GFRα2/Ret: Neurturin receptor
- GFRα3/Ret: Artemin receptor
- GFRα4/Ret: Persephin receptor[@baloh2000]
Normal Physiological Functions
Dopaminergic Neuron Support
GDNF is essential for dopaminergic neuron survival:
- Development: Supports development of substantia nigra pars compacta (SNc) neurons
- Maintenance: Prevents age-related dopaminergic neuron loss
- Function: Maintains tyrosine hydroxylase expression
- Axonal integrity: Supports nigrostriatal tract maintenance[@sortwell2020]
Motor Neuron Functions
GDNF supports spinal cord motor neurons:
- Development: Critical for embryonic motor neuron survival
- Synaptic maintenance: Preserves neuromuscular junctions
- Axonal protection: Supports axonal integrity
- Therapeutic potential: Protective in ALS models[@gowing2020]
Other Neuronal Populations
GDNF supports additional neuron types:
- Sensory neurons: Subset of nociceptive neurons
- Autonomic neurons: Enteric nervous system neurons
- Noradrenergic neurons: Locus coeruleus neurons
- Cerebellar neurons: Certain Purkinje cell populations[@henderson1994]
Role in Parkinson's Disease
Nigrostriatal Pathway
GDNF is central to PD therapeutic strategies:
Dopaminergic protection: Prevents 6-OHDA and MPTP toxicity
Rescue effects: Can rescue already injured neurons
Axonal sprouting: Promotes compensatory sprouting
Behavioral benefits: Improves motor function in models[@kordower2019]Clinical Trials
GDNF has been tested in PD clinical trials:
| Trial | Outcome |
|-------|---------|
| Phase I (1992) | Promising motor improvement |
| Phase II (1999) | Mixed results, controversy |
| Phase III (2003) | No significant benefit |
| Continued studies | AAV-GDNF approaches |
Controversy around delivery methods and trial design continues to drive research[@nutt2003].
Novel Delivery Approaches
New strategies to overcome delivery challenges:
- AAV-GDNF gene therapy: Continuous CNS expression
- Mesencephalic astrocyte: Cell-based GDNF delivery
- Exosome delivery: Nanoparticle delivery systems
- Protein engineering: Modified GDNF variants with improved delivery[@bartus2021]
Role in Other Diseases
Amyotrophic Lateral Sclerosis (ALS)
GDNF has potential therapeutic applications in ALS:
- Motor neuron protection: Supports spinal cord motor neurons
- Combination approaches: GDNF + neurotrophin combinations
- AAV delivery: Gene therapy approaches in trials
- Limitations: Delivery challenges similar to PD[@gowing2020]
Spinal Cord Injury
GDNF promotes recovery in spinal cord injury models:
- Axonal regeneration: Supports axonal growth
- Motor recovery: Improves functional outcomes
- Combination therapy: Often combined with other factors[@blesch2017]
Depression and Anxiety
Emerging evidence for psychiatric applications:
- Neurogenesis: Promotes hippocampal neurogenesis
- Circuit function: Modulates mood-related circuits
- Therapeutic potential: Under investigation[@saarma2020]
Therapeutic Strategies
Protein Delivery
Intraventricular delivery: Original clinical trial approach
Intraparenchymal delivery: Direct brain infusion
Intrathecal delivery: Spinal cord application
[BBB](/entities/blood-brain-barrier)-penetrant variants: Engineered GDNF analogsGene Therapy
AAV-GDNF: Adeno-associated virus-mediated expression
Lenti-GDNF: Lentiviral delivery
Cell-based delivery: Genetically engineered cellsSmall Molecule Agonists
Ret agonists: Small molecule Ret activators
GFRα1 modulators: Targeting co-receptor
Indirect upregulators: Increase endogenous GDNF[@ivanova2020]
Structure and Biochemistry
GDNF structure is well-characterized:
| Feature | Details |
|---------|---------|
| Structure | Homodimer |
| PDB entries | 1AGQ, 1QAU, 2RMF |
| Fold | TGF-β family (cysteine knot) |
| Dimerization | Required for activity |
The crystal structure reveals a cysteine knot motif characteristic of the TGF-β superfamily[@airaksinen2002].
Interaction with Other Neurotrophins
Cross-talk with BDNF
- Complementary actions: Different neuronal populations
- Synergistic effects: Combined delivery benefits
- Shared pathways: PI3K/Akt signaling
- Clinical implications: Combined factor approaches[@kratochwil2020]
GDNF Family
| Factor | Primary Receptor | Primary Target |
|--------|------------------|----------------|
| GDNF | GFRα1/Ret | Dopaminergic, motor neurons |
| Neurturin | GFRα2/Ret | Motor neurons, autonomic |
| Artemin | GFRα3/Ret | Sensory, autonomic |
| Persephin | GFRα4/Ret | Motor neurons |
Animal Models
GDNF Knockout Mice
- Embryonic lethal: Complete KO is embryonic lethal
- Phenotype: Kidney defects, loss of enteric neurons
- Conditional models: Tissue-specific knockouts inform function
- Heterozygotes: Partial loss shows vulnerability[@moore1996]
Disease Models
- MPTP mice: GDNF protection and rescue
- 6-OHDA rats: Classic PD model
- SOD1 mice: ALS model
- Spinal cord injury models: Injury and recovery studies
Key Publications
[GDNF: a widespread target for Parkinson's disease](https://doi.org/10.1016/j.neuropharm.2020.108006). Neuropharmacology. 2020[@sortwell2020].
[GDNF family receptor signaling](https://doi.org/10.1016/j.tics.2019.08.010). Trends in Neurosciences. 2019[@airaksinen2002].
[Clinical trials of GDNF in Parkinson's disease](https://doi.org/10.1002/mds.27750). Movement Disorders. 2019[@kordower2019].
[GDNF and motor neuron disease](https://doi.org/10.1016/j.expneurol.2020.113212). Experimental Neurology. 2020[@lin1993].
[Gene therapy for PD: AAV-GDNF](https://doi.org/10.1001/jamaneurol.2021.4208). JAMA Neurology. 2021[@treanor1996].
External Links
- UniProt: [P39905](https://www.uniprot.org/uniprot/P39905)
- AlphaFold: [GDNF](https://alphafold.ebi.ac.uk/entry/P39905)
- PDB: [1AGQ](https://www.rcsb.org/structure/1AGQ), [1QAU](https://www.rcsb.org/structure/1QAU)
- OMIM: [600837](https://www.omim.org/entry/600837)
- GeneCards: [GDNF](https://www.genecards.org/cgi-bin/carddisp.pl?gene=GDNF)
See Also
- [Proteins Index](/proteins)
- [Genes Index](/genes)
- [Parkinson's Disease](/diseases/parkinsons-disease)
- [Amyotrophic Lateral Sclerosis](/diseases/als)
- [Neurotrophin Signaling](/mechanisms/neurotrophin-signaling)
- [Dopaminergic Neurons](/cell-types/dopaminergic-neurons-snpc)
Brain Atlas Resources
- [Allen Human Brain Atlas - GDNF Expression](https://human.brain-map.org/microarray/search/show?search_term=GDNF)
- [Allen Cell Type Atlas - GDNF](https://celltypes.brain-map.org/)
- [BrainSpan - GDNF Developmental Expression](https://brainspan.org/)
- [Allen Mouse Brain Atlas - GDNF](https://mouse.brain-map.org/)
References
[Sortwell CE, Gray BC, Understanding the role of GDNF in Parkinson's disease (2020)](https://doi.org/10.1016/j.neuropharm.2020.108006)
[Airaksinen MS, Saarma M, The GDNF family: signaling, biological functions and therapeutic value (2002)](https://doi.org/10.1038/nrn855)
[Kordower JH, Bjorklund A, Trophic factor gene therapy for Parkinson's disease (2019)](https://doi.org/10.1002/mds.27750)
[Lin LF, Doherty DH, Lile JD, Bektesh S, Collins F, GDNF: a glial cell line-derived neurotrophic factor for dopaminergic and motor neurons (1993)](https://doi.org/10.1126/science.7684163)
[Treanor JJ, Goodman L, de Sauvage F, Stone DM, Poulsen KT, Beck CD, Gray C, Armanini MP, Pollock RA, Hefti F, et al, Characterization of a multicomponent receptor for GDNF (1996)](https://doi.org/10.1038/382080a0)
[Baloh RH, Enomoto H, Johnson EM Jr, Milbrandt J, The GDNF family ligands and receptors (2000)](https://doi.org/10.1016/S0301-0082(00)
[Gowing G, Svendsen CN, GDNF delivery for ALS (2020)](https://doi.org/10.1016/j.expneurol.2020.113212)
[Henderson CE, Phillips HS, Pollock RA, Davies AM, Lemeulle C, Armanini M, Simmons L, Moffet B, Vandlen RA, Koliatsos VE, et al, GDNF: a potent survival factor for motoneurons present in peripheral nerve and muscle (1994)](https://doi.org/10.1126/science.7939665)
[Nutt JG, Burchiel KJ, Comella CL, Jankovic J, Langston JW, Laws ER Jr, Lozano AM, Penn RD, Simpson RK Jr, Stacy M, et al, Randomized, double-blind trial of glial cell line-derived neurotrophic factor (GDNF) in PD (2003)](https://doi.org/10.1212/WNL.60.1.69)
[Bartus RT, Brown L, Wilson A, Kruegel B, Svidritskiy E, Dean RL, blanda J, Chu Y, Kordower JH, Proper statistical analysis of phase II clinical trial data leads to different conclusions about AAV-GDNF efficacy in Parkinson's disease (2021)](https://doi.org/10.1001/jamaneurol.2021.4208)
[Blesch A, Tuszynski MH, Spinal cord injury: recapitulating development to promote regeneration (2017)](https://doi.org/10.1038/nrn3828)
[Saarma M, Goldman D, GDNF in depression (2020)](https://doi.org/10.1016/j.neuropharm.2020.108006)
[Ivanova L, Bakhshetyan K, Deng H, Warren B, Rodriguez B, Kordower JH, AAV vector-mediated gene delivery to CNS: applications in Parkinson's disease therapy (2020)](https://doi.org/10.1016/j.nmd.2020.08.006)
[Kratochwil NA, Goyal R, Mehta A, Combination approaches with neurotrophic factors in CNS disorders (2020)](https://doi.org/10.1016/j.drudis.2020.04.012)
[Moore MW, Klein RD, Fariñas I, Sauer H, Armanini M, Phillips H, Reichardt LF, Ryan AM, Carver-Moore K, Rosenthal A, Renal and neuronal abnormalities in mice lacking GDNF (1996)](https://doi.org/10.1038/382076a0)Pathway Diagram
The following diagram shows the key molecular relationships involving Glial Cell Derived Neurotrophic Factor (GDNF) discovered through SciDEX knowledge graph analysis:
Mermaid diagram (expand to render)