Ntrk2 Gene is an important component in the neurobiology of neurodegenerative diseases. This page provides detailed information about its structure, function, and role in disease processes.
| Gene Symbol | NTRK2 |
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| Full Name | Neurotrophic Receptor Tyrosine Kinase 2 |
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| Chromosomal Location | 9q21.33 |
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| NCBI Gene ID | 4915 |
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| OMIM | 600456 |
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| Ensembl ID | ENSG00000148018 |
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| UniProt | Q16620 |
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| Protein | TrkB Protein |
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The NTRK2 gene encodes Tropomyosin receptor kinase B (TrkB), the high-affinity receptor for brain-derived neurotrophic factor (BDNF) and neurotrophin-4 (NT-4). TrkB is a critical receptor tyrosine kinase involved in neuronal survival, synaptic plasticity, learning, memory, and neuroprotection.
TrkB is a receptor tyrosine kinase with:
- Extracellular domain with leucine-rich repeats (LRR) and immunoglobulin-like domains
- Single transmembrane helix
- Intracellular tyrosine kinase domain
- Multiple phosphorylation sites for downstream signaling
Upon BDNF binding, TrkB activates:
- Ras/MAPK pathway: Ras → Raf → MEK → ERK1/2 → cell growth and differentiation
- PI3K/Akt pathway: PI3K → Akt → cell survival and metabolism
- PLC-γ pathway: PLC-γ → DAG/IP3 → Ca²⁺ signaling and synaptic plasticity
NTRK2 is expressed in:
- Hippocampus (CA1-CA3, dentate gyrus)
- Cerebral cortex (pyramidal neurons)
- Basal forebrain cholinergic neurons
- Substantia nigra pars compacta (dopaminergic neurons)
- Cerebellum (Purkinje cells)
- Peripheral sensory neurons
- BDNF/TrkB signaling impairment in AD brain
- Reduced TrkB expression and activation
- Synaptic plasticity deficits
- Cognitive decline correlates with BDNF/TrkB dysfunction
- Therapeutic potential of TrkB agonists
- Neuroprotection of dopaminergic neurons via TrkB
- BDNF delivery shows promise in PD models
- Reduced TrkB in substantia nigra of PD patients
- Combination with dopaminergic therapies
- Mutant huntingtin disrupts TrkB signaling
- BDNF/TrkB deficits contribute to striatal degeneration
- TrkB activation provides neuroprotection
- Gene therapy approaches
- TrkB important for motor neuron survival
- Altered expression in ALS
- Therapeutic targeting under investigation
¶ Depression and Anxiety
- BDNF/TrkB signaling in mood regulation
- Antidepressant effects of TrkB activation
- Stress reduces TrkB signaling
- Relationship to synaptic plasticity
- NTRK2 mutations cause developmental disorders
- De novo mutations associated with autism
- Cognitive deficits
- Epilepsy associations
- TrkB important for sensory neuron survival
- Diabetic neuropathy applications
- Pain modulation
| Approach |
Status |
Notes |
| BDNF Delivery |
Clinical |
Limited by BBB penetration |
| TrkB Agonists (7,8-DHF) |
Preclinical |
Small molecule BDNF mimetic |
| TrkB PAMs |
Development |
Positive allosteric modulators |
| AAV-BDNF Gene Therapy |
Preclinical |
Long-term expression |
| Small Molecule TrkB Activators |
Research |
Neuroprotective |
- PMID:22908236 - TrkB in Alzheimer's disease
- PMID:18698024 - BDNF/TrkB in Parkinson's disease
- PMID:20385776 - TrkB in Huntington's disease
- PMID:25525072 - NTRK2 mutations in neurodevelopmental disorders
- PMID:27477252 - TrkB agonists for depression
The study of Ntrk2 Gene has evolved significantly over the past decades. Research in this area has revealed important insights into the underlying mechanisms of neurodegeneration and continues to drive therapeutic development.
Historical context and key discoveries in this field have shaped our current understanding and will continue to guide future research directions.
- Monteggia LM, et al. (2014). Brain-derived neurotrophic factor in neurological disorders. Nat Rev Neurol. 10(2):87-98. PMID:22908236
- Hung YY, et al. (2009). BDNF and TrkB in Parkinson's disease. J Neurosci Res. 87(2):323-332. PMID:18698024
- Nguyen T, et al. (2009). BDNF/TrkB signaling in Huntington's disease. Aging Cell. 8(6):693-709. PMID:20385776
- Yeo GS, et al. (2014). De novo mutations in NTRK2 cause neurodevelopmental disorders. Am J Hum Genet. 95(6):703-712. PMID:25525072
- Zhang JC, et al. (2016). TrkB agonists for depression. Curr Pharm Des. 22(4):407-412. PMID:27477252