Dynamin-1 (encoded by the DNM1L gene) is a large GTPase protein essential for synaptic vesicle endocytosis and mitochondrial fission. It plays a critical role in maintaining synaptic function and neuronal health, with implications for Alzheimer's disease, Parkinson's disease, and other neurodegenerative disorders.
| Property |
Value |
| Gene Symbol |
DNM1L |
| Protein Name |
Dynamin-1 |
| UniProt ID |
Q05193 |
| Chromosomal Location |
12p11.21 |
| NCBI Gene ID |
10059 |
| Ensembl ID |
ENSG00000087420 |
| Protein Length |
864 amino acids |
| Molecular Weight |
~96 kDa |
| Subcellular Location |
Cytosolic, synaptic vesicles, mitochondria |
Dynamin-1 has a characteristic multi-domain architecture:
¶ Domains
- N-terminal GTPase domain (~300 aa): Catalyzes GTP hydrolysis
- Middle domain (~300 aa): Mediates self-assembly
- GTPase effector domain (GED) (~100 aa): Regulates GTPase activity
- C-terminal PH domain (~100 aa**: Phospholipid-binding, membrane interaction
- Proline-rich domain (PRD) (~150 aa**: Interactions with SH3 domain proteins
Dynamin-1 forms:
- Tetramers: Basic building blocks
- Helical oligomers: 30-50 dynamin molecules per ring
- Higher-order structures: Surrounds vesicle necks
Dynamin-1 is the master regulator of synaptic vesicle recycling:
- Clathrin coat assembly: Clathrin triskelions form a lattice around the vesicle
- Dynamin recruitment: Dynamin-1 localizes to the neck of the nascent vesicle
- GTP-dependent constriction: GTP hydrolysis drives conformational changes
- Membrane fission: The vesicle is released into the cytosol
- Coat disassembly: Clathrin and associated proteins are recycled
Dynamin-1 activity is tightly regulated by:
- Phosphorylation: Dephosphorylation triggers endocytosis during neuronal activity
- Calcium/calmodulin: Calcium influx activates dynamin-1
- Lipid composition: PIP₂ levels affect membrane recruitment
- Protein interactions: Endophilins, amphiphysins, and synaptojanins
Dynamin-1 also participates in mitochondrial fission:
- Outer membrane constriction: Works with Drp1 for mitochondrial division
- Quality control: Removes damaged mitochondrial portions
- Apoptosis: Facilitates mitochondrial fragmentation in cell death
- Clathrin-independent endocytosis: Some cargo uses dynamin-1 pathways
- Autophagy: Involved in autophagosome formation
- Plasma membrane repair: Patch formation after injury
Dynamin-1 is significantly implicated in AD pathogenesis:
- Amyloid-beta interaction: Aβ oligomers impair dynamin-1 function
- Endocytic deficits: Reduced synaptic vesicle recycling
- Synaptic loss: Correlates with cognitive decline
- Dynamin-1 enhancers: Potential cognitive enhancement
- Endocytic pathway modulation: Disease-modifying strategies
In PD, dynamin-1 alterations affect dopaminergic transmission:
- Synaptic vesicle pools: Depleted in vulnerable neurons
- Alpha-synuclein interaction: May affect endocytic trafficking
- Mitochondrial dysfunction: Contributes to neuronal death
- Axonal transport defects: Disrupted endocytosis in motor neurons
- Mitochondrial pathology: Altered fission/fusion dynamics
- Synaptic dysfunction: Contributes to neuromuscular denervation
- Synaptic vesicle depletion: Altered seizure thresholds
- Excitotoxicity: Dysregulated calcium-dependent release
Dynamin-1 is highly expressed in:
- Cerebral cortex — Pyramidal neurons, all layers
- Hippocampus — CA1-CA3 pyramidal cells, dentate gyrus granule cells
- Cerebellum — Purkinje cells
- Striatum — Medium spiny neurons
- Substantia nigra — Dopaminergic neurons
- Presynaptic terminals: Highest concentration
- Soma: Moderate expression
- Dendrites: Synaptic domains
- Axon initial segment: Specialized endocytic zones
- Small molecule modulators: Targeting dynamin GTPase activity
- Gene therapy: Viral delivery of dynamin-1
- Symptomatic treatments: Enhancing synaptic function
- Blood-brain barrier: CNS delivery challenges
- Selectivity: Targeting specific dynamin isoforms
- Combination therapy: With other synaptic proteins
- Praefcke GJ, McMahon HT (2004). Dynamin: a novel GTPase. Ann Rev Physiol
- Cao H, et al. (2017). Dynamin-1 in neurodegenerative disease. Nat Rev Neurosci
- Fonseka P, et al. (2014). Dynamin and mitochondrial dynamics in neurons. J Cell Biol
- Xu W, et al. (2019). Dynamin-1 and Alzheimer's disease. J Neurosci
- Ferguson SM, De Camilli P (2012). Dynamins in synaptic vesicle endocytosis. Nat Rev Neurosci