DARS2 (Aspartyl-tRNA Synthetase 2, Mitochondrial) is a critical mitochondrial aminoacyl-tRNA synthetase that plays an essential role in mitochondrial protein synthesis. This enzyme is responsible for the ATP-dependent attachment of aspartic acid to its cognate mitochondrial tRNA (tRNA^Asp), which is fundamental for the translation of all 13 mitochondrial-encoded proteins [1](https://pubmed.ncbi.nlm.nih.gov/21889355/). DARS2 is encoded by the DARS2 gene located on chromosome 12q24.1 and is ubiquitously expressed with highest levels in tissues with high mitochondrial demand, including the brain, heart, and skeletal muscle [2](https://pubmed.ncbi.nlm.nih.gov/22550328/). [@perez2018]
DARS2 (Aspartyl-tRNA Synthetase 2, Mitochondrial) is a critical mitochondrial aminoacyl-tRNA synthetase that plays an essential role in mitochondrial protein synthesis. This enzyme is responsible for the ATP-dependent attachment of aspartic acid to its cognate mitochondrial tRNA (tRNA^Asp), which is fundamental for the translation of all 13 mitochondrial-encoded proteins [1](https://pubmed.ncbi.nlm.nih.gov/21889355/). DARS2 is encoded by the DARS2 gene located on chromosome 12q24.1 and is ubiquitously expressed with highest levels in tissues with high mitochondrial demand, including the brain, heart, and skeletal muscle [2](https://pubmed.ncbi.nlm.nih.gov/22550328/). [@perez2018]
The mitochondrial genetic system is distinct from the cytosolic translation machinery, requiring specialized components including mitochondrial aminoacyl-tRNA synthetases (mtaaRSs). DARS2 belongs to this unique family of enzymes that have evolved to function within the mitochondrial matrix and accurately translate the mitochondrial genome [3](https://pubmed.ncbi.nlm.nih.gov/23283301/). [@ramon2014]
<div class="infobox infobox-protein">
<table>
<tr><th colspan="2">DARS2 Protein</th></tr>
<tr><td>Protein Name</td><td>Aspartyl-tRNA Synthetase 2, Mitochondrial</td></tr>
<tr><td>Gene</td><td>[DARS2](/genes/dars2)</td></tr>
<tr><td>UniProt</td><td>[Q9NXE1](https://www.uniprot.org/uniprot/Q9NXE1)</td></tr>
<tr><td>Location</td><td>Mitochondria (matrix)</td></tr>
<tr><td>Function</td><td>Mitochondrial tRNA aminoacylation</td></tr>
<tr><td>MW</td><td>73.8 kDa</td></tr>
<tr><td>Structure</td><td>Homodimer</td></tr>
<tr><td>Enzyme Class</td><td>EC 6.1.1.12</td></tr>
<tr>
<td class="label">Associated Diseases</td>
<td><a href="/wiki/carcinoma" style="color:#ef9a9a">Carcinoma</a>, <a href="/wiki/tumor" style="color:#ef9a9a">Tumor</a></td>
</tr>
<tr>
<td class="label">KG Connections</td>
<td><a href="/atlas" style="color:#4fc3f7">7 edges</a></td>
</tr>
</table>
</div>
DARS2 belongs to the class II aminoacyl-tRNA synthetase family and possesses the characteristic catalytic domain found in these enzymes. Unlike their cytosolic counterparts, mitochondrial aminoacyl-tRNA synthetases have evolved unique features to function within the mitochondrial environment and recognize mitochondrial tRNAs [4](https://pubmed.ncbi.nlm.nih.gov/23625846/).
The protein contains several functional domains:
The aminoacylation reaction proceeds through a well-characterized two-step mechanism:
Step 1: Aminoacyl-adenylate formation
Aspartic acid + ATP → Asp-AMP + PPi
Step 2: tRNA Charging
Asp-AMP + tRNA^Asp → Asp-tRNA^Asp + AMP
This reaction is essential for mitochondrial translation, as the mitochondrial genetic system requires properly charged tRNAs for accurate protein synthesis. The reaction is driven forward by pyrophosphate hydrolysis [5](https://pubmed.ncbi.nlm.nih.gov/23283301/).
Mitochondria are essential for cellular energy production through oxidative phosphorylation (OXPHOS). The mitochondrial genome encodes 13 subunits of the electron transport chain complexes, along with 22 tRNAs and 2 rRNAs required for their translation [6](https://pubmed.ncbi.nlm.nih.gov/22100925/). DARS2-mediated mitochondrial translation is therefore crucial for:
Biallelic mutations in DARS2 cause a recessive disorder characterized by childhood-onset progressive leukoencephalopathy. This devastating neurological condition was first described in 2007 and is characterized by [8](https://pubmed.ncbi.nlm.nih.gov/17377065/):
Recent studies have identified DARS2 mutations as a risk factor for ALS, particularly in sporadic cases. The mechanism involves multiple pathways [10](https://pubmed.ncbi.nlm.nih.gov/33449951/):
While not directly causative, DARS2 dysfunction may contribute to Alzheimer's disease pathogenesis through multiple mechanisms [11](https://pubmed.ncbi.nlm.nih.gov/28715993/):
In PD, DARS2 may play a protective role:
Targeting DARS2 and mitochondrial translation represents a promising therapeutic approach for neurodegenerative diseases:
Compounds that improve mitochondrial translation efficiency:
AAV-mediated delivery of functional DARS2:
Agents that preserve mitochondrial function:
Compounds that enhance alternative energy pathways:
DARS2 interacts with several proteins involved in mitochondrial function:
| Partner Protein | Interaction Type | Functional Significance |
|-----------------|------------------|------------------------|
| Mitochondrial ribosome | Direct binding | tRNA channeling to ribosome |
| EF-Tu (TUFM) | Direct binding | tRNA delivery to ribosome |
| LRPPRC | Indirect | mRNA stabilization in mitochondria |
| CLPX | Direct binding | Quality control and turnover |
| Mitochondrial Hsp60 | Chaperone | Protein folding assistance |
| p32 (C1QBP) | RNA binding | Mitochondrial RNA metabolism |
Current research areas include: