| CHCHD2 - Coiled-Coil Helix Domain Containing 2 | |
|---|---|
| Gene Symbol | CHCHD2 |
| Full Name | Coiled-Coil Helix Domain Containing 2 |
| Chromosome | 7p11.2 |
| NCBI Gene ID | [84687](https://www.ncbi.nlm.nih.gov/gene/84687) |
| OMIM | [616311](https://www.omim.org/entry/616311) |
| Ensembl ID | [ENSG00000106125](https://www.ensembl.org/Homo_sapiens/Gene/Summary?g=ENSG00000106125) |
| UniProt ID | [Q9H5Q4](https://www.uniprot.org/uniprotkb/Q9H5Q4) |
| Protein Class | Mitochondrial protein |
| Associated Diseases | Parkinson's Disease (Autosomal Dominant) |
CHCHD2 (Coiled-Coil Helix Domain Containing 2) is a mitochondrial protein encoding gene that was first linked to Parkinson's disease in 2015 when loss-of-function mutations were identified in families with autosomal dominant PD[^chchd2_parkinson_2015]. The discovery added CHCHD2 to the growing list of genes implicated in familial Parkinson's disease, joining established genes like LRRK2, GBA, and SNCA.
CHCHD2 is a small mitochondrial protein localized to the intermembrane space, where it plays important roles in mitochondrial function, particularly in response to oxidative stress. The protein contains a unique coiled-coil helix domain that facilitates protein-protein interactions and may be involved in mitochondrial protein complex formation[^chchd2_function_2017].
The discovery of CHCHD2's involvement in Parkinson's disease adds to the growing list of mitochondrial genes implicated in neurodegeneration, including PINK1, PARKIN, and DJ-1. Mitochondrial dysfunction is recognized as a central pathogenic mechanism in Parkinson's disease, and CHCHD2 provides another link between this organelle and dopaminergic neuron survival.
CHCHD2 is a 182-amino acid protein characterized by[^chchd2_structure]:
CHCHD2 localizes to the mitochondrial intermembrane space, where it[^chchd2_mitoch]:
CHCHD2 participates in several mitochondrial processes[^chchd2_oxphos]:
CHCHD2 mutations cause autosomal dominant Parkinson's disease:
The pathogenic mechanisms linking CHCHD2 to PD include[^chchd2_parkinsons]:
Post-mortem studies of CHCHD2 mutation carriers show:
CHCHD2 is widely expressed with high levels in:
The high expression in dopaminergic neurons may explain the selective vulnerability in Parkinson's disease.
CHCHD2 interacts with several other Parkinson's disease genes:
| Gene | Interaction |
|---|---|
| SNCA | Synergistic aggregation, shared oxidative stress pathways |
| LRRK2 | Parallel mitochondrial dysfunction pathways |
| PINK1 | Shared mitophagy mechanisms |
| PARKIN | Shared mitophagy mechanisms |
| CHCHD10 | Similar protein family, potential functional redundancy |
CHCHD2 interacts with multiple proteins:
| Partner | Interaction Type | Functional Effect |
|---|---|---|
| Mitochondrial complexes | Binding | Oxidative phosphorylation |
| Alpha-synuclein | Protein binding | PD link |
| PINK1 | Pathway | Mitochondrial quality control |
| CHCHD10 | Dimer | Functional redundancy |
| mtDNA proteins | Binding | mtDNA maintenance |
CHCHD2 represents a potential therapeutic target[^chchd2_therapeutic]:
Potential approaches include:
CHCHD2 mutation testing is available:
Potential biomarkers include:
| Protein | Primary Location | Functions |
|---|---|---|
| CHCHD1 | Mitochondria | Unknown |
| CHCHD2 | Mitochondria | OXPHOS, PD |
| CHCHD3 | Mitochondria | Cristae structure |
| CHCHD4 | Mitochondria | Protein import |
| CHCHD5 | Nucleus/Mitochondria | Spermatogenesis |
| CHCHD6 | Mitochondria | Unknown |
| CHCHD10 | Mitochondria | ALS, neuropathy |
CHCHD2 is conserved across species:
| Species | Homolog | Key Features |
|---|---|---|
| Human | CHCHD2 | Reference |
| Mouse | Chchd2 | 90% identical |
| Zebrafish | chchd2 | 85% identical |
| C. elegans | T08B1.2 | 70% identical |
| D. melanogaster | CG31775 | 65% identical |