NME1 - NME Nucleoside Diphosphate Kinase 1

NME1

<div class="infobox infobox-gene">
<table>
<tr><th colspan="2" style="background:#e8f4f8; text-align:center; font-size:1.1em;">NME1 - Nucleoside Diphosphate Kinase 1</th></tr>
<tr><td><strong>Gene Symbol</strong></td><td>NME1</td></tr>
<tr><td><strong>Full Name</strong></td><td>NME/Nucleoside Diphosphate Kinase 1</td></tr>
<tr><td><strong>Chromosome</strong></td><td>17q21.33</td></tr>
<tr><td><strong>NCBI Gene ID</strong></td><td>[4830](https://www.ncbi.nlm.nih.gov/gene/4830)</td></tr>
<tr><td><strong>OMIM</strong></td><td>[156010](https://www.omim.org/entry/156010)</td></tr>
<tr><td><strong>Ensembl ID</strong></td><td>ENSG00000214021</td></tr>
<tr><td><strong>UniProt ID</strong></td><td>[P15531](https://www.uniprot.org/uniprot/P15531)</td></tr>
<tr><td><strong>Protein Class</strong></td><td>Nucleoside diphosphate kinase</td></tr>
<tr><td><strong>Associated Diseases</strong></td><td>Neuroblastoma, Various Cancers, AD/PD</td></tr>
</table>
</div>

NME1 — NME Nucleoside Diphosphate Kinase 1

Introduction

NME1

<div class="infobox infobox-gene">
<table>
<tr><th colspan="2" style="background:#e8f4f8; text-align:center; font-size:1.1em;">NME1 - Nucleoside Diphosphate Kinase 1</th></tr>
<tr><td><strong>Gene Symbol</strong></td><td>NME1</td></tr>
<tr><td><strong>Full Name</strong></td><td>NME/Nucleoside Diphosphate Kinase 1</td></tr>
<tr><td><strong>Chromosome</strong></td><td>17q21.33</td></tr>
<tr><td><strong>NCBI Gene ID</strong></td><td>[4830](https://www.ncbi.nlm.nih.gov/gene/4830)</td></tr>
<tr><td><strong>OMIM</strong></td><td>[156010](https://www.omim.org/entry/156010)</td></tr>
<tr><td><strong>Ensembl ID</strong></td><td>ENSG00000214021</td></tr>
<tr><td><strong>UniProt ID</strong></td><td>[P15531](https://www.uniprot.org/uniprot/P15531)</td></tr>
<tr><td><strong>Protein Class</strong></td><td>Nucleoside diphosphate kinase</td></tr>
<tr><td><strong>Associated Diseases</strong></td><td>Neuroblastoma, Various Cancers, AD/PD</td></tr>
</table>
</div>

NME1 — NME Nucleoside Diphosphate Kinase 1

Introduction

NME1 (NME Nucleoside Diphosphate Kinase 1), also known as NDPK1 (Nucleoside Diphosphate Kinase 1), is a ubiquitous enzyme that catalyzes the transfer of phosphate groups between nucleoside diphosphates (NDPs) and nucleoside triphosphates (NTPs). Originally discovered as a metastasis suppressor gene in melanoma and breast cancer[^nme1_nature_1996], NME1 plays crucial roles in maintaining cellular nucleotide pools, mitochondrial function, and has been increasingly studied for its potential roles in neuronal survival and neurodegenerative diseases[^nme1_cancer_2003].

The NME1 protein is highly conserved across species and is one of several NME family members in humans (NME1-NME10). While primarily known for its enzymatic function in nucleotide metabolism, NME1 has been implicated in various cellular processes including DNA repair, gene transcription, and apoptosis[^nme1_cancer_2003].

This comprehensive review examines the structure, function, expression patterns, and disease associations of NME1, with particular emphasis on its potential relevance to Alzheimer's disease, Parkinson's disease, and related neurodegenerative conditions.

Protein Structure and Function

Domain Architecture

The NME1 gene (Gene ID: 4830) is located on chromosome 17q21.33 and encodes a 152-amino acid protein with a molecular weight of approximately 17 kDa. The gene consists of a single exon encoding the complete protein, and is part of the NME family that includes at least nine related genes in humans.

Structural Features:

• N-terminal domain: Contains the phosphate-binding loop (P-loop) motif essential for nucleotide binding
• Active site: His-118 serves as the central histidine residue mediating phosphate transfer
• C-terminal region: Involved in protein-protein interactions and oligomerization
• Nucleotide-binding pocket: Accommodates NDPs and NTPs with relatively broad specificity

Enzymatic Activity

NME1 encodes a 17 kDa protein that functions as a homodecameric enzyme. Each subunit contains the characteristic nucleoside diphosphate kinase active site. The enzyme catalyzes the reaction:

NDP + NTP ⇌ NTP + NDP

This reaction is essential for:

• Maintaining cellular pools of NTPs (ATP, GTP, CTP, UTP)
• Supporting DNA and RNA synthesis
• Enabling kinase signaling pathways that require NTPs as phosphate donors

Protein Kinase Activity

Beyond its NDP kinase activity, NME1 exhibits protein kinase activity[^nme1_kinase], allowing it to phosphorylate specific protein substrates. This activity contributes to its roles in:

• Cell migration
• Gene expression
• Apoptosis regulation

DNA-Binding Properties

NME1 can bind to DNA and possesses DNA endonuclease activity[^nme1_dna_repair]. This function relates to its proposed roles in:

• DNA repair pathways
• Transcriptional regulation
• Chromatin remodeling

Mitochondrial Function

Recent research has revealed that NME1 localizes to mitochondria and controls the mitochondrial nucleoside diphosphate pool[^nme1_mitochondria_2015]. This mitochondrial function is critical for:

• Mitochondrial DNA replication and repair
• Cellular respiration and ATP production
• Mitochondrial membrane potential maintenance

Expression Pattern

NME1 is expressed in most human tissues:

| Tissue Type | Expression Level |
|-------------|-------------------|
| Brain | Moderate-high |
| Liver | High |
| Skeletal muscle | High |
| Heart | Moderate |
| Kidney | Moderate |
| Lung | Moderate |

In the brain, NME1 is expressed in both neurons and glial cells, with higher expression in regions with high metabolic demand. Within the brain, NME1 expression is detected in:

• Cerebral cortex
• Hippocampus (CA1-CA3 regions)
• Cerebellum
• Basal ganglia

• Cytoplasm: Primary location for NDP kinase activity
• Nucleus: DNA-binding and potential repair functions
• Mitochondria: Emerging evidence for mitochondrial functions
• Plasma membrane: Association with signaling complexes

Role in Neurodegeneration

Alzheimer's Disease

While not a primary AD risk gene, NME1 may play modulatory roles in Alzheimer's disease pathogenesis:

• Mitochondrial dysfunction: NME1 deficiency exacerbates mitochondrial dysfunction, a key feature of AD
• Nucleotide pool imbalance: Reduced NTP pools may impair DNA repair mechanisms in neurons
• p53 interactions: NME1 modulates p53-dependent apoptosis pathways that are dysregulated in AD[^nme1_p53]

Parkinson's Disease

In Parkinson's disease, mitochondrial dysfunction is a central pathogenic mechanism[^nme1_mitochondria]:

• Complex I deficiency: Similar to sporadic PD, NME1 loss affects mitochondrial complex I function
• Alpha-synuclein interaction: Though not direct, nucleotide pool alterations may affect alpha-synuclein aggregation propensity
• Neuronal vulnerability: Dopaminergic neurons are particularly sensitive to nucleotide pool alterations

Evidence from Model Systems

Studies in C. elegans have shown that the NME1 homolog plays essential roles in neuronal development and survival. Knockdown models exhibit:

• Enhanced sensitivity to mitochondrial toxins
• Altered neuronal morphology
• Premature aging phenotypes

Disease Associations

Cancer (Primary)

NME1 was originally identified as a metastasis suppressor[^nme1_cancer]:

• Reduced NME1 expression correlates with increased metastasis in melanoma, breast cancer, and hepatocellular carcinoma
• Prognostic marker in several cancer types
• Tumor suppressor activity through nucleotide pool regulation

Neuroblastoma

NME1 is particularly relevant in neuroblastoma (the condition that gave it the name "Nm23"):

• Acts as a metastasis suppressor
• Low NME1 expression correlates with metastatic disease
• Potential therapeutic target

Neurodegenerative Diseases

Emerging evidence suggests NME1 may be involved in[^nme1_neuro]:

• Alzheimer's disease pathogenesis
• Parkinson's disease susceptibility
• Amyotrophic lateral sclerosis (ALS)

Interaction Network

NME1 interacts with multiple proteins:

| Partner | Interaction Type | Functional Effect |
|---------|------------------|-------------------|
| NME2 | Oligomerization | Enhanced activity |
| p53 | Protein binding | Apoptosis regulation |
| KSR | Kinase substrate | MAPK signaling |
| HOX proteins | Protein binding | Transcriptional regulation |
| Actin | Binding | Cytoskeletal function |

Therapeutic Implications

Cancer Therapy

NME1 expression status guides treatment decisions in some cancers. Strategies targeting NME1 include[^nme1_therapy]:

• Gene therapy approaches to restore NME1 expression
• Small molecules that reactivate silenced NME1

Neurodegeneration

For neurodegenerative diseases, therapeutic strategies may include:

• Mitochondrial-targeted interventions to compensate for NME1 loss
• Nucleotide pool restoration therapies
• Antioxidant approaches to address ROS increase

Research Directions

Key open questions include:

Comparative Biology

NME1 is highly conserved across species:

| Species | Homolog | Conservation |
|---------|---------|--------------|
| Human | NME1 | Reference |
| Mouse | Nme1 | 95% identical |
| Zebrafish | nme1 | 85% identical |
| C. elegans | nmk-1 | 75% identical |
| D. melanogaster | Nm23 | 80% identical |

The high conservation underscores essential cellular functions.

External Links

• [NCBI Gene - NME1](https://www.ncbi.nlm.nih.gov/gene/4830) - Gene database entry
• [OMIM - NME1](https://www.omim.org/entry/156010) - Online Mendelian Inheritance in Man
• [UniProt - NME1](https://www.uniprot.org/uniprot/P15531) - Protein sequence data
• [Ensembl - NME1](https://www.ensembl.org/Homo_sapiens/Gene/Summary?g=ENSG00000214021) - Genomic resources
• [PubMed - NME1](https://pubmed.ncbi.nlm.nih.gov/?term=NME1+nucleoside+diphosphate+kinase) - Literature search

See Also

• [NME1 Protein](/proteins/nme1-protein) - Protein page
• [NME2 Gene](/genes/nme2) - Related family member
• [Mitochondrial Dysfunction](/mechanisms/mitochondrial-dysfunction) - Related mechanism
• [Alzheimer's Disease](/diseases/alzheimers-disease) - Related disease
• [Parkinson's Disease](/diseases/parkinsons-disease) - Related disease
• [DNA Repair Mechanisms](/mechanisms/dna-repair) - Related mechanism
• [Apoptosis Pathways](/mechanisms/apoptosis-pathways) - Related mechanism

References

Pathway Diagram

The following diagram shows the key molecular relationships involving NME1 - NME Nucleoside Diphosphate Kinase 1 discovered through SciDEX knowledge graph analysis: