NAMPT Gene: Structure, Function, and Clinical Significance
A comprehensive overview of the NAMPT gene, its protein product, associated diseases, expression patterns, and mutations.
Gene Information Card
| Symbol | NAMPT |
|---|---|
| Full Name | Nicotinamide phosphoribosyltransferase |
| Gene Type | Protein coding |
| Chromosomal Location | 7q22.3 |
| NCBI Gene ID | 10135 ncbi.nlm.nih.gov/gene/10135 |
| Ensembl ID | ENSG00000105835 |
| UniProt ID | P43490 |
| OMIM ID | 608764 |
| HGNC ID | 30092 |
| Aliases | PBEF, PBEF1, visfatin, 1110035O14Rik |
Description
The NAMPT gene encodes nicotinamide phosphoribosyltransferase, a key enzyme in the salvage pathway of NAD+ biosynthesis. It catalyzes the conversion of nicotinamide to nicotinamide mononucleotide (NMN), which is then converted to NAD+. NAMPT is also known as pre-B-cell colony-enhancing factor (PBEF) and visfatin, reflecting its roles in immune function and adipokine signaling. The protein is localized to the cytoplasm, nucleus, and extracellular space, and is involved in multiple cellular processes including metabolism, inflammation, and cell survival.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Type 2 Diabetes | NAMPT/visfatin modulates insulin sensitivity and glucose metabolism; altered expression is associated with insulin resistance. | Multiple studies show elevated serum visfatin in T2D patients; GWAS links NAMPT variants to metabolic traits. |
| Obesity | NAMPT is upregulated in visceral adipose tissue; contributes to chronic inflammation and metabolic dysregulation. | Expression correlates with BMI and waist circumference; functional studies in adipocytes. |
| Rheumatoid Arthritis | NAMPT acts as a pro-inflammatory cytokine (PBEF) in synovial fibroblasts; promotes inflammation and joint damage. | Elevated levels in synovial fluid and serum; inhibition reduces inflammation in animal models. |
| Colorectal Cancer | NAMPT overexpression supports tumor cell proliferation and survival via NAD+ production; potential therapeutic target. | Immunohistochemistry shows high expression in tumors; NAMPT inhibitors reduce tumor growth in xenografts. |
| Acute Myeloid Leukemia | NAMPT is overexpressed in leukemic blasts; inhibition induces apoptosis and differentiation. | Preclinical studies with NAMPT inhibitors (e.g., FK866) show efficacy; clinical trials ongoing. |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Bone Marrow | 11.2 | Medium |
| Adipose Tissue | 9.8 | Medium |
| Liver | 8.5 | Medium |
| Muscle | 6.3 | Low |
| Brain | 5.1 | Low |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| HeLa | 12.5 | High expression; used in NAD metabolism studies. |
| HepG2 | 10.2 | Moderate; liver cancer cell line. |
| MCF7 | 8.9 | Breast cancer; NAMPT expression linked to proliferation. |
| THP-1 | 15.3 | Monocytic leukemia; high expression due to inflammatory role. |
| A549 | 7.4 | Lung carcinoma; moderate expression. |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| rs2302559 (G/A) | SNP (intronic) | Minor allele frequency ~0.2 | Associated with altered NAMPT expression and metabolic traits; no direct functional effect known. |
| rs1319501 (C/T) | SNP (intronic) | MAF ~0.3 | Linked to inflammatory diseases; may affect splicing. |
| c.473C>T (p.Thr158Ile) | Missense | Rare (<0.01) | Potential impact on enzyme activity; reported in cancer samples. |
| c.1100A>G (p.Gln367Arg) | Missense | Rare | Found in COSMIC; functional significance unknown. |
Mutation functional classification
Loss of Function (LOF)
Loss-of-function mutations in NAMPT are rare and often lethal in homozygous state; heterozygous mutations may reduce enzyme activity, leading to impaired NAD+ biosynthesis and cellular energy deficits.
Gain of Function (GOF)
Gain-of-function mutations are not well documented; overexpression of wild-type NAMPT is more common in cancer and metabolic diseases, promoting cell survival and inflammation.
Dominant Negative (DN)
No dominant-negative mutations have been reported for NAMPT; however, some missense variants may interfere with dimerization, potentially exerting a dominant-negative effect.
View complete mutation data：
Gene Ontology (GO)
Pathways
• Nicotinate and nicotinamide metabolism (KEGG: hsa00760)
• NAD+ salvage pathway
• Sirtuin signaling pathway
• Inflammatory response pathway (NF-kB signaling)
Protein Summary
NAMPT is a 52 kDa protein that exists as a dimer and catalyzes the rate-limiting step in the NAD+ salvage pathway. It has both intracellular and extracellular functions. Intracellularly, it regulates NAD+ levels, influencing sirtuin activity and cellular metabolism. Extracellularly, it acts as a cytokine (visfatin/PBEF) involved in inflammation and immune responses. The protein is widely expressed, with highest levels in bone marrow and adipose tissue. Its dysregulation is implicated in metabolic disorders, inflammatory diseases, and cancer, making it a promising therapeutic target.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| NAMPT Knockout Jurkat Cell Line | EDJ-KQ78105 | Human | 10135 | Details Get a Quote |
| NAMPT Knockout HEK293T Cell Line | EDJ-KQ78131 | Human | 10135 | Details Get a Quote |
| NAMPT Knockout HCT 116 Cell Line | EDJ-KQ78132 | Human | 10135 | Details Get a Quote |
Displaying Records 1 To 3 Of 3 Records
