QPRT | ENSG00000103485 | NCBI 23475

Details for: QPRT

Gene ID: 23475

Gene Type: Protein-coding - A gene that serves as a template for producing a messenger RNA (mRNA) molecule, which is then translated into a functional protein.

Symbol: QPRT

Ensembl ID: ENSG00000103485

Description: quinolinate phosphoribosyltransferase

Cell Significance Landscape

Display Count:

Associated with

Metabolism
(R-HSA-1430728)
Metabolism of vitamins and cofactors
(R-HSA-196854)
Metabolism of water-soluble vitamins and cofactors
(R-HSA-196849)
Nicotinate metabolism
(R-HSA-196807)
Catalytic complex
(GO:1902494)
Cytoplasm
(GO:0005737)
Cytosol
(GO:0005829)
Extracellular exosome
(GO:0070062)
Identical protein binding
(GO:0042802)
Nad biosynthetic process
(GO:0009435)
Nad metabolic process
(GO:0019674)
Nicotinate-nucleotide diphosphorylase (carboxylating) activity
(GO:0004514)
Protein binding
(GO:0005515)
Quinolinate catabolic process
(GO:0034213)

Significant Cells

Cell Significance Index (CSI) scores for the chosen context(s)

intestinal epithelial cell CL0002563

CSI 31.62

rCSI 33.05%

PRS 86.53
extravillous trophoblast CL0008036

CSI 19.89

rCSI 24.6%

PRS 87.38
secretory cell CL0000151

CSI 16.51

rCSI 17.22%

PRS 87.9
fallopian tube secretory epithelial cell CL4030006

CSI 15.47

rCSI 14.9%

PRS 87.67
pulmonary alveolar type 2 cell CL0002063

CSI 14.95

rCSI 23.19%

PRS 90.3
placental villous trophoblast CL2000060

CSI 11.28

rCSI 17.43%

PRS 87.34
vascular associated smooth muscle cell CL0000359

CSI 9.96

rCSI 32.31%

PRS 87.11
ciliated epithelial cell CL0000067

CSI 9.41

rCSI 8.28%

PRS 80.07
myofibroblast cell CL0000186

CSI 9.15

rCSI 12.68%

PRS 85.57
common myeloid progenitor CL0000049

CSI 8.09

rCSI 6.54%

PRS 90.51
epithelial cell of proximal tubule CL0002306

CSI 7.87

rCSI 19.22%

PRS 81.95
IgA plasma cell CL0000987

CSI 7

rCSI 7.16%

PRS 91.47
glial cell CL0000125

CSI 6.95

rCSI 26.46%

PRS 81.9
syncytiotrophoblast cell CL0000525

CSI 6.74

rCSI 19.41%

PRS 90.93
mesodermal cell CL0000222

CSI 6.65

rCSI 7.99%

PRS 87.71
stem cell CL0000034

CSI 6.56

rCSI 6.32%

PRS 84.49
colon epithelial cell CL0011108

CSI 6.24

rCSI 6.54%

PRS 86.43
common lymphoid progenitor CL0000051

CSI 6.18

rCSI 8.26%

PRS 97.21
retinal ganglion cell CL0000740

CSI 6.09

rCSI 13.46%

PRS 77.68
melanocyte CL0000148

CSI 5.75

rCSI 4.26%

PRS 84.8
enterocyte CL0000584

CSI 5.11

rCSI 8.25%

PRS 86.08
hepatic stellate cell CL0000632

CSI 4.85

rCSI 18.18%

PRS 83.77
glioblast CL0000030

CSI 4.68

rCSI 7.46%

PRS 81.31
paneth cell CL0000510

CSI 4.66

rCSI 6.87%

PRS 94.47
goblet cell CL0000160

CSI 4.65

rCSI 4.39%

PRS 86.75
intestine goblet cell CL0019031

CSI 4.56

rCSI 4.05%

PRS 86.35
pancreatic acinar cell CL0002064

CSI 4.56

rCSI 6.05%

PRS 92.09
midzonal region hepatocyte CL0019028

CSI 4.54

rCSI 10.65%

PRS 86.97
kidney epithelial cell CL0002518

CSI 4.4

rCSI 8.4%

PRS 96.06
astrocyte of the cerebral cortex CL0002605

CSI 4.27

rCSI 9.58%

PRS 75.51
epithelial cell CL0000066

CSI 3.95

rCSI 6.07%

PRS 77.59
hematopoietic precursor cell CL0008001

CSI 3.73

rCSI 3.84%

PRS 95.39
fraction A pre-pro B cell CL0002045

CSI 3.66

rCSI 4.19%

PRS 93.89
myeloid leukocyte CL0000766

CSI 3.64

rCSI 3.36%

PRS 90.03
early lymphoid progenitor CL0000936

CSI 3.5

rCSI 3.07%

PRS 92.36
neural crest cell CL0011012

CSI 3.49

rCSI 2.76%

PRS 81.16
enteroendocrine cell CL0000164

CSI 3.49

rCSI 4.77%

PRS 87.68
transit amplifying cell of colon CL0009011

CSI 3.24

rCSI 3.8%

PRS 89.27
fibroblast of lung CL0002553

CSI 3.23

rCSI 3.01%

PRS 90.01
granulocyte CL0000094

CSI 3.19

rCSI 4.88%

PRS 93.58
granulocyte monocyte progenitor cell CL0000557

CSI 3.12

rCSI 2.7%

PRS 91.27
podocyte CL0000653

CSI 3.1

rCSI 13.76%

PRS 89.4
Kupffer cell CL0000091

CSI 2.8

rCSI 6.4%

PRS 89.81
radial glial cell CL0000681

CSI 2.79

rCSI 3.87%

PRS 87.41
interstitial cell of Cajal CL0002088

CSI 2.76

rCSI 3.51%

PRS 92.74
epithelial cell of lung CL0000082

CSI 2.75

rCSI 2.28%

PRS 89.79
hematopoietic stem cell CL0000037

CSI 2.75

rCSI 1.83%

PRS 90.7
Schwann cell CL0002573

CSI 2.59

rCSI 7.35%

PRS 85.15
acinar cell CL0000622

CSI 2.59

rCSI 3.79%

PRS 94.42
M cell of gut CL0000682

CSI 2.47

rCSI 2.62%

PRS 91.32
enteric smooth muscle cell CL0002504

CSI 2.43

rCSI 3.47%

PRS 89.24
colonocyte CL1000347

CSI 2.43

rCSI 3.48%

PRS 87.38
cerebral cortex endothelial cell CL1001602

CSI 2.3

rCSI 3.97%

PRS 83.09
IgG plasma cell CL0000985

CSI 2.29

rCSI 2.75%

PRS 93.53
hepatocyte CL0000182

CSI 2.26

rCSI 4.04%

PRS 87.81
neuroblast (sensu Vertebrata) CL0000031

CSI 2.21

rCSI 2.83%

PRS 85.47
paneth cell of epithelium of small intestine CL1000343

CSI 2.14

rCSI 6%

PRS 92.4
peripheral nervous system neuron CL2000032

CSI 2.03

rCSI 2.77%

PRS 82.21
CD1c-positive myeloid dendritic cell CL0002399

CSI 1.95

rCSI 2.36%

PRS 93.82
smooth muscle cell CL0000192

CSI 1.93

rCSI 4.61%

PRS 83.72
common dendritic progenitor CL0001029

CSI 1.93

rCSI 2.42%

PRS 94.27
intestinal tuft cell CL0019032

CSI 1.89

rCSI 2.88%

PRS 91.04
periportal region hepatocyte CL0019026

CSI 1.85

rCSI 7.18%

PRS 86.3
megakaryocyte-erythroid progenitor cell CL0000050

CSI 1.77

rCSI 1.6%

PRS 87.82
centrilobular region hepatocyte CL0019029

CSI 1.72

rCSI 4.49%

PRS 85.25
glandular epithelial cell CL0000150

CSI 1.71

rCSI 4.5%

PRS 95.34
Langerhans cell CL0000453

CSI 1.51

rCSI 2.31%

PRS 95.33
mesenchymal cell CL0008019

CSI 1.51

rCSI 3.84%

PRS 83.68
transit amplifying cell of small intestine CL0009012

CSI 1.5

rCSI 6.59%

PRS 92.78
enteroendocrine cell of small intestine CL0009006

CSI 1.45

rCSI 3.18%

PRS 92.4
BEST4+ enteroycte CL4030026

CSI 1.42

rCSI 1.77%

PRS 88.77
parietal epithelial cell CL1000452

CSI 1.42

rCSI 3.8%

PRS 82.89
pluripotent stem cell CL0002248

CSI 1.41

rCSI 42.29%

PRS 94.12
kidney connecting tubule epithelial cell CL1000768

CSI 1.36

rCSI 3.45%

PRS 82.02
cardiac muscle cell CL0000746

CSI 1.36

rCSI 1.95%

PRS 80.8
intestinal crypt stem cell of small intestine CL0009017

CSI 1.36

rCSI 3.67%

PRS 91.31
stromal cell CL0000499

CSI 1.33

rCSI 3.74%

PRS 84.85
transit amplifying cell CL0009010

CSI 1.12

rCSI 1.72%

PRS 92.67
enterocyte of epithelium of large intestine CL0002071

CSI 0.89

rCSI 4.66%

PRS 91.05
stromal cell of ovary CL0002132

CSI 0.87

rCSI 2.39%

PRS 92.5
enterocyte of epithelium of small intestine CL1000334

CSI 0.85

rCSI 13.17%

PRS 92.27
microcirculation associated smooth muscle cell CL0008035

CSI 0.78

rCSI 2.27%

PRS 88.07
pancreatic stellate cell CL0002410

CSI 0.78

rCSI 4.52%

PRS 90.72
intestinal crypt stem cell of colon CL0009043

CSI 0.71

rCSI 5.34%

PRS 93.98
pancreatic epsilon cell CL0005019

CSI 0.69

rCSI 3.19%

PRS 92.96
P/D1 enteroendocrine cell CL0002268

CSI 0.6

rCSI 3.24%

PRS 91.8
mesenchymal stem cell CL0000134

CSI 0.23

rCSI 2.54%

PRS 91.25

Cell ID: Standard Cell Ontology term used for mapping and comparing cells across experiments. Ensures consistency in analyzing cellular functions across tissues.
Fold Change: Represents the ratio of the current Cell Significance Index to the Cell Significance Index Threshold, indicating how much the gene expression has changed compared to a baseline.
Cell Significance Index: Reflects how strongly a gene is expressed in this specific cell.

Network Configuration

Explore relationships of the current gene. Select an Interaction Source: 'ONTOLOGY' for shared pathways (GO/Reactome) or 'STRING' for protein-protein interactions. Further refine by selecting context genes and comparing Cell Significance Index (CSI) scores between baseline and target cell types and their specific contexts.

Context Genes (max 20):

Interaction Source:

Pathway Categories (for ONTOLOGY source):

Baseline Cell Type:

Baseline Cell Context(s): Comma-separated if multiple.

Target Cell Type:

Target Cell Context(s): Comma-separated if multiple.

Legend:

Query Gene
Node Color (Target Cell CSI, relative to current network):
- Very High
- High
- Medium
- Low
- Very Low
- CSI N/A
Node Size: Proportional to Target Cell CSI magnitude
STRING PPI Edge
Shared Pathway Edge (ONTOLOGY)

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Other Information

This section provides additional information about the gene, including a description generated by an AI language model and details about associated proteins.

Description
Proteins

## Summary [QPRT](/details-gene/23475) (quinolinate phosphoribosyltransferase) is a protein-coding gene located on chromosome 16p11.2. It encodes a key enzyme in the *de novo* biosynthesis pathway of nicotinamide adenine dinucleotide (NAD+), a crucial coenzyme for numerous cellular redox reactions and signaling processes. The enzyme catalyzes the conversion of quinolinic acid to nicotinic acid mononucleotide. **Overall**, expression data indicates that [QPRT](/details-gene/23475) shows the highest significance in metabolically active epithelial and secretory tissues, particularly in [intestinal epithelial cell](/details-cell/CL0002563) and various trophoblast populations, suggesting a fundamental role in maintaining cellular energy homeostasis and function in these specialized cell types. ## Cellular Roles and Expression Landscape The expression profile of [QPRT](/details-gene/23475) highlights its importance in cells with high metabolic or secretory demands. The **Overall** context reveals its most significant expression in [intestinal epithelial cell](/details-cell/CL0002563) (CSI: 31.62), which is consistent with the high energy requirements for nutrient absorption and maintenance of the gut barrier. A prominent role in placental biology is also suggested by its high significance in multiple trophoblast lineages, including [extravillous trophoblast](/details-cell/CL0008036) (CSI: 19.89), [placental villous trophoblast](/details-cell/CL2000060) (CSI: 11.28), and [syncytiotrophoblast cell](/details-cell/CL0000525) (CSI: 6.74). This pattern implies that robust NAD+ synthesis is critical for placental development, implantation, and maternal-fetal exchange. Furthermore, [QPRT](/details-gene/23475) is highly significant in various secretory and specialized epithelial cells, such as [secretory cell](/details-cell/CL0000151) (CSI: 16.51), [fallopian tube secretory epithelial cell](/details-cell/CL4030006) (CSI: 15.47), [pulmonary alveolar type 2 cell](/details-cell/CL0002063) (CSI: 14.95), and [epithelial cell of proximal tubule](/details-cell/CL0002306) (CSI: 7.87). This suggests its involvement in energetically demanding processes like surfactant production in the lungs and solute reabsorption in the kidneys. Its significance extends to structural cells like [vascular associated smooth muscle cell](/details-cell/CL0000359) and [myofibroblast cell](/details-cell/CL0000186), indicating a broad role in cellular metabolism across diverse tissue types. ## Pathways and Molecular Function Functionally, [QPRT](/details-gene/23475) is an indispensable enzyme in metabolism. It is a central component of the '[Nad biosynthetic process](/details-pathway/GO:0009435)' and more broadly involved in '[Metabolism of vitamins and cofactors](/details-pathway/R-HSA-196854)', specifically '[Nicotinate metabolism](/details-pathway/R-HSA-196807)'. Its molecular function is defined as '[Nicotinate-nucleotide diphosphorylase (carboxylating) activity](/details-pathway/GO:0004514)' ([Link](https://doi.org/10.1016/s0167-4781(97)00143-7)). The protein is primarily localized to the [cytoplasm](/details-pathway/GO:0005737) and [cytosol](/details-pathway/GO:0005829), where it functions as a catalytic complex. Structural studies reveal it assembles into a hexamer to perform its catalytic activity ([Link](https://doi.org/10.1038/srep19681)). The high demand for NAD+ in the top-expressing cell types, such as intestinal and pulmonary epithelia, directly aligns with the central metabolic role of [QPRT](/details-gene/23475). NAD+ is essential not only for ATP production via oxidative phosphorylation but also as a substrate for sirtuins and PARPs, enzymes involved in DNA repair, stress responses, and cell signaling, which are critical functions in high-turnover barrier tissues. ## Research Directions Based on its function and expression landscape, [QPRT](/details-gene/23475) presents several avenues for further investigation, particularly concerning its role in tissue homeostasis and pathology. **Proposed Hypotheses:** 1. **Role in Gut Inflammation:** Given its top significance in [intestinal epithelial cell](/details-cell/CL0002563), dysregulation of [QPRT](/details-gene/23475) may compromise gut barrier function by depleting NAD+ levels, thereby increasing susceptibility to or exacerbating inflammatory bowel disease (IBD). 2. **Placental Insufficiency:** The high expression in multiple trophoblast subtypes suggests that impaired [QPRT](/details-gene/23475) activity could lead to inadequate NAD+ supply during pregnancy, contributing to placental insufficiency, pre-eclampsia, or fetal growth restriction. 3. **Lung Injury and Repair:** In [pulmonary alveolar type 2 cell](/details-cell/CL0002063), [QPRT](/details-gene/23475) may be a critical factor in the regenerative response following lung injury, as epithelial repair is an energetically demanding process highly dependent on NAD+ availability. **Suggested Experimental Approach:** To test the hypothesis regarding [QPRT](/details-gene/23475)'s role in gut inflammation (Hypothesis 1), one could utilize an *in vitro* model of the intestinal epithelium. CRISPR-Cas9 could be used to knock out [QPRT](/details-gene/23475) in human intestinal epithelial cell lines (e.g., Caco-2) or primary intestinal organoids. The impact of this knockout on cellular NAD+/NADH levels, mitochondrial function, and barrier integrity (measured by transepithelial electrical resistance, TEER) would be assessed. Subsequently, these knockout and control cultures could be challenged with inflammatory stimuli like TNF-alpha or LPS to determine if [QPRT](/details-gene/23475) deficiency sensitizes the epithelial barrier to inflammatory damage. **Therapeutic Potential:** [QPRT](/details-gene/23475) represents a potential therapeutic target for modulating cellular metabolism. In conditions characterized by excessive NAD+ consumption, such as certain cancers or chronic inflammatory states, targeted inhibition of [QPRT](/details-gene/23475) could limit the metabolic plasticity of pathological cells. Conversely, in age-related or degenerative diseases associated with NAD+ decline, enhancing the activity of the *de novo* synthesis pathway, potentially through small-molecule activators of [QPRT](/details-gene/23475), could be a beneficial strategy. However, its broad expression in essential barrier tissues necessitates a highly targeted approach to minimize off-target effects.

Disclaimer: This in-silico analysis is generated by an AI language model and may contain inaccuracies or hallucinations. However, it is cross-referenced with curated gene expression data from major biological sources. Please verify the information before use.

Genular Protein ID: 3825082175

Symbol: NADC_HUMAN

Name: Nicotinate-nucleotide pyrophosphorylase [carboxylating]

UniProtKB Accession Codes:

Q15274 Q53XW7 Q96G22 Q9BSG6

Database IDs:

Citations:

PubMed ID: 9473669

Title: Characterization and functional expression of the cDNA encoding human brain quinolinate phosphoribosyltransferase.

PubMed ID: 9473669

DOI: 10.1016/s0167-4781(97)00143-7

PubMed ID: 15489334

Title: The status, quality, and expansion of the NIH full-length cDNA project: the Mammalian Gene Collection (MGC).

PubMed ID: 15489334

DOI: 10.1101/gr.2596504

PubMed ID: 24275569

Title: An enzyme assisted RP-RPLC approach for in-depth analysis of human liver phosphoproteome.

PubMed ID: 24275569

DOI: 10.1016/j.jprot.2013.11.014

PubMed ID: 17868694

Title: Structural and kinetic characterization of quinolinate phosphoribosyltransferase (hQPRTase) from homo sapiens.

PubMed ID: 17868694

DOI: 10.1016/j.jmb.2007.08.043

PubMed ID: 24038671

Title: The crystal structure of human quinolinic acid phosphoribosyltransferase in complex with its inhibitor phthalic acid.

PubMed ID: 24038671

DOI: 10.1002/prot.24406

PubMed ID: 26805589

Title: Structural Insights into the Quaternary Catalytic Mechanism of Hexameric Human Quinolinate Phosphoribosyltransferase, a Key Enzyme in de novo NAD Biosynthesis.

PubMed ID: 26805589

DOI: 10.1038/srep19681

PubMed ID: 21269460

Title: Initial characterization of the human central proteome.

PubMed ID: 21269460

DOI: 10.1186/1752-0509-5-17

Sequence Information:

Length: 297
Mass: 30846
Checksum: E3199814DB9FA0D5
Sequence:

MDAEGLALLL PPVTLAALVD SWLREDCPGL NYAALVSGAG PSQAALWAKS PGVLAGQPFF 
DAIFTQLNCQ VSWFLPEGSK LVPVARVAEV RGPAHCLLLG ERVALNTLAR CSGIASAAAA 
AVEAARGAGW TGHVAGTRKT TPGFRLVEKY GLLVGGAASH RYDLGGLVMV KDNHVVAAGG 
VEKAVRAARQ AADFTLKVEV ECSSLQEAVQ AAEAGADLVL LDNFKPEELH PTATVLKAQF 
PSVAVEASGG ITLDNLPQFC GPHIDVISMG MLTQAAPALD FSLKLFAKEV APVPKIH

Genular Protein ID: 1173712110

Symbol: V9HWJ5_HUMAN

Name: N/A

UniProtKB Accession Codes:

V9HWJ5

Database IDs:

Citations:

PubMed ID: 24722188

Title: Protein interaction network of alternatively spliced isoforms from brain links genetic risk factors for autism.

PubMed ID: 24722188

Sequence Information:

Length: 297
Mass: 30816
Checksum: B3199814CA8EBD7E
Sequence:

MDAEGLALLL PPVTLAALVD SWLREDCPGL NYAALVSGAG PSQAALWAKS PGVLAGQPFF 
DAIFTQLNCQ VSWFLPEGSK LVPVARVAEV RGPAHCLLLG ERVALNTLAR CSGIASAAAA 
AVEAARGAGW TGHVAGTRKT TPGFRLVEKY GLLVGGAASH RYDLGGLVMV KDNHVVAAGG 
VEKAVRAARQ AADFALKVEV ECSSLQEAVQ AAEAGADLVL LDNFKPEELH PTATVLKAQF 
PSVAVEASGG ITLDNLPQFC GPHIDVISMG MLTQAAPALD FSLKLFAKEV APVPKIH

Genular Protein ID: 3503298935

Symbol: B4DDH4_HUMAN

Name: N/A

UniProtKB Accession Codes:

B4DDH4

Database IDs:

Sequence Information:

Length: 152
Mass: 15902
Checksum: 059A30232FE04139
Sequence:

MGPPSLHSPT PSLGPLGALV LSSQHTSPDS CKSPWTLKAV RAARQAADFA LKVEVECSSL 
QEAVQAAEAG ADLVLLDNFK PEELHPTATV LKAQFPSVAV EASGGITLDN LPQFCGPHID 
VISMGMLTQA APALDFSLKL FAKEVAPVPK IH

Details for: QPRT

Cell Significance Landscape

Associated with

Significant Cells

Network Configuration

Legend:

Other Information

Characterization and functional expression of the cDNA encoding human brain quinolinate phosphoribosyltransferase. PubMed ID: 9473669

The status, quality, and expansion of the NIH full-length cDNA project: the Mammalian Gene Collection (MGC). PubMed ID: 15489334

An enzyme assisted RP-RPLC approach for in-depth analysis of human liver phosphoproteome. PubMed ID: 24275569

Structural and kinetic characterization of quinolinate phosphoribosyltransferase (hQPRTase) from homo sapiens. PubMed ID: 17868694

The crystal structure of human quinolinic acid phosphoribosyltransferase in complex with its inhibitor phthalic acid. PubMed ID: 24038671

Structural Insights into the Quaternary Catalytic Mechanism of Hexameric Human Quinolinate Phosphoribosyltransferase, a Key Enzyme in de novo NAD Biosynthesis. PubMed ID: 26805589

Initial characterization of the human central proteome. PubMed ID: 21269460

Protein interaction network of alternatively spliced isoforms from brain links genetic risk factors for autism. PubMed ID: 24722188

PubMed ID: 9473669

PubMed ID: 15489334

PubMed ID: 24275569

PubMed ID: 17868694

PubMed ID: 24038671

PubMed ID: 26805589

PubMed ID: 21269460

PubMed ID: 24722188