PON1

Last updated
PON1
PDB 1v04 EBI.jpg
Available structures
PDB Ortholog search: PDBe RCSB
Identifiers
Aliases PON1 , ESA, MVCD5, PON, paraoxonase 1
External IDs OMIM: 168820 MGI: 103295 HomoloGene: 68058 GeneCards: PON1
Orthologs
SpeciesHumanMouse
Entrez
Ensembl
UniProt
RefSeq (mRNA)

NM_000446

NM_011134

RefSeq (protein)

NP_000437

NP_035264

Location (UCSC) Chr 7: 95.3 – 95.32 Mb Chr 6: 5.17 – 5.19 Mb
PubMed search [3] [4]
Wikidata
View/Edit Human View/Edit Mouse

Paraoxonase 1 (PON1) also known as Serum paraoxonase and arylesterase 1, A esterase, homocysteine thiolactonase or serum aryldialkylphosphatase 1, is an enzyme that in humans is encoded by the PON1 gene. [5] Paraoxonase 1 has esterase and more specifically paraoxonase activity. [6] PON1 is the first discovered member of a multigene family also containing PON2 and PON3, the genes for which are located adjacent to each other on chromosome 7. PON1 on HDL (different from soluble PON1) is responsible for significant atheroprotection rendered by the HDL. [7]

Contents

Structure

Human PON1 is a glycoprotein composed of 354 amino acids and has a molecular weight of 43,000 daltons which associates with high-density lipoprotein (HDL, cholesterol) in the circulation. Serum PON1 is secreted mainly by the liver, although local synthesis occurs in several tissues and PON1 protein is found in almost all tissues. X-ray crystallography has revealed the structure of PON1 to be a 6 bladed propeller with a unique lid structure covering the active site passage which allows association with HDL. [8] [9] [10]

Function

PON1 is responsible for hydrolysing organophosphate pesticides and nerve gasses. Polymorphisms in the PON1 gene significantly affect the catalytic ability of the enzyme. [11]

PON1 (paraoxonase 1) is also a major anti-atherosclerotic component of high-density lipoprotein (HDL). [12] [13] The PON1 gene is activated by PPAR-γ, which increases synthesis and release of paraoxonase 1 enzyme from the liver, reducing atherosclerosis. [14]

PON1 is a highly promiscuous enzyme capable of hydrolysing a wide variety of substrates, such as lactones, [15] including thiolactones and pharmaceutical agents such as statins. PON1 substrates also include glucuronide drugs, arylesters, cyclic carbonates, organophosphorus pesticides and nerve gases such as sarin, soman and VX, oestrogen esters and lipid peroxides (oxidized lipids). Oxidized polyunsaturated fatty acids (notably in oxidized low-density lipoprotein) form lactone-like structures that are PON substrates. [16]

Genetics

PON1 in humans is encoded by the PON1 gene, which is located on the long arm of chromosome 7. [17] PON1 activity can vary by over 40 fold between individuals. The biggest effect on PON1 activity levels is through PON1 genetic polymorphisms. [9] Many nutritional, life-style and pharmaceutical modulators of PON1 are also known. [18] [19]

The coding region PON1-Q192R polymorphism determines a substrate dependent effect on activity. Many organophosphates used in pesticides, such as paraoxon, are hydrolysed faster by the PON1-R allozyme. Other substrates such as diazoxon, lipid-peroxides and sarin are hydrolysed more rapidly by the PON1-Q allozyme. [9]

Both the coding region PON1-L55M and the promoter region PON1-T-108C polymorphisms are associated with different serum concentrations and therefore activities. The 55L allele results in significantly higher PON1 mRNA and serum protein levels and therefore activity compared to the 55M allele. [18] [19] The -108C allele has greater promoter activity than the -108T allele which results in different serum activities. [18] [19]

The distribution of the PON1 polymorphisms varies with ethnicity. The frequency of the PON1-192R allele increases the further from Europe a population originates, the frequency in Caucasians of 15-30% increases to 70-90% in Far Eastern Oriental and Sub-Saharan African populations. [20] In the southern US, African-Americans are five times more likely to be RR than Caucasians. [21] In contrast, the PON1-55M allele is much less frequent in Oriental and black African populations compared to Caucasians and are extremely rare or absent in some populations e.g. Thais. These ethnic differences in SNP distribution can lead to large activity differences between populations. [20]

Clinical significance

PON1 was first discovered through its ability to hydrolyse and therefore detoxify organophosphorus compounds which are widely used as pesticides and nerve gases. PON1 protects humans from the acute and chronic harmful effects of these compounds. [22] [23] Low PON1 activity found in children may increase their susceptibility to organophosphates. Because PON1-Q is more protective against sarin than PON1-R, the PON1-R allele and low PON1-Q activity levels are associated with Gulf War Illness. [24]

The greatest research interest has been the role of PON1 in atherosclerosis, where, because of its ability to remove harmful oxidised-lipids, PON1 protects against the development of atherosclerosis. [25]

PON1 also protects against bacterial infection by destroying the bacterial signalling molecules that cause gram negative bacteria to invade human tissue and form colonies, thus PON1 contributes to the bodies innate immunity. [26]

Recently it has been suggested that PON1 has a role in healthy aging, however, the mechanism is currently unknown. [27]

PON1 activity is low in infants compared to adults. A study of Mexican-American children showed that PON1 activity increased 3.5 times between birth and age seven. [28]

An association between PON1 gene polymorphism and susceptibility to Parkinson's disease was not found in a Chinese population. [29]

Notes

Related Research Articles

<span class="mw-page-title-main">Methylenetetrahydrofolate reductase</span> Rate-limiting enzyme in the methyl cycle

Methylenetetrahydrofolate reductase (MTHFR) is the rate-limiting enzyme in the methyl cycle, and it is encoded by the MTHFR gene. Methylenetetrahydrofolate reductase catalyzes the conversion of 5,10-methylenetetrahydrofolate to 5-methyltetrahydrofolate, a cosubstrate for homocysteine remethylation to methionine. Natural variation in this gene is common in otherwise healthy people. Although some variants have been reported to influence susceptibility to occlusive vascular disease, neural tube defects, Alzheimer's disease and other forms of dementia, colon cancer, and acute leukemia, findings from small early studies have not been reproduced. Some mutations in this gene are associated with methylenetetrahydrofolate reductase deficiency. Complex I deficiency with recessive spastic paraparesis has also been linked to MTHFR variants. In addition, the aberrant promoter hypermethylation of this gene is associated with male infertility and recurrent spontaneous abortion.

<span class="mw-page-title-main">Cholesteryl ester transfer protein</span> Mammalian protein found in Homo sapiens

Cholesteryl ester transfer protein (CETP), also called plasma lipid transfer protein, is a plasma protein that facilitates the transport of cholesteryl esters and triglycerides between the lipoproteins. It collects triglycerides from very-low-density (VLDL) or Chylomicrons and exchanges them for cholesteryl esters from high-density lipoproteins (HDL), and vice versa. Most of the time, however, CETP does a heteroexchange, trading a triglyceride for a cholesteryl ester or a cholesteryl ester for a triglyceride.

<span class="mw-page-title-main">CYP2C19</span> Mammalian protein found in humans

Cytochrome P450 2C19 is an enzyme protein. It is a member of the CYP2C subfamily of the cytochrome P450 mixed-function oxidase system. This subfamily includes enzymes that catalyze metabolism of xenobiotics, including some proton pump inhibitors and antiepileptic drugs. In humans, it is the CYP2C19 gene that encodes the CYP2C19 protein. CYP2C19 is a liver enzyme that acts on at least 10% of drugs in current clinical use, most notably the antiplatelet treatment clopidogrel (Plavix), drugs that treat pain associated with ulcers, such as omeprazole, antiseizure drugs such as mephenytoin, the antimalarial proguanil, and the anxiolytic diazepam.

<span class="mw-page-title-main">UDP glucuronosyltransferase 1 family, polypeptide A1</span> Enzyme found in humans

UDP-glucuronosyltransferase 1-1 also known as UGT-1A is an enzyme that in humans is encoded by the UGT1A1 gene.

<span class="mw-page-title-main">Mannan-binding lectin</span> Mammalian protein found in Homo sapiens

Mannose-binding lectin (MBL), also called mannan-binding lectin or mannan-binding protein (MBP), is a lectin that is instrumental in innate immunity as an opsonin and via the lectin pathway.

<span class="mw-page-title-main">Prostacyclin synthase</span> Enzyme found in humans

Prostaglandin-I synthase also known as prostaglandin I2 (prostacyclin) synthase (PTGIS) or CYP8A1 is an enzyme involved in prostanoid biosynthesis that in humans is encoded by the PTGIS gene. This enzyme belongs to the family of cytochrome P450 isomerases.

<span class="mw-page-title-main">Mevalonate kinase</span> Mammalian protein found in Homo sapiens

Mevalonate kinase is an enzyme that in humans is encoded by the MVK gene. Mevalonate kinases are found in a wide variety of organisms from bacteria to mammals. This enzyme catalyzes the following reaction:

<span class="mw-page-title-main">Butyrylcholinesterase</span> Mammalian protein found in humans

Butyrylcholinesterase, also known asBChE, BuChE, BuChase, pseudocholinesterase, or plasma (cholin)esterase, is a nonspecific cholinesterase enzyme that hydrolyses many different choline-based esters. In humans, it is made in the liver, found mainly in blood plasma, and encoded by the BCHE gene.

<span class="mw-page-title-main">Organophosphate poisoning</span> Toxic effect of pesticides

Organophosphate poisoning is poisoning due to organophosphates (OPs). Organophosphates are used as insecticides, medications, and nerve agents. Symptoms include increased saliva and tear production, diarrhea, vomiting, small pupils, sweating, muscle tremors, and confusion. While onset of symptoms is often within minutes to hours, some symptoms can take weeks to appear. Symptoms can last for days to weeks.

<span class="mw-page-title-main">Endothelial NOS</span> Protein and coding gene in humans

Endothelial NOS (eNOS), also known as nitric oxide synthase 3 (NOS3) or constitutive NOS (cNOS), is an enzyme that in humans is encoded by the NOS3 gene located in the 7q35-7q36 region of chromosome 7. This enzyme is one of three isoforms that synthesize nitric oxide (NO), a small gaseous and lipophilic molecule that participates in several biological processes. The other isoforms include neuronal nitric oxide synthase (nNOS), which is constitutively expressed in specific neurons of the brain and inducible nitric oxide synthase (iNOS), whose expression is typically induced in inflammatory diseases. eNOS is primarily responsible for the generation of NO in the vascular endothelium, a monolayer of flat cells lining the interior surface of blood vessels, at the interface between circulating blood in the lumen and the remainder of the vessel wall. NO produced by eNOS in the vascular endothelium plays crucial roles in regulating vascular tone, cellular proliferation, leukocyte adhesion, and platelet aggregation. Therefore, a functional eNOS is essential for a healthy cardiovascular system.

<span class="mw-page-title-main">MMP3</span>

Stromelysin-1 also known as matrix metalloproteinase-3 (MMP-3) is an enzyme that in humans is encoded by the MMP3 gene. The MMP3 gene is part of a cluster of MMP genes which localize to chromosome 11q22.3. MMP-3 has an estimated molecular weight of 54 kDa.

<span class="mw-page-title-main">APOA5</span> Protein-coding gene in the species Homo sapiens

Apolipoprotein A-V is a protein that in humans is encoded by the APOA5 gene on chromosome 11. It is significantly expressed in liver. The protein encoded by this gene is an apolipoprotein and an important determinant of plasma triglyceride levels, a major risk factor for coronary artery disease. It is a component of several lipoprotein fractions including VLDL, HDL, chylomicrons. It is believed that apoA-V affects lipoprotein metabolism by interacting with LDL-R gene family receptors. Considering its association with lipoprotein levels, APOA5 is implicated in metabolic syndrome. The APOA5 gene also contains one of 27 SNPs associated with increased risk of coronary artery disease.

<span class="mw-page-title-main">FADS2</span> Protein-coding gene in the species Homo sapiens

Fatty acid desaturase 2 (FADS2) is an enzyme that in humans is encoded by the FADS2 gene.

<span class="mw-page-title-main">Aryldialkylphosphatase</span>

Aryldialkylphosphatase is a metalloenzyme that hydrolyzes the triester linkage found in organophosphate insecticides:

The enzyme arylesterase (EC 3.1.1.2) catalyzes the reaction

<span class="mw-page-title-main">PON2</span> Protein-coding gene in the species Homo sapiens

Serum paraoxonase/arylesterase 2 is an enzyme that in humans is encoded by the PON2 gene.

<span class="mw-page-title-main">PON3</span> Protein-coding gene in the species Homo sapiens

Paraoxonase 3, also known as PON3, is a protein which in humans is encoded by the PON3 gene.

<span class="mw-page-title-main">Paraoxonase</span> Class of enzymes

Paraoxonases are a family of mammalian enzymes with aryldialkylphosphatase activity. There are three paraoxonase isozymes, which were originally discovered for their involvement in the hydrolysis of organophosphates.

<span class="mw-page-title-main">GPX3</span> Enzyme in humans

Glutathione peroxidase 3 (GPx-3), also known as plasma glutathione peroxidase (GPx-P) or extracellular glutathione peroxidase is an enzyme that in humans is encoded by the GPX3 gene.

<span class="mw-page-title-main">Gene polymorphism</span> Occurrence in an interbreeding population of two or more discontinuous genotypes

A gene is said to be polymorphic if more than one allele occupies that gene's locus within a population. In addition to having more than one allele at a specific locus, each allele must also occur in the population at a rate of at least 1% to generally be considered polymorphic.

References

  1. 1 2 3 GRCh38: Ensembl release 89: ENSG00000005421 Ensembl, May 2017
  2. 1 2 3 GRCm38: Ensembl release 89: ENSMUSG00000002588 Ensembl, May 2017
  3. "Human PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
  4. "Mouse PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
  5. Primo-Parmo SL, Sorenson RC, Teiber J, La Du BN (May 1996). "The human serum paraoxonase/arylesterase gene (PON1) is one member of a multigene family". Genomics. 33 (3): 498–507. doi:10.1006/geno.1996.0225. PMID   8661009.
  6. van Himbergen TM, van Tits LJ, Roest M, Stalenhoef AF (Feb 2006). "The story of PON1: how an organophosphate-hydrolysing enzyme is becoming a player in cardiovascular medicine". The Netherlands Journal of Medicine. 64 (2): 34–8. PMID   16517986.
  7. Kumar S, Maniya N, Wang C, Satyajyoti S, Chang HC (Feb 2023). "Quantifying PON1 on HDL with nanoparticle-gated electrokinetic membrane sensor for accurate cardiovascular risk assessment". Nature Communications. 14 (557): 557. Bibcode:2023NatCo..14..557K. doi:10.1038/s41467-023-36258-w. PMC   9895453 . PMID   36732521.
  8. Harel M, Aharoni A, Gaidukov L, Brumshtein B, Khersonsky O, Meged R, et al. (May 2004). "Structure and evolution of the serum paraoxonase family of detoxifying and anti-atherosclerotic enzymes". Nature Structural & Molecular Biology. 11 (5): 412–9. doi:10.1038/nsmb767. PMID   15098021. S2CID   52874893.
  9. 1 2 3 Mackness B, Durrington PN, Mackness MI (Sep 1998). "Human serum paraoxonase". General Pharmacology. 31 (3): 329–36. doi:10.1016/s0306-3623(98)00028-7. PMID   9703197.
  10. Deakin SP, James RW (Nov 2004). "Genetic and environmental factors modulating serum concentrations and activities of the antioxidant enzyme paraoxonase-1". Clinical Science. 107 (5): 435–47. doi:10.1042/CS20040187. PMID   15265000. S2CID   18754293.
  11. Costa LG, Cole TB, Vitalone A, Furlong CE (Feb 2005). "Measurement of paraoxonase (PON1) status as a potential biomarker of susceptibility to organophosphate toxicity". Clinica Chimica Acta; International Journal of Clinical Chemistry. 352 (1–2): 37–47. doi:10.1016/j.cccn.2004.09.019. PMID   15653099.
  12. Getz GS, Reardon CA (Jun 2004). "Paraoxonase, a cardioprotective enzyme: continuing issues". Current Opinion in Lipidology. 15 (3): 261–7. doi:10.1097/00041433-200406000-00005. PMID   15166781. S2CID   23497678.
  13. Mackness M, Mackness B (Nov 2004). "Paraoxonase 1 and atherosclerosis: is the gene or the protein more important?". Free Radical Biology & Medicine. 37 (9): 1317–23. doi:10.1016/j.freeradbiomed.2004.07.034. PMID   15454272.
  14. Khateeb J, Gantman A, Kreitenberg AJ, Aviram M, Fuhrman B (Jan 2010). "Paraoxonase 1 (PON1) expression in hepatocytes is upregulated by pomegranate polyphenols: a role for PPAR-gamma pathway". Atherosclerosis. 208 (1): 119–25. doi:10.1016/j.atherosclerosis.2009.08.051. PMID   19783251.
  15. Khersonsky O, Tawfik DS (Apr 2005). "Structure-reactivity studies of serum paraoxonase PON1 suggest that its native activity is lactonase". Biochemistry. 44 (16): 6371–82. doi:10.1021/bi047440d. PMID   15835926.
  16. Chistiakov DA, Melnichenko AA, Orekhov AN, Bobryshev YV (2017). "Paraoxonase and atherosclerosis-related cardiovascular diseases". Biochimie . 132: 19–27. doi:10.1016/j.biochi.2016.10.010. PMID   27771368.
  17. Clendenning JB, Humbert R, Green ED, Wood C, Traver D, Furlong CE (Aug 1996). "Structural organization of the human PON1 gene". Genomics. 35 (3): 586–9. doi:10.1006/geno.1996.0401. PMID   8812495.
  18. 1 2 3 Costa LG, Vitalone A, Cole TB, Furlong CE (Feb 2005). "Modulation of paraoxonase (PON1) activity". Biochemical Pharmacology. 69 (4): 541–50. doi:10.1016/j.bcp.2004.08.027. PMID   15670573.
  19. 1 2 3 Schrader C, Graeser AC, Huebbe P, Wagner AE, Rimbach G (Feb 2012). "Allyl isothiocyanate as a potential inducer of paraoxonase-1--studies in cultured hepatocytes and in mice". IUBMB Life. 64 (2): 162–8. doi: 10.1002/iub.587 . PMID   22131196. S2CID   26735383.
  20. 1 2 La Du BN (1992). "Human serum paraoxonase/arylesterase". In Kalow W (ed.). Pharmacogenetics of Drug Metabolism. New York: Pergamon Press. pp. 51–91.
  21. McDaniel CY, Dail MB, Wills RW, Chambers HW, Chambers JE (Dec 2014). "Paraoxonase 1 polymorphisms within a Mississippi USA population as possible biomarkers of enzyme activities associated with disease susceptibility". Biochemical Genetics. 52 (11–12): 509–23. doi:10.1007/s10528-014-9663-8. PMID   25027835. S2CID   16649798.
  22. Costa LG, Giordano G, Cole TB, Marsillach J, Furlong CE (May 2013). "Paraoxonase 1 (PON1) as a genetic determinant of susceptibility to organophosphate toxicity". Toxicology. 307: 115–122. doi:10.1016/j.tox.2012.07.011. PMC   3516631 . PMID   22884923.
  23. Mackness M, Mackness B (2014). "Current aspects of paraoxonase-1 research". In Komoda T (ed.). The HDL handbook : biological functions and clinical implications (Second ed.). Amsterdam: Academic Press. ISBN   978-0-12-407867-3.
  24. Haley RW, Kramer G, Xiao J, Dever JA, Teiber JF (May 2022). "Evaluation of a Gene-Environment Interaction of PON1 and Low-Level Nerve Agent Exposure with Gulf War Illness: A Prevalence Case-Control Study Drawn from the U.S. Military Health Survey's National Population Sample". Environmental Health Perspectives. 130 (5): 57001. doi:10.1289/EHP9009. PMC   9093163 . PMID   35543525.
  25. Costa LG, Cole TB, Jarvik GP, Furlong CE (2003). "Functional genomic of the paraoxonase (PON1) polymorphisms: effects on pesticide sensitivity, cardiovascular disease, and drug metabolism". Annual Review of Medicine. 54: 371–92. doi:10.1146/annurev.med.54.101601.152421. PMID   12525679.
  26. Camps J, Pujol I, Ballester F, Joven J, Simó JM (Apr 2011). "Paraoxonases as potential antibiofilm agents: their relationship with quorum-sensing signals in Gram-negative bacteria". Antimicrobial Agents and Chemotherapy. 55 (4): 1325–31. doi:10.1128/AAC.01502-10. PMC   3067127 . PMID   21199929.
  27. Lee YS, Park CO, Noh JY, Jin S, Lee NR, Noh S, et al. (Sep 2012). "Knockdown of paraoxonase 1 expression influences the ageing of human dermal microvascular endothelial cells". Experimental Dermatology. 21 (9): 682–7. doi:10.1111/j.1600-0625.2012.01555.x. PMID   22897574. S2CID   12440057.
  28. Huen K, Harley K, Bradman A, Eskenazi B, Holland N (Apr 2010). "Longitudinal changes in PON1 enzymatic activities in Mexican-American mothers and children with different genotypes and haplotypes". Toxicology and Applied Pharmacology. 244 (2): 181–9. doi:10.1016/j.taap.2009.12.031. PMC   2846980 . PMID   20045427.
  29. Wang J, Liu Z (Nov 2000). "No association between paraoxonase 1 (PON1) gene polymorphisms and susceptibility to Parkinson's disease in a Chinese population". Movement Disorders. 15 (6): 1265–7. doi:10.1002/1531-8257(200011)15:6<1265::AID-MDS1034>3.0.CO;2-0. PMID   11104219. S2CID   35775326.

Further reading