Arachidonate 5-lipoxygenase

Arachidonate 5-lipoxygenase
Identifiers
Symbols ALOX5; 5-LO; 5-LOX; 5LPG; LOG5; MGC163204
External IDs OMIM152390 MGI87999 HomoloGene561 GeneCards: ALOX5 Gene
EC number 1.13.11.34
RNA expression pattern
More reference expression data
Orthologs
Species Human Mouse
Entrez 240 11689
Ensembl ENSG00000012779 ENSMUSG00000025701
UniProt P09917 Q3TB75
RefSeq (mRNA) NM_000698.2 NM_009662.2
RefSeq (protein) NP_000689.1 NP_033792.1
Location (UCSC) Chr 10:
45.19 – 45.26 Mb
Chr 6:
116.36 – 116.41 Mb
PubMed search [1] [2]
arachidonate 5-lipoxygenase
Identifiers
EC number 1.13.11.34
CAS number 80619-02-9
Databases
IntEnz IntEnz view
BRENDA BRENDA entry
ExPASy NiceZyme view
KEGG KEGG entry
MetaCyc metabolic pathway
PRIAM profile
PDB structures RCSB PDB PDBe PDBsum
Gene Ontology AmiGO / EGO

Arachidonate 5-lipoxygenase also known as 5-lipoxygenase or 5-LO is an enzyme that in humans is encoded by the ALOX5 gene.[1] Arachidonate 5-lipoxygenase is a member of the lipoxygenase family of enzymes. It transforms EFAs into leukotrienes and is a current target for pharmaceutical intervention in a number of diseases.

Contents

Substrates and products

EFA substrates and leukotriene products of 5-LO include:

Function

5-LO catalyzes oxidation of AA at the 5-position to yield 5-hydroperoxyeicosatetraenoic acid (5-HPETE). 5-LO then converts 5-HPETE to leukotriene A4.[2]

Two other lipoxygenases, 12-LO and 15-LO, act at the 12- and 15-positions, yielding 12- and 15-HPETE. These pathways lead to the leukotriene 12-hydroxyeicosatetraenoic acid (12-HETE) and to the lipoxins, respectively.[3]

Clinical significance

5-LO is a target for pharmaceutical intervention in CAD.[4] Some people with variant alleles for 5-LO are at elevated risk for CAD.[5] 5-LO is expressed in brain cells and may participate in neuropathologic processes.[6]

Mutations in the promoter region of this gene lead to a diminished response to antileukotriene drugs used in the treatment of asthma and may also be associated with atherosclerosis and several cancers. Alternatively spliced transcript variants have been observed, but their full-length nature has not been determined.[7]

5-LO inhibitors

As leukotrienes are important causes of pathological symptoms in asthma, 5-LO inhibitors were developed as asthma treatments. The only 5-LO inhibitor currently licensed for human use in asthma is Zileuton. Minocycline, although primarily a tetracycline antibiotic, is also a 5-LO inhibitor.[8] It may therefore be used as a DMARD-medication in mild rheumatoid arthritis and other rheumatic conditions.[9]

Activation

5-LO is activated by 5-lipoxygenase activating protein (FLAP).

Interactions

Arachidonate 5-lipoxygenase has been shown to interact with Grb2[10][11] and COTL1.[12]

References

  1. ^ Funk CD, Hoshiko S, Matsumoto T, Rdmark O, Samuelsson B (April 1989). "Characterization of the human 5-lipoxygenase gene". Proc. Natl. Acad. Sci. U.S.A. 86 (8): 2587–91. doi:10.1073/pnas.86.8.2587. PMC 286962. PMID 2565035. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=286962. 
  2. ^ Reaction R01595 and R03058 at KEGG Pathway Database.
  3. ^ Dorlands Medical Dictionary, entries at arachidonate 5-lipoxygenase and following. Retrieved on 2006-02-07.
  4. ^ "5-Lipoxygenase, A New Therapeutic And Diagnostic Target For Heart Disease Management". UCLA Case No. 2001-429 PCT Publication Number: WO 03/035670 A2. Archived from the original on 2006-08-30. http://web.archive.org/web/20060830025600/http://www.research.ucla.edu/tech/ucla01-429.htm. Retrieved 2007-11-18. 
  5. ^ Dwyer JH, Allayee H, Dwyer KM, et al. (2004). "Arachidonate 5-lipoxygenase promoter genotype, dietary arachidonic acid, and atherosclerosis". N. Engl. J. Med. 350 (1): 29–37. doi:10.1056/NEJMoa025079. PMID 14702425. 
  6. ^ Zhang L, Zhang WP, Hu H, et al. (2006). "Expression patterns of 5-lipoxygenase in human brain with traumatic injury and astrocytoma". Neuropathology : official journal of the Japanese Society of Neuropathology 26 (2): 99–106. doi:10.1111/j.1440-1789.2006.00658.x. PMID 16708542. 
  7. ^ "Entrez Gene: ALOX5 arachidonate 5-lipoxygenase". http://www.ncbi.nlm.nih.gov/sites/entrez?Db=gene&Cmd=ShowDetailView&TermToSearch=240. 
  8. ^ can be used as DMARDS. Song Y, Wei EQ, Zhang WP, Zhang L, Liu JR, Chen Z (2004). "Minocycline protects PC12 cells from ischemic-like injury and inhibits 5-lipoxygenase activation". Neuroreport 15 (14): 2181–4. doi:10.1097/00001756-200410050-00007. PMID 15371729. 
  9. ^ arthritis.about.com: Minocin - Minocycline - Dosage - Side Effects - Drug Interactions
  10. ^ VanderNoot, V A; Fitzpatrick F A (Sep. 1995). "Competitive binding assay of src homology domain 3 interactions between 5-lipoxygenase and growth factor receptor binding protein 2". Anal. Biochem. (UNITED STATES) 230 (1): 108–14. doi:10.1006/abio.1995.1444. ISSN 0003-2697. PMID 8585605. 
  11. ^ Lepley, R A; Fitzpatrick F A (Sep. 1994). "5-Lipoxygenase contains a functional Src homology 3-binding motif that interacts with the Src homology 3 domain of Grb2 and cytoskeletal proteins". J. Biol. Chem. (UNITED STATES) 269 (39): 24163–8. ISSN 0021-9258. PMID 7929073. 
  12. ^ Provost, P; Doucet J, Hammarberg T, Gerisch G, Samuelsson B, Radmark O (May. 2001). "5-Lipoxygenase interacts with coactosin-like protein". J. Biol. Chem. (United States) 276 (19): 16520–7. doi:10.1074/jbc.M011205200. ISSN 0021-9258. PMID 11297527. 

Further reading

External links