Polyunsaturated fatty acid lipoxygenase ALOX12
Also known as: 12LO, ALOX12, LOG12
Function
Catalyzes the regio and stereo-specific incorporation of molecular oxygen into free and esterified polyunsaturated fatty acids generating lipid hydroperoxides that can be further reduced to the corresponding hydroxy species. Mainly converts arachidonate ((5Z,8Z,11Z,14Z)-eicosatetraenoate) to the specific bioactive lipid (12S)-hydroperoxyeicosatetraenoate/(12S)-HPETE. Through the production of bioactive lipids like (12S)-HPETE it regulates different biological processes including platelet activation. It can also catalyze the epoxidation of double bonds of polyunsaturated fatty acids such as (14S)-hydroperoxy-docosahexaenoate/(14S)-HPDHA resulting in the formation of (13S,14S)-epoxy-DHA. Furthermore, it may participate in the sequential oxidations of DHA ((4Z,7Z,10Z,13Z,16Z,19Z)-docosahexaenoate) to generate specialized pro-resolving mediators (SPMs) like resolvin D5 ((7S,17S)-diHPDHA) and (7S,14S)-diHPDHA, that actively down-regulate the immune response and have anti-aggregation properties with platelets. An additional function involves a multistep process by which it transforms leukotriene A4/LTA4 into the bioactive lipids lipoxin A4/LXA4 and lipoxin B4/LXB4, both are vasoactive and LXA4 may regulate neutrophil function via occupancy of specific recognition sites. Can also peroxidize linoleate ((9Z,12Z)-octadecadienoate) to (13S)-hydroperoxyoctadecadienoate/ (13S-HPODE) (By similarity). Due to its role in regulating both the expression of the vascular endothelial growth factor (VEGF, an angiogenic factor involved in the survival and metastasis of solid tumors) and the expression of integrin beta-1 (known to affect tumor cell migration and proliferation), it can be regarded as protumorigenic. Important for cell survival, as it may play a role not only in proliferation but also in the prevention of apoptosis in vascular smooth muscle cells.
Classification
- Family (Pfam)
- PF00305 Lipoxygenase, PF01477 PLAT
- InterPro
- LipOase, LipOase_C, LipOase_C_sf, LipOase_CS, LipOase_Fe_BS, LipOase_mml, PLAT/LH2_dom, PLAT/LH2_dom_sf, PLAT_LOX_verte
- Functional cluster
- Membrane Channels & Lipid-Anchored Proteins
Experimental structures · PDB · 5
A predicted model is available from AlphaFold.
Gene Ontology · 25
- GO:0005737 cytoplasm
- GO:0005829 cytosol
- GO:0070062 extracellular exosome
- GO:0016020 membrane
- GO:0042383 sarcolemma
- GO:0004052 arachidonate 12(S)-lipoxygenase activity
- GO:0050473 arachidonate 15-lipoxygenase activity
- GO:0047977 hepoxilin-epoxide hydrolase activity
- GO:0005506 iron ion binding
- GO:0016165 linoleate 13S-lipoxygenase activity
- GO:0019369 arachidonate metabolic process
- GO:0061436 establishment of skin barrier
- GO:0019395 fatty acid oxidation
- GO:0051122 hepoxilin biosynthetic process
- GO:1901751 leukotriene A4 metabolic process
- GO:0043651 linoleic acid metabolic process
- GO:0006629 lipid metabolic process
- GO:0034440 lipid oxidation
- GO:2001303 lipoxin A4 biosynthetic process
- GO:2001306 lipoxin B4 biosynthetic process
- GO:0019372 lipoxygenase pathway
- GO:0010656 negative regulation of muscle cell apoptotic process
- GO:0090331 negative regulation of platelet aggregation
- GO:0042554 superoxide anion generation
- GO:0033559 unsaturated fatty acid metabolic process
Disease associations
- colorectal cancer MONDO:0005575
- esophageal cancer MONDO:0007576
Drugs targeting this protein · 1
- BENOXAPROFEN inhibitor
Related proteins · sequence + function similarity
- Polyunsaturated fatty acid lipoxygenase ALOX12 0.99
- Polyunsaturated fatty acid lipoxygenase ALOX12 0.99
- Polyunsaturated fatty acid lipoxygenase ALOX15 0.98
- Polyunsaturated fatty acid lipoxygenase ALOX15 0.98
- Polyunsaturated fatty acid lipoxygenase ALOX15 0.98
- Polyunsaturated fatty acid lipoxygenase ALOX15 0.98
- Polyunsaturated fatty acid lipoxygenase ALOX15 0.97
- Polyunsaturated fatty acid (12S)/(13S)-lipoxygenase, epidermal-type 0.97
- Polyunsaturated fatty acid (12S)/(13S)-lipoxygenase, epidermal-type 0.96
- Polyunsaturated fatty acid lipoxygenase ALOX15 0.94
- Polyunsaturated fatty acid lipoxygenase ALOX15 0.94
- Hydroperoxide isomerase ALOXE3 0.94
Co-cited proteins · studied together in the literature
- Polyunsaturated fatty acid lipoxygenase ALOX15B 5 shared papers
- Polyunsaturated fatty acid lipoxygenase ALOX15 3 shared papers
- Polyunsaturated fatty acid lipoxygenase ALOX15 2 shared papers
- Polyunsaturated fatty acid lipoxygenase ALOX15 2 shared papers
- Polyunsaturated fatty acid 5-lipoxygenase 3 shared papers
- Prostaglandin G/H synthase 1 1 shared papers
- Prostaglandin G/H synthase 2 1 shared papers
Literature · 28 cited papers
- 15-Lipoxygenase-1 biosynthesis of 7S,14S-diHDHA implicates 15-lipoxygenase-2 in biosynthesis of resolvin D5. J. Lipid Res. · 2020
- Maresin biosynthesis and identification of maresin 2, a new anti-inflammatory and pro-resolving mediator from human macrophages. PLoS ONE · 2014
- Functional characterization of genetic enzyme variations in human lipoxygenases. Redox Biol. · 2013
- 12S-Lipoxygenase is necessary for human vascular smooth muscle cell survival. Exp. Cell Res. · 2013
- The novel 13S,14S-epoxy-maresin is converted by human macrophages to maresin 1 (MaR1), inhibits leukotriene A4 hydrolase (LTA4H), and shifts macrophage phenotype. FASEB J. · 2013
- Investigations of human platelet-type 12-lipoxygenase: role of lipoxygenase products in platelet activation. J. Lipid Res. · 2012
- Up-regulation of 12(S)-lipoxygenase induces a migratory phenotype in colorectal cancer cells. Exp. Cell Res. · 2012
- Reciprocal regulation of 12- and 15-lipoxygenases by UV-irradiation in human keratinocytes. FEBS Lett. · 2008
- Oxidative metabolism of a fatty acid amide hydrolase-regulated lipid, arachidonoyltaurine. Biochemistry · 2008
- Oxidative metabolism of lipoamino acids and vanilloids by lipoxygenases and cyclooxygenases. Arch. Biochem. Biophys. · 2007
- Platelet 12-lipoxygenase Arg261Gln polymorphism: functional characterization and association with risk of esophageal squamous cell carcinoma in combination with COX-2 polymorphisms. Pharmacogenet. Genomics · 2007
- Associations of functional polymorphisms in cyclooxygenase-2 and platelet 12-lipoxygenase with risk of occurrence and advanced disease status of colorectal cancer. Carcinogenesis · 2007
- … and 16 more in the literature graph