National and Kapodistrian University of Athens
Department of Biology
Biophysics & Bioinformatics Laboratory
Protein Information |
|
|---|---|
| Protein Name | Polyunsaturated fatty acid 5-lipoxygenase |
| Accession Code | P51399 |
| Gene | ALOX5 |
| Organism | Mesocricetus auratus | Golden hamster (Taxonomy: 10036) |
| Part of Reference Proteome? | Yes |
| Sequence (Length: 673) |
Description |
Position in the Nuclear Envelope |
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|---|---|---|
| Location | Location ID | Description |
| Nuclear Envelope | SL-0178 | The nuclear envelope is a membrane system which surrounds the nucleoplasm of eukaryotic cells. It is composed of the nuclear lamina, nuclear pore complexes and two nuclear membranes. The space between the two membranes is called the nuclear intermembrane space. |
| Nuclear Membrane | SL-0182 | The membrane surrounding the nucleus. This term is used when it is not known if the protein is found in or associated with the inner or outer nuclear membrane. |
| Nuclear Intermembrane Space | SL-0184 | The nuclear intermembrane space is the space between the inner and outer nuclear membranes. |
| Perinuclear Region | SL-0198 | The perinuclear region is the cytoplasmic region just around the nucleus. | Membrane Topology |
| Topology | Source | Annotation Type |
| Peripheral | UniProt | By Similarity {ECO:0000250|UniProtKB:P09917} | Assigned Ontology terms |
Description |
|
|---|---|
| Catalyzes the oxygenation of arachidonate to 5- hydroperoxyeicosatetraenoate (5-HPETE) followed by the dehydration to 5,6- epoxyeicosatetraenoate (Leukotriene A4/LTA4), the first two steps in the biosynthesis of leukotrienes, which are potent mediators of inflammation. Also catalyzes the oxygenation of arachidonate into 8- hydroperoxyicosatetraenoate (8-HPETE) and 12- hydroperoxyicosatetraenoate (12-HPETE). Displays lipoxin synthase activity being able to convert (15S)-HETE into a conjugate tetraene. Although arachidonate is the preferred substrate, this enzyme can also metabolize oxidized fatty acids derived from arachidonate such as (15S)-HETE, eicosapentaenoate (EPA) such as (18R)- and (18S)-HEPE or docosahexaenoate (DHA) which lead to the formation of specialized pro- resolving mediators (SPM) lipoxin and resolvins E and D respectively, therefore it participates in anti-inflammatory responses (By similarity). Oxidation of DHA directly inhibits endothelial cell proliferation and sprouting angiogenesis via peroxisome proliferator- activated receptor gamma (PPARgamma). It does not catalyze the oxygenation of linoleic acid and does not convert (5S)-HETE to lipoxin isomers. In addition to inflammatory processes, it participates in dendritic cell migration, wound healing through an antioxidant mechanism based on heme oxygenase-1 (HO-1) regulation expression, monocyte adhesion to the endothelium via ITGAM expression on monocytes. Moreover, it helps establish an adaptive humoral immunity by regulating primary resting B cells and follicular helper T cells and participates in the CD40-induced production of reactive oxygen species (ROS) after CD40 ligation in B cells through interaction with PIK3R1 that bridges ALOX5 with CD40. May also play a role in glucose homeostasis, regulation of insulin secretion and palmitic acid-induced insulin resistance via AMPK. Can regulate bone mineralization and fat cell differentiation increases in induced pluripotent stem cells (By similarity). {By SimilarityUniProtKB:P09917, By SimilarityUniProtKB:P48999}. | Assigned Ontology terms |
Database | Links |
| UNIPROT | P51399 |
| Pfam | PF00305 PF01477 |
| PROSITE | PS00711 PS00081 PS51393 PS50095 |
National and Kapodistrian University of Athens
Department of Biology
Biophysics & Bioinformatics Laboratory