Center for Bioinformatics
Oxidoreductases | Transferases | Hydrolases | Lyases | Isomerases | Ligases

Basic Information

Enzyme Number

4.4.1.20

Official Name

leukotriene-C4 synthase

Name from literature

LTC4 synthase

Pathway from literature

formation of cysteinyl leukotrienes

Pathway from KEGG

Lipid Metabolism; Arachidonic acid metabolism; map00590

Organisms

Human (9606)

Genome localization

5q35[4056 ],

Comments

The reaction proceeds in the direction of addition. Not identical with EC 2.5.1.18, glutathione transferase.

Rate-limiting Description

"The rate limiting step in the formation of cysteinyl leukotrienes is the conversion of LTA4 to LTC4 catalyzed by the enzyme LTC4 synthase." (10222453)

Regulatory Information

Upstream transcription factor

6667;6670

Regulatory type

Detail

transcriptional factor;"Sp1(6667),Sp3(6670)"

"Sp1 and Sp3 function as key regulators of leukotriene C(4) synthase gene expression in the monocyte-like cell line, THP-1." (10919991)

key enzyme;

"LTC(4) synthase is a key enzyme in the cys-LT biosynthetic pathway, and studies in small populations have suggested that a promoter polymorphism (A(-444)C) in the gene might be associated with asthma severity and aspirin intolerance." (15131571)

transcriptional factor;"Sp1(6667),Sp3(6670)"

"Gene expression in mononuclear phagocytes is regulated by SP1 and SP3." (12664565)

phosphorylation;

Q16873

Gene ontology

Gene ontology

GO:0004364 (F) glutathione transferase activity [Q16873 ];
GO:0005635 (C) nuclear envelope [Q16873 ];
GO:0019370 (P) leukotriene biosynthetic process [Q16873 ];
GO:0004464 (F) leukotriene-C4 synthase activity [Q16873 ];
GO:0016021 (C) integral to membrane [Q16873 ];
GO:0005792 (C) microsome [Q16873 ];
GO:0008289 (F) lipid binding [Q16873 ];
GO:0008047 (F) enzyme activator activity [Q16873 ];

Tissue expression

Tissue From HPRD

Thymus [02004 ];
Colon [02004 ];
Uterus [02004 ];
Salivary gland [02004 ];
Macrophage [02004 ];
Bone marrow [02004 ];
Skeletal muscle [02004 ];
Liver [02004 ];
Lymph [02004 ];
Alveolar macrophage [02004 ];
Brain [02004 ];
Spleen [02004 ];
Platelet [02004 ];
Kidney [02004 ];
Langerhans cell [02004 ];
Adrenal gland [02004 ];
Monocyte [02004 ];
Granulocyte [02004 ];
Lung [02004 ];
Myeloid stem cell [02004 ];
Skin [02004 ];
Epidermis [02004 ];
Basophil [02004 ];
Trachea [02004 ];
Placenta [02004 ];
Mast cell [02004 ];
Stomach [02004 ];
Pituitary gland [02004 ];
Eosinophil [02004 ];

Tissue specificity

Detected in lung, platelets and the myelogenous leukemia cell line KG-1 (at protein level). LTC4S activity is present in eosinophils, basophils, mast cells, certain phagocytic mononuclear cells, endothelial cells, vascular smooth muscle cells and platelets [Q16873 ];

Subcellular localization

Localization

nucleus [Q16873 ];

membrane [Q16873 ];

Disease relevance

Disease

Defects in LTC4S are the cause of leukotriene C4 synthase deficiency (LTC4 synthase deficiency) [MIM:246530]. LTC4 synthase deficiency is a fatal neurometabolic developmental disorder. It is associated with muscular hypotonia, psychomotor retardation, failure to thrive, and microcephaly [Q16873 ];

Links

SwissProt

Q16873

Entrez Gene

4056

HPRD

02004



  Copyright 2009, Center for Bioinformatics 
  Last Modified: 2009-03-24  
  Design by Zhao Min