Leukotriene C4 synthase
Encyclopedia
Leukotriene C4 synthase is an enzyme
that in humans is encoded by the LTC4S gene
.
The protein encoded by this gene, LTC4S (or glutathione S-transferase II) is an enzyme that converts leukotriene A4
and glutathione
to create leukotriene C4
. This is a member of MAPEG family
of transmembrane protein
s. A trimer of Leukotriene C4 synthase is localized on the outer nuclear membrane and endoplasmic reticulum
, where it forms a complex with 5-Lipoxygenase-activating protein. This protein is remotely related to microsomal glutathione S-transferase
.
(Membrane-Associated Proteins in Eicosanoid and Glutathione metabolism) family includes a number of human proteins, several of which are involved the production of leukotriene
s. This gene encodes an enzyme that catalyzes the first step in the biosynthesis of cysteinyl leukotrienes, potent biological compounds derived from arachidonic acid
. Leukotrienes have been implicated as mediators of anaphylaxis
and inflammatory conditions such as human bronchial asthma. This protein localizes to the nuclear envelope
and adjacent endoplasmic reticulum
.
Enzyme
Enzymes are proteins that catalyze chemical reactions. In enzymatic reactions, the molecules at the beginning of the process, called substrates, are converted into different molecules, called products. Almost all chemical reactions in a biological cell need enzymes in order to occur at rates...
that in humans is encoded by the LTC4S gene
Gene
A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...
.
The protein encoded by this gene, LTC4S (or glutathione S-transferase II) is an enzyme that converts leukotriene A4
Leukotriene A4
Leukotriene A4 is a leukotriene.Leukotriene A4 hydrolase converts it to Leukotriene B4....
and glutathione
Glutathione
Glutathione is a tripeptide that contains an unusual peptide linkage between the amine group of cysteine and the carboxyl group of the glutamate side-chain...
to create leukotriene C4
Leukotriene C4
Leukotriene C4 is a leukotriene....
. This is a member of MAPEG family
MAPEG family
MAPEG family of transmembrane proteins with highly divergent functions...
of transmembrane protein
Transmembrane protein
A transmembrane protein is a protein that goes from one side of a membrane through to the other side of the membrane. Many TPs function as gateways or "loading docks" to deny or permit the transport of specific substances across the biological membrane, to get into the cell, or out of the cell as...
s. A trimer of Leukotriene C4 synthase is localized on the outer nuclear membrane and endoplasmic reticulum
Endoplasmic reticulum
The endoplasmic reticulum is an organelle of cells in eukaryotic organisms that forms an interconnected network of tubules, vesicles, and cisternae...
, where it forms a complex with 5-Lipoxygenase-activating protein. This protein is remotely related to microsomal glutathione S-transferase
Glutathione S-transferase
Enzymes of the glutathione S-transferase family are composed of many cytosolic, mitochondrial, and microsomal proteins. GSTs are present in eukaryotes and in prokaryotes, where they catalyze a variety of reactions and accept endogenous and xenobiotic substrates.GSTs can constitute up to 10% of...
.
Function
The MAPEGMAPEG family
MAPEG family of transmembrane proteins with highly divergent functions...
(Membrane-Associated Proteins in Eicosanoid and Glutathione metabolism) family includes a number of human proteins, several of which are involved the production of leukotriene
Leukotriene
Leukotrienes are fatty signaling molecules. They were first found in leukocytes . One of their roles is to trigger contractions in the smooth muscles lining the trachea; their overproduction is a major cause of inflammation in asthma and allergic rhinitis...
s. This gene encodes an enzyme that catalyzes the first step in the biosynthesis of cysteinyl leukotrienes, potent biological compounds derived from arachidonic acid
Arachidonic acid
Arachidonic acid is a polyunsaturated omega-6 fatty acid 20:4.It is the counterpart to the saturated arachidic acid found in peanut oil, Arachidonic acid (AA, sometimes ARA) is a polyunsaturated omega-6 fatty acid 20:4(ω-6).It is the counterpart to the saturated arachidic acid found in peanut oil,...
. Leukotrienes have been implicated as mediators of anaphylaxis
Anaphylaxis
Anaphylaxis is defined as "a serious allergic reaction that is rapid in onset and may cause death". It typically results in a number of symptoms including throat swelling, an itchy rash, and low blood pressure...
and inflammatory conditions such as human bronchial asthma. This protein localizes to the nuclear envelope
Nuclear envelope
A nuclear envelope is a double lipid bilayer that encloses the genetic material in eukaryotic cells. The nuclear envelope also serves as the physical barrier, separating the contents of the nucleus from the cytosol...
and adjacent endoplasmic reticulum
Endoplasmic reticulum
The endoplasmic reticulum is an organelle of cells in eukaryotic organisms that forms an interconnected network of tubules, vesicles, and cisternae...
.
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