CYP2U1 (cytochrome P450, family 2, subfamily U, polypeptide 1) is a
protein
Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residue (biochemistry), residues. Proteins perform a vast array of functions within organisms, including Enzyme catalysis, catalysing metab ...
that in humans is encoded by the ''CYP2U1''
gene
In biology, the word gene has two meanings. The Mendelian gene is a basic unit of heredity. The molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protei ...
Function
This gene encodes a member of the
cytochrome P450
Cytochromes P450 (P450s or CYPs) are a Protein superfamily, superfamily of enzymes containing heme as a cofactor (biochemistry), cofactor that mostly, but not exclusively, function as monooxygenases. However, they are not omnipresent; for examp ...
superfamily of enzymes. The cytochrome P450 proteins are
monooxygenase
Monooxygenases are enzymes that incorporate one hydroxyl group (−OH) into substrates in many metabolic pathways. In this reaction, the two atoms of dioxygen are reduced to one hydroxyl group and one H2O molecule by the concomitant oxidation of ...
s which catalyze many reactions involved in drug metabolism and synthesis of cholesterol, steroids and the hydroxylation of fatty acids and fatty acid metabolites.
CYP2U1 metabolized
arachidonic acid
Arachidonic acid (AA, sometimes ARA) is a polyunsaturated omega−6 fatty acid 20:4(ω−6), or 20:4(5,8,11,14). It is a precursor in the formation of leukotrienes, prostaglandins, and thromboxanes.
Together with omega−3 fatty acids an ...
,
docosahexaenoic acid
Docosahexaenoic acid (DHA) is an omega−3 fatty acid that is an important component of the human brain, cerebral cortex, skin, and retina. It is given the fatty acid notation 22:6(''n''−3). It can be synthesized from alpha-linolenic acid or ...
(DHA), and other long chain
fatty acid
In chemistry, in particular in biochemistry, a fatty acid is a carboxylic acid with an aliphatic chain, which is either saturated and unsaturated compounds#Organic chemistry, saturated or unsaturated. Most naturally occurring fatty acids have an ...
s which suggests that CYP2U1 may play a role in brain and immune functions.
CYP2U1 also metabolizes
propanone
Acetone (2-propanone or dimethyl ketone) is an organic compound with the chemical formula, formula . It is the simplest and smallest ketone (). It is a colorless, highly Volatile organic compound, volatile, and flammable liquid with a charact ...
,
acetone
Acetone (2-propanone or dimethyl ketone) is an organic compound with the chemical formula, formula . It is the simplest and smallest ketone (). It is a colorless, highly Volatile organic compound, volatile, and flammable liquid with a charact ...
, and 2-oxypropane.
Tissue distribution
The CYP2U1 gene is a highly conserved gene that is mainly expressed in brain and thymus, but also at lower levels in kidney, lung, and heart.
Reactions
CYP2U1 hydroxylates
arachidonic acid
Arachidonic acid (AA, sometimes ARA) is a polyunsaturated omega−6 fatty acid 20:4(ω−6), or 20:4(5,8,11,14). It is a precursor in the formation of leukotrienes, prostaglandins, and thromboxanes.
Together with omega−3 fatty acids an ...
,
docosahexaenoic acid
Docosahexaenoic acid (DHA) is an omega−3 fatty acid that is an important component of the human brain, cerebral cortex, skin, and retina. It is given the fatty acid notation 22:6(''n''−3). It can be synthesized from alpha-linolenic acid or ...
(DHA), and other long chain
fatty acid
In chemistry, in particular in biochemistry, a fatty acid is a carboxylic acid with an aliphatic chain, which is either saturated and unsaturated compounds#Organic chemistry, saturated or unsaturated. Most naturally occurring fatty acids have an ...
s at their terminal (i.e., ω) carbon to form 20-hydroxy-arachidonic acid (i.e.
20-Hydroxyeicosatetraenoic acid or 20-HETE), 22-hydroxy-docosahexaneoic acid, and other ω-hydroxy long chain fatty acids, respectively, plus lesser amounts of these fatty acids ω-1 hydroxy metabolites, i.e. 19-HETE, 21-hydroxy-docosahexaenoic acid, and other ω-1 hydroxy long chain fatty acids, respectively.
One of these metabolites, 20-HETE, is a regulator of blood pressure and blood flow to organs in animal models and, based on genetic studies, possibly in humans (see
20-Hydroxyeicosatetraenoic acid).
Clinical significance
A mutation (c.947A>T) in CYP2U1 has been associated in a very small number of patients with
hereditary spastic paraplegia
Hereditary spastic paraplegia (HSP) is a group of inherited diseases whose main feature is a progressive Gait abnormality, gait disorder. The disease presents with progressive stiffness (spasticity) and contraction in the lower limbs. HSP is als ...
in that it segregates with the disease at the homozygous state in two afflicted families. This mutation affects an amino acid (p.Asp316Val) that is highly conserved among CYP2U1
orthologs
Sequence homology is the biological homology between DNA, RNA, or protein sequences, defined in terms of shared ancestry in the evolutionary history of life. Two segments of DNA can have shared ancestry because of three phenomena: either a spec ...
as well as other cytochrome P450 proteins; this p.Asp314Val mutation is located in the enzyme's functional domain, is predicted to be damaging to the enzyme's activity, and is associated with
mitochondria
A mitochondrion () is an organelle found in the cells of most eukaryotes, such as animals, plants and fungi. Mitochondria have a double membrane structure and use aerobic respiration to generate adenosine triphosphate (ATP), which is us ...
dysfunction.
A second homozygous enzyme-disabling mutation has been identified in CYP2U1, c.1A>C/p.Met1?, that is associated with <1% of hereditary spastic paraplegia sufferers.
The reduction in 20-HETE production by these mutations, and thereby in 20-HETE's activation of the
TRPV1
The transient receptor potential cation channel subfamily V member 1 (TRPV1), also known as the capsaicin receptor and the vanilloid receptor 1, is a protein that, in humans, is encoded by the ''TRPV1'' gene. It was the first isolated member of ...
neural receptor, it is hypothesized, may contribute to the development of this disease (see
20-Hydroxyeicosatetraenoic acid for details).
CYPU21 along with members of the CYP4A and CYP4F sub-families also ω-hydroxylate and thereby reduce the activity of various fatty acid metabolites of arachidonic acid including
LTB4,
5-HETE
5-Hydroxyeicosatetraenoic acid (5-HETE, 5(''S'')-HETE, or 5''S''-HETE) is an eicosanoid, i.e. a metabolite of arachidonic acid. It is produced by diverse cell types in humans and other animal species. These cells may then metabolize the formed 5(' ...
,
5-oxo-eicosatetraenoic acid,
12-HETE, and several
prostaglandins
Prostaglandins (PG) are a group of physiologically active lipid compounds called eicosanoids that have diverse hormone-like effects in animals. Prostaglandins have been found in almost every tissue in humans and other animals. They are derive ...
that are involved in regulating various inflammatory, vascular, and other responses in animals and humans. This hydroxylation-induced inactivation may underlie the proposed roles of the cytochromes in dampening inflammatory responses and the reported associations of certain CYP4F2 and CYP4F3
single nucleotide variants with human
Krohn's disease and
Coeliac disease
Coeliac disease (British English) or celiac disease (American English) is a long-term autoimmune disorder, primarily affecting the small intestine. Patients develop intolerance to gluten, which is present in foods such as wheat, rye, spelt ...
, respectively.
References
External links
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Further reading
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{{Cytochrome P450
Cytochrome P450