Prostaglandin-H2 D-isomerase (PTGDS) is an
enzyme
Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrates, and the enzyme converts the substrates into different molecules known as products. A ...
that in humans is encoded by the ''PTGDS''
gene
In biology, the word gene (from , ; "...Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''birth'' or ''gender'') can have several different meanings. The Mendelian gene is a ba ...
.
Function
The protein encoded by this gene is a glutathione-independent prostaglandin D synthase that catalyzes the conversion of
prostaglandin H2 (PGH
2) to
prostaglandin D2 (PGD
2). PGD
2 functions as a neuromodulator as well as a trophic factor in the central nervous system. PGD
2 is also involved in smooth muscle contraction/relaxation and is a potent inhibitor of platelet aggregation. This gene is preferentially expressed in brain. Studies with transgenic mice over-expressing this gene suggest that this gene may be also involved in the regulation of non-rapid eye movement sleep.
Furthermore, PTGDS and its product PGD
2 are elevated in the bald-scalp areas of men with male pattern baldness (
androgenetic alopecia
In botany, apomixis is asexual reproduction without fertilization. Its etymology is Greek for "away from" + "mixing". This definition notably does not mention meiosis. Thus "normal asexual reproduction" of plants, such as propagation from cutti ...
).
Clinical use
Prostaglandin D
2 synthase is used clinically as a diagnostic marker for
liquorrhea, that is, to check whether fluid leaking from the nose or ear contains
cerebrospinal fluid
Cerebrospinal fluid (CSF) is a clear, colorless body fluid found within the tissue that surrounds the brain and spinal cord of all vertebrates.
CSF is produced by specialised ependymal cells in the choroid plexus of the ventricles of the bra ...
.
This is important in the assessment of
head trauma
A head injury is any injury that results in trauma to the skull or brain. The terms ''traumatic brain injury'' and ''head injury'' are often used interchangeably in the medical literature. Because head injuries cover such a broad scope of inju ...
severity. In a medical context, the older term "beta-trace protein" is frequently used to refer to PTGDS.
See also
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Hematopoietic prostaglandin D synthase
References
Further reading
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External links
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Lipocalins
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