InterPro : IPR002972

Name  Prostaglandin D synthase Short Name  PstgldnD_synth
Type  Family Description  The lipocalins are a diverse, interesting, yet poorly understood family of proteins composed, in the main, of extracellular ligand-binding proteinsdisplaying high specificity for small hydrophobic molecules [, ]. Functionsof these proteins include transport of nutrients, control of cell regulation, pheromone transport, cryptic colouration and the enzymatic synthesisof prostaglandins.The crystal structures of several lipocalins have been solved and show a novel 8-stranded anti-parallel beta-barrel fold well conserved within thefamily. Sequence similarity within the family is at a much lower level andwould seem to be restricted to conserved disulphides and 3 motifs, whichform a juxtaposed cluster that may act as a common cell surface receptorsite []. By contrast, at the more variable end of the fold are found an internal ligand binding site and a putative surface for the formation of macromolecular complexes []. The anti-parallel beta-barrel fold is alsoexploited by the fatty acid-binding proteins (which function similarly bybinding small hydrophobic molecules), by avidin and the closely relatedmetalloproteinase inhibitors, and by triabin. Similarity at the sequence level, however, is less obvious, being confined to a single short N-terminal motif.The lipocalin family can be subdivided into kernal and outlier sets. Thekernal lipocalins form the largest self consistent group, comprising the subfamily of prostaglandin D synthases. The outlier lipocalins form several smaller distinct subgroups: the OBPs, the von Ebner's gland proteins, alpha-1-acid glycoproteins, tick histamine binding proteins and the nitrophorins.Glutathione-independent prostaglandin D (PGD2) synthase () is themain factor involved in synthesis of PGD2 in the brain, accounting for over90% of activity in the rat; it is responsible for catalysing the conversionof PGH2 into PGD2 in the presence of various thiol compounds. PGD2 isa major prostaglandin in mammalian brains, functioning in the central nervous system as both a neuromodulator and a trophic factor. The enzymaticactivity of PGD synthase makes it unique among the lipocalins. It is localised in the choroid plexus, meninges and oligodendrocytes, but is also a major component of cerebrospinal fluid. Immunocytochemistry indicates thatthe protein is associated with the rough endoplasmic reticulum and the outernuclear membranes of rat oligodendrocytes, and seems to be a peripheral membrane protein easily dissociated by detergents.A near homologue of PGD2 synthase has been identified in cane-toad (Bufo marinus) choroid plexus, where it is the most abundant protein secreted intothe cerebrospinal fluid []. It is also found in other areas of the brain,albeit at much lower levels, and is expressed throughout amphibian metamorphosis. The choroid plexus helps form the barrier between blood and cerebrospinal fluid, and it has been suggested that this lipocalin may help transport lipophilic molecules across the blood/brain barrier.

Sequence Features

GO Displayer


InterPro protein domain ID --> Contigs



0 Child Features

1 Contains

Id Name Short Name Type
IPR022272 Lipocalin family conserved site Lipocalin_CS Conserved_site

0 Found In

1 Parent Features

Id Name Short Name Type
IPR002345 Lipocalin Lipocalin Family

4 Publications

First Author Title Year Journal Volume Pages
Flower DR Multiple molecular recognition properties of the lipocalin protein family. 1995 J Mol Recognit 8 185-95
Pervaiz S Homology of beta-lactoglobulin, serum retinol-binding protein, and protein HC. 1985 Science 228 335-7
Flower DR The lipocalin protein family: structure and function. 1996 Biochem J 318 ( Pt 1) 1-14
Achen MG Protein synthesis at the blood-brain barrier. The major protein secreted by amphibian choroid plexus is a lipocalin. 1992 J Biol Chem 267 23170-4

To cite PlanMine, please refer to the following publication:

Rozanski, A., Moon, H., Brandl, H., Martín-Durán, J. M., Grohme, M., Hüttner, K., Bartscherer, K., Henry, I., & Rink, J. C.
PlanMine 3.0—improvements to a mineable resource of flatworm biology and biodiversity
Nucleic Acids Research, gky1070. doi:10.1093/nar/gky1070 (2018)