Disease relevance of PTGFRN

• This idea was tested through attempts to construct viruses encoding the immunoglobulin loop 6 and transmembrane regions of the prostaglandin F2alpha receptor regulatory protein (FPRP), a product that inhibits adenovirus vector construction for reasons that are not clear [1].

High impact information on PTGFRN

• Confocal microscopy analysis revealed that EWI-2 and EWI-F colocalized with ERM proteins at microspikes and microvilli of adherent cells and at the cellular uropod in polarized migrating leukocytes [2].
• EWI-2 and EWI-F link the tetraspanin web to the actin cytoskeleton through their direct association with ezrin-radixin-moesin proteins [2].
• CD9P-1 was also shown to form separate complexes with CD81 and with an unidentified 175-kDa molecule [3].
• Cross-linking experiments detected a complex of the size of CD9 plus CD9P-1, showing that these glycoproteins directly associate with each other, probably in the absence of any other molecule [3].
• Although CD81 associated with both alpha(3) integrin and FPRP in 293 cells, the alpha(3)beta(1).CD81 and CD81.CD9.FPRP complexes were distinct, as determined by immunoprecipitation and immunodepletion experiments [4].

Biological context of PTGFRN

• The human fprp gene was first socalized through human/rodent somatic cell hybrids to human chromosome 1 (100% concordance), and further through yeast artificial chromosome (YAC) pools to region 1p13.1-q21.3 (level 1 mapping) [5].
• This inhibition of [3H]PGF2 alpha binding by FPRP occurs only when the FPRP cDNA is expressed in the same cell as the FP resides, reaches a maximum of approximately 80%, and is unaffected by second messenger perturbing agents such as phorbol ester, 8-Br-cAMP, calcium ionophore A23187, and okadaic acid [6].

Anatomical context of PTGFRN

• We have previously identified a 135-kDa molecule (CD9P-1) as a major molecular partner of CD9 in cancer cell lines [3].
• Both EWI-2 and CD9P-1 were detected in the human liver at the surface of hepatocytes and were found to associate with CD81 on freshly isolated hepatocytes [7].
• Expression of the FPRP cDNA in COS cells results in production of a full length (approximately 130 kD) immunoreactive molecule with an endoplasmic reticulum and Golgi network distribution similar to that seen in granulosa lutein cells [6].
• Transient expression of an FPRP cDNA in undifferentiated 3T3-L1 cells was insufficient to induce lipid droplet accumulation [8].
• FPRP mRNA and protein are also found in rat adipose tissue [8].

Associations of PTGFRN with chemical compounds

• Histologically, this protein (FP regulatory protein or FPRP) shows a distribution coinciding well with those cells and tissues that respond to PGF2alpha [5].
• One of the most prominent proteins within CD81 and CD9 complexes is identified here as FPRP, the 133-kDa prostaglandin F(2alpha) receptor regulatory protein [4].
• FPRP, a transmembrane glycoprotein, has been shown to regulate the binding of ligand to certain seven-transmembrane receptors [8].
• Differentiation induction with either dexamethasone/insulin/isobutylmethylxanthine or the thiazolidinedione derivative ADD 4743 were both effective at inducing FPRP accumulation and accumulation of lipid droplets [8].
• Treatment of 3T3-L1 cells with an FPRP anti-sense oligonucleotide during differentiation decreased FPRP accumulation and resulted in a decrease in lipid droplets without altering the level of induction of a late marker of adipocyte differentiation, glycerol-3-phosphate dehydrogenase activity [8].

Analytical, diagnostic and therapeutic context of PTGFRN

• A portion of the 3' untranslated region of the human homolog to fprp was subcloned, sequenced, and oligonucleotide primers chosen that allow polymerase chain reaction (PCR) amplification specifically of the human fprp sequence [5].
• Immunoprecipitation studies showed the association of EWI-2 and EWI-F with ERM proteins in vivo [2].
• Molecular dissection of the FPRP protein indicates that two portions of the molecule play a role in the inhibition of FP [6].
• Anti-FPRP immunohistochemistry, Western blotting, and metabolic labeling/immunoprecipitation experiments demonstrated that FPRP was not detectable in undifferentiated 3T3-L1 cells [8].

References