Molecular characterization of prostaglandin F receptor (FP) and E receptor subtype 3 (EP3) in chickens

Abstract

Prostaglandin E and F regulate diverse physiological functions including gastrointestinal motility, fever induction and reproduction. This multitude of biological effects is mediated via their four E receptor subtypes (EP(1), EP(2), EP(3) and EP(4)) and F receptor (FP), respectively. Majority of these studies was performed in mammalian species, while investigations on their roles were impeded by inadequate information on their receptors in avian species. In present study, full-length cDNAs of chicken EP(3) (cEP(3)) and two isoforms of FP - cFPa and cFPb - were cloned from adult hen ovary. The putative cEP(3) and cFPa share high amino acid sequence identity with their respective orthologs, while the predicted cFPb is a novel middle-truncated splice variant which lacks 107 amino acids between transmembrane domains 4 and 6. RT-PCR showed that cEP(3), cFPa and cFPb are widely expressed in adult tissues examined, including ovary and oviduct. Using a pGL3-CRE luciferase reporter system, cEP(3)-expressing DF1 cells inhibited forskolin-induced luciferase activity (EC(50): <1.9 pM) upon PGE(2) treatment, suggesting that cEP(3) may functionally couple to Gi protein. Upon PGF(2α) addition, cFPa was shown to potentially couple to intracellular Ca(2+)-signaling pathway by pGL3-NFAT-RE reporter assay (EC(50): 2.9 nM), while cFPb showed no response. Using a pGL4-SRE reporter system, both cEP(3) and cFPa exhibited potential MAPK activation by PGE(2) and PGF(2α) at EC(50) 0.34 and 13 nM, respectively. Molecular characterization of these receptors paved the road to the better understanding of PGE(2) and PGF(2α) roles in avian physiology and comparative endocrinology studies.

Replication of Marek's Disease Virus Is Dependent on Synthesis of De Novo Fatty Acid and Prostaglandin E 2

“…5A). Chicken EP2, EP3, and EP4 receptors have been cloned and characterized (15, 16), while EP1 receptor has not yet been identified in chickens. Analysis of gene expression in the mock- and MDV-infected CEFs demonstrated that the EP2 and EP4, but not EP3, receptors were upregulated upon MDV infection (Fig.…”

Distribution of EP4 receptor in different Atlantic salmon (Salmo salar L.) tissues

“…EP receptors of the zebrafish are the best studied among fish species and have only been characterized recently. All the four different EP subtypes are present in zebrafish and two isoforms of EP2, three of EP1 and EP4, and five of EP3 were characterized Kwok et al, 2012;Tsuge et al, 2013). Analysis of the different zebrafish EP amino acid sequences revealed 40-70% sequence identity to their human counterparts.…”

“…Analysis of the different zebrafish EP amino acid sequences revealed 40-70% sequence identity to their human counterparts. In all subtypes, the seven transmembrane regions are conserved and most of the differences are in the extra and intracellular loops Kwok et al, 2012;Tsuge et al, 2013). However, the distribution of these receptors or their functions in different tissues has not yet been studied in detail.…”

Targeted induction ofde novoFatty acid synthesis enhances MDV replication in a COX-2/PGE2αdependent mechanism through EP2 and EP4 receptors engagement

“…Four different types of PGE 2α receptors have been identified in humans are EP1, EP2, EP3, and EP4. Chicken EP2, EP3, and EP4 receptors have been cloned and characterized [31, 32] while chicken EP1 receptor has not yet been identified. Analysis of gene expressions in the MDV-infected and mock-infected CEFs demonstrated that the EP2 and EP4 receptors were significantly up-regulated in cells infected with MDV (Fig 6J), suggesting that PGE 2α may support MDV replication through an EP2 or/and EP4 mediated mechanisms.…”