» Articles » PMID: 30233407

An Insect Prostaglandin E Synthase Acts in Immunity and Reproduction

Overview
Journal Front Physiol
Date 2018 Sep 21
PMID 30233407
Citations 17
Authors
Affiliations
Soon will be listed here.
Abstract

Eicosanoids, oxygenated metabolites of C20 polyunsaturated fatty acids (PUFAs), mediate fundamental physiological processes, including immune reactions and reproduction, in insects. Prostaglandins (PGs) make up one group of eicosanoids, of which PGE is a relatively well-known mediator in various insect taxa. While PG biosynthesis has been reported, the specific biosynthetic pathway for PGE is not known in insects. Here, we posed the hypothesis that mediates biosynthesis of physiologically active PGE through its cognate protein. To test this hypothesis, we interrogated a transcriptome of the lepidopteran insect, , to identify a candidate PGE synthase () and analyzed its sequence and expression. Its predicted amino acid sequence contains a consensus thioredoxin homology sequence (Cys-x-x-Cys) responsible for catalytic activity along with an N-terminal membrane-associated hydrophobic domain and C-terminal cytosolic domain. It also shares sequence homology (36.5%) and shares almost overlapping three dimensional structures with a membrane-bound human PGES2 (mPGES2). was expressed in all developmental stages with high peaks during the late larval instar and adult stages. Immune challenge significantly up-regulated its expression levels in hemocytes and fat body. Injecting double-stranded RNA (dsRNA) specific to significantly impaired two cellular immune responses, hemocyte-spreading behavior and nodule formation following bacterial challenge. Humoral immunity was also significantly suppressed, registered as reduced phenoloxidase activity and antimicrobial peptide expression levels. The suppressed immune responses were reversed following PGE, but not arachidonic acid (AA), treatments. RNAi treatments also reduced the egg-laying behavior of females. Control females mated with the RNAi-treated males led to substantially reduced egg-laying behavior, which was also reversed following PGE injections into females. These results strongly bolster our hypothesis that acts in the biosynthesis of PGE, a crucial biochemical signal mediating immune and reproductive physiology of .

Citing Articles

Functional characterization of eicosanoid signaling in development.

Fujinaga D, Nolan C, Yamanaka N bioRxiv. 2025; .

PMID: 39868285 PMC: 11761813. DOI: 10.1101/2025.01.13.632770.


The Altered Lipid Composition and Key Lipid Metabolic Enzymes in Thiacloprid-Resistant , with Special Attention Paid to the Function of .

Hu J, Rao W, Chen F, Zhou X, Wang J, Lin L Int J Mol Sci. 2024; 25(22).

PMID: 39596181 PMC: 11594901. DOI: 10.3390/ijms252212112.


A PLA2 deletion mutant using CRISPR/Cas9 coupled to RNASeq reveals insect immune genes associated with eicosanoid signaling.

Vatanparast M, Esmaeily M, Stanley D, Kim Y PLoS One. 2024; 19(7):e0304958.

PMID: 39018338 PMC: 11253937. DOI: 10.1371/journal.pone.0304958.


The Toxicity Differences of Fluralaner against the Red Imported Fire Ant () at Different Developmental Stages.

Shao L, Wang W, Gong X, Yu Y, Xue J, Zeng X Int J Mol Sci. 2023; 24(21).

PMID: 37958611 PMC: 10649654. DOI: 10.3390/ijms242115627.


Profiling lipidomic changes in dengue-resistant and dengue-susceptible strains of Colombian Aedes aegypti after dengue virus challenge.

Elliott K, Caicedo P, Haunerland N, Lowenberger C PLoS Negl Trop Dis. 2023; 17(10):e0011676.

PMID: 37847671 PMC: 10581493. DOI: 10.1371/journal.pntd.0011676.


References
1.
Cerenius L, Soderhall K . The prophenoloxidase-activating system in invertebrates. Immunol Rev. 2004; 198:116-26. DOI: 10.1111/j.0105-2896.2004.00116.x. View

2.
Kanaoka Y, Ago H, Inagaki E, Nanayama T, Miyano M, Kikuno R . Cloning and crystal structure of hematopoietic prostaglandin D synthase. Cell. 1997; 90(6):1085-95. DOI: 10.1016/s0092-8674(00)80374-8. View

3.
Shrestha S, Kim Y . Eicosanoids mediate prophenoloxidase release from oenocytoids in the beet armyworm Spodoptera exigua. Insect Biochem Mol Biol. 2007; 38(1):99-112. DOI: 10.1016/j.ibmb.2007.09.013. View

4.
OGG C . Prostaglandin biosynthesis by fat body from the tobacco hornworm, Manduca sexta. Insect Biochem Mol Biol. 1994; 24(5):481-91. DOI: 10.1016/0965-1748(94)90043-4. View

5.
Eichner C, Overgard A, Nilsen F, Dalvin S . Molecular characterization and knock-down of salmon louse (Lepeophtheirus salmonis) prostaglandin E synthase. Exp Parasitol. 2015; 159:79-93. DOI: 10.1016/j.exppara.2015.09.001. View