The Role of Eicosanoids in Nodulation Reaction Against Entomopathogenic Fungi in Spodoptera littoralis (Boisd.) (Lepidoptera: Noctuidae) Larvae

The study carried out the role of eicosanoids on nodulation reactionsin Spodoptera littoralis larvae, against two fungal isolates(Beauveria bassiana 6646 and Metarhizium anisopliae 3293). Whenthe larvae were infected with Beauveria bassiana 6646 andMetarhizium anisopliae 3293, the insects showed a nodulationreaction to this infection. Injecting eicosanoid biosynthesis inhibitorsjust before the S. littoralis larvae were infected with fungal isolatesreduced the nodulation response to fungal isolates. Specificapplications, including inhibitors of enzymes in eicosanoidbiosynthesis; “dexamethasone (a phospholipase A2 inhibitor),indomethacin, naproxen, ibuprofen (cyclooxygenase inhibitors),esculetin (a lipoxygenase inhibitor) and phenidone (bothcyclooxygenase / lipoxygenase inhibitor) reduced” formation ofnodules in S. littoralis against fungal infection. These findingssupport the hypothesis that eicosanoids are involved in nodulationreactions against fungal infections in larvae of S. littoralis.

Spodoptera littoralis (Boisd.) (Lepidoptera: Noctuidae) Larvalarında Entomopatojenik Funguslara Karşı Nodülasyon Reaksiyonunda Eikosanoidlerin Rolü

Çalışma, iki mantar fungus (Beauveria bassiana 6646 ve Metarhizium anisopliae 3293) karşı, Spodoptera littoralis larvalarındaki nodülasyon reaksiyonları üzerinde eikosanoidlerin rolünü test etmiştir. Larvalar Beauveria bassiana 6646 ve Metarhizium anisopliae 3293 ile enfekte edildiğinde, böcekler bu enfeksiyona karşı nodülasyon reaksiyonu göstermiştir. S. littoralis larvalarına fungus izolatları ile enfekte edilmeden hemen önce eikosanoid biyosentez inhibitörlerinin enjekte edilmesi, fungus izolatlarına nodülasyon tepkisini azaltmıştır. Deksametazon (bir fosfolipaz A2 inhibitörü), indometasin, naproksen, ibuprofen (siklooksijenaz inhibitörleri), esculetin (bir lipooksijenaz inhibitörü) ve fenidon (her ikisi de siklooksijenaz/lipooksijenaz inhibitörü) dahil olmak üzere eikosanoid biyosentezindeki enzim inhibitörleri ile yapılan spesifik uygulamalar. S. littoralis'te fungal enfeksiyonuna karşı nodül oluşumunun azalmasına sebep olmuştur. Bu bulgular, eikosanoidlerin S. littoralis larvalarındaki fungal enfeksiyonlarına karşı nodülasyon reaksiyonlarına dahil olduğu hipotezini desteklemektedir.

PDF

___

Dunn PE 1986. Biochemical aspects of insect immunology. Annual Review Entomology, 31: 321-339.

Gillespie JP, Kanost MR, Trenczek T 1997. Biological mediators of insect immunity. Annual Review of Entomology, 42: 611-643.

Miller JS, Nguyen T, Stanley-Samuelson DW 1994. Eicosanoids mediate insect nodulation responses to bacterial infections. Proceedings of the National Academy of Sciences USA, 91(26): 12418-12422.

Rosales C 2017. Cellular and Molecular Mechanisms of Insect Immunity. In: Shields,V.D.C. Ed. Insect Physiology and Ecology. InTeach Publicaiton. CCBY. Pp. 179-212.

Russell V, Dunn PE 1996. Antibacterial proteins in the midgut of Manduca sexta during metamorphosis. Journal of Insect Physiolology, 42: 65-71.

SAS Institute Inc. 1989. SAS/STATR User's Guide, Version 6, 4th Ed., vol 2. SAS Institute Inc., Cary, NC.

Satyavathi VV, Minz A, Nagaraju J 2014. Nodulation: An unexplored cellular defense mechanism in insects. Cellular Signalling, 26: 1753-1763.

Stanley DW 2000. Eicosanoids in Invertebrate Signal Transduction Systems. Princeton University Press, Princeton, NJ.

Stanley DW, Kim Y 2014. Eicosanoid Signaling in Insects: from Discovery to Plant. Critical Reviews in Plant Sciences, 33(1):20-63.

Stanley DW, Miller JS 2006. Eicosanoid actions in insect cellular immune functions. Entomologia Experimentalis et Applicata, 119:1-13.

Tunaz H 2006. Influence of Eicosanoids in nodulation reactions against bacteria, Serratia marcescens in larvae of Leptinotarsa decemlineata. KSU Fen Mühendislik Dergisi, 9:159-163.

Tunaz H, Bengin C, Er MK 2008. Nodulation reaction to fungal infections in larvae of Leptinotarsa decemlineata(Say) (Coleoptera: Chrysomelidae) mediated by eicosanoids. Turkish Journal of Agricultural Forestry, 32: 11-18.

Tunaz H, Işıkber AA, Er MK 2018. Blatella germenica'nın erginlerinde iki fungal izolata karşı eikozanoidlerin nodülasyon reaksiyonları üzerine olan fonksiyonu. KSÜ Tarım ve Doğa Dergisi, 21(3): 428-432.