Non-Cellular Response of Flour Moth, Ephestia kuehniella Challenged with Bacillus thuringiensis and Beauveria bassiana

Document Type : Complete paper

Authors

1 Department of Plant Protection, College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran

2 , Department of Plant Protection, College of Agriculture and Natural Resources, University of Tehran,, Karaj, Iran

Abstract

The innate immune system of insects comprises both cellular and humoral mechanisms. The phenoloxidase activity and the production of antimicrobial peptides/ proteins (AMPs) are the most important parts of insect immune system. In this study, we investigated the humoral response of flour moth, Ephestia kuehniella challenged with two different entomopathogens, Bacillus thuringiensis (Bt) and Beauveria bassiana. The suspension of Bt and/or B. bassiana was injected to the fifth instar larvae of E. kuehniella. Afterwards, the phenoloxidase activity and the possible induction of AMPs in the haemolymph of treated larvae was assessed. Moreover, the antimicrobial activity of the collected haemolymph was examined against a Bt strain. As a result, the phenoloxidase activity of treated larvae was significantly reduced in comparison to non-treated larvae. Also, no band has been detected corresponding to insect AMPs in the haemolymph of immune-challenged larvae with both bacterial and fungal pathogens. Furthermore, the haemolymph did not show any antimicrobial activity in vitro against the tested Bt strain. Based on our findings, it can be concluded that the non-cellular immune system of flour moth did not respond to the cell walls of applied entomopathogens, thus further investigations are needed to determine the possible application of E. kuehniella as a model in the insect immune system studies against these two entomopathogens.

Keywords


Adamski Z, Bufo SA, Chowański S, Falabella P, Lubawy J, Marciniak P, Pacholska-Bogalska J, Salvia R, Scrano L, Słocinska M, Spochacz M, Szymczak M, Urbanski A, Walkowiak-Nowicka K, Rosinski G (2019)Beetles as model organisms in physiological, biomedical and environmental studies - A review. Frontiers in Physiology 10: 319.
Brown SE, Howard A, Kasprzak AB, Gordon KH, East PD (2008) The discovery and analysis of a diverged family of novel antifungal moricin-like peptides in the wax moth Galleria mellonella. Insect Biochemistry and Molecular Biology 38(2): 201–212.
Cerenius L, Lee BL, Söderhäll K (2008)The proPO-system: pros and cons for its role in invertebrate immunity. Trends in Immunology 29(6): 263-71.
Cytryńska M, Mak P, Zdybicka-Barabas A, Suder P, Jakubowicz T (2007) Purification and characterization of eight peptides from Galleria mellonella immune hemolymph. Peptides 28(3): 533-546.
Hung SY, Boucias DG (1992) Influence of Beauveria bassiana on the cellular defense Response of the Beet armyworm, Spodoptera exigua. Journal of Invertebrate Pathology 60(2): 152-8.
 
Kopácek P, Weise C, Götz P (1995) The prophenoloxidase from the wax moth Galleria mellonella: purification and characterization of the proenzyme. Insect Biochemistry and Molecular Biology 25(10):1081–91.
Lavine MD, Strand MR (2002) Insect Hemocytes and Their Role in Immunity. Insect Biochemistry and Molecular Biology 32(10): 1295-309.
Li S, Xu X, Shakeel M, Xu J, Zheng Z, Zheng J, Yu X, Zhao Q, Jin F (2018) Bacillus thuringiensis suppresses the humoral immune system to overcome defense mechanism of Plutella xylostella. Frontiers in Physiology 15(9): 1478.
Lin J, Yu XQ, Wang Q, Tao X, Li J, Zhang S, Xia X, You M (2020). Immune responses to Bacillus thuringiensis in the midgut of the diamondback moth, Plutella xylostella. Developmental & Comparative Immunology 103661.
Lu Z, Jiang H (2007) Regulation of phenoloxidase activity by high- and lowmolecular-weight inhibitors from the larval hemolymph of Manduca sexta. Insect Biochemistry and Molecular Biology 37: 478–485.
Rahimi VA, Zibaee AR, Mojahed SA, Maddahi KH, Zare DA (2013) Effects of pyriproxyfen and hexaflumuron on cellular immunity of Ephestia kuehniella Zeller (Lepidoptera: Pyralidae). Romanian Journal of Biology-Zoology 58(2): 151-62.
Schägger H (2006)Tricine–SDS-PAGE.Nature Protocol1(1):16-22.
Taszłow P, Vertyporokh L, Wojda I (2017) Humoral immune response of Galleria mellonella after repeated infection with Bacillus thuringiensis. Journal of invertebrate pathology 1(149): 87-96.
Tzou P, De Gregorio E, Lemaitre B (2002) How Drosophila combats microbial infection: a model to study innate immunity and host–pathogen interactions. Current Opinion in Microbiology. 5(1): 102-10.
Xu J, Xu X, Shakeel M, Li S, Wang S, Zhou X, Yu J, Xu Xi, Yu X, Jin F (2017). The Entomopathogenic Fungi Isaria fumosorosea plays a vital role in suppressing the immune system of Plutella xylostella: RNA-Seq and DGE analysis of immunity-related genes. Frontiers in Microbiology 8.
Zhao P, Li J, Wang Y, Jiang H (2007)Broad-spectrum antimicrobial activity of the reactive compounds generated in vitro by Manduca sexta phenoloxidase. Insect Biochemistry and Molecular Biology 37: 952–959.
Zibaee A, Bandani AR, Malagoli D(2011) Purification and characterization of phenoloxidase from the hemocytes of Eurygaster integriceps (Hemiptera: Scutelleridae). Comparative Biochemistry and Physiology Part B: Biochemistry and Molecular Biology 158(1): 117-123.