Date of Award


Document Type


Degree Name

Master of Science (MS)


School of Biological Sciences

First Advisor

Nathan Mortimer

Second Advisor

Tom Hammond


Leptopilina heterotoma is a generalist endoparasitoid wasp that parasitizes Drosophila spp. worldwide. When L. heterotoma oviposits within the prey larvae it also injects venom to suppress the melanotic encapsulation immune response of the host. Without the venom to protect the egg(s) from host immunity, the parasitism would result in failure. L. heterotoma venom is composed of proteins, non-protein compounds, and virus-like particles (VLPs), of which proteins make up the majority of the venom and are the main determining factor conferring venom function (Goecks et al. 2013, Heavner et al. 2013, Moreau and Asgari 2015, Small et al. 2012). Previous studies focus on adaptation of the parasitoid venom. Plastic responses and subsequent adaptations come as a result of environmental changes, the most notable of which is access to different hosts. However, these previous studies fail to take into account the plastic response of the parasitoid. In order to remedy this knowledge gap, an initial generation of L. heterotoma was reared on Drosophila melanogaster. Then the initial generation was used to establish 3 replicates reared on Drosophila melanogaster and 3 replicates reared on Drosophila yakuba. Each generation’s venom was analyzed for alterations in venom protein production, venom content, and relative protein abundance. Total venom protein was quantified using a Bradford Assay, and variations in venom protein content and relative abundance was analyzed using SDS-PAGE gels, gradient gels, ImageJ, and SAS analytics software. It was found that the total protein quantity produced was not significantly affected by the change in host availability but specific proteins within bands 11, 3, 2, and 8 were significantly impacted by the change in host availability. This is indicative that L. heterotoma’s plastic response strategy to a new host is to change the quantity of specific proteins rather than increase the overall quantity of proteins.


Imported from Fuss_ilstu_0092N_12470.pdf


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