View Program - 63rd Annual Drosophila Research Conference

Entomopathogenic nematodes (EPNs) are insect-parasitic nematodes which kill insects quickly on infection. EPNs from the genus Steinernema release excretory/secretory proteins (ESPs) into the insect host at the early stages of infection and these ESPs are toxic to insects. These proteins actively participate in tissue damage and immunomodulation of the host during infection. One of these proteins is an ShKT-domain-containing protein. ShKT-domain-containing proteins are named after the venom of sea anemone Stichodactyla helianthus. The ShKT domain is found in diverse groups of animal venoms and forms a large group of family called the ShK superfamily. They are known as a potent K⁺ channel blocker and perform many critical roles in animal venoms e.g., immunomodulator, neurotoxic, paralytic, hemolytic, etc. Our goal is to study the function of the ShKT protein from S. carpocapsae nematode and characterize its role in host-parasite interactions. We generated a recombinant version of ShKT protein using yeast expression system. To characterize the activity of the protein, we used the fruit fly (Drosophila melanogaster) model system. We injected 100 ng of purified ShKT protein into fruit flies and observed ~50% mortality. In addition to mortality, we evaluated additional health metrics of the fruit flies using behavioral assays (negative geotaxis and chill coma recovery). We found that the health of fruit flies was significantly affected by the ShKT protein.

ShKT-domain-containing protein from parasitic nematode is toxic to Drosophila melanogaster