Characterization of Female Reproductive Proteases in a Butterfly from Functional and Evolutionary Perspectives

• DOI: 10.1086/705722
• Publication Date: 2019-08-02T18:54:37Z
• Authors: Melissa S. Plakke; Jennifer L. Walker; Jeffrey B. Lombardo; Breanna J. Goetz; Gina N. Pacella; Jacob D. Durrant; Nathan L. Clark; Nathan I. Morehouse
• Keywords: Spermatophore; Protease inhibitor (pharmacology); Cysteine protease

Molecules that mediate reproductive interactions are some of the most rapidly evolving traits. Researchers have often suggested this is due to coevolution at key physiological interfaces. However, very few these interfaces well understood functional level. One such interface digestion spermatophore in Lepidoptera. Female Lepidoptera a specialized organ called bursa copulatrix receives and processes male spermatophore, complex proteinaceous ejaculate. In cabbage white butterfly, Pieris rapae, secretes mixture proteases hypothesized digest spermatophore. remain biochemically uncharacterized. Using zymogram approach, we identified six bursal extracts sufficiently high concentrations characterize their vitro activity. We assessed modes action enzymes by quantifying activity following exposure diagnostic protease inhibitors. A serine protease-specific inhibitor failed reduce casein. cysteine did decrease proteases. To explore possible molecular mechanisms responsible for responses, created homology models. The models mirrored results our experiments, indicating may offer insight into underlying mechanisms. Whether observed resistance known inhibitors important context remains be tested. suggest exciting possibility specificity evolved response with various proteins present within female tract during process.