Resource competition affects the developmental outcome of the acoustic parasitoid fly Ormia ochracea

Dominguez, J. A.; Latham, B.; Mongui, L. C.; Rossinow, A.; Xiong, Y.; Schmidt, B. V.; Vu, Q.; Torres-Lopez, B. L.; Hendserson, P. A.; Mason, A. C.; Lee, N.

doi:10.1101/2024.04.25.590943

bioRxiv · 10.1101/2024.04.25.590943

Resource competition affects the developmental outcome of the acoustic parasitoid fly Ormia ochracea

Dominguez, J. A.·Latham, B.·Mongui, L. C.·Rossinow, A.·Xiong, Y.·Schmidt, B. V.·Vu, Q.·Torres-Lopez, B. L.·Hendserson, P. A.·Mason, A. C.·Lee, N.

View original source ↗Export metadata ↓

Abstract

Ormia ochracea is an acoustic parasitoid fly where the adults are free-living, but their larval young depend on nutritional resources within host crickets for growth and development. In nature, gravid female flies rely on their ability to recognize and localize cricket calling songs to find suitable host species to parasitize. In depth investigations of fly behavior and the mechanistic bases of auditory perception require a reliable approach to propagate stable fly colonies in the laboratory. Previous work has demonstrated that flies can be propagated using a number of natural host cricket species, as well as cricket species that flies do not parasitize in nature. However, we lack a complete understanding of fly developmental outcomes when non-host cricket species are utilized to propagate fly colonies. In this study, we document the feasibility of using commercially supplied Acheta domesticus as a host species. We specifically test the hypothesis that host size and resource competition can affect developmental outcomes of O. ochracea. We performed manual parasitizations on crickets that varied in size, and resource competition was varied by manipulating the number of larvae used to parasitize a host cricket. A series of morphometric analyses were conducted on host crickets, and developmental outcomes were measured in terms of pupation success and eclosion success, pupal width, and eclosed adult fly size. In the absence of resource competition, we found that host cricket size did not affect pupation or eclosion success. In the presence of resource competition between two developing larvae within a host cricket, pupation and eclosion successes were impacted negatively, and the developing pupae were more likely to be smaller. These results confirm that resource competition among developing parasitoids can negatively affect developmental outcomes, and Acheta domesticus can be used effectively to propagate colonies of O. ochracea in the laboratory. HighlightsO_LIThe acoustic parasitoid fly Ormia ochracea can successfully develop within the house cricket Acheta domesticus. C_LIO_LIPupal size and eclosed adult fly size varies positively with the size of host cricket. C_LIO_LIResource competition negatively affects pupation and eclosion success. C_LIO_LIResource competition resulted in smaller fly pupae that were less likely to eclose. C_LI Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=192 HEIGHT=200 SRC="FIGDIR/small/590943v1_ufig1.gif" ALT="Figure 1"> View larger version (40K): org.highwire.dtl.DTLVardef@b86e19org.highwire.dtl.DTLVardef@44444corg.highwire.dtl.DTLVardef@1dfe813org.highwire.dtl.DTLVardef@fd5b3b_HPS_FORMAT_FIGEXP M_FIG C_FIG

Source connections

Published article ↗

Explore related subjects

physiology Preprint

Keep this discovery

Explore connections, maps & timelines

BibTeX RIS

Dominguez, J. A., Latham, B., Mongui, L. C., Rossinow, A., Xiong, Y., Schmidt, B. V., Vu, Q., Torres-Lopez, B. L., Hendserson, P. A., Mason, A. C., Lee, N.. 2024-04-28. Resource competition affects the developmental outcome of the acoustic parasitoid fly Ormia ochracea. https://doi.org/10.1101/2024.04.25.590943

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related preprints

bioRxiv2026

The canine hair metabolome encodes age and coat exposure in over 700 dogs

Hair can be collected noninvasively and stored for years, making it a practical sample for studying physiology and environmental exposure. Yet the chemical information it carries in dogs remains largely unexplored. We profiled 782 banked hair samples from 700 Golden Retrievers by untargeted liquid chromatography-mass spectrometry, detecting 4,533 compound groups and revealing an unexpectedly rich chemical profile. Prominent signals reflected skin-surface and hair chemistry, including amino acids, peptides and urocanic acid, alongside surfactants, plasticizers and pesticides detectable despite washing. A signal annotated as imidacloprid distinguished dogs receiving topical products containing this insecticide from dogs receiving no flea or tick preventive (AUC 0.865). Hair chemistry also varied with age, most strongly between puppyhood and early adulthood. Oxidized lipids generally declined, whereas amino acids and peptides remained largely stable. A multivariate model estimated age with moderate accuracy (cross-validated r = 0.66) and assigned a higher age to the later sample in 64 of 75 repeatedly sampled dogs. Because age and collection date were strongly correlated, their effects could not be fully separated, although date-restricted analyses supported an age-related contribution. Together, these findings establish banked dog hair as a promising resource for studying chemical exposure and life-stage-associated changes in chemistry.

physiology↗

bioRxiv2026

Dietary Human HSP90 Promotes Longevity and Healthspan in Caenorhabditis elegans via a Multi-Branched Stress Signaling Pathway

The loss of proteostasis is one of the primary drivers of aging. Despite the important role of the molecular chaperone HSP90 in maintaining proteostasis, its systemic role in aging appears contradictory because its inhibitors can effectively extend lifespan across diverse species. This study showed that dietary HSP90 supplementation via Escherichia coli significantly extended lifespan and healthspan of Caenorhabditis elegans without fertility trade-offs. Exogenous HSP90 likely acts as an extracellular signaling ligand that engages downstream kinase networks to drive the activation of three major longevity-associated transcription factors: DAF-16, SKN-1, and HSF-1. In addition, we demonstrated the additive effect of combining dietary HSP90 supplementation with the senolytic HSP90 inhibitor tanespimycin, indicating that extracellular proteostatic signaling and the intracellular inhibition of HSP90 can work together to enhance longevity. Finally, we engineered an antibiotic-free E. coli Nissle 1917 probiotic that constitutively expresses HSP90, which successfully extended the lifespan of C. elegans.

physiology↗

bioRxiv2026

Sex differences in myocardial ketone oxidation capacity in cardiometabolic disease with coincident ischemic heart disease

Background: Myocardial infarction (MI) in patients with heart failure with preserved ejection fraction (HFpEF) is associated with worse outcomes than MI in individuals without HFpEF. However, the molecular mechanisms underlying this increased vulnerability remain poorly understood. We investigated sex differences in cardiac ketone body (KB) metabolism in patients with diabetes-associated ischemic heart disease, and in a mouse model of HFpEF complicated by MI (HFpEF-MI). Methods: Cardiac BDH1 and OXCT1 expression was assessed in male and female patients with diabetes, with or without ischemic heart disease. Male and female mice received a high-fat diet and L-NAME for 10 weeks to induce HFpEF, followed by coronary artery ligation to induce MI. Glucose tolerance, cardiac function, survival, cardiac KB oxidative capacity, and circulating KB levels were evaluated. Results: Cardiac BDH1 and OXCT1 abundance was significantly reduced in male patients with diabetes-associated ischemic heart disease but preserved in female patients. In mice, 10 weeks of high-fat diet and L-NAME administration increased fasting blood glucose and impaired glucose tolerance. MI reduced systolic function in control and HFpEF mice of both sexes. Male HFpEF-MI mice exhibited higher mortality than female HFpEF-MI mice. Consistent with our human results, male HFpEF-MI mice showed reduced cardiac ketolytic enzyme expression alongside elevated circulating KB levels, whereas female mice maintained cardiac KB oxidative capacity. Conclusion: Reduced cardiac ketolytic enzyme expression and impaired KB oxidative capacity are associated with greater mortality in male HFpEF-MI mice, whereas female mice exhibit preserved KB oxidative capacity and improved survival. Similar sex differences in ketolytic enzyme expression were observed in patients with diabetes-associated ischemic heart disease. These findings identify cardiac ketone metabolism as a potential therapeutic target warranting further investigation in HFpEF complicated by MI.

physiology↗