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Mechanisms of Metabolic Cycles in Diapausing Flesh Fly by Metabolomics Approach

ABSTRACT: Insects use diapause, a programmed period of dormancy, to avoid stressful times of the year and to exploit seasonal times of resource availability. Because most diapausing insects do not feed, they must live off their body reserves for several months and the proper use of metabolic reserves is critical for surviving diapause and performing after diapause termination. Across multiple insects, metabolic depression during diapause has been associated with a switch from aerobic metabolism to facultative anaerobic metabolism, despite insects not suffering environmental oxygen limitation. While metabolic rates are depressed during diapause overall to save energy, some insects show regular cyclical bouts of higher metabolic activity during diapause. The functional importance of these metabolic cycles and the mechanisms underlying these cycles are still unknown, but they may be critical for properly maintaining the balance between energy states and purge the accumulation of anaerobic metabolic byproducts. In the present study, we will test the hypothesis that periodic cycles of increased metabolism during insect diapause are associated with both regenerating organismal energetic states, particularly ATP that may decline during metabolic depression, and for purging metabolites associated with anaerobic metabolism. We will use a combination of non-targeted uHPLC-MS/MS metabolomics and targeted NMR-spectroscopy to identify and quantify metabolites that are altered during the cycles in diapausing pupae of the flesh fly, Sarcophaga crassipalpis. This work will allow us to propose specific biochemical and cellular hypotheses for the regulation of cyclic releases from metabolic depression in diapausing insects. Our work may not only reveal the physiological mechanisms regulating metabolic cycles during diapause in flesh fly, but also provide insight to understand the regulation of similar metabolic cycles in mammalian hibernators (i.e., periodic arousal), and also provide insights into how these cycles could be exploited to disrupt the diapause of insect pests.

INSTRUMENT(S): Orbitrap

ORGANISM(S): Flesh Fly Sarcophaga Crassipalpis

TISSUE(S): Whole Insect

SUBMITTER: Chao Chen

PROVIDER: ST000294 | MetabolomicsWorkbench | Tue Mar 03 00:00:00 GMT 2015

REPOSITORIES: MetabolomicsWorkbench

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Mechanisms of Metabolic Cycles in Diapausing Flesh Fly by Metabolomics Approach

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