Energetics of Insect Diapause

Department of Entomology and Nematology, University of Florida, Gainesville, Florida 32611, USA.
Annual Review of Entomology (Impact Factor: 13.73). 01/2011; 56(1):103-21. DOI: 10.1146/annurev-ento-112408-085436
Source: PubMed


Managing metabolic resources is critical for insects during diapause when food sources are limited or unavailable. Insects accumulate reserves prior to diapause, and metabolic depression during diapause promotes reserve conservation. Sufficient reserves must be sequestered to both survive the diapause period and enable postdiapause development that may involve metabolically expensive functions such as metamorphosis or long-distance flight. Nutrient utilization during diapause is a dynamic process, and insects appear capable of sensing their energy reserves and using this information to regulate whether to enter diapause and how long to remain in diapause. Overwintering insects on a tight energy budget are likely to be especially vulnerable to increased temperatures associated with climate change. Molecular mechanisms involved in diapause nutrient regulation remain poorly known, but insulin signaling is likely a major player. We also discuss other possible candidates for diapause-associated nutrient regulation including adipokinetic hormone, neuropeptide F, the cGMP-kinase For, and AMPK.

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Available from: Daniel A Hahn
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    • "Moths from investigated assemblage will undoubtedly increase their winter activity as a consequence of more periods with higher temperatures, as compared to insects in which dormancy is controlled hormonally and depends on the photoperiod. It must affect their reproductive success, as warmer winters reduce the energy reserves needed for post-winter reproduction (Hahn and Denlinger, 2011; Williams et al., 2012). "
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    • "Diapause is a programmed arrest of development that is controlled by endogenous physiological factors and may or may not involve depression of metabolism (Lees, 1955; Tauber and Tauber, 1976; Podrabsky and Hand, 1999; Denlinger, 2002; Reynolds and Hand, 2009; MacRae, 2010; Clegg, 2011; Hahn and Denlinger, 2011; Hand et al., 2011; Patil et al., 2013). Diapause typically precedes the onset of adverse environmental conditions, and production of diapausing embryos is often induced by environmental factors that offer reliable cues for predicting future conditions, such as photoperiod or food quality/availability. Depending on the developmental stage, diapause may be hormonally regulated and occur in response to signaling factors that come before the adverse period. "
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    • "Many insects survive low temperatures during winter in a state of diapause, an adaptation that affords protection from low temperatures and prevents insects from beginning the transition to the next stage (Hahn and Denlinger 2011). Early resumption of development may occur as climate changes, because earlier spring thaws are expected (Inouye 2008). "
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