Complexity of the cold acclimation response in Drosophila melanogaster

• Published in: Journal of insect physiology Vol. 52; no. 1; pp. 94 - 104
• Main Authors: Rako, Lea, Hoffmann, Ary A.
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 2006
• Subjects: acclimation; Acclimatization - physiology; Animals; body size; Chill coma recovery; Cohort Effect; cold stress; Cold stress acclimation; Cold Temperature - adverse effects; cold tolerance; Drosophila melanogaster; Drosophila melanogaster - physiology; egg hatchability; Female; insect development; maternal effect; Maternal effects; Mortality; physiological response; progeny; Temperature; Maternal effects; Chill coma recovery; Drosophila melanogaster; Cold stress acclimation
• ISSN: 0022-1910; 1879-1611
• DOI: 10.1016/j.jinsphys.2005.09.007

Insects can increase their resistance to cold stress when they are exposed to non-lethal conditions prior to the stress; these plastic responses are normally described only in terms of immediate effects on mortality. Here we examine in Drosophila melanogaster the short- and longer-term effects of different conditions on several measures of cold resistance, but particularly chill coma recovery. Short-term exposure to sublethal temperature (cold hardening) did not decrease chill coma recovery times even though it decreased mortality. Exposure to 12 °C for 2 days (acclimation) decreased chill coma recovery times for a range of stressful temperatures when flies were cultured at 25 °C, but did not usually affect recovery times when flies were cultured at 19 °C. In contrast, 2-day exposure to 12 °C decreased mortality regardless of rearing temperature. Rearing at 19 °C decreased mortality and chill coma recovery time relative to rearing at 25 °C. Acclimation increased the eclosion rate of eggs from stressed females, but did not affect development time or size of the offspring. These results indicate that plastic responses to cold in D. melanogaster are complex when resistance is scored in different ways, and that effects can extend across generations.