Variations in mitochondrial DNA and gene transcription in freezing-tolerant larvae of Eurosta solidaginis (Diptera: Tephritidae) and Gynaephora groenlandica (Lepidoptera: Lymantriidae).
Respiration, mitochondrial (mt)DNA content, and mitochondrial-specific RNA expression in fat body cells from active and cold-adapted larvae of the goldenrod gall fly, Eurosta solidaginis, and the Arctic woolly bear caterpillar, Gynaephora groenlandica, were compared. Reduced amounts of mtDNA were observed in cold-adapted larvae of both E. solidaginis and G. groenlandica collected in fall or winter, compared with summer-collected larvae. mtDNA increased to levels similar to those of summer-collected larvae after incubation at 10 degrees C or 15 degrees C for 5 h. Mitochondrial-specific RNAs (COI and 16S) were observed in fat body cells of both active and cold-adapted E. solidaginis larvae. Our results suggest that mitochondrial proteins required for respiration may be restored rapidly from stable RNAs present in overwintering larvae.
Levin
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DB
Department of Biology, University of Victoria, Victoria, B.C., Canada. dlevin@uvic.ca
Danks
H V
HV
Barber
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SA
D000064:Acclimatization / Q000502:physiology*; D000818:Animals; D001110:Arctic Regions; D003080:Cold Temperature; D004272:DNA, Mitochondrial / Q000235:genetics* / Q000378:metabolism; D003576:Electron Transport Complex IV / Q000235:genetics / Q000378:metabolism; D015971:Gene Expression Regulation, Enzymologic; D007915:Lepidoptera / Q000235:genetics / Q000378:metabolism*; D008928:Mitochondria / Q000235:genetics / Q000378:metabolism*; D009864:Ontario; D010101:Oxygen Consumption / Q000502:physiology; D012336:RNA, Ribosomal, 16S / Q000235:genetics / Q000378:metabolism; D033621:Tephritidae / Q000235:genetics / Q000378:metabolism*
D004272:DNA, Mitochondrial; D012336:RNA, Ribosomal, 16S; D003576:Electron Transport Complex IV