Variations in mitochondrial DNA and gene transcription in freezing-tolerant larvae of Eurosta solidaginis (Diptera: Tephritidae) and Gynaephora groenlandica (Lepidoptera: Lymantriidae)

• Published in: Insect molecular biology Vol. 12; no. 3; pp. 281 - 289
• Main Authors: Levin, D.B, Danks, H.V, Barber, S.A
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Science Ltd 01.06.2003
• Subjects: 16s ribosomal RNA; 16S rRNA; Acclimatization - physiology; adaptation; Animals; Arctic Regions; Arctic woolly bear; caterpillar; cell respiration; Cold Temperature; cold tolerance; cold-hardiness; cytochrome oxidase; cytochrome oxidase I; cytochrome-c oxidase; DNA; DNA, Mitochondrial - genetics; DNA, Mitochondrial - metabolism; Electron Transport Complex IV - genetics; Electron Transport Complex IV - metabolism; Eurosta solidaginis; fat body; freezing; gene expression; Gene Expression Regulation, Enzymologic; goldenrod gall fly; insect adaptation; larvae; Lepidoptera - genetics; Lepidoptera - metabolism; Lymantriidae; messenger RNA; mitochondria; Mitochondria - genetics; Mitochondria - metabolism; molecular sequences data; mRNA; mtDNA; nucleotide sequences; Ontario; oxygen consumption; Oxygen Consumption - physiology; respiration rate; ribosomal RNA; RNA, Ribosomal, 16S - genetics; RNA, Ribosomal, 16S - metabolism; seasonal variation; summer; Tephritidae - genetics; Tephritidae - metabolism; transcription (genetics); winter; Arctic Regions; Ontario
• ISSN: 0962-1075; 1365-2583
• DOI: 10.1046/j.1365-2583.2003.00413.x

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 °C or 15 °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.