Balanced mitochondrial function at low temperature is linked to cold adaptation inDrosophilaspecies

• DOI: 10.1242/jeb.245439
• Publication Date: 2023-03-20T14:15:28Z
• Authors: Lisa Bjerregaard ...; Andrea Milena Hansen; Quentin Willot; Johannes Overgaard
• Keywords: Ectotherm; Cold hardening; Hibernation; Oligomycin

ABSTRACT The ability of ectothermic animals to live in different thermal environments is closely associated with their capacity maintain physiological homeostasis across diurnal and seasonal temperature fluctuations. For chill-susceptible insects, such as Drosophila, cold tolerance tightly linked ion water obtained through a regulated balance active passive transport. Active transport at low requires constant delivery ATP we therefore hypothesize that cold-adapted Drosophila are characterized by superior mitochondrial relative cold-sensitive species. To address this, investigated how experimental temperatures from 1 19°C affected substrate oxidation flight muscle seven species compared it measure (CTmin, the inducing coma). Mitochondrial oxygen consumption rates measured using substrate–uncoupler–inhibitor titration (SUIT) protocol showed cooling generally reduced electron system species, was expected given thermodynamic effects. Complex I respiration primary consumer non-stressful temperatures, but decreases complex much greater extent than Accordingly, cold-induced reduction correlates strongly CTmin. contribution other substrates (proline, succinate glycerol 3-phosphate) increased decreased, particularly At present, unclear whether alternative can be used offset effects temperature-sensitive I, potential functional consequences switch discussed.