title: Sympatric Drosophila simulans flies with distinct mtDNA show difference in mitochondrial respiration and electron transport.
abstract: The role of mitochondrial DNA (mtDNA) in mitochondrial metabolism is understudied yet humans harboring specific mtDNA types age at dissimilar rates, are unequally susceptible to various diseases, and differentially adapt to various environmental conditions. This study compares mitochondrial respiration, proton leak and electron transport of Drosophila simulans males with distinct mtDNA haplogroups (siII and -III) that were collected in sympatry in Kenya. Despite the large divergence among haplogroups there is very low intrahaplogroup variation and no correlated variation in the nuclear genome has been detected. We show that repeatable bioenergetic differences exist between 11d old males harboring siII and siIII mtDNA. Males with siIII mtDNA showed higher (i) state 3 respiration rates from isolated mitochondria for both complex I and complex III based substrates, and (ii) complex IV (cytochrome c oxidase) activity. Males harboring siIII mtDNA had lower (i) hydrogen peroxide formation by both complexes I and III, (ii) proton leak from isolated mitochondria, (iii) mitochondrial ATPase activity, and (iv) mitochondrial cytochrome content. In combination, the results suggest that mitochondria isolated from siIII mtDNA harboring males have more efficient metabolism than siII mtDNA harboring males.
authors.affiliation: Ramaciotti Centre for Gene Function Analysis, School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney 2052, Australia.
authors.forename: Subhash D
authors.initials: SD
authors.lastname: Katewa
authors.forename: J William O
authors.initials: JW
authors.lastname: Ballard
mesh_terms: D000251:Adenosine Triphosphatases / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D003580:Cytochromes / Q000378:metabolism; D004272:DNA, Mitochondrial / Q000235:genetics; D004330:Drosophila / Q000166:cytology / Q000235:genetics* / Q000378:metabolism*; D029721:Drosophila Proteins / Q000378:metabolism; D004579:Electron Transport; D042967:Electron Transport Complex I / Q000378:metabolism; D014450:Electron Transport Complex III / Q000378:metabolism; D004734:Energy Metabolism; D005260:Female; D006239:Haplotypes; D006861:Hydrogen Peroxide / Q000378:metabolism; D007630:Kenya; D008297:Male; D008928:Mitochondria / Q000235:genetics / Q000378:metabolism*; D010101:Oxygen Consumption
chemical_list: D003580:Cytochromes; D004272:DNA, Mitochondrial; D029721:Drosophila Proteins; D000255:Adenosine Triphosphate; D006861:Hydrogen Peroxide; D000251:Adenosine Triphosphatases; D042967:Electron Transport Complex I; D014450:Electron Transport Complex III