Experimental assessment of bioenergetic differences caused by the common European mitochondrial DNA haplogroups H and T.
(2008)
Journal - Gene (Netherlands )
Abstract :
Studies of both survival after sepsis and sperm motility in human populations have shown significant associations with common European mitochondrial DNA haplogroups, and have led to proposals that mitochondria bearing haplogroup H have different bioenergetic capacities than those bearing haplogroup T. However, the validity of such associations assumes that there are no non-random influences of nuclear genes or other factors. Here, we removed the effect of any differences in nuclear genes by constructing transmitochondrial cybrids harbouring mitochondria with either haplogroup H or haplogroup T in cultured A549 human lung carcinoma cells with identical nuclear backgrounds. We compared the bioenergetic capacities and coupling efficiencies of mitochondria isolated from these cells, and of mitochondria retained within the cells, as a critical experimental test of the hypothesis that these haplogroups affect mitochondrial bioenergetics. We found that there were no functionally-important bioenergetic differences between mitochondria bearing these haplogroups, using either isolated mitochondria or mitochondria within cells.
| ISSN : | 0378-1119 |
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| Mesh Heading : | Cell Line, Tumor DNA, Mitochondrial European Continental Ancestry Group Genetic Variation Haplotypes Humans Hybrid Cells Membrane Potential, Mitochondrial |
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| Mesh Heading Relevant : | Oxidative Phosphorylation Oxygen Consumption metabolism genetics |
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Were inefficient mitochondrial haplogroups selected during migrations of modern humans? A test using modular kinetic analysis of coupling in mitochondria from cybrid cell lines.
(2007)
Journal - The Biochemical journal (England )
Abstract :
We introduce a general test of the bioenergetic importance of mtDNA (mitochondrial DNA) variants: modular kinetic analysis of oxidative phosphorylation in mitochondria from cybrid cells with constant nuclear DNA but different mtDNA. We have applied this test to the hypothesis [Ruiz-Pesini, Mishmar, Brandon, Procaccio and Wallace (2004) Science 303, 223-226] that particular mtDNA haplogroups (specific combinations of polymorphisms) that cause lowered coupling efficiency, leading to generation of less ATP and more heat, were positively selected during radiations of modern humans into colder climates. Contrary to the predictions of this hypothesis, mitochondria from Arctic haplogroups had similar or even greater coupling efficiency than mitochondria from tropical haplogroups.
| ISSN : | 1470-8728 |
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| Mesh Heading : | Animals Arctic Regions Catalase Cell Line, Tumor DNA, Mitochondrial Evolution Humans Hybrid Cells Kinetics Membrane Potentials Mice Oxidative Phosphorylation metabolism metabolism |
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| Mesh Heading Relevant : | Haplotypes Travel genetics |
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Were inefficient mitochondrial haplogroups selected during migrations of modern humans? A test using modular kinetic analysis of coupling in mitochondria from cybrid cell lines
(2007)
Journal - Biochemical Journal
Abstract :
We introduce a general test of the bioenergetic importance of mtDNA (mitochondrial DNA) variants: modular kinetic analysis of oxidative phosphorylation in mitochondria from cybrid cells with constant nuclear DNA but different mtDNA. We have applied this test to the hypothesis [Ruiz-Pesini, Mishmar, Brandon, Procaccio and Wallace (2004) Science 303, 223–226] that particular mtDNA haplogroups (specific combinations of polymorphisms) that cause lowered coupling efficiency, leading to generation of less ATP and more heat, were positively selected during radiations of modern humans into colder climates. Contrary to the predictions of this hypothesis, mitochondria from Arctic haplogroups had similar or even greater coupling efficiency than mitochondria from tropical haplogroups.
| ISSN : | 0264-6021 |
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| Keywords : | coupling efficiency,cybrid,human evolution,mitochondrial DNA (mtDNA),modular kinetic analysis,oxidative phosphorylation |
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