Repopulation of rho0 cells with mitochondria from a patient with a mitochondrial DNA point mutation in tRNA(Gly) results in respiratory chain dysfunction

Hum Mutat. 1999;13(3):245-54. doi: 10.1002/(SICI)1098-1004(1999)13:3<245::AID-HUMU9>3.0.CO;2-B.


Familial hypertrophic ventricular cardiomyopathy has been demonstrated to be associated with a number of mitochondrial DNA (mtDNA) mutations. A fibroblast cell line carrying a mutation in its mtDNA at position 9997 in the gene encoding tRNA glycine was obtained from a patient with hypertrophic cardiomyopathy. To demonstrate that the etiology of this disease was a result of the mtDNA mutation, cybrid clones were constructed by fusion of enucleated patient skin fibroblasts to rho0 osteosarcoma cells. Clones carrying high levels of mutant mtDNA showed predominantly cytochrome c oxidase and complex I deficiency, as well as an elevated lactate/pyruvate (L/P) ratio, a biochemical marker characteristic of respiratory chain deficiencies. Pulse-labeling experiments demonstrated a strong negative correlation between the levels of newly synthesized mtDNA-encoded polypeptides and glycine content. These data suggest that the T9997C mutation in mtDNA is causative of respiratory chain dysfunction when present at high levels of heteroplasmy.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Blotting, Southern
  • Cardiomyopathy, Hypertrophic / genetics
  • Citrate (si)-Synthase / metabolism
  • DNA, Mitochondrial / genetics*
  • Electron Transport / physiology*
  • Electron Transport Complex II
  • Electron Transport Complex III / metabolism
  • Fibroblasts / enzymology
  • Fibroblasts / metabolism
  • Glycine / metabolism
  • Humans
  • Hybrid Cells
  • Lactic Acid / metabolism
  • Models, Genetic
  • Multienzyme Complexes / metabolism
  • NADH Dehydrogenase / metabolism
  • Oxidoreductases / metabolism
  • Phenotype
  • Point Mutation*
  • Pyruvic Acid / metabolism
  • Quinone Reductases / metabolism
  • RNA, Transfer, Gly / genetics*
  • Succinate Dehydrogenase / metabolism


  • DNA, Mitochondrial
  • Multienzyme Complexes
  • RNA, Transfer, Gly
  • Lactic Acid
  • Pyruvic Acid
  • Oxidoreductases
  • Electron Transport Complex II
  • Succinate Dehydrogenase
  • Quinone Reductases
  • NADH Dehydrogenase
  • Citrate (si)-Synthase
  • Electron Transport Complex III
  • Glycine