Human mitochondrial DNA is packaged with TFAM

Nucleic Acids Res. 2003 Mar 15;31(6):1640-5. doi: 10.1093/nar/gkg251.

Abstract

Mitochondrial transcription factor A (TFAM), a member of the high mobility group proteins, is essential for maintenance of mitochondrial DNA (mtDNA). Most TFAM and mtDNA (both of which are normally soluble) was recovered from the particulate fraction of human placental mitochondria when extracted with the non-ionic detergent Nonidet P-40. mtDNA and TFAM were co-immunoprecipitated by anti-TFAM antibodies. TFAM was released into the supernatant by DNase I digestion of mtDNA in the particulate fraction. Thus, TFAM and mtDNA are tightly associated with each other, and it is likely that few TFAM or mtDNA molecules exist in an unbound form in mitochondria. Based on the fact that TFAM is abundant enough to wrap mtDNA entirely, these results suggest that human mtDNA is packaged with TFAM.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • DNA, Mitochondrial / genetics
  • DNA, Mitochondrial / isolation & purification
  • DNA, Mitochondrial / metabolism*
  • DNA-Binding Proteins*
  • Deoxyribonuclease I / metabolism
  • Female
  • HeLa Cells
  • Humans
  • Immunohistochemistry
  • Mitochondria / chemistry
  • Mitochondria / metabolism
  • Mitochondrial Proteins*
  • Nuclear Proteins*
  • Octoxynol
  • Polyethylene Glycols / chemistry
  • Polymerase Chain Reaction
  • Precipitin Tests
  • Protein Binding
  • Solubility
  • Sonication
  • Trans-Activators*
  • Transcription Factors / isolation & purification
  • Transcription Factors / metabolism*
  • U937 Cells
  • Xenopus Proteins*

Substances

  • DNA, Mitochondrial
  • DNA-Binding Proteins
  • Mitochondrial Proteins
  • Nuclear Proteins
  • TFAM protein, human
  • Trans-Activators
  • Transcription Factors
  • XL-MTTFA protein, Xenopus
  • Xenopus Proteins
  • mitochondrial transcription factor A
  • Polyethylene Glycols
  • Octoxynol
  • Nonidet P-40
  • Deoxyribonuclease I