Plant mitochondria actively import DNA via the permeability transition pore complex.
Plant mitochondria are remarkable with respect to their content in foreign, alien and plasmid-like DNA, raising the question of the transfer of this information into the organelles. We demonstrate the existence of an active, transmembrane potential-dependent mechanism of DNA uptake into plant mitochondria. The process is restricted to double-strand DNA, but has no obvious sequence specificity. It is most efficient with linear fragments up to a few kilobase pairs. When containing appropriate information, imported sequences are transcribed within the organelles. The uptake likely involves the voltage-dependent anion channel and the adenine nucleotide translocator, i.e. the core components of the mitochondrial permeability transition pore complex in animal cells, but it does not rely on known mitochondrial membrane permeabilization processes. We conclude that DNA import into plant mitochondria might represent a physiological phenomenon with some functional relevance.
Koulintchenko
Milana
M
Institut de Biologie Moléculaire des Plantes du CNRS, Université Louis Pasteur, 12 rue du Général Zimmer, 67084 Strasbourg, France.
Konstantinov
Yuri
Y
Dietrich
André
A
D001693:Biological Transport, Active; D002463:Cell Membrane Permeability / Q000502:physiology*; D018744:DNA, Plant / Q000737:chemistry / Q000378:metabolism*; D007473:Ion Channels; D007700:Kinetics; D008564:Membrane Potentials; D008928:Mitochondria / Q000235:genetics / Q000378:metabolism*; D033681:Mitochondrial Membrane Transport Proteins; D000083162:Mitochondrial Permeability Transition Pore; D018272:Porins / Q000378:metabolism; D011198:Solanum tuberosum / Q000502:physiology*; D014158:Transcription, Genetic; D050994:Voltage-Dependent Anion Channels
D018744:DNA, Plant; D007473:Ion Channels; D033681:Mitochondrial Membrane Transport Proteins; D000083162:Mitochondrial Permeability Transition Pore; D018272:Porins; D050994:Voltage-Dependent Anion Channels