Host: The Japanese Society of Plant Physiologists
Pages 0229
Mitochondrial-nucleus is defined as DNA-protein complex of mitochondria, and regarded as the site in which various functions of mitochondrial genomes, such as DNA replication, transcription, are conducted. To understand how these various functions are performed within highly organized structure, identification and characterization of the proteins responsible for the organization of mitochondrial-nuclei are necessary. So, we examined the structural organization of plant mitochondrial-nuclei and the proteins involved in the organization, by using BY-2 cultured tobacco cells. Experiments with isolated mitochondrial-nuclei treated with various agents suggested that the structure of mitochondrial-nuclei is retained by electrostatic interaction between DNA and proteins, and mitochondrial DNA form nucleosome-like structures within mitochondrial-nuclei. Treatment with increasing concentration of NaCl caused gradual dispersion of mitochondrial-nuclei and gradual dissociation of proteins from mitochondrial DNA. Then, we explored DNA-binding proteins in those solubilized by NaCl treatment. At present, in order to identify these proteins, they are analyzed by mass spectrometry.
