Biopolym. Cell. 1988; 4(3):145-150.
Cell Biology
Extrachromosomal DNA in brain and liver cells of normal rats
1Obukhova L. V., 1Kiseleva E. V., 1Borovkov A. Yu., 1Kumarev V. P., 1Khristolyubova N. B.
  1. Institute of Cytology and Genetics, Siberian Branch of the Academy of Sciences of the USSR
    Novosibirsk, USSR


Three forms of extrachromosomal DNA were revealed in the brain and liver cells of normal rats: supercoiled, relaxed circular and folded rosette-like molecules. Supercoiled DNA was obtained only from liver cells. The relaxed circular forms have different length in brain (0.2–2 μm) and liver (0.2–1μm) cells. 25 % of relaxed circular molecules in liver have the length of 0.2 μm. DNA molecules of the length more than 1 μm have a folded rosette-like form and were the same in brain and liver cells.


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