[Features of nuclear genome transcription at early steps of liver regeneration: expression of DNA fractions with different repeating sequence frequencies].

The mode of hybridization of dRNA fraction from normal and regenerating rat liver with purified fractions of repeating and unique sequences of DNA was studied. In order to repress the reassociation of DNA the nucleic acids were annealed in a solution of 2 x SSC--80% formamide at 48 degrees. The differential hybridization curves suggest that the amount of transcripts with a high DNA sequence frequency increases, while the complexity of transcripts of unique DNA sequences decreases 3 hrs after partial hepatectomy. Simultaneously the amount of RNA transcribed from the unique and moderately repeating DNA fractions remains practically unchanged.