Extrachromosomal circular ribosomal DNA in the yeast Saccharomyces carlsbergensis

نویسندگان

  • J. H. Meyerink
  • J. Klootwijk
  • R. Planta
  • A. van der Ende
  • E. F. van Bruggen
چکیده

Purified ribosomal DNA from Saccharomyces carlsbergensis contains a small proportion of circular DNA molecules with a contour length of 3 micron or integral multiples thereof. Hybridization of yeast ribosomal DNA with 26 S rRNA, using the R-loop technique, reveals that these circular molecules contain sequences complementary to yeast ribosomal RNA. We suggest that these extrachromosomal rRNA genes may be intermediates in the amplification of rRNA genes in yeast.

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عنوان ژورنال:
  • Nucleic acids research

دوره 7 1  شماره 

صفحات  -

تاریخ انتشار 1979