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. 1973 Oct;70(10):2926–2930. doi: 10.1073/pnas.70.10.2926

The Amplification of Ribosomal RNA Genes Involves a Rolling Circle Intermediate

Dennis Hourcade 1, David Dressler 1, John Wolfson 1
PMCID: PMC427140  PMID: 4517945

Abstract

During the development of Xenopus oocytes there is a special DNA synthesis that leads to a thousandfold amplification of the genes that code for ribosomal RNA. We have used the electron microscope to study this process. Our primary observation is the presence of ribosomal DNA in rolling-circle intermediates at the time of amplification. We believe that these intermediates are involved in the amplification process, and as such offer the first example of the involvement of a rolling circle in the replication of eukaryotic DNA.

Keywords: DNA replication, Xenopus laevis, gene amplification, repetitive DNA, electron microscopy of DNA

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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