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Proceedings of the National Academy of Sciences of the United States of America logoLink to Proceedings of the National Academy of Sciences of the United States of America
. 1972 Jan;69(1):139–142. doi: 10.1073/pnas.69.1.139

Evidence of Gene Diminution During the Formation of the Macronucleus in the Protozoan, Stylonychia*

C J Bostock 1,, D M Prescott 1
PMCID: PMC427562  PMID: 4500545

Abstract

The course of events by which a macronucleus is formed from a micronucleus after conjugation in the ciliated protozoan, Stylonychia, suggests that genetic diminution may occur. This idea is supported by determinations of the density profiles and melting curves for micro- and macronuclear DNAs. Macronuclear DNA consists of a single density component and melts as if it were a single component. Micronuclear DNA consists of four or more density components and melts as if it were a mixture of several DNAs of different base compositions. These data indicate that at least 60% of the micronuclear DNA components are absent from the macronuclear DNA.

Keywords: DNA density, melting curves, micronuclear DNA, polytene chromosomes

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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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