An amplified genome that may have resulted from recombination within bidirectionally replicating DNA

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Updated: Oct 20, 2026

Recombineering Homologous Recombination Constructs in Drosophila
14:23

Recombineering Homologous Recombination Constructs in Drosophila

Published on: July 13, 2013

D Gendron, L Delbecchi, P Bourgaux

    Gene
    |January 1, 1986
    PubMed

    Insights

    Shifting permissive mouse cells with a temperature-sensitive polyomavirus (Py) genome induced viral DNA accumulation. An unusual recombination product between replicating Py-mouse DNA molecules was observed, potentially explaining gene amplification in mammalian cells.

    Area of Science:

    • Molecular Biology
    • Virology
    • Genetics

    Background:

    • Temperature-sensitive (ts) polyomavirus (Py) genomes in permissive mouse cells can lead to viral DNA accumulation upon temperature downshifts.
    • Understanding the mechanisms of viral DNA replication and host-cell interactions is crucial.

    Purpose of the Study:

    • To investigate the nature of products generated during the induction of viral DNA accumulation.
    • To explore the potential relevance of observed phenomena to gene amplification mechanisms in mammalian cells.

    Main Methods:

    • Induction of viral DNA accumulation by temperature shift-down in ts Py-transformed mouse cells.
    • Analysis of the structure of viral DNA products using molecular techniques.

    Main Results:

    • Temperature shift-down induced the accumulation of free copies of the viral DNA.
    • An unusual recombination product was identified, consistent with recombination between bidirectional replication forks of Py-mouse DNA molecules.

    Conclusions:

    • The observed recombination event provides a potential model for understanding gene amplification in mammalian systems.
    • This finding highlights the complex interplay between viral replication and host cell DNA metabolism.

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