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Identification of adenovirus genes that require template replication for expression

L D Crossland, H J Raskas

    Journal of Virology
    |June 1, 1983
    PubMed

    Insights

    Adenovirus type 2 DNA replication is essential for the expression of intermediate viral genes like proteins IX and IVa2. Viral DNA replication must occur before transcription of these genes can begin.

    Area of Science:

    • Molecular Virology
    • Viral Gene Expression
    • Adenovirus Research

    Background:

    • Adenovirus type 2 intermediate-stage viral genes are expressed after initial infection.
    • The precise regulation of these genes in relation to viral DNA replication is not fully understood.

    Purpose of the Study:

    • To investigate the relationship between adenovirus type 2 DNA replication and the expression of intermediate-stage viral genes.
    • To determine the regulatory mechanisms controlling the transcription of proteins IX and IVa2.

    Main Methods:

    • Utilized hydroxyurea to inhibit viral DNA replication.
    • Employed pulse-labeling experiments to assess gene transcription.
    • Conducted superinfection experiments to evaluate viral and cellular factor contributions.

    Main Results:

    • Inhibition of DNA replication prevented IX and IVa2 mRNA expression, but not E1b mRNA.
    • The block in IX and IVa2 expression occurred at the transcriptional level.
    • Viral DNA replication is a prerequisite for IX gene transcription.

    Conclusions:

    • Adenovirus type 2 DNA replication is a critical regulatory step for the expression of intermediate viral genes.
    • Late-stage viral and cellular factors alone are insufficient to activate IX gene expression without prior DNA replication.

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