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MicroRNA-based Regulation of Picornavirus Tropism
09:05

MicroRNA-based Regulation of Picornavirus Tropism

Published on: February 6, 2017

INTRACELLULAR FATE OF MENGO VIRUS RIBONUCLEIC ACID

M HOMMA, A F GRAHAM

    Journal of Bacteriology
    |January 1, 1965
    PubMed

    Insights

    Mengo virus ribonucleic acid (RNA) remained intact and infectious within host cells during the early infection phase. Only a fraction of adsorbed virus particles successfully delivered their RNA for replication, suggesting a selective uncoating process.

    Area of Science:

    • Virology
    • Molecular Biology
    • Cell Biology

    Background:

    • Mengo virus infection involves the entry of viral ribonucleic acid (RNA) into host cells.
    • Understanding the intracellular fate of viral RNA is crucial for comprehending viral replication cycles.
    • The early stages of viral infection, including the eclipse period, are critical for establishing infection.

    Purpose of the Study:

    • To investigate the intracellular fate and biological activity of Mengo virus RNA after adsorption to host cells.
    • To determine if parental viral RNA remains intact and functional during the early stages of infection.
    • To explore the uncoating process and the role of parental RNA in Mengo virus infection.

    Main Methods:

    • Labeling purified Mengo virus with P(32) for tracking.
    • Adsorption of labeled virus to L cells in suspension culture.
    • Extraction of total cellular RNA using a phenol technique at various time points.
    • Infectivity titrations to assess RNA biological activity.
    • Sucrose gradient sedimentation to analyze RNA structural integrity.
    • Ribonuclease digestion assays to evaluate RNA degradation.
    • Electron microscopy to assess viral particle infectivity.

    Main Results:

    • P(32)-labeled Mengo virus adsorbed rapidly and irreversibly to L cells.
    • Extracted RNA retained full biological activity and structural integrity throughout the early eclipse period.
    • No evidence of a double-stranded structure involving parental RNA was found.
    • Less than 20% of parental RNA was susceptible to ribonuclease digestion within 7 hours post-infection.
    • Electron microscopy revealed only 20% of purified viral particles were infectious.
    • A maximum of 4.5% of parental RNA was transferred to progeny virus.

    Conclusions:

    • Mengo virus RNA remains undegraded and biologically active within the host cell during the early eclipse period.
    • A significant portion of adsorbed virus particles may not undergo uncoating, with only a fraction delivering functional RNA.
    • The findings suggest a selective uncoating mechanism, where only infectious viral particles contribute their RNA to the infection process.
    Keywords:
    CARBON ISOTOPESCENTRIFUGATIONENCEPHALOMYOCARDITIS VIRUSESEXPERIMENTAL LAB STUDYL CELLSMETABOLISMMICROSCOPY, ELECTRONPHOSPHORUS ISOTOPESRIBONUCLEASERNA, VIRALTISSUE CULTURE

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