[Comparison of endogenous nuclear RNA-polymerase II at different stages of mycoplasmodial growth]

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Updated: Aug 15, 2026

Methods to Investigate the Regulatory Role of Small RNAs and Ribosomal Occupancy of Plasmodium falciparum
10:22

Methods to Investigate the Regulatory Role of Small RNAs and Ribosomal Occupancy of Plasmodium falciparum

Published on: December 4, 2015

D A Kostiuchenko, V I Kostiuchenko, G Ia Kolomiĭtseva

    Biokhimiia (Moscow, Russia)
    |September 1, 1982
    PubMed

    Insights

    Investigating Physarum polycephalum nuclei revealed significant differences in RNA synthesis rates between 48- and 96-hour-old microplasmodia. These variations are linked to distinct RNA-polymerase II forms, suggesting a novel regulatory mechanism for transcription.

    Area of Science:

    • Molecular Biology
    • Cell Biology
    • Biochemistry

    Background:

    • Physarum polycephalum is a model organism for studying nuclear processes.
    • Understanding transcriptional regulation is crucial for cell development and function.

    Purpose of the Study:

    • To investigate age-dependent differences in transcription rates in Physarum polycephalum.
    • To identify the molecular mechanisms underlying these transcriptional changes.

    Main Methods:

    • Isolation of nuclei from microplasmodia at different growth stages (48 and 96 hours).
    • Measurement of [3H]UTP incorporation to assess in vitro transcription rates.
    • Analysis of endogenous RNA-polymerase II concentration.
    • Chromatin fragmentation and DEAE-Sephadex chromatography to characterize enzyme forms.

    Main Results:

    • A 7-8 fold difference in [3H]UTP incorporation rates was observed between 48- and 96-hour-old nuclei.
    • A slight (1.6 fold) change in RNA-polymerase II concentration was noted.
    • RNA-polymerase II was resolved into two distinct forms with differing template binding affinities and functional roles.

    Conclusions:

    • Transcription in Physarum polycephalum nuclei is regulated by the interplay of two RNA-polymerase II forms.
    • Age-related changes in the correlation of these enzyme forms likely drive differential transcription rates.

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