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Updated: Jul 27, 2025
09:40
Whole Retinal Explants from Chicken Embryos for Electroporation and Chemical Reagent Treatments
Published on: September 30, 2015
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RNA SYNTHESIS IN THE DIFFERENT PHASES OF CELL CYCLE OF CHICK EMBRYO CELLS
1Biology Division, National Cancer Center Research Institute, Tsukiji, Chuo-ku, Tokyo.
Development, Growth & Differentiation
|June 7, 2023
Summary
RNA synthesis in chick embryo fibroblasts increases significantly after cell cycle synchronization. Ribosomal RNA synthesis is specifically inhibited by actinomycin D, affecting precursor RNA incorporation.
Area of Science:
- Cell Biology
- Molecular Biology
- Biochemistry
Background:
- Understanding RNA synthesis dynamics is crucial for cell cycle regulation.
- Chick embryo fibroblasts provide a model system for studying cellular processes.
Purpose of the Study:
- To investigate RNA synthesis patterns during different cell cycle phases.
- To analyze the impact of synchronization on RNA production.
- To determine the effect of actinomycin D on specific RNA types.
Main Methods:
- Synchronization of chick embryo fibroblasts using medium replacement.
- Measurement of radioactive RNA incorporation over time.
- Analysis of RNA sedimentation patterns and base composition.
- Treatment with actinomycin D to assess ribosomal RNA synthesis.
Main Results:
- RNA synthesis increased substantially with time post-synchronization.
- Radioactive incorporation into nuclear RNA showed a significant rise.
- Newly synthesized RNA exhibited variations in base composition, even within the G1 phase.
- Actinomycin D specifically inhibited ribosomal RNA synthesis.
Conclusions:
- Cell cycle progression significantly influences RNA synthesis rates.
- Ribosomal precursor RNA is a major site of incorporation.
- Variations in RNA base composition occur during the cell cycle.
- Actinomycin D offers a specific method to inhibit ribosomal RNA synthesis.
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