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Updated: Jul 27, 2025
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Production of Xenopus tropicalis Egg Extracts to Identify Microtubule-associated RNAs
Published on: June 27, 2013
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INITIATION OF RIBOSOMAL RNA SYNTHESIS AND CELL DIVISION IN XENOPUS LAEVIS EMBRYOS.
Y Misumi1, S Kurata1, K Yamana1
1Department of Biology, Faculty of Science, Kyushu University 33, Fukuoka, 812 Japan.
Development, Growth & Differentiation
|June 7, 2023
Summary
In Xenopus embryos, isolated animal and vegetal cells maintain their division timing. Ribosomal RNA (rRNA) synthesis initiates after the 15th cell division, suggesting cell division influences rRNA synthesis timing.
Area of Science:
- Developmental Biology
- Cell Biology
- Molecular Biology
Background:
- Early embryonic development in Xenopus involves precise cell division and gene expression timing.
- Understanding the regulation of ribosomal RNA (rRNA) synthesis is crucial for cell growth and differentiation.
Purpose of the Study:
- To determine the temporal relationship between cell division and rRNA synthesis in isolated Xenopus blastula cells.
- To investigate potential differences in rRNA content and concentration between animal and vegetal pole cells.
Main Methods:
- Isolation and culture of animal and vegetal pole cells from Xenopus blastulae.
- Measurement of rRNA synthesis via (3H)methionine incorporation.
- Assessment of cell division by monitoring cell size and rRNA content.
- Examination of nucleoli morphology.
Main Results:
- Isolated Xenopus animal and vegetal cells divided with a temporal pattern similar to intraembryonic cells.
- rRNA synthesis commenced shortly after the presumed 15th cell division post-fertilization.
- Significant differences in rRNA content and concentration were observed between animal and vegetal cells at this stage.
Conclusions:
- Cell division appears to play a role in regulating the timing of rRNA synthesis during early Xenopus development.
- Distinct rRNA levels in animal and vegetal cells suggest regional differences established early in development.
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