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Updated: Jun 5, 2026
04:17
Nuclear Migration in the Drosophila Oocyte
Published on: May 13, 2021
Nucleolar Dynamics During Oogenesis
Ruoyu Li1, Grace McKown1, Dai Tsuchiya1
1Stowers Institute for Medical Research.
Biorxiv : the Preprint Server for Biology
|June 4, 2026
Summary
Nucleoli dynamically reorganize during zebrafish oogenesis, forming around extrachromosomal DNA. This remodeling of nucleolar condensates is conserved in mouse oocytes, adapting to increased translational demands.
Area of Science:
- Cell Biology
- Developmental Biology
- Molecular Biology
Background:
- Ribosome biogenesis is a crucial, regulated process initiated in the nucleolus.
- Nucleolar organization is known to change under stress, but its modulation during normal development is unclear.
- Oogenesis requires a significant increase in protein synthesis, necessitating changes in ribosome production.
Purpose of the Study:
- To investigate the regulation of nucleolar architecture during zebrafish oogenesis.
- To understand how nucleolar organization adapts to meet increasing translational demands during development.
- To explore the role of extrachromosomal DNA in nucleolus formation.
Main Methods:
- Live imaging of zebrafish oocytes.
- High-resolution microscopy to observe nucleolar structure and dynamics.
- Analysis of nucleolar number, size, localization, and layering.
- Investigation of the association between nucleoli and extrachromosomal DNA.
Main Results:
- Nucleoli exhibit coordinated changes in number, size, subnuclear localization, and layering during oogenesis.
- Nucleoli form around extrachromosomal DNA circles containing the ribosomal DNA (rDNA) locus.
- Similar developmental changes in nucleolar layering and phase organization are observed in mouse oocytes.
- Nucleolar remodeling represents a conserved adaptation to developmental needs.
Conclusions:
- Nucleolar architecture is dynamically regulated during oogenesis to support massive protein synthesis.
- Extrachromosomal DNA plays a role in the formation and organization of nucleoli.
- The remodeling of nucleolar condensates is a conserved mechanism across species during oogenesis.
- These findings reveal novel regulatory mechanisms of nucleolar organization in response to physiological demands.
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