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Incomplete divisions between sister germline cells require Usp8 function
Comptes Rendus Biologies
|September 30, 2024
Summary
Cytokinetic abscission, the final step in cell division, is incomplete in germline cells. This study identifies Usp8 as key to blocking abscission, crucial for gamete development and potentially the evolution of multicellularity.
Area of Science:
- Cell Biology
- Developmental Biology
- Evolutionary Biology
Background:
- Cytokinetic abscission typically completes cell division, but germline cells delay this process.
- This incomplete cytokinesis maintains cytoplasmic connections between sister cells, vital for gamete differentiation.
Purpose of the Study:
- To outline molecular events of complete and delayed cytokinesis, focusing on ESCRT-III proteins.
- To reveal molecular mechanisms blocking abscission in Drosophila germline cells.
- To explore the evolutionary significance of incomplete cytokinesis.
Main Methods:
- Review of molecular events in cytokinesis.
- Focus on recent discoveries in Drosophila germline cells.
- Analysis of ESCRT-III protein function and regulation.
Main Results:
- ESCRT-III proteins play a crucial role in both complete and delayed abscission.
- The enzyme Usp8 is vital for incomplete cytokinesis in Drosophila germline cells.
- Usp8 regulates ESCRT-III ubiquitination and localization to block abscission.
Conclusions:
- Incomplete cytokinesis in germline cells is regulated by Usp8.
- Understanding this process may shed light on the origins of multicellularity.
- Further studies in choanoflagellates could elucidate the evolutionary importance of delayed abscission.
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