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Generation of Aggregates of Mouse Embryonic Stem Cells that Show Symmetry Breaking, Polarization and Emergent Collective Behaviour In Vitro
Published on: November 24, 2015
Generating asymmetry: with and without self-renewal.
Ivana Gaziova1, Krishna Moorthi Bhat
1Department of Neuroscience and Cell Biology, University of Texas Medical Branch School of Medicine, Galveston, Texas 77555, USA.
Progress in Molecular and Subcellular Biology
|June 26, 2007
Summary
Asymmetric cell division allows cells to generate diverse progeny or self-renew. This review explores genetic regulation of self-renewing versus non-self-renewing asymmetric divisions in the Drosophila central nervous system.
Area of Science:
- Developmental Biology
- Cell Biology
- Neuroscience
Background:
- Asymmetric cell division is a fundamental process in organismal evolution, enabling cell diversification and renewal.
- This division type underlies the function of stem cells and organismal development.
- The evolutionary order of self-renewing versus non-self-renewing asymmetric division remains unclear.
Purpose of the Study:
- To explore the genetic regulation of self-renewing and non-self-renewing asymmetric cell divisions.
- To utilize the Drosophila central nervous system (CNS) as a model system for this investigation.
- To provide insights into stem cell regulation conserved across species.
Main Methods:
- Review of recent studies on genetic regulation of asymmetric cell division.
- Analysis of gene expression patterns (up-regulation of stem cell proteins, down-regulation of differentiation proteins).
- Investigation of asymmetric segregation of proteins and cell identity factors.
Main Results:
- Self-renewing asymmetric division requires maintaining/up-regulating "stem cell" proteins and repressing differentiation genes.
- Non-self-renewing asymmetric division involves down-regulating stem cell proteins and asymmetric segregation of identity factors.
- Mutational analyses have elucidated the molecular basis of these divisions.
Conclusions:
- A balance of stem cell and differentiation factors, achieved through asymmetric segregation, is crucial for regulated cell division.
- Studies in Drosophila offer insights into conserved mechanisms of stem cell regulation in vertebrates, including humans.
- Understanding asymmetric division is key to comprehending developmental evolution and stem cell biology.
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