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Centrosome Aurora A gradient ensures single polarity axis in C. elegans embryos
Sukriti Kapoor1, Sachin Kotak1
1Department of Microbiology and Cell Biology (MCB), Indian Institute of Science (IISc), 560012 Bangalore, India.
Biochemical Society Transactions
|June 30, 2020
Summary
Aurora A kinase is crucial for establishing a single body axis in C. elegans embryos by regulating actomyosin contractility. Its role in symmetry breaking is independent of centrosome maturation, revealing a novel function in early development.
Area of Science:
- Developmental Biology
- Cell Biology
- Genetics
Background:
- Cellular asymmetries drive cell fate diversity in development and stem cells.
- Centrosomes initiate polarity and anterior-posterior axis formation in the Caenorhabditis elegans embryo.
- Polarity establishment involves centrosome signaling to the cell cortex, disassembling the actomyosin network and breaking symmetry.
Purpose of the Study:
- To identify the unknown component at centrosomes that promotes symmetry breaking.
- To investigate the role of Aurora A kinase in polarity establishment.
- To elucidate the mechanism of centrosome-dependent symmetry breaking.
Main Methods:
- Investigated the function of Aurora A kinase (AIR-1) in one-cell C. elegans embryos.
- Observed the effects of Aurora A loss on actomyosin-based cortical flows.
- Analyzed the impact on polarity axis formation and symmetry breaking.
Main Results:
- Loss of Aurora A disrupts actomyosin cortical flows essential for polarity establishment.
- Aurora A deficiency leads to the formation of multiple polarity axes.
- Aurora A's role in ensuring a single polarity axis is independent of its centrosome maturation function.
Conclusions:
- Aurora A kinase plays an unconventional role in symmetry breaking during early embryonic development.
- Aurora A likely regulates symmetry breaking through direct control of Rho-dependent contractility.
- A refined model of centrosome-dependent symmetry breaking involving Aurora A is proposed.
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