Actomyosin-based self-organization of cell internalization during C. elegans gastrulation
Christian Pohl1, Michael Tiongson, Julia L Moore
1Developmental Biology Program, Sloan-Kettering Institute, 1275 York Avenue, New York, NY 10065, USA.
BMC Biology
|December 4, 2012
Summary
This study reveals a new self-organizing mechanism in Caenorhabditis elegans gastrulation, where cells internalize via rosettes. This process demonstrates robustness and adaptability in embryogenesis.
Area of Science:
- Developmental Biology
- Cellular Biology
- Morphogenesis
Background:
- Gastrulation is a critical embryonic process requiring robust and adaptable cellular coordination.
- Mechanisms of self-organization, where global order arises from local interactions, remain poorly understood in gastrulation.
Purpose of the Study:
- To elucidate the self-organizing mechanisms underlying cell internalization during Caenorhabditis elegans gastrulation.
- To investigate the adaptability and scalability of these self-organizing processes.
Main Methods:
- Observation of cell internalization dynamics during C. elegans gastrulation.
- Analysis of cellular behaviors including apical contractile flows and centripetal extensions.
- Investigation of actomyosin-based patterning and monolayer remodeling.
Main Results:
- Identified a modular structure of cell internalization forming rosettes.
- Demonstrated a novel mode of monolayer remodeling without an actin purse-string.
- Showcased the system's adaptability to topological alterations and scalability of actomyosin-based patterning.
- Observed surface cell layer spreading via coplanar division, resembling epiboly.
Conclusions:
- C. elegans gastrulation employs a system-level solution combining coplanar division-based spreading and local internalization modules for volume rearrangement.
- The observed gastrulation mode aligns with general monolayer remodeling principles and actomyosin-based morphogenesis.
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