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Updated: Jul 3, 2026

The C. elegans Intestine As a Model for Intercellular Lumen Morphogenesis and In Vivo Polarized Membrane Biogenesis at the Single-cell Level: Labeling by Antibody Staining, RNAi Loss-of-function Analysis and Imaging
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The C. elegans Intestine As a Model for Intercellular Lumen Morphogenesis and In Vivo Polarized Membrane Biogenesis at the Single-cell Level: Labeling by Antibody Staining, RNAi Loss-of-function Analysis and Imaging

Published on: October 3, 2017

Modeling the establishment of PAR protein polarity in the one-cell C. elegans embryo

Filipe Tostevin1, Martin Howard

  • 1Department of Mathematics, Imperial College London, London, United Kingdom.

Biophysical Journal
|July 16, 2008
PubMed

Insights

This study models C. elegans embryo polarity establishment, revealing that known PAR protein interactions explain cortical dynamics. Cytoplasmic asymmetry is also critical for proper PAR protein localization in daughter cells.

Area of Science:

  • Cellular Biology
  • Developmental Biology
  • Biophysics

Background:

  • C. elegans embryo polarity is established along the anterior-posterior axis at the one-cell stage.
  • PAR proteins (PAR-3/PAR-6/PKC-3 and PAR-1/PAR-2) form distinct cortical domains driven by cytoskeletal rearrangement after fertilization.
  • Cortical actomyosin contraction is a key event initiating anterior-posterior polarity.

Purpose of the Study:

  • To develop a mathematical model combining PAR protein reaction-diffusion dynamics with actomyosin contraction.
  • To investigate the sufficiency of known PAR protein interactions in explaining observed cortical polarity.
  • To explore additional mechanisms required for proper cytoplasmic PAR protein polarity.

Main Methods:

  • Mathematical modeling integrating reaction-diffusion dynamics of PAR proteins.
  • Coupling PAR protein dynamics with a model of cortical actomyosin contraction.
  • Analysis of both wild-type and mutant C. elegans embryos.

Main Results:

  • The model successfully explains many aspects of cortical PAR protein dynamics using known interactions.
  • Existing models are insufficient to explain cytoplasmic PAR protein polarity.
  • The model predicts that cytoplasmic cytoskeletal asymmetry is crucial for PAR protein localization.

Conclusions:

  • Known PAR protein interactions are sufficient to explain cortical polarity establishment in C. elegans embryos.
  • Cytoplasmic PAR protein polarity requires mechanisms beyond cortical dynamics, specifically cytoskeletal asymmetry.
  • Cytoplasmic and cortical asymmetries together critically determine PAR protein localization during early development.

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