Chemotaxis: a feedback-based computational model robustly predicts multiple aspects of real cell behaviour

Matthew P. Neilson, Douwe M. Veltmahn, Peter J.M. van Haastert, Steven Webb, John A. Mackenzie, Robert H. Insall

Research output: Contribution to journalArticle

89 Citations (Scopus)

Abstract

The mechanism of eukaryotic chemotaxis remains unclear despite intensive study. The most frequently described mechanism acts through attractants causing actin polymerization, in turn leading to pseudopod formation and cell movement. We recently proposed an alternative mechanism, supported by several lines of data, in which pseudopods are made by a self-generated cycle. If chemoattractants are present, they modulate the cycle rather than directly causing actin polymerization. The aim of this work is to test the explanatory and predictive powers of such pseudopod-based models to predict the complex behaviour of cells in chemotaxis. We have now tested the effectiveness of this mechanism using a computational model of cell movement and chemotaxis based on pseudopod autocatalysis. The model reproduces a surprisingly wide range of existing data about cell movement and chemotaxis. It simulates cell polarization and persistence without stimuli and selection of accurate pseudopods when chemoattractant gradients are present. It predicts both bias of pseudopod position in low chemoattractant gradients and—unexpectedly—lateral pseudopod initiation in high gradients. To test the predictive ability of the model, we looked for untested and novel predictions. One prediction from the model is that the angle between successive pseudopods at the front of the cell will increase in proportion to the difference between the cell's direction and the direction of the gradient. We measured the angles between pseudopods in chemotaxing Dictyostelium cells under different conditions and found the results agreed with the model extremely well. Our model and data together suggest that in rapidly moving cells like Dictyostelium and neutrophils an intrinsic pseudopod cycle lies at the heart of cell motility. This implies that the mechanism behind chemotaxis relies on modification of intrinsic pseudopod behaviour, more than generation of new pseudopods or actin polymerization by chemoattractants.

LanguageEnglish
Article numbere1000618
Number of pages11
JournalPLOS Biology
Volume9
Issue number5
DOIs
Publication statusPublished - 17 May 2011

Fingerprint

pseudopodia
Pseudopodia
chemotaxis
Chemotaxis
Feedback
Chemotactic Factors
Cells
chemoattractants
Actins
cells
cell movement
Polymerization
Cell Movement
polymerization
actin
Dictyostelium
Aptitude
Polarization
prediction
attractants

Keywords

  • chemotaxis
  • cells
  • chemotactic molecules
  • pseudopods
  • computational model

Cite this

Neilson, Matthew P. ; Veltmahn, Douwe M. ; van Haastert, Peter J.M. ; Webb, Steven ; Mackenzie, John A. ; Insall, Robert H. / Chemotaxis : a feedback-based computational model robustly predicts multiple aspects of real cell behaviour. In: PLOS Biology. 2011 ; Vol. 9, No. 5.
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Chemotaxis : a feedback-based computational model robustly predicts multiple aspects of real cell behaviour. / Neilson, Matthew P.; Veltmahn, Douwe M.; van Haastert, Peter J.M.; Webb, Steven; Mackenzie, John A.; Insall, Robert H.

In: PLOS Biology, Vol. 9, No. 5, e1000618, 17.05.2011.

Research output: Contribution to journalArticle

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T2 - PLOS Biology

AU - Neilson, Matthew P.

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