Distinct cell shapes determine accurate chemotaxis

TL;DR

This study reveals that amoeboid cells utilize distinct shapes and movement modes depending on chemical gradient strength, which are intrinsically linked to their sensing accuracy, suggesting conserved strategies across cell types.

Contribution

The paper identifies a limited set of shape modes in amoebae that correlate with chemotactic accuracy and demonstrates their dependence on gradient conditions, linking cell shape to sensing limits.

Findings

Cells adopt specific shape modes depending on gradient strength.

Distinct shapes are associated with accurate chemotaxis.

Behaviours are conserved across different cell types.

Abstract

The behaviour of an organism often reflects a strategy for coping with its environment. Such behaviour in higher organisms can often be reduced to a few stereotyped modes of movement due to physiological limitations, but finding such modes in amoeboid cells is more difficult as they lack these constraints. Here, we examine cell shape and movement in starved Dictyostelium amoebae during migration toward a chemoattractant in a microfluidic chamber. We show that the incredible variety in amoeboid shape across a population can be reduced to a few modes of variation. Interestingly, cells use distinct modes depending on the applied chemical gradient, with specific cell shapes associated with shallow, difficult-to-sense gradients. Modelling and drug treatment reveals that these behaviours are intrinsically linked with accurate sensing at the physical limit. Since similar behaviours are observed in a diverse range of cell types, we propose that cell shape and behaviour are conserved traits.