First published online December 20, 2007
Journal of Cell Science 121, 102e (2008)
© The Company of Biologists Limited
Chemotaxis: best foot forward
When food is scarce, the unicellular slime mould Dictyostelium aggregates into a large multicellular fruiting body. Waves of extracellular cAMP direct this aggregation by promoting chemotactic cell movement as well as cell-cell contacts (cell streaming). Cells lacking cGMP are known to form aberrant lateral pseudopodia, but the effects of this on cell movement are unclear. Now Douwe Veltman and Peter van Haastert (p. 120) demonstrate that cGMP is required for normal chemotaxis and cell streaming. Using a strain that lacks guanylate cyclase activity, they show that individual mutant cells move as rapidly as wild-type cells upon exposure to cAMP but are unable to maintain their orientation between waves of cAMP. Consequently, their chemotactic movement follows a less efficient path. Additionally, mutant cells form smaller, destabilised streams and, ultimately, smaller fruiting bodies. The authors conclude that the formation of pseudopodia at the rear of cGMP-deficient cells impedes both directional sensing and cell-cell contact, demonstrating that efficient chemotaxis requires an inactive cell posterior.
Related articles in JCS:
- The role of cGMP and the rear of the cell in Dictyostelium chemotaxis and cell streaming
- Douwe M. Veltman and Peter J. M. van Haastert
JCS 2008 121: 120-127.
[Abstract]
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