Independent control of locomotion and orientation during Dictyostelium discoideum chemotaxis.
Chemotaxis is cell movement in the direction of a chemical and is composed of two component: movement and directionality. The directionality of eukaryotic chemotaxis is probably derived from orientation: the detection of the spacial gradient of chemoattractant over the cell length. Chemotaxis was investigated in eukaryotic Dictyostelium discoideum cells that were permeabilized by high-voltage discharges. These permeable cells respond chemotactically to extracellular cAMP. However, locomotion is impaired if the Ca2+ concentration is clamped at submicromolar concentrations; interestingly, these non-motile cells still form pseudopodia and elongate in the direction of the cAMP gradient. These results imply that locomotion and orientation during Dictyostelium chemotaxis are independently regulated.
Van Duijn
B
B
Cell Biology and Genetics Unit, Leiden University, The Netherlands.
Van Haastert
P J
PJ
D000818:Animals; D002118:Calcium / Q000502:physiology*; D002463:Cell Membrane Permeability; D002633:Chemotaxis; D000242:Cyclic AMP / Q000502:physiology; D004023:Dictyostelium / Q000502:physiology*; D007700:Kinetics
D000242:Cyclic AMP; D002118:Calcium