2006 AIChE Annual Meeting
(428h) Role of Phospholipid Signaling in the Gradient Sensing Mechanism of Motile Cells
In general, the spatial segregation of the frontness/backness molecules and the resultant morphological polarization occurs even if the cells are exposed to a uniform chemoattractant profile. This phenomenon has been called spontaneous polarization to emphasize the fact that the cells polarize despite the absence of a perceptible external cue. . The existence of spontaneous polarization is reminiscent of the Turing instability in reaction-diffusion systems. This is exemplified by the so-called activator-inhibitor model, which contains a sluggish activator that is synthesized autocatalytically, and a labile inhibitor that impedes the growth of the activator. I'll present the data showing the existence of an activator in the gradient sensing mechanism of neutrophil-differentiated HL-60 cells. This activator is involved in a positive feedback loop in the phosphoinositide signaling pathways.