Chemotaxis

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	Chemoattractant receptors in chemotaxis Confocal image of GFP-tagged chemoattractant receptors in living amoebae undergoing chemotaxis. The chemoattractant gradient is established using a micropipet located just below the frame. Images were captured every 15 seconds. From Z. Xiao and P.N. Devreotes,  Johns Hopkins Medical Institutions.
	G-protein b-subunits in chemotaxis Confocal image of GFP-tagged Gb-subunits in living amoebae undergoing chemotaxis. The chemoattractant gradient is established using a micropipet located just above the frames. Images were captured every 20 seconds. From T. Jin, N. Zhang, and P.N. Devreotes, Johns Hopkins Medical Institutions.
	PH-domain translocation with uniform stimulus Kinetic analysis of the translocation from the cytoplasm to the plasma membrane of GFP-tagged CRAC (Cytosolic Regulator of Adenylyl Cyclase-a PH domain containing protein) in response to a uniform increase in chemoattractant concentration. Frames were taken every 2 seconds. The chemoattractant was added just before the cell goes out of focus. From C.A. Parent and P.N. Devreotes,  Johns Hopkins Medical Institutions.
	PH-domain translocation during chemotaxis Confocal image of GFP-tagged CRAC in living amoebae undergoing chemotaxis. CRAC-GFP specifically translocates to the leading edge of newly elicited pseudopods. The chemoattractant gradient is established using a micropipet located near the upper right corner of the frame. Images were captured every 5 seconds. From C.A. Parent and P.N. Devreotes, Johns Hopkins Medical Institutions.
	PH-domain translocation in immobilized cells Translocation of CRAC-GFP in cells lacking actin filament formation. Cells chemotaxing towards the micropipet in the lower portion of the frame were treated with Latrunculin A and observed within the next few minutes. Images were captured every 5 seconds. From C.A. Parent and P.N. Devreotes, Johns Hopkins Medical Institutions.
	PH-domain dynamics in immobilized cells Immobilized CRAC-GFP expressing cells can respond to changes in chemoattractant gradients. Latrunculin A treated cells were subjected to changing gradients of chemoattractants by moving the micropipet around the cell. Images were captured every 5 seconds. From C.A. Parent and P.N. Devreotes, Johns Hopkins Medical Institutions.
	Digitized wild-type cell in chemotaxis Three dimensional direct image reconstruction of a D. discoideum amoebae crawling in a gradient of cAMP. The chemoattractant source is left of the field. From D. Wessel and D. Soll, Univ. of Iowa
	Digitized clathrin heavy chain null cell in chemotaxis  Three dimensional direct image reconstruction of a clathrin heavy chain null Dictyostelium cell. Note the aberrant cell shape, lack of polarity and numerous fragmented pseudopods. From D. Wessel and D. Soll, Univ. of Iowa.