GFP-FLN and GFP-αA differentially localize in cells chemotaxing to cAMP and folate. GFP-FLN loses anterior cortical localization during chemotaxis. (A, B) Vegetative cells expressing GFP-FLN were plated in starvation buffer and imaged after they became polarized in response to the cAMP signal generated as a result of starvation. Cells were imaged as they chemotaxed in the cAMP gradient during early development. Anterior cortical localization of GFP-FLN is also lost (arrow) in cells undergoing folate chemotaxis (C). The same results were obtained in cells expressing the GFP-FLNABD probe (D-F). Both GFP-αA and GFP-αAABD maintain localization at the leading edge of a polarized cells during chemotaxis to cAMP and folate (G-L). Cells expressing GFP alone show no localization of the probe during chemotaxis (M-O).