Figure 7

Cortexillin depletion in phagocytic cups. The external portions of the budded yeast, which are not visible in the fluorescence images, are denoted by circles. The cells are expressing mRFP-LimEΔ for actin or mRFP-ArpC1 for the Arp2/3 complex (upper panels) together with GFP-cortexillin I (lower panels). (a) Three examples of uptake of budded yeast: (left panel) an early stage of uptake, (middle) an intermediate stage, and (right) completed uptake. At all stages, cortexillin I is uniformly depleted from the phagosome membrane, whereas actin and the Arp2/3 complex are enriched around the neck of the particle. (b) Sequence showing severing of a budded yeast with strong accumulation of actin around the neck of the particle. Cortexillin I is depleted from the entire cup at all stages of severing. Numbers indicate time in seconds. Bar = 10 μm for all images.