LAT dramatically alters the diffusion profile of glycoproteins. (A) Cells expressing YE(gly)2 were pretreated with vehicle (N,N-dimethylformamide), 1 μM LAT for 5 min, or 66 μM nocodazole for 60 min. The G(τ) of YE(gly)2 in each condition is shown. The number of measurements was 52 for vehicle, 33 for LAT, and 46 for nocodazole. G(τ) was assumed to be composed of the same components as in Fig. 3, and the best fits to the model are shown. (inset) LAT treatment has little effect on the diffusion of YE. G(τ) was measured in YE-expressing cells treated with vehicle or with LAT for 8 min. Number of measurements = 23. Means with 95% confidence interval are shown. (B) Time lapse of the diffusion profile in a single cell. Diffusion of YE(gly)2 in a single spot of a cell was recorded for a total of 15 min. 1 ml of medium containing 2 μM LAT was added at 7 min, immediately after the second FCS measurement. Images of the cell are shown before and after the treatment. G(τ) was obtained at 0, 5, 11, and 15 min. The best fits are shown. (C) Images of YFP-actin in a single cell before and after the treatment. The numerous filamentous fibers of YFP-actin were diminished after treatment. Bars: (B) 5 μm; (C) 1 μm.
