Figure 1.

Cells expressing Arf6N48R or N48I or treatment of cells expressing wild-type Arf6 with 1-butanol accumulate tubular endosomes. HeLa cells were transfected with Arf6N48R (A), Arf6N48I (B), or Arf6 (C, D, and F). Some Arf6-expressing cells were incubated with 100 nM cytochalasin D (D), 0.3% 1-butanol (F), or 2-butanol for 30 min. The cells were then fixed and immunolabeled with antibodies to Arf6 and MHCI. The juxtanuclear labeling of MHCI visible in a number of cells represents biosynthetic MHCI in the Golgi complex. Insets show colocalization of MHCI with Arf6. (E) Quantification of cells displaying tubular endosomal phenotype as a percentage of 100 transfected cells counted per experiment. Shown are the mean values with standard deviations from three experiments. Bars, 10 μm.