Fig. 2. Immunofluorescence localization of Rab4 in cultured rat hepatocytes. Overnight cultured rat hepatocytes grown on collagen-coated glass coverslips were incubated with Texas-Red-labeled ASOR for 20 minutes, treated with streptolysin O to permeabilize the plasma membrane, and stained with anti-Rab4 monoclonal antibody and Cy2-labeled anti-mouse antibody. Merged images of confocal sections and corresponding phase images of two representative cells are presented, revealing punctate areas of overlap (arrows) between endocytosed ASOR (red) and Rab4 (green). Bar, 10 µm.