Fig. 3. Mammalian Lis1 localizes to motile cilia in isolated airway epithelial cells. Differential interference contrast and corresponding immunofluoresence micrographs of isolated murine tracheal epithelial cells are shown. Except for the two controls at lower right, all micrograph pairs are of cells incubated with a rabbit polyclonal antibody (ab2607) raised against human Lis1. As indicated, the controls were incubated either with no primary antibody or were stained with an irrelevant antibody (against the p24 component of dynactin) to ensure that rabbit immunoglobulin did not bind cilia directly. The prominent structure (white arrow on one panel in top row) underlying the cilia is the layer of basal bodies, which serve as templates for ciliary assembly. Lis1 is present in punctate structures throughout the cytoplasm, shows a strong accumulation in the basal body region and is also clearly present in puncta within cilia. By contrast, no ciliary signal was observed with the dynactin antibody or when the primary antibody was omitted. Bar, 10 µm.