Fig. 2. ChlR1 localizes to chromatin, spindle poles and the midbody. Confocal images of ChlR1 localization in RPE-1 cells at different stages of mitosis. (A) ChlR1 was detected using antibody 2075 (green), -tubulin was stained red and DNA stained blue; merged images are shown on the right. Bar, 8 µm. Spindle poles and midbody structures are indicated by arrows in prophase and telophase, respectively. (B) Top panels: RPE1 cells were transfected with 20 nM ChlR1-specific siRNA and stained for ChlR1 protein (green) and DNA (blue). Image shown is a cell at metaphase with no detectable ChlR1-specific staining at the spindles poles. Bottom panels: ChlR1 2075 antibody was incubated with 50 µg/ml ChlR1 peptide (used to raise antibody) for 15 minutes at room temperature and then used to detect ChlR1 in RPE1 cells. Incubation of ChlR1 antiserum with peptide significantly reduced specific fluorescence (a telophase cell is shown).