Phototaxis is partially restored in bbs4-1 during flagellar regeneration. Dish phototaxis assays of wild type (g1) and bbs4-1 during flagellar regeneration. Cells were deflagellated by pH shock and allowed to regenerate flagella. Samples were transferred to culture dishes and exposed to directional light (direction indicated by arrows) for ∼10 min. T43, T52, T69, and T120 refer to the time in minutes since deflagellation. Controls were treated identically except that the pH shock was omitted.