(A) Isosurface rendering longitudinal images of the axonemes from the WT C. reinhardtii strain (left), mot7 mutant (middle), and the mutant rescued with MOT7-BCCP-3HA (right). The 1α and 1β motor domains of f/I1dynein (58), the tether complex, and the enhanced biotin carboxyl carrier protein (BCCP) tag are indicated in orange, blue, red, and green, respectively. BCCP is associated with both the 1β domain and the tether complex. A part of the tether structure is absent in the mot7 mutant. (B) Tomographic slices of the averaged longitudinal view in axonemes from the WT strain (left), mot7 mutant (middle), and the mutant rescued with MOT7-BCCP-3HA (right). The density of BCCP is clearly seen between f/I1 dynein and the tether complex. The amount of tether complex is significantly decreased in the mot7 mutant, likely due to structural fluctuation. (C) Detailed comparison of isosurface rendering images. The WT strain (left), mot7 mutant (middle), and the mutant rescued with MOT7-BCCP-3HA (right) are shown. Two links between the f/I1 motor domain and the tether complex are colored in dark pink. The link from the tether to the 1β domain is lost in the mot7 mutant, but that from the tether to the 1α domain is retained.