Figure 3.

Dynein structure and arrangement in the whole axoneme. (A) Dynein arrangement in the PEA region. Surface rendering of averaged map of MTD2-9 shows that dyneins b and f (black arrows) are missing. WT, wild type. (B) Comparison between the proximal and distal regions in the MTD groups 1, 2–8, and 9. Minus (−) and plus (+) signs denote the proximal and central/distal regions, respectively. The black arrows indicate the missing dynein b in MTD2-8−, MTD9−, and MTD9+. The orange arrowhead indicates the position of the 1–2 bridge between MTD1− and MTD2−. The blue arrow points to the bulb density that differs between MTD1− and MTD1+ (referred to as MD2 in Fig. 4). Structures shown in orange are the 1–2 bridges, and those in dark green are IDL3, an interdoublet linker between MTD1 and 2 (Bui et al., 2009). (C) View of the section cut perpendicular to the 1–2 bridge of MTD1+ and MTD1−. The black arrowhead shows the dynein f IC/LC in MTD1+, which is missing in MTD1−. (D) Close-up views of a region proximal to RS1 (black frame in B) of MTD1− (left), MTD1+ (middle), and the overlapped image (right). The blue mesh in the right image represents the IDA density of MTD1+ corresponding to the region in red in the middle image. The blue arrowheads point to the tails of MD2 and dynein a. The white arrowheads indicate the bulb density on the A-tubule that is in contact with dynein fα and MD2. Bars, 16 nm.