Extended Data Fig. 9: Conformational changes in inner dynein arm f (IDAf) and the tether/tetherhead (T/TH) complex.
From: Structural diversity of axonemes across mammalian motile cilia
(a) Comparison of our atomic models with subtomogram averages of IDAf in the pre- and post-stroke states, obtained from rapidly frozen live, swimming sea urchin sperm (Lin & Nicastro 2018). (b) Composite map of the motor domains of IDAf (fα and fβ), IDAa, and the T/TH complex (CFAP43, CFAP44, and the sperm-specific TEX47). (c) Cryo-EM density for the motor domains of IDAf (DNAH10 and DNAH2). The linker is colored purple and individual AAA domains are colored from blue to red. (d) Changes in the conformation of the linker and stalk domains of the dynein heavy chains (upper panel: pre-stroke state, lower panel: post-stroke state). (e) Relative orientations of the two motors of IDAf change from perpendicular arrangement in the pre-stroke state (upper panels) to a parallel arrangement in the post-stroke state (lower panels). (f) Conformational changes in the T/TH complex, consisting of CFAP43, CFAP44, and the sperm-specific TEX47. (g) Interaction of the motor domain of fα with CFAP44 and the motor domain of IDAa via CFAP44. The microtubule-binding domain of fα interacts with the N-DRC (arrows). (h) The motor domain of fβ interacts with CFAP43 and IDAd, while its linker interacts with TEX47 and its stalk with IDAg.
