Extended Data Fig. 3: Structure of the C. reinhardtii tether/tetherhead (T/TH) complex.
From: Axonemal structures reveal mechanoregulatory and disease mechanisms
a, Composite cryo-EM map colored by T/TH subunit and the motor domains of inner dynein arm (IDA) fα and fβ. The doublet microtubule surface is shown in gray. The N-terminal pair of β-propellers of FAP44 interact with the AAA1, AAA6, and C-terminal domains of the fα motor. b, Domain organization of T/TH subunits FAP43, FAP44, and MOT7. Both FAP43 and FAP44 contain an N-terminal pair of β-propellers, followed by a helical stellate structure, and a microtubule-associated coiled coil (CC). MOT7 contains a BLUF domain that is proposed to sense blue light12. c, Schematic illustrating the six-armed stellate structure of T/TH with MOT7 at the center. d, Reverse side of the stellate showing the position of MOT7 and its BLUF domain (bright red) within the cryo-EM map. The resolution is too low to observe any flavin cofactors. On the left, the N-terminal pair of β-propellers from FAP43 bind arm 2 of the stellate. e, Interaction of the FAP43/44 coiled coil with the inner junction proteins FAP20 and PACRG. Bulky sidechain residues used for identification are labeled.
