Structural component of ciliary and flagellar microtubules. Plays a key role in the assembly or attachment of the inner dynein arm to microtubules in flagella and cilia. Forms filamentous polymers in the walls of ciliary and flagellar microtubules. Asymmetrically dimethylated at Arg-462 during flagellum resorption. Probably methylated by PRMT1. defects in axonemal inner-arm dynein. Belongs to the tektin family.