TBP and spinocerebellar ataxia type 17: To examine whether these fragments are also detectable in our SCA17 models, we performed western blot analysis of protein homogenates extracted from HEK 293T cells transfected with myc-tagged full-length human TBP (myc-TBP) with 38Q or 64Q and from the cerebellum of our TBPQ64 rats.