KIF1Bα colocalizes with aggregated mitochondria. A, NIH3T3 cells were transfected with anti-sense KBP and costained with MitoTracker (upper picture) and KIF1Bα polylonal antibody (lower picture). Bar, 10 μm. B, 1 μg of KIF1Bα and KIF5B GST-fusion proteins were bound to glutathione Sepharose and incubated with equal aliquots of the same lysate from KBP expressing 293 cells. As a control, GST-Grb2 fusion protein was used. The proteins were separated, transferred to nitrocellulose and immunoblotted with GST-KBP antiserum. Molecular mass markers are shown in kDa, and an arrow indicates the position of KBP. Trf, transfection. C, KBP was transiently overexpressed either alone or together with KIF1Bα-MYC or KIF1Bα350-1135-VSV. Proteins were immunoprecipitated with either VSV or MYC antibody and KBP was detected with the specific antibody. The filter was reprobed with KIF1B antibody, and KBP expression was confirmed as before.