The antibodies used are listed in Supplemental Table S2. For generation of an antibody to the IFT46 C-terminus, PCR primer pair IFT46-29 and IFT46-14 was used to amplify a 0.7-kb sequence encoding IFT46 aa 105–344 from a cloned IFT46 cDNA (Hou et al., 2007 (link)). The PCR product was digested with BamHI and inserted into the BamHI site of pMAL-cR1 (New England Biolabs, Beverly, MA). Expression of this construct in Escherichia coli produced a protein in which IFT46 aa 105–344 were fused to maltose-binding protein. The fusion protein was purified by amylase affinity chromatography, and antibodies were raised against the fusion protein in guinea pigs (Covance Research Products, Denver, PA).