Fig 2: SDCCAG8 associates with a characteristic set of proteins at the centrosome.(A) The Sdccag8 interacting proteins discovered by SILAC as centrosomal components belong to 4 functional groups, i.e. centriolar satellite components, endosomal vesicle components, tRNA synthesis complex proteins, and myosin type II motors involved in ciliogenesis. (B) Overview of the SDCCAG8 constructs used in this study. Numbering corresponds to amino acid positions. Gray boxes designate coiled-coil domains. (C) SDCCAG8 interacts with RABEP2, ERC1, and CEP131. FLAG-tagged full-length and truncation constructs of SDCCAG8 were immunoprecipitated from extracts of HEK293 cells transfected with each construct and analyzed by Western blot. Blots were probed for FLAG, or for endogenous RABEP2, ERC1, and CEP131 respectively. Only full-length FLAG-tagged SDCCAG8, but not truncated SDCCAG8 constructs co-immunoprecipitate RABEP2, ERC1 or CEP131, except for the C-terminal SDCCAG8 fragment that weakly co-immunoprecipitated RABEP2. (D) Western blotting for endogenous proteins in whole cell lysates shows equal loading. (E) CEP131 co-immunoprecipitates FLAG-SDCCAG8. Lysates from cells transfected with FLAG-SDCCAG8 and with non-specific control siRNA or with siCEP131 were subjected to immunoprecipitation using anti-CEP131 antibodies or normal IgG. While anti-CEP131 antibodies co-immunoprecipitated FLAG-SDCCAG8 from control lysates, CEP131 knockdown abolished immunoprecipitation of FLAG-SDCCAG8, demonstrating specificity of the interaction.