To establish the molecular basis for CEP215 function in centrosome-spindle pole attachment, we employed an unbiased proteomic approach to isolat e and identify CEP215 interactors. To this end, affinity purification tags ( Gs TAP containing protein G and streptavidin-binding protein) were inserted in-frame into both alleles of the CEP215 gene (CEP215-TAP cell line) in the chicken B cell line, DT40. Following affinity purification, protein complexes were analysed by mass spectr ometry