Here, we found that CCDC114 and ARMC4 are undetectable in the ciliary axonemes of CCDC151 mutant individuals, indicating that their ciliary localization is CCDC151 dependent. Moreover, we demonstrate that CCDC151 and CCDC114 interact together by coimmunoprecipitation analyses. Fundamental to the process of assembly and attachment of the dynein arms into axonemes is the correct targeting and docking of the ODAs via the ODA docking complex (ODA-DC) system, and human CCDC114 and ARMC4 have been implicated as integral or associated ODA-DC proteins, representing essential components for attachment of ODAs into ciliary axonemes. Furthermore, mutations in ARMC4 and CCDC114 cause PCD with outer dynein arm defects similarly to the CCDC151 mutations reported here.15,16,21,60,61 CCDC114 is the vertebrate ortholog of the Chlamydomonas ODA-DC component DC2.15,16 Chlamydomonas has two other ODA-DC proteins, the coiled-coil DC1 and the EF-hand DC3/DLE3,62,63 which still have no defined vertebrate orthologs. The armadillo-repeat ARMC4 has been shown to be CCDC114 dependent for its localization into axonemes and to be involved in the correct targeting and docking of the ODAs.21 These data therefore suggest that CCDC151 is required for assembly of ODAs as well as ODA-DCs into axonemes.