Direct Binding of SAS-6 to ZYG-1 Recruits SAS-6 to the Mother Centriole for Cartwheel Assembly

• Published in: Developmental cell 2013-05, Vol.25 (3), p.284-298
• Main Authors: Lettman, Molly M., Wong, Yao Liang, Viscardi, Valeria, Niessen, Sherry, Chen, Sheng-hong, Shiau, Andrew K., Zhou, Huilin, Desai, Arshad, Oegema, Karen
• Format: Article
• Language: English
• Subjects: Amino Acid Sequence; Animals; Animals, Genetically Modified - embryology; Animals, Genetically Modified - genetics; Animals, Genetically Modified - metabolism; Caenorhabditis elegans - embryology; Caenorhabditis elegans - genetics; Caenorhabditis elegans - metabolism; Caenorhabditis elegans Proteins - genetics; Caenorhabditis elegans Proteins - metabolism; Cell Cycle Proteins - genetics; Cell Cycle Proteins - metabolism; Centrioles - genetics; Centrioles - metabolism; Conserved Sequence; Embryo, Nonmammalian - metabolism; Enzyme Activation; Male; Molecular Sequence Data; Multiprotein Complexes - genetics; Multiprotein Complexes - metabolism; Mutation; Phosphorylation; Protein Binding; Protein Interaction Mapping; Protein Kinases - genetics; Protein Kinases - metabolism; Protein Multimerization; RNA Interference; Transgenes
• ISSN: 1534-5807; 1878-1551
• DOI: 10.1016/j.devcel.2013.03.011

Assembly of SAS-6 dimers to form the centriolar cartwheel requires the ZYG-1/Plk4 kinase. Here, we show that ZYG-1 recruits SAS-6 to the mother centriole independently of its kinase activity; kinase activity is subsequently required for cartwheel assembly. We identify a direct interaction between ZYG-1 and the SAS-6 coiled coil that explains its kinase activity-independent function in SAS-6 recruitment. Perturbing this interaction, or the interaction between an adjacent segment of the SAS-6 coiled coil and SAS-5, prevented SAS-6 recruitment and cartwheel assembly. SAS-6 mutants with alanine substitutions in a previously described ZYG-1 target site or in 37 other residues, either phosphorylated by ZYG-1 in vitro or conserved in closely related nematodes, all supported cartwheel assembly. We propose that ZYG-1 binding to the SAS-6 coiled coil recruits the SAS-6-SAS-5 complex to the mother centriole, where a ZYG-1 kinase activity-dependent step, whose target is unlikely to be SAS-6, triggers cartwheel assembly. [Display omitted] •SAS-6 recruitment to the mother centriole and cartwheel assembly are separable events•Direct binding of ZYG-1 to the SAS-6 coiled coil recruits SAS-6 to the assembly site•ZYG-1 kinase activity is required for cartwheel assembly but not SAS-6 recruitment•SAS-6 is unlikely to be a critical ZYG-1 kinase substrate during cartwheel assembly The Plk4/ZYG-1 kinase controls SAS-6 assembly to form the centriolar cartwheel. Lettman et al. show that SAS-6 recruitment and polymerization are separable steps. ZYG-1 binding to the SAS-6 coiled coil recruits SAS-6 to the assembly site, where a kinase activity-dependent step, whose target is unlikely to be SAS-6, triggers SAS-6 polymerization.