title: Direct binding of SAS-6 to ZYG-1 recruits SAS-6 to the mother centriole for cartwheel assembly.
abstract: 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.
authors.affiliation: Department of Cellular and Molecular Medicine, Ludwig Institute for Cancer Research, University of California, San Diego, La Jolla, CA 92093, USA.
authors.forename: Molly M
authors.initials: MM
authors.lastname: Lettman
authors.forename: Yao Liang
authors.initials: YL
authors.lastname: Wong
authors.forename: Valeria
authors.initials: V
authors.lastname: Viscardi
authors.forename: Sherry
authors.initials: S
authors.lastname: Niessen
authors.forename: Sheng-Hong
authors.initials: SH
authors.lastname: Chen
authors.forename: Andrew K
authors.initials: AK
authors.lastname: Shiau
authors.forename: Huilin
authors.initials: H
authors.lastname: Zhou
authors.forename: Arshad
authors.initials: A
authors.lastname: Desai
authors.forename: Karen
authors.initials: K
authors.lastname: Oegema
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D030801:Animals, Genetically Modified / Q000196:embryology / Q000235:genetics / Q000378:metabolism; D017173:Caenorhabditis elegans / Q000196:embryology / Q000235:genetics / Q000378:metabolism*; D029742:Caenorhabditis elegans Proteins / Q000235:genetics / Q000378:metabolism*; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism*; D002502:Centrioles / Q000235:genetics / Q000378:metabolism*; D017124:Conserved Sequence; D004625:Embryo, Nonmammalian / Q000378:metabolism; D004789:Enzyme Activation; D008297:Male; D008969:Molecular Sequence Data; D046912:Multiprotein Complexes / Q000235:genetics / Q000378:metabolism; D009154:Mutation; D010766:Phosphorylation; D011485:Protein Binding; D025941:Protein Interaction Mapping; D011494:Protein Kinases / Q000235:genetics / Q000378:metabolism*; D055503:Protein Multimerization; D034622:RNA Interference; D019076:Transgenes
chemical_list: D029742:Caenorhabditis elegans Proteins; D018797:Cell Cycle Proteins; D046912:Multiprotein Complexes; C497201:SAS-6 protein, C elegans; D011494:Protein Kinases; C429649:zyg-1 protein, C elegans