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

Dev Cell. 2013 May 13;25(3):284-98. doi: 10.1016/j.devcel.2013.03.011.

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.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • 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

Substances

  • Caenorhabditis elegans Proteins
  • Cell Cycle Proteins
  • Multiprotein Complexes
  • SAS-6 protein, C elegans
  • Protein Kinases
  • zyg-1 protein, C elegans