title: The conserved protein SZY-20 opposes the Plk4-related kinase ZYG-1 to limit centrosome size.
abstract: Microtubules are organized by the centrosome, a dynamic organelle that exhibits changes in both size and number during the cell cycle. Here we show that SZY-20, a putative RNA-binding protein, plays a critical role in limiting centrosome size in C. elegans. SZY-20 localizes in part to centrosomes and in its absence centrosomes possess increased levels of centriolar and pericentriolar components including gamma-tubulin and the centriole duplication factors ZYG-1 and SPD-2. These enlarged centrosomes possess normal centrioles, nucleate more microtubules, and fail to properly direct a number of microtubule-dependent processes. Depletion of ZYG-1 restores normal centrosome size and function to szy-20 mutants, whereas loss of szy-20 suppresses the centrosome duplication defects in both zyg-1 and spd-2 mutants. Our results describe a pathway that determines centrosome size and implicate centriole duplication factors in this process.
authors.affiliation: Laboratory of Biochemistry and Genetics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20894, USA. mihyesong@mail.nih.gov
authors.forename: Mi Hye
authors.initials: MH
authors.lastname: Song
authors.forename: L
authors.initials: L
authors.lastname: Aravind
authors.forename: Thomas
authors.initials: T
authors.lastname: Müller-Reichert
authors.forename: Kevin F
authors.initials: KF
authors.lastname: O'Connell
mesh_terms: D000483:Alleles; D000818:Animals; D017173:Caenorhabditis elegans; D029742:Caenorhabditis elegans Proteins / Q000737:chemistry / Q000378:metabolism / Q000502:physiology*; D002467:Cell Nucleus / Q000378:metabolism; D002502:Centrioles / Q000648:ultrastructure; D018385:Centrosome / Q000648:ultrastructure*; D018507:Gene Expression Regulation, Developmental; D008870:Microtubules / Q000378:metabolism; D008954:Models, Biological; D008957:Models, Genetic; D009154:Mutation; D011494:Protein Kinases / Q000737:chemistry / Q000378:metabolism / Q000502:physiology*; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism*; D016601:RNA-Binding Proteins / Q000378:metabolism / Q000502:physiology*
chemical_list: D029742:Caenorhabditis elegans Proteins; D016601:RNA-Binding Proteins; C534298:SZY-20 protein, C elegans; D011494:Protein Kinases; C429649:zyg-1 protein, C elegans; D017346:Protein Serine-Threonine Kinases