title: CEP120 interacts with CPAP and positively regulates centriole elongation.
abstract: Centriole duplication begins with the formation of a single procentriole next to a preexisting centriole. CPAP (centrosomal protein 4.1-associated protein) was previously reported to participate in centriole elongation. Here, we show that CEP120 is a cell cycle-regulated protein that directly interacts with CPAP and is required for centriole duplication. CEP120 levels increased gradually from early S to G2/M and decreased significantly after mitosis. Forced overexpression of either CEP120 or CPAP not only induced the assembly of overly long centrioles but also produced atypical supernumerary centrioles that grew from these long centrioles. Depletion of CEP120 inhibited CPAP-induced centriole elongation and vice versa, implying that these proteins work together to regulate centriole elongation. Furthermore, CEP120 was found to contain an N-terminal microtubule-binding domain, a C-terminal dimerization domain, and a centriolar localization domain. Overexpression of a microtubule binding-defective CEP120-K76A mutant significantly suppressed the formation of elongated centrioles. Together, our results indicate that CEP120 is a CPAP-interacting protein that positively regulates centriole elongation.
authors.affiliation: Institute of Biomedical Sciences, Academia Sinica, Taipei 11529, Taiwan.
authors.forename: Yi-Nan
authors.initials: YN
authors.lastname: Lin
authors.forename: Chien-Ting
authors.initials: CT
authors.lastname: Wu
authors.forename: Yu-Chih
authors.initials: YC
authors.lastname: Lin
authors.forename: Wen-Bin
authors.initials: WB
authors.lastname: Hsu
authors.forename: Chieh-Ju C
authors.initials: CJ
authors.lastname: Tang
authors.forename: Ching-Wen
authors.initials: CW
authors.lastname: Chang
authors.forename: Tang K
authors.initials: TK
authors.lastname: Tang
mesh_terms: D000595:Amino Acid Sequence; D001345:Autoradiography; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism*; D002502:Centrioles / Q000235:genetics / Q000378:metabolism*; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D057809:HEK293 Cells; D006367:HeLa Cells; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins / Q000235:genetics / Q000378:metabolism; D008869:Microtubule-Associated Proteins / Q000235:genetics / Q000378:metabolism*; D011485:Protein Binding; D025941:Protein Interaction Mapping; D055503:Protein Multimerization; D017434:Protein Structure, Tertiary; D034741:RNA, Small Interfering / Q000235:genetics / Q000378:metabolism; D059807:S Phase Cell Cycle Checkpoints; D014162:Transfection
chemical_list: C414735:CENPJ protein, human; D018797:Cell Cycle Proteins; D047908:Intracellular Signaling Peptides and Proteins; D008869:Microtubule-Associated Proteins; D034741:RNA, Small Interfering; C071236:STIL protein, human; D049452:Green Fluorescent Proteins