title: Identification of a cell cycle-dependent duplicating complex that assembles basal bodies de novo in Naegleria.
abstract: During the differentiation of the amoeba Naegleria pringsheimi into a flagellate, a transient complex containing γ-tubulin, pericentrin-like protein, and myosin II (GPM complex) is formed, and subsequently a pair of basal bodies is assembled from the complex. It is not understood, however, how a single GPM is formed nor how the capability to form this complex is acquired by individual cells. We hypothesized that the GPM is formed from a precursor complex and developed an antibody that recognizes Naegleria (Ng)-transacylase, a component of the precursor complex. Immunostaining of differentiating cells showed that Ng-transacylase is concentrated at a site in the amoeba and that γ-tubulin is transiently co-concentrated at the site, suggesting that the GPM is formed from a precursor, GPMp, which contains Ng-transacylase and is already present in the amoeba. Immunostaining of growing N. pringsheimi with Ng-transacylase antibody revealed the presence of one GPMp in interphase cells, but two GPMps in mitotic cells, suggesting that N. pringsheimi maintains one GPMp per cell by duplicating and segregating the complex according to its cell cycle. Our results demonstrate the existence of a cell cycle-dependent duplicating complex that provides a site for the de novo assembly of the next generation of basal bodies.
authors.affiliation: Department of Systems Biology, Yonsei University, Seoul 120-749, Korea.
authors.forename: JungHa
authors.initials: J
authors.lastname: Lee
authors.affiliation: Department of Systems Biology, Yonsei University, Seoul 120-749, Korea.
authors.forename: Seungmin
authors.initials: S
authors.lastname: Kang
authors.affiliation: Department of Systems Biology, Yonsei University, Seoul 120-749, Korea.
authors.forename: Yong Seok
authors.initials: YS
authors.lastname: Choi
authors.affiliation: Department of Systems Biology, Yonsei University, Seoul 120-749, Korea.
authors.forename: Hong-Kyung
authors.initials: HK
authors.lastname: Kim
authors.affiliation: Department of Life Science and Research Center for Cellular Homeostasis, Ewha Womans University, Seoul 120-750, Korea.
authors.forename: Chang-Yeol
authors.initials: CY
authors.lastname: Yeo
authors.affiliation: Department of Integrated OMICS for Biomedical Science, WCU Program, Yonsei University, Graduate School, Seoul 120-749, Korea.
authors.forename: Yangsin
authors.initials: Y
authors.lastname: Lee
authors.affiliation: Department of Integrated OMICS for Biomedical Science, WCU Program, Yonsei University, Graduate School, Seoul 120-749, Korea.
authors.forename: Jürgen
authors.initials: J
authors.lastname: Roth
authors.affiliation: Department of Systems Biology, Yonsei University, Seoul 120-749, Korea. Electronic address: leehjnt@yonsei.ac.kr.
authors.forename: JooHun
authors.initials: J
authors.lastname: Lee
mesh_terms: D000941:Antigens / Q000378:metabolism; D064652:Basal Bodies / Q000378:metabolism*; D002453:Cell Cycle; D002454:Cell Differentiation; D024462:Myosin Type II / Q000378:metabolism; D009253:Naegleria / Q000166:cytology* / Q000502:physiology*; D055503:Protein Multimerization; D014404:Tubulin / Q000378:metabolism
chemical_list: D000941:Antigens; D014404:Tubulin; C086178:pericentrin; D024462:Myosin Type II
keywords: Cell cycle-dependent duplicating complex; Naegleria pringsheimi.; de novo basal body/centriole formation