title: Nek2 localizes to multiple sites in mitotic cells, suggesting its involvement in multiple cellular functions during the cell cycle.
abstract: Nek2 is a mammalian protein kinase that is structurally homologous to NIMA, a mitotic regulator in Aspergillus nidulans. To understand the possible cellular processes in which Nek2 participates during the cell cycle, we investigated the expression and subcellular localization of Nek2 in mitotic cells. The Nek2 protein levels were observed to be regulated in a cell cycle stage-specific manner in cultured cells. The cell cycle stage specificity of Nek2 expression was also confirmed in cells undergoing mitosis in vivo. Nek2 proteins were localized in both the nucleus and cytoplasm throughout the cell cycle, but exhibited dynamic changes in distribution, depending on the cell cycle stage. Nek2 was associated with chromosomes from prophase to metaphase and then was dissociated upon entering into anaphase. Nek2 then appeared at the midbody of the cytoplasmic bridge at telophase. Nek2 was also associated with the centrosome throughout the cell cycle as observed previously by others. Additionally, the nuclear localization of Nek2 was increased during S phase. Such dynamic behavior of Nek2 suggests that Nek2 may be a mitotic regulator that is involved in diverse cell cycle events.
authors.affiliation: School of Biological Sciences, Seoul National University, Seoul, 151-742, Korea.
authors.forename: Yong
authors.initials: Y
authors.lastname: Ha Kim
authors.forename: Jun
authors.initials: J
authors.lastname: Yeol Choi
authors.forename: Yeontae
authors.initials: Y
authors.lastname: Jeong
authors.forename: Debra J
authors.initials: DJ
authors.lastname: Wolgemuth
authors.forename: Kunsoo
authors.initials: K
authors.lastname: Rhee
mesh_terms: D000705:Anaphase / Q000502:physiology; D000818:Animals; D002453:Cell Cycle / Q000502:physiology; D018797:Cell Cycle Proteins / Q000378:metabolism; D002478:Cells, Cultured; D018385:Centrosome / Q000378:metabolism; D002875:Chromosomes / Q000378:metabolism; D005260:Female; D005347:Fibroblasts / Q000166:cytology / Q000378:metabolism*; D006801:Humans; D008677:Metaphase / Q000502:physiology; D051379:Mice; D008938:Mitosis / Q000502:physiology*; D000072379:NIMA-Related Kinases; D006080:Ovarian Follicle / Q000166:cytology; D011418:Prophase / Q000502:physiology; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism*; D021381:Protein Transport / Q000502:physiology; D051381:Rats; D016196:S Phase / Q000502:physiology; D013692:Telophase / Q000502:physiology
chemical_list: D018797:Cell Cycle Proteins; C089441:NEK2 protein, human; D000072379:NIMA-Related Kinases; C490317:Nek2 protein, mouse; D017346:Protein Serine-Threonine Kinases