title: Plant Aurora kinases play a role in maintenance of primary meristems and control of endoreduplication.
abstract: • The conserved family of Aurora kinases has multiple functions during mitosis. The roles of plant Aurora kinases have been characterized using inhibitor treatments. • We down-regulated Aurora kinases in Arabidopsis thaliana using RNA interference (RNAi). We carried out a detailed phenotypic analysis of Aurora RNAi plants, biochemical and microscopic studies of AtAurora1 kinase together with AtTPX2 (targeting protein for Xklp2) and γ-tubulin. • Cell division defects were observed in plants with reduced expression of Aurora kinases. Furthermore, the maintenance of primary meristems was compromised and RNAi seedlings entered endoreduplication prematurely. AtAurora1, its activator AtTPX2, and γ-tubulin were associated with microtubules in vitro; they were attached to regrowing kinetochore microtubules and colocalized on spindle microtubules and with a subset of early phragmoplast microtubules. Only the AtAurora1 kinase was translocated to the area of the cell plate. • RNAi silencing of Aurora kinases showed that, in addition to their function in regulating mitosis, the kinases are required for maintaining meristematic activity and controlling the switch from meristematic cell proliferation to differentiation and endoreduplication. The colocalization and co-fractionation of AtAurora1 with AtTPX2, and γ-tubulin on microtubules in a cell cycle-specific manner suggests that AtAurora1 kinase may function to phosphorylate substrates that are critical to the spatiotemporal regulation of acentrosomal microtubule formation and organization.
authors.affiliation: Centre of the Region Haná for Biotechnological and Agricultural Research, Institute of Experimental Botany AS CR, v.v.i., Sokolovská 6, Olomouc 772 00, Czech Republic.
authors.forename: Beáta
authors.initials: B
authors.lastname: Petrovská
authors.affiliation: Institute of Experimental Botany, AS CR, v.v.i., Sokolovská 6, 772 00, Olomouc, Czech Republic.
authors.forename: Věra
authors.initials: V
authors.lastname: Cenklová
authors.affiliation: Institute of Experimental Botany, AS CR, v.v.i., Sokolovská 6, 772 00, Olomouc, Czech Republic.
authors.forename: Žaneta
authors.initials: Ž
authors.lastname: Pochylová
authors.affiliation: Institute of Microbiology, AS CR, v.v.i., Vídeňská 1083, 142 20 Prague 4, Czech Republic.
authors.forename: Hana
authors.initials: H
authors.lastname: Kourová
authors.affiliation: Institute of Microbiology, AS CR, v.v.i., Vídeňská 1083, 142 20 Prague 4, Czech Republic.
authors.forename: Anna
authors.initials: A
authors.lastname: Doskočilová
authors.affiliation: Institute of Microbiology, AS CR, v.v.i., Vídeňská 1083, 142 20 Prague 4, Czech Republic.
authors.forename: Ondřej
authors.initials: O
authors.lastname: Plíhal
authors.affiliation: Institute of Experimental Botany, AS CR, v.v.i., Sokolovská 6, 772 00, Olomouc, Czech Republic.
authors.forename: Lenka
authors.initials: L
authors.lastname: Binarová
authors.affiliation: Institute of Microbiology, AS CR, v.v.i., Vídeňská 1083, 142 20 Prague 4, Czech Republic.
authors.forename: Pavla
authors.initials: P
authors.lastname: Binarová
mesh_terms: D017360:Arabidopsis / Q000201:enzymology* / Q000235:genetics*; D029681:Arabidopsis Proteins / Q000378:metabolism*; D064127:Aurora Kinases; D002455:Cell Division; D015536:Down-Regulation; D020440:Gene Duplication / Q000235:genetics*; D018519:Meristem / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development*; D008869:Microtubule-Associated Proteins / Q000378:metabolism; D008870:Microtubules / Q000378:metabolism; D010641:Phenotype; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism*; D021381:Protein Transport; D034622:RNA Interference; D014404:Tubulin / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; D008869:Microtubule-Associated Proteins; C535123:TPX2 protein, Arabidopsis; D014404:Tubulin; C504614:AUR1 protein, Arabidopsis; D064127:Aurora Kinases; D017346:Protein Serine-Threonine Kinases