Dissociating the centrosomal matrix protein AKAP450 from centrioles impairs centriole duplication and cell cycle progression.
Centrosomes provide docking sites for regulatory molecules involved in the control of the cell division cycle. The centrosomal matrix contains several proteins, which anchor kinases and phosphatases. The large A-Kinase Anchoring Protein AKAP450 is acting as a scaffolding protein for other components of the cell signaling machinery. We selectively perturbed the centrosome by modifying the cellular localization of AKAP450. We report that the expression in HeLa cells of the C terminus of AKAP450, which contains the centrosome-targeting domain of AKAP450 but not its coiled-coil domains or binding sites for signaling molecules, leads to the displacement of the endogenous centrosomal AKAP450 without removing centriolar or pericentrosomal components such as centrin, gamma-tubulin, or pericentrin. The centrosomal protein kinase A type II alpha was delocalized. We further show that this expression impairs cytokinesis and increases ploidy in HeLa cells, whereas it arrests diploid RPE1 fibroblasts in G1, thus further establishing a role of the centrosome in the regulation of the cell division cycle. Moreover, centriole duplication is interrupted. Our data show that the association between centrioles and the centrosomal matrix protein AKAP450 is critical for the integrity of the centrosome and for its reproduction.
Keryer
Guy
G
Unité Mixte Recherche 144-Centre National de la Recherche Scientifique-Institut Curie, F-75248, Paris, France.
Witczak
Oliwia
O
Delouvée
Annie
A
Kemmner
Wolfram A
WA
Rouillard
Danielle
D
Tasken
Kjetil
K
Bornens
Michel
M
D054758:A Kinase Anchor Proteins; D048868:Adaptor Proteins, Signal Transducing; D002352:Carrier Proteins / Q000096:biosynthesis / Q000378:metabolism*; D002453:Cell Cycle / Q000502:physiology*; D002455:Cell Division; D002502:Centrioles / Q000378:metabolism*; D054746:Cyclic AMP-Dependent Protein Kinase Type II; D017868:Cyclic AMP-Dependent Protein Kinases / Q000378:metabolism; D003598:Cytoskeletal Proteins; D006367:HeLa Cells; D006801:Humans; D011123:Polyploidy; D017434:Protein Structure, Tertiary
D054758:A Kinase Anchor Proteins; C119719:AKAP9 protein, human; D048868:Adaptor Proteins, Signal Transducing; D002352:Carrier Proteins; D003598:Cytoskeletal Proteins; D054746:Cyclic AMP-Dependent Protein Kinase Type II; D017868:Cyclic AMP-Dependent Protein Kinases