Casein kinase II is required for proper cell division and acts as a negative regulator of centrosome duplication inCaenorhabditiselegansembryos

Summary statementThe conserved protein kinase CK2 negatively regulates centrosome assembly and is required for proper cell cycle progression and cytokinesis in early C. elegans embryos.AbstractCentrosomes are the primary microtubule-organizing centers that orchestrate microtubule dynamics during the cell cycle. The correct number of centrosomes is pivotal for establishing bipolar mitotic spindles that ensure accurate segregation of chromosomes. Thus, centrioles must duplicate once per cell cycle, one daughter per mother centriole, the process of which requires highly coordinated actions among core factors and modulators. Protein phosphorylation is shown to regulate the stability, localization and activity of centrosome proteins. Here, we report the function of Casein Kinase II (CK2) in early C. elegans embryos. The catalytic subunit (KIN-3/CK2α) of CK2 localizes to nuclei, centrosomes and midbodies. Inactivating CK2 leads to cell division defects, including chromosome missegregation, cytokinesis failure and aberrant centrosome behavior. Furthermore, depletion or inhibiting kinase activity of CK2 results in elevated ZYG-1 levels at centrosomes, restoring centrosome duplication and embryonic viability to zyg-1 mutants. Our data suggest that CK2 functions in cell division and negatively regulates centrosome duplication in a kinase-dependent manner.

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Casein kinase II is a negative regulator of c-Jun DNA binding and AP-1 activity

Cell ◽

10.1016/0092-8674(92)90311-y ◽

1992 ◽

Vol 70 (5) ◽

pp. 777-789 ◽

Cited By ~ 239

Author(s):

Anning Lin ◽

Jeff Frost ◽

Tiliang Deng ◽

Tod Smeal ◽

Nadia Al-Alawi ◽

...

Keyword(s):

Dna Binding ◽

Casein Kinase Ii ◽

Casein Kinase ◽

Negative Regulator

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Involvement of protein kinase A and casein kinase II in the in vivo protein kinase activities in prophase arrested Xenopus oocytes

Bioscience Reports ◽

10.1007/bf01114688 ◽

1989 ◽

Vol 9 (3) ◽

pp. 351-358 ◽

Cited By ~ 5

Author(s):

Patrick cormier ◽

Odile Mulner-Lorillon ◽

René Ozon ◽

Robert Bellé

Keyword(s):

Cell Division ◽

Protein Kinase ◽

Protein Kinase A ◽

Xenopus Oocytes ◽

Kinase Inhibitor ◽

Casein Kinase Ii ◽

Casein Kinase ◽

Meiotic Cell ◽

Kinase A

In vivo β casein phosphorylation was analysed in Xenopus full-grown oocytes arrested in the prophase of the meiotic cell division. The phosphorylation was inhibited by the protein kinase inhibitor (PKI) and also by heparin (3 μg/ml; final concentration). β casein phosphorylation was increased by spermine (2 mM). Therefore, protein kinase A and casein kinase II are both active in vivo in full-grown oocytes and may be involved in the prophase arrest of meiotic cell division.

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APC/CFZR-1 Controls SAS-5 Levels to Regulate Centrosome Duplication in Caenorhabditis elegans

10.1101/186148 ◽

2017 ◽

Author(s):

Jeffrey C. Medley ◽

Lauren E. DeMeyer ◽

Megan M. Kabara ◽

Mi Hye Song

Keyword(s):

Cell Division ◽

Caenorhabditis Elegans ◽

Ubiquitin Proteasome System ◽

Mitotic Cell ◽

Early Embryo ◽

Negative Regulator ◽

Centrosome Duplication ◽

Microtubule Organizing Center ◽

Protein Levels ◽

And Function

ABSTRACTAs the primary microtubule-organizing center, centrosomes play a key role in establishing mitotic bipolar spindles that secure correct transmission of genomic content. For the fidelity of cell division, centrosome number must be strictly controlled by duplicating only once per cell cycle. Proper levels of centrosome proteins are shown to be critical for normal centrosome number and function. Overexpressing core centrosome factors leads to extra centrosomes, while depleting these factors results in centrosome duplication failure. In this regard, protein turnover by the ubiquitin-proteasome system provides a vital mechanism for the regulation of centrosome protein levels. Here, we report that FZR-1, the Caenorhabditis elegans homolog of Cdh1/Hct1/Fzr, a co-activator of the anaphase promoting complex/cyclosome (APC/C), an E3 ubiquitin ligase, functions as a negative regulator of centrosome duplication in the Caenorhabditis elegans embryo. During mitotic cell division in the early embryo, FZR-1 is associated with centrosomes and enriched at nuclei. Loss of fzr-1 function restores centrosome duplication and embryonic viability to the hypomorphic zyg-1(it25) mutant, in part, through elevated levels of SAS-5 at centrosomes. Our data suggest that the APC/CFZR-1 regulates SAS-5 levels by directly recognizing the conserved KEN-box motif, contributing to proper centrosome duplication. Together, our work shows that FZR-1 plays a conserved role in regulating centrosome duplication in Caenorhabditis elegans.

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