Anaphase Topsy-Turvy: Cdk1 a Securin, Separase a CKI

Stemmann, Olaf; Gorr, Ingo H.; Boos, Dominik

doi:10.4161/cc.5.1.2296

Cited by 31 publications

(21 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Alternatively, Cdc20p may function through different mechanisms. In other systems, blocking separase activity via CDK/cyclin Bdependent phosphorylation can also inhibit anaphase progression, but this is thought to act in concert with securin and/or compensate for its loss (32,33,71). Thus, Cdc20p is important for key stages of mitotic progression in C. albicans, as in other systems, but the absence of a conserved Pds1p/securin homologue suggests that it may target a different factor(s), consistent with other modes of cell cycle rewiring in the pathogen (12,22).…”

Section: Discussionmentioning

confidence: 99%

Orthologues of the Anaphase-Promoting Complex/Cyclosome Coactivators Cdc20p and Cdh1p Are Important for Mitotic Progression and Morphogenesis in Candida albicans

2011

View full text Add to dashboard Cite

The conserved anaphase-promoting complex/cyclosome (APC/C) system mediates protein degradation during mitotic progression. Conserved coactivators Cdc20p and Cdh1p regulate the APC/C during early to late mitosis and G 1 phase. Candida albicans is an important fungal pathogen of humans, and it forms highly polarized cells when mitosis is blocked through depletion of the polo-like kinase Cdc5p or other treatments. However, the mechanisms governing mitotic progression and associated polarized growth in the pathogen are poorly understood. In order to gain insights into these processes, we characterized C. albicans orthologues of Cdc20p and Cdh1p. Cdc20p-depleted cells were blocked in early or late mitosis with elevated levels of Cdc5p and the mitotic cyclin Clb2p, suggesting that Cdc20p is essential and has some conserved functions during mitosis. However, the yeast cells formed highly polarized buds in contrast to the large doublets of S. cerevisiae cdc20 mutants, implying a distinct role in morphogenesis. In comparison, cdh1⌬/cdh1⌬ cells were viable but showed enrichment of Clb2p and Cdc5p, suggesting that Cdh1p may influence mitotic exit. The cdh1⌬/cdh1⌬ phenotype was pleiotropic, consisting of normal or enlarged yeast, pseudohyphae, and some elongated buds, whereas S. cerevisiae cdh1⌬ yeast cells were reduced in size. Thus, C. albicans Cdh1p may have some distinct functions. Finally, absence of Cdh1p or Cdc20p had a minor or no effect on hyphal development, respectively. Overall, the results suggest that Cdc20p and Cdh1p may be APC/C activators that are important for mitosis but also morphogenesis in C. albicans. Their novel features imply additional variations in function and underscore rewiring in the emerging mitotic regulatory networks of the pathogen.

show abstract

Section: Discussionmentioning

confidence: 99%

Orthologues of the Anaphase-Promoting Complex/Cyclosome Coactivators Cdc20p and Cdh1p Are Important for Mitotic Progression and Morphogenesis in Candida albicans

2011

View full text Add to dashboard Cite

show abstract

“…63 Interestingly, in vertebrates separase itself can directly bind to Cdk1 and inhibit its kinase activity. 64,65 Spindle elongation is severely perturbed in budding yeast cells forced to undergo an artificial anaphase with high Cdk1 activity and no Cdc14 phosphatase activity. 60 Downregulation of Cdk1 activity to accomplish normal chromosome segregation is equally obvious in higher eukaryotes.…”

Section: Regulation Of Chromosome Segregation In Anaphasementioning

confidence: 99%

Cell cycle control of spindle elongation

Roostalu

Schiebel²,

Khmelinskii³

2010

Cell Cycle

View full text Add to dashboard Cite

“…Therefore, regulation at the level of the substrate seems unfit to explain how securin-free mammalian cells maintain proper timing and fidelity of sister chromatid separation in mitosis. Instead, it is likely that, in the absence of securin, at least the inhibitory aspect of separase regulation is taken over by Cdk1-cyclin B1 (14).…”

mentioning

confidence: 99%

Positive and Negative Regulation of Vertebrate Separase by Cdk1-Cyclin B1 May Explain Why Securin Is Dispensable

Hellmuth

Pöhlmann

Brown

et al. 2015

Journal of Biological Chemistry

Self Cite

View full text Add to dashboard Cite

Background: Separase, the trigger protease of eukaryotic anaphase, remains regulated in the absence of its inhibitor, securin. Results: Cdk1-cyclin B1 triggers precipitation of separase by phosphorylation but stabilizes it by inhibitory binding. Conclusion: Only separase that is first complexed by Cdk1-cyclin B1 can later be activated by cyclin B1 degradation. Significance: These minimal requirements of separase regulation could explain the faithful execution of anaphase in the absence of securin.

show abstract

Anaphase Topsy-Turvy: Cdk1 a Securin, Separase a CKI

Cited by 31 publications

References 26 publications

Orthologues of the Anaphase-Promoting Complex/Cyclosome Coactivators Cdc20p and Cdh1p Are Important for Mitotic Progression and Morphogenesis in Candida albicans

Orthologues of the Anaphase-Promoting Complex/Cyclosome Coactivators Cdc20p and Cdh1p Are Important for Mitotic Progression and Morphogenesis in Candida albicans

Cell cycle control of spindle elongation

Positive and Negative Regulation of Vertebrate Separase by Cdk1-Cyclin B1 May Explain Why Securin Is Dispensable

Contact Info

Product

Resources

About