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Polo kinase regulates the localization and activity of the chromosomal passenger complex in meiosis and mitosis in Drosophila melanogaster.

Carmena M, Lombardia MO, Ogawa H, Earnshaw WC - Open Biol (2014)

Bottom Line: In this report, we show that Polo kinase is required for the correct localization and activity of the CPC in meiosis and mitosis.Study of the phenotype of different polo allele combinations compared to the effect of chemical inhibition revealed significant differences in the localization and activity of the CPC in diploid tissues.Our results shed new light on the mechanisms that control the activity of Aurora B in meiosis and mitosis.

View Article: PubMed Central - PubMed

Affiliation: The Wellcome Trust Centre for Cell Biology, Institute of Cell Biology, University of Edinburgh, Edinburgh EH9 3JR, UK mar.carmena@ed.ac.uk.

ABSTRACT
Cell cycle progression is regulated by members of the cyclin-dependent kinase (CDK), Polo and Aurora families of protein kinases. The levels of expression and localization of the key regulatory kinases are themselves subject to very tight control. There is increasing evidence that crosstalk between the mitotic kinases provides for an additional level of regulation. We have previously shown that Aurora B activates Polo kinase at the centromere in mitosis, and that the interaction between Polo and the chromosomal passenger complex (CPC) component INCENP is essential in this activation. In this report, we show that Polo kinase is required for the correct localization and activity of the CPC in meiosis and mitosis. Study of the phenotype of different polo allele combinations compared to the effect of chemical inhibition revealed significant differences in the localization and activity of the CPC in diploid tissues. Our results shed new light on the mechanisms that control the activity of Aurora B in meiosis and mitosis.

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Related in: MedlinePlus

Treatment with Plk1 inhibitor BI 2536 phenocopies polo mutant phenotype in neuroblast mitoses. (a) Control (DMSO-treated) third instar larval neuroblasts show normal localization of the CPC, whereas BI 2536-treated ones (b) show CPC mislocalization phenotypes similar to those observed in polo mutants. Green, α-tubulin; red, INCENP; blue, DNA; scale bars, 5 µm.
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RSOB140162F5: Treatment with Plk1 inhibitor BI 2536 phenocopies polo mutant phenotype in neuroblast mitoses. (a) Control (DMSO-treated) third instar larval neuroblasts show normal localization of the CPC, whereas BI 2536-treated ones (b) show CPC mislocalization phenotypes similar to those observed in polo mutants. Green, α-tubulin; red, INCENP; blue, DNA; scale bars, 5 µm.

Mentions: We next questioned whether the observed defects in CPC localization had an impact on the activity of Aurora B kinase. We monitored this by quantification of the levels of phosphorylation of the Aurora B substrate Histone3 Serine10—H3Ser10Ph (and H3Ser28Ph, data not shown). In order to assess the difference between the effects of depleting Polo protein levels in polo mutants versus those resulting from inhibition of its kinase activity (in which the protein is still present), we compared the levels of H3Ser10Ph in wild-type neuroblasts treated with the Plk1 inhibitor BI 2536 with those observed in neuroblasts from various combinations of polo mutants (figures 5 and 6; electronic supplementary material, figures S3 and S4). BI 2536 treatment of wild-type neuroblasts results in an elevated mitotic index compared to wild-type (18 ± 1.2%; n = 1000 per experiment). Drug treatment also phenocopies the CPC mislocalization phenotypes observed in polo mutants (figure 5). Thus, the phenotype observed after treatment with inhibitor has a much higher penetrance than that observed in polo1/polo1 neuroblasts (data not shown). This is most probably explained by the residual enzymatic activity in the Polo1 mutant kinase.Figure 5.


Polo kinase regulates the localization and activity of the chromosomal passenger complex in meiosis and mitosis in Drosophila melanogaster.

Carmena M, Lombardia MO, Ogawa H, Earnshaw WC - Open Biol (2014)

Treatment with Plk1 inhibitor BI 2536 phenocopies polo mutant phenotype in neuroblast mitoses. (a) Control (DMSO-treated) third instar larval neuroblasts show normal localization of the CPC, whereas BI 2536-treated ones (b) show CPC mislocalization phenotypes similar to those observed in polo mutants. Green, α-tubulin; red, INCENP; blue, DNA; scale bars, 5 µm.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4248065&req=5

RSOB140162F5: Treatment with Plk1 inhibitor BI 2536 phenocopies polo mutant phenotype in neuroblast mitoses. (a) Control (DMSO-treated) third instar larval neuroblasts show normal localization of the CPC, whereas BI 2536-treated ones (b) show CPC mislocalization phenotypes similar to those observed in polo mutants. Green, α-tubulin; red, INCENP; blue, DNA; scale bars, 5 µm.
Mentions: We next questioned whether the observed defects in CPC localization had an impact on the activity of Aurora B kinase. We monitored this by quantification of the levels of phosphorylation of the Aurora B substrate Histone3 Serine10—H3Ser10Ph (and H3Ser28Ph, data not shown). In order to assess the difference between the effects of depleting Polo protein levels in polo mutants versus those resulting from inhibition of its kinase activity (in which the protein is still present), we compared the levels of H3Ser10Ph in wild-type neuroblasts treated with the Plk1 inhibitor BI 2536 with those observed in neuroblasts from various combinations of polo mutants (figures 5 and 6; electronic supplementary material, figures S3 and S4). BI 2536 treatment of wild-type neuroblasts results in an elevated mitotic index compared to wild-type (18 ± 1.2%; n = 1000 per experiment). Drug treatment also phenocopies the CPC mislocalization phenotypes observed in polo mutants (figure 5). Thus, the phenotype observed after treatment with inhibitor has a much higher penetrance than that observed in polo1/polo1 neuroblasts (data not shown). This is most probably explained by the residual enzymatic activity in the Polo1 mutant kinase.Figure 5.

Bottom Line: In this report, we show that Polo kinase is required for the correct localization and activity of the CPC in meiosis and mitosis.Study of the phenotype of different polo allele combinations compared to the effect of chemical inhibition revealed significant differences in the localization and activity of the CPC in diploid tissues.Our results shed new light on the mechanisms that control the activity of Aurora B in meiosis and mitosis.

View Article: PubMed Central - PubMed

Affiliation: The Wellcome Trust Centre for Cell Biology, Institute of Cell Biology, University of Edinburgh, Edinburgh EH9 3JR, UK mar.carmena@ed.ac.uk.

ABSTRACT
Cell cycle progression is regulated by members of the cyclin-dependent kinase (CDK), Polo and Aurora families of protein kinases. The levels of expression and localization of the key regulatory kinases are themselves subject to very tight control. There is increasing evidence that crosstalk between the mitotic kinases provides for an additional level of regulation. We have previously shown that Aurora B activates Polo kinase at the centromere in mitosis, and that the interaction between Polo and the chromosomal passenger complex (CPC) component INCENP is essential in this activation. In this report, we show that Polo kinase is required for the correct localization and activity of the CPC in meiosis and mitosis. Study of the phenotype of different polo allele combinations compared to the effect of chemical inhibition revealed significant differences in the localization and activity of the CPC in diploid tissues. Our results shed new light on the mechanisms that control the activity of Aurora B in meiosis and mitosis.

Show MeSH
Related in: MedlinePlus