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The small molecule Hesperadin reveals a role for Aurora B in correcting kinetochore-microtubule attachment and in maintaining the spindle assembly checkpoint.

Hauf S, Cole RW, LaTerra S, Zimmer C, Schnapp G, Walter R, Heckel A, van Meel J, Rieder CL, Peters JM - J. Cell Biol. (2003)

Bottom Line: We have identified the small molecule Hesperadin as an inhibitor of chromosome alignment and segregation.Our data imply that Hesperadin causes this phenotype by inhibiting the function of the mitotic kinase Aurora B.Hesperadin also causes cells arrested by taxol or monastrol to enter anaphase within <1 h, whereas cells in nocodazole stay arrested for 3-5 h.

View Article: PubMed Central - PubMed

Affiliation: Research Institute of Molecular Pathology, Dr. Bohr-Gasse 7, 1030 Vienna, Austria.

ABSTRACT
The proper segregation of sister chromatids in mitosis depends on bipolar attachment of all chromosomes to the mitotic spindle. We have identified the small molecule Hesperadin as an inhibitor of chromosome alignment and segregation. Our data imply that Hesperadin causes this phenotype by inhibiting the function of the mitotic kinase Aurora B. Mammalian cells treated with Hesperadin enter anaphase in the presence of numerous monooriented chromosomes, many of which may have both sister kinetochores attached to one spindle pole (syntelic attachment). Hesperadin also causes cells arrested by taxol or monastrol to enter anaphase within <1 h, whereas cells in nocodazole stay arrested for 3-5 h. Together, our data suggest that Aurora B is required to generate unattached kinetochores on monooriented chromosomes, which in turn could promote bipolar attachment as well as maintain checkpoint signaling.

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Hesperadin-treated HeLa cells show alignment and segregation defects, but sister chromatid separation is intact. HeLa cells were left untreated or were treated with 50 nM Hesperadin for different periods of time before harvesting by mitotic shake off, followed by chromosome spreading and Giemsa staining. (a) Normal metaphase plate. Inset, normal degree of sister chromatid resolution. Compare the gap between sisters (arrow) in a and c. (b) Normal onset of anaphase. (c) Typical appearance of a late prometaphase in Hesperadin-treated cultures. Defects in alignment and sister chromatid resolution (arrow) are apparent. Some chromosomes are bent at the centromeric region (inset, examples marked by squares), implying microtubule attachment. (d–f) Typical appearance of early anaphases in Hesperadin-treated cells. Chromosomes often seem to be segregated to opposite poles, but many sister chromatids stay in close proximity (double arrows). One example of sister chromatids being pulled to opposite poles is marked by arrowheads. (g and h) Typical appearance of chromatin decondensation in Hesperadin-treated cells. (i) Typical interphase in Hesperadin-treated cultures.
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fig4: Hesperadin-treated HeLa cells show alignment and segregation defects, but sister chromatid separation is intact. HeLa cells were left untreated or were treated with 50 nM Hesperadin for different periods of time before harvesting by mitotic shake off, followed by chromosome spreading and Giemsa staining. (a) Normal metaphase plate. Inset, normal degree of sister chromatid resolution. Compare the gap between sisters (arrow) in a and c. (b) Normal onset of anaphase. (c) Typical appearance of a late prometaphase in Hesperadin-treated cultures. Defects in alignment and sister chromatid resolution (arrow) are apparent. Some chromosomes are bent at the centromeric region (inset, examples marked by squares), implying microtubule attachment. (d–f) Typical appearance of early anaphases in Hesperadin-treated cells. Chromosomes often seem to be segregated to opposite poles, but many sister chromatids stay in close proximity (double arrows). One example of sister chromatids being pulled to opposite poles is marked by arrowheads. (g and h) Typical appearance of chromatin decondensation in Hesperadin-treated cells. (i) Typical interphase in Hesperadin-treated cultures.

Mentions: In the course of a synthesis program for novel indolinones, we tested the effect of several compounds on cell proliferation. One of these, Hesperadin (Fig. 1 A; Walter et al., 2002), had dramatic effects; HeLa cells treated with 50 nM of Hesperadin stopped proliferating but did not stop growing, and over a 6-d period, the cell diameter increased more than sevenfold (from ∼20 to >150 μm; Fig. 1 B). During this time, the cells acquired enlarged lobed nuclei (see Fig. 4 i). FACS® analysis revealed that the increase in nuclear size correlated with polyploidization, reaching a 32C DNA content on day 3 (Fig. 1 B; unpublished data). At later stages, FACS® could not be used to analyze these cells, presumably because they had grown too big to enter the measuring capillary.


The small molecule Hesperadin reveals a role for Aurora B in correcting kinetochore-microtubule attachment and in maintaining the spindle assembly checkpoint.

Hauf S, Cole RW, LaTerra S, Zimmer C, Schnapp G, Walter R, Heckel A, van Meel J, Rieder CL, Peters JM - J. Cell Biol. (2003)

Hesperadin-treated HeLa cells show alignment and segregation defects, but sister chromatid separation is intact. HeLa cells were left untreated or were treated with 50 nM Hesperadin for different periods of time before harvesting by mitotic shake off, followed by chromosome spreading and Giemsa staining. (a) Normal metaphase plate. Inset, normal degree of sister chromatid resolution. Compare the gap between sisters (arrow) in a and c. (b) Normal onset of anaphase. (c) Typical appearance of a late prometaphase in Hesperadin-treated cultures. Defects in alignment and sister chromatid resolution (arrow) are apparent. Some chromosomes are bent at the centromeric region (inset, examples marked by squares), implying microtubule attachment. (d–f) Typical appearance of early anaphases in Hesperadin-treated cells. Chromosomes often seem to be segregated to opposite poles, but many sister chromatids stay in close proximity (double arrows). One example of sister chromatids being pulled to opposite poles is marked by arrowheads. (g and h) Typical appearance of chromatin decondensation in Hesperadin-treated cells. (i) Typical interphase in Hesperadin-treated cultures.
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Related In: Results  -  Collection

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getmorefigures.php?uid=PMC2172906&req=5

fig4: Hesperadin-treated HeLa cells show alignment and segregation defects, but sister chromatid separation is intact. HeLa cells were left untreated or were treated with 50 nM Hesperadin for different periods of time before harvesting by mitotic shake off, followed by chromosome spreading and Giemsa staining. (a) Normal metaphase plate. Inset, normal degree of sister chromatid resolution. Compare the gap between sisters (arrow) in a and c. (b) Normal onset of anaphase. (c) Typical appearance of a late prometaphase in Hesperadin-treated cultures. Defects in alignment and sister chromatid resolution (arrow) are apparent. Some chromosomes are bent at the centromeric region (inset, examples marked by squares), implying microtubule attachment. (d–f) Typical appearance of early anaphases in Hesperadin-treated cells. Chromosomes often seem to be segregated to opposite poles, but many sister chromatids stay in close proximity (double arrows). One example of sister chromatids being pulled to opposite poles is marked by arrowheads. (g and h) Typical appearance of chromatin decondensation in Hesperadin-treated cells. (i) Typical interphase in Hesperadin-treated cultures.
Mentions: In the course of a synthesis program for novel indolinones, we tested the effect of several compounds on cell proliferation. One of these, Hesperadin (Fig. 1 A; Walter et al., 2002), had dramatic effects; HeLa cells treated with 50 nM of Hesperadin stopped proliferating but did not stop growing, and over a 6-d period, the cell diameter increased more than sevenfold (from ∼20 to >150 μm; Fig. 1 B). During this time, the cells acquired enlarged lobed nuclei (see Fig. 4 i). FACS® analysis revealed that the increase in nuclear size correlated with polyploidization, reaching a 32C DNA content on day 3 (Fig. 1 B; unpublished data). At later stages, FACS® could not be used to analyze these cells, presumably because they had grown too big to enter the measuring capillary.

Bottom Line: We have identified the small molecule Hesperadin as an inhibitor of chromosome alignment and segregation.Our data imply that Hesperadin causes this phenotype by inhibiting the function of the mitotic kinase Aurora B.Hesperadin also causes cells arrested by taxol or monastrol to enter anaphase within <1 h, whereas cells in nocodazole stay arrested for 3-5 h.

View Article: PubMed Central - PubMed

Affiliation: Research Institute of Molecular Pathology, Dr. Bohr-Gasse 7, 1030 Vienna, Austria.

ABSTRACT
The proper segregation of sister chromatids in mitosis depends on bipolar attachment of all chromosomes to the mitotic spindle. We have identified the small molecule Hesperadin as an inhibitor of chromosome alignment and segregation. Our data imply that Hesperadin causes this phenotype by inhibiting the function of the mitotic kinase Aurora B. Mammalian cells treated with Hesperadin enter anaphase in the presence of numerous monooriented chromosomes, many of which may have both sister kinetochores attached to one spindle pole (syntelic attachment). Hesperadin also causes cells arrested by taxol or monastrol to enter anaphase within <1 h, whereas cells in nocodazole stay arrested for 3-5 h. Together, our data suggest that Aurora B is required to generate unattached kinetochores on monooriented chromosomes, which in turn could promote bipolar attachment as well as maintain checkpoint signaling.

Show MeSH
Related in: MedlinePlus