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Mitotic progression becomes irreversible in prometaphase and collapses when Wee1 and Cdc25 are inhibited
Mitosis requires precise coordination of multiple global reorganizations of the nucleus and cytoplasm. Cyclin-dependent kinase 1 (Cdk1) is the primary upstream kinase that directs mitotic progression by phosphorylation of a large number of substrate proteins. Cdk1 activation reaches the peak level d...
Autores principales: | , , , , |
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Formato: | Texto |
Lenguaje: | English |
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The American Society for Cell Biology
2011
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3078080/ https://www.ncbi.nlm.nih.gov/pubmed/21325631 http://dx.doi.org/10.1091/mbc.E10-07-0599 |
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author | Potapova, Tamara A. Sivakumar, Sushama Flynn, Jennifer N. Li, Rong Gorbsky, Gary J. |
author_facet | Potapova, Tamara A. Sivakumar, Sushama Flynn, Jennifer N. Li, Rong Gorbsky, Gary J. |
author_sort | Potapova, Tamara A. |
collection | PubMed |
description | Mitosis requires precise coordination of multiple global reorganizations of the nucleus and cytoplasm. Cyclin-dependent kinase 1 (Cdk1) is the primary upstream kinase that directs mitotic progression by phosphorylation of a large number of substrate proteins. Cdk1 activation reaches the peak level due to positive feedback mechanisms. By inhibiting Cdk chemically, we showed that, in prometaphase, when Cdk1 substrates approach the peak of their phosphorylation, cells become capable of proper M-to-G1 transition. We interfered with the molecular components of the Cdk1-activating feedback system through use of chemical inhibitors of Wee1 and Myt1 kinases and Cdc25 phosphatases. Inhibition of Wee1 and Myt1 at the end of the S phase led to rapid Cdk1 activation and morphologically normal mitotic entry, even in the absence of G2. Dampening Cdc25 phosphatases simultaneously with Wee1 and Myt1 inhibition prevented Cdk1/cyclin B kinase activation and full substrate phosphorylation and induced a mitotic “collapse,” a terminal state characterized by the dephosphorylation of mitotic substrates without cyclin B proteolysis. This was blocked by the PP1/PP2A phosphatase inhibitor, okadaic acid. These findings suggest that the positive feedback in Cdk activation serves to overcome the activity of Cdk-opposing phosphatases and thus sustains forward progression in mitosis. |
format | Text |
id | pubmed-3078080 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2011 |
publisher | The American Society for Cell Biology |
record_format | MEDLINE/PubMed |
spelling | pubmed-30780802011-06-30 Mitotic progression becomes irreversible in prometaphase and collapses when Wee1 and Cdc25 are inhibited Potapova, Tamara A. Sivakumar, Sushama Flynn, Jennifer N. Li, Rong Gorbsky, Gary J. Mol Biol Cell Articles Mitosis requires precise coordination of multiple global reorganizations of the nucleus and cytoplasm. Cyclin-dependent kinase 1 (Cdk1) is the primary upstream kinase that directs mitotic progression by phosphorylation of a large number of substrate proteins. Cdk1 activation reaches the peak level due to positive feedback mechanisms. By inhibiting Cdk chemically, we showed that, in prometaphase, when Cdk1 substrates approach the peak of their phosphorylation, cells become capable of proper M-to-G1 transition. We interfered with the molecular components of the Cdk1-activating feedback system through use of chemical inhibitors of Wee1 and Myt1 kinases and Cdc25 phosphatases. Inhibition of Wee1 and Myt1 at the end of the S phase led to rapid Cdk1 activation and morphologically normal mitotic entry, even in the absence of G2. Dampening Cdc25 phosphatases simultaneously with Wee1 and Myt1 inhibition prevented Cdk1/cyclin B kinase activation and full substrate phosphorylation and induced a mitotic “collapse,” a terminal state characterized by the dephosphorylation of mitotic substrates without cyclin B proteolysis. This was blocked by the PP1/PP2A phosphatase inhibitor, okadaic acid. These findings suggest that the positive feedback in Cdk activation serves to overcome the activity of Cdk-opposing phosphatases and thus sustains forward progression in mitosis. The American Society for Cell Biology 2011-04-15 /pmc/articles/PMC3078080/ /pubmed/21325631 http://dx.doi.org/10.1091/mbc.E10-07-0599 Text en © 2011 Potapova et al. This article is distributed by The American Society for Cell Biology under license from the author(s). Two months after publication it is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0). “ASCB®,“ “The American Society for Cell Biology®,” and “Molecular Biology of the Cell®” are registered trademarks of The American Society of Cell Biology. |
spellingShingle | Articles Potapova, Tamara A. Sivakumar, Sushama Flynn, Jennifer N. Li, Rong Gorbsky, Gary J. Mitotic progression becomes irreversible in prometaphase and collapses when Wee1 and Cdc25 are inhibited |
title | Mitotic progression becomes irreversible in prometaphase and collapses when Wee1 and Cdc25 are inhibited |
title_full | Mitotic progression becomes irreversible in prometaphase and collapses when Wee1 and Cdc25 are inhibited |
title_fullStr | Mitotic progression becomes irreversible in prometaphase and collapses when Wee1 and Cdc25 are inhibited |
title_full_unstemmed | Mitotic progression becomes irreversible in prometaphase and collapses when Wee1 and Cdc25 are inhibited |
title_short | Mitotic progression becomes irreversible in prometaphase and collapses when Wee1 and Cdc25 are inhibited |
title_sort | mitotic progression becomes irreversible in prometaphase and collapses when wee1 and cdc25 are inhibited |
topic | Articles |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3078080/ https://www.ncbi.nlm.nih.gov/pubmed/21325631 http://dx.doi.org/10.1091/mbc.E10-07-0599 |
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