Journal article
High Mitotic Activity of Polo-like Kinase 1 Is Required for Chromosome Segregation and Genomic Integrity in Human Epithelial Cells
The Journal of biological chemistry, Vol.287(51), pp.42812-42825
12/14/2012
DOI: 10.1074/jbc.M112.412544
PMCID: PMC3525009
PMID: 23105120
Abstract
Protein kinases play key roles in regulating human cell biology, but manifold substrates and functions make it difficult to understand mechanism. We tested whether we could dissect functions of a pleiotropic mitotic kinase, Polo-like kinase 1 (Plk1), via distinct thresholds of kinase activity. We accomplished this by titrating Plk1 activity in RPE1 human epithelial cells using chemical genetics and verifying results in additional lines. We found that distinct activity thresholds are required for known functions of Plk1 including (from low to high activity) bipolar spindle formation, timely mitotic entry, and formation of a cytokinesis cleavage furrow. Subtle losses in Plk1 activity impaired chromosome congression and produced severe anaphase dysfunction characterized by poor separation of chromosome masses. These two phenotypes were separable, suggesting that they stem from distinct phosphorylation events. Impaired chromosome segregation in anaphase was the most sensitive to modest loss in Plk1 activity. Mechanistically, it was associated with unpaired sister chromatids with stretched kinetochores, suggestive of merotelic attachments. The C-terminal Polo box domain of Plk1 was required for its anaphase function, although it was dispensable for forming a bipolar spindle. The ultimate effect of partial inhibition of Plk1 was the formation of micronuclei, an increase in tetraploid progeny, and senescence. These results demonstrate that different thresholds of Plk1 activity can elicit distinct phenotypes, illustrating a general method for separating pleiotropic functions of a protein kinase even when these are executed close in time.
Details
- Title: Subtitle
- High Mitotic Activity of Polo-like Kinase 1 Is Required for Chromosome Segregation and Genomic Integrity in Human Epithelial Cells
- Creators
- Robert F. LeraMark E. Burkard - Univ Wisconsin, Dept Med, Madison, WI 53705 USA
- Resource Type
- Journal article
- Publication Details
- The Journal of biological chemistry, Vol.287(51), pp.42812-42825
- DOI
- 10.1074/jbc.M112.412544
- PMID
- 23105120
- PMCID
- PMC3525009
- NLM abbreviation
- J Biol Chem
- ISSN
- 0021-9258
- eISSN
- 1083-351X
- Publisher
- Amer Soc Biochemistry Molecular Biology Inc
- Number of pages
- 14
- Grant note
- R01 GM097245; P30 CA014520 / National Institutes of Health; United States Department of Health & Human Services; National Institutes of Health (NIH) - USA R01GM097245 / NATIONAL INSTITUTE OF GENERAL MEDICAL SCIENCES; United States Department of Health & Human Services; National Institutes of Health (NIH) - USA; NIH National Institute of General Medical Sciences (NIGMS) P30CA014520 / NATIONAL CANCER INSTITUTE; United States Department of Health & Human Services; National Institutes of Health (NIH) - USA; NIH National Cancer Institute (NCI) 062541_YCSA / Flight Attendant Medical Research Institute 9U54TR000021 / National Center for Advancing Translational Sciences; United States Department of Health & Human Services; National Institutes of Health (NIH) - USA; NIH National Center for Advancing Translational Sciences (NCATS)
- Language
- English
- Date published
- 12/14/2012
- Academic Unit
- Internal Medicine
- Record Identifier
- 9984700653902771
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