GO:0001100 negative regulation of exit from mitosis: Cell Cycle Checkpoint Control, Genes, Functions and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0001100 describes the biological process that inhibits progression from anaphase/telophase (high mitotic CDK activity) to G1 (low mitotic CDK activity).
• The process is essential for maintaining mitotic CDK activity and preventing premature exit from mitosis, thereby ensuring proper chromosome segregation and cell division.
• Key regulators include PP2A, Cdc25C, Cdk1, Cdc15, Dbf2, p31comet, Mad2, PIN1, APC/C(CDH1), TRIP12, MCL-1, and protein kinase C.
• Dysregulation of negative regulation of exit from mitosis can lead to aneuploidy, genomic instability, and cancer.
• Experimental approaches to study this process include knockout, point mutation, knock-in, and overexpression models, as well as CRISPR library screening and bioinformatics.
• Understanding this process provides insights into cell cycle control, mitotic checkpoints, and potential therapeutic targets in oncology.
Description
The negative regulation of exit from mitosis (GO:0001100) is a critical biological process that prevents cells from prematurely exiting mitosis, ensuring accurate chromosome segregation and genomic stability. This process is defined as any process involved in the inhibition of progression from anaphase/telophase (high mitotic CDK activity) to G1 (low mitotic CDK activity). It is essential for maintaining the mitotic state until all chromosomes are properly attached to the spindle and segregated. Researchers study this process to understand how cells regulate the timing of mitotic exit and how errors contribute to diseases such as cancer. The negative regulation of exit from mitosis involves a complex network of proteins, including kinases, phosphatases, and ubiquitin ligases, that coordinate to keep CDK activity high until the appropriate time. Key players include the PP2A phosphatase, which regulates Cdc25C and Cdk1, the mitotic exit network kinases Cdc15 and Dbf2, and the spindle assembly checkpoint protein p31comet, which extracts Mad2 from the mitotic checkpoint complex to promote efficient mitotic exit. Additionally, the E3 ubiquitin ligase TRIP12 controls exit from mitosis via positive regulation of MCL-1 in response to Taxol, and the reciprocal antagonism of PIN1 and APC/C(CDH1) governs mitotic protein stability and cell cycle entry. Protein kinase C is also involved in cell cycle modulation, and PP2A-B55 targets, such as emerin, are regulated during nuclear envelope reassembly. This article provides a comprehensive overview of the negative regulation of exit from mitosis, covering its definition, importance, molecular mechanisms, key genes, disease associations, and research methods, including CRISPR-based approaches.
negative regulation of exit from mitosis At A Glance
| GO ID | GO:0001100 |
|---|---|
| GO term | negative regulation of exit from mitosis |
| Ontology | biological_process |
| Synonym | down regulation of exit from mitosis, down-regulation of exit from mitosis, downregulation of exit from mitosis, inhibition of exit from mitosis |
| Major function | Inhibition of progression from anaphase/telophase (high mitotic CDK activity) to G1 (low mitotic CDK activity) |
| Related processes | Mitotic cell cycle, spindle assembly checkpoint, chromosome segregation |
| Key regulators | PP2A, Cdc25C, Cdk1, Cdc15, Dbf2, p31comet, Mad2, PIN1, APC/C(CDH1), TRIP12, MCL-1, protein kinase C |
| Disease relevance | Cancer, genomic instability, aneuploidy |
What Is GO:0001100?
The negative regulation of exit from mitosis (GO:0001100) refers to any process that inhibits the progression from anaphase/telophase, when mitotic CDK activity is high, to G1 phase, when mitotic CDK activity is low. In other words, it is a regulatory mechanism that keeps cells in mitosis and prevents them from exiting too early, ensuring that cell division is completed accurately before the cell cycle continues.
Why Is negative regulation of exit from mitosis Important in Cell Biology?
The negative regulation of exit from mitosis is crucial for maintaining genomic stability and preventing premature cell division, which can lead to aneuploidy and cancer. Understanding this process is essential for researchers studying cell cycle control, mitotic checkpoints, and the development of targeted cancer therapies.
• Prevents premature exit from mitosis, ensuring accurate chromosome segregation.
• Maintains high mitotic CDK activity until all chromosomes are properly attached to the spindle.
• Dysregulation leads to aneuploidy and genomic instability, hallmarks of cancer.
• Provides potential therapeutic targets for cancer treatment, such as TRIP12 and MCL-1.
• Involved in the response to chemotherapeutic agents like Taxol.
• Regulates cell cycle entry through PIN1-APC/C(CDH1) antagonism.
• Coordinates with the spindle assembly checkpoint via p31comet and Mad2.
• Modulated by protein kinase C signaling.
• PP2A-B55 targets, such as emerin, are regulated during nuclear envelope reassembly.
• Essential for understanding basic cell cycle mechanisms and developing new research models.
What Happens During negative regulation of exit from mitosis?
Maintenance of High Mitotic CDK Activity
In simple terms: The cell keeps the engine of cell division running to prevent it from stopping too early.
During mitosis, high CDK activity is maintained by the negative regulation of exit from mitosis to ensure that the cell does not prematurely enter G1 phase. This is achieved through the inhibition of phosphatases that would otherwise dephosphorylate CDK substrates, such as PP2A, and through the regulation of Cdc25C and Cdk1. The balance between kinases and phosphatases is critical for proper mitotic progression.
Spindle Assembly Checkpoint and p31comet
In simple terms: A safety checkpoint ensures all chromosomes are properly attached before the cell divides.
The spindle assembly checkpoint (SAC) monitors chromosome attachment to the spindle and prevents mitotic exit until all chromosomes are properly bi-oriented. p31comet mediates the extraction of Mad2 from the mitotic checkpoint complex (MCC), promoting efficient mitotic exit once the checkpoint is satisfied. This process is a key part of the negative regulation of exit from mitosis, as it ensures that exit occurs only after proper chromosome segregation.
Regulation of Mitotic Exit Network Kinases
In simple terms: Specific proteins act as switches to control when the cell can finish division.
The mitotic exit network (MEN) kinases Cdc15 and Dbf2 are regulated to control exit from mitosis. Their activity is tightly controlled to prevent premature exit, and they coordinate with other regulators to ensure timely progression. Rewiring of the exit from mitosis network has been studied to understand how these components interact.
Role of Ubiquitin Ligases and Proteolysis
In simple terms: Tagging proteins for destruction helps control the timing of cell division.
The E3 ubiquitin ligase TRIP12 controls exit from mitosis via positive regulation of MCL-1 in response to Taxol. Additionally, the reciprocal antagonism of PIN1 and APC/C(CDH1) governs mitotic protein stability and cell cycle entry. These ubiquitin-mediated processes are integral to the negative regulation of exit from mitosis by ensuring the timely degradation of specific proteins.
Phosphatase Regulation and Nuclear Envelope Reassembly
In simple terms: Enzymes that remove phosphate groups are controlled to allow proper rebuilding of the cell nucleus.
PP2A-B55 targets, such as emerin, are regulated during nuclear envelope reassembly in Drosophila. This regulation is part of the negative regulation of exit from mitosis, as it ensures that nuclear envelope reassembly occurs correctly after chromosome segregation. Protein kinase C is also involved in cell cycle modulation, adding another layer of regulation.
Key Genes Involved in GO:0001100 negative regulation of exit from mitosis
The following genes and proteins are key players in the negative regulation of exit from mitosis, based on published literature.
| Gene | Major Role | Research Relevance |
|---|---|---|
| TRIP12 | E3 ubiquitin ligase; controls exit from mitosis via positive regulation of MCL-1 in response to Taxol | Potential target for cancer therapy; studied in Taxol response |
| MCL-1 | Anti-apoptotic protein; regulated by TRIP12 to control mitotic exit | Involved in chemoresistance; model for drug response |
| PIN1 | Peptidyl-prolyl isomerase; antagonizes APC/C(CDH1) to govern mitotic protein stability | Regulates cell cycle entry; target for cancer research |
| APC/C(CDH1) | Ubiquitin ligase; targets proteins for degradation to promote mitotic exit | Key regulator of mitosis; studied in cell cycle control |
| PP2A | Phosphatase; regulates Cdc25C and Cdk1 to control mitotic exit | Central to mitotic exit; target for understanding phosphatase regulation |
| Cdc25C | Phosphatase; activates Cdk1; regulated by PP2A | Regulates CDK activity; model for phosphatase studies |
| Cdk1 | Cyclin-dependent kinase; maintains high mitotic CDK activity | Core mitotic kinase; target for cell cycle inhibitors |
| Cdc15 | Mitotic exit network kinase; regulates exit from mitosis | Studied in yeast models; conserved mechanism |
| Dbf2 | Mitotic exit network kinase; regulates exit from mitosis | Studied in yeast models; conserved mechanism |
| p31comet | Mediates extraction of Mad2 from the MCC to promote efficient mitotic exit | Regulates spindle assembly checkpoint; target for aneuploidy research |
| Mad2 | Spindle assembly checkpoint protein; component of the MCC | Key checkpoint regulator; model for checkpoint studies |
| Protein kinase C | Involved in cell cycle modulation | Potential regulator of mitotic exit; studied in signaling |
| Emerin | Nuclear envelope protein; regulated by PP2A-B55 during nuclear envelope reassembly | Model for nuclear envelope dynamics |
| Cdc20 | Activator of APC/C; regulates mitotic exit | Studied in cell cycle control |
| Cdh1 | Activator of APC/C; regulates mitotic exit and G1 maintenance | Studied in cell cycle control |
| Cyclin B | Regulatory subunit of Cdk1; must be degraded for mitotic exit | Target for cell cycle studies |
| Securin | Separase inhibitor; degraded to allow chromosome segregation | Model for proteolysis in mitosis |
| Separase | Cleaves cohesin to allow chromosome segregation | Studied in chromosome segregation |
How Is negative regulation of exit from mitosis Regulated?
The negative regulation of exit from mitosis is regulated by a complex network of kinases and phosphatases, including PP2A, Cdc25C, Cdk1, and the mitotic exit network kinases Cdc15 and Dbf2. The spindle assembly checkpoint, via p31comet and Mad2, also plays a critical role in regulating the timing of mitotic exit. Additionally, ubiquitin ligases such as APC/C(CDH1) and TRIP12 control the stability of key mitotic proteins, thereby influencing exit. Protein kinase C is also involved in cell cycle modulation, adding another layer of regulation.
negative regulation of exit from mitosis and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| TRIP12 | Cancer, chemoresistance | Knockout in cancer cell lines; overexpression for drug response |
| PIN1 | Cancer, cell cycle dysregulation | Point mutation to disrupt isomerase activity; knockout models |
| PP2A | Cancer, developmental disorders | Knockout of subunits; knock-in of mutations |
| p31comet | Aneuploidy, cancer | Knockout to study checkpoint; overexpression to enhance mitotic exit |
| Emerin | Nuclear envelope disorders, Emery-Dreifuss muscular dystrophy | Knock-in of mutations; knockout in Drosophila |
Cancer and Genomic Instability
Dysregulation of the negative regulation of exit from mitosis can lead to aneuploidy and genomic instability, which are hallmarks of cancer. For example, TRIP12 controls exit from mitosis via positive regulation of MCL-1 in response to Taxol, and its dysregulation may contribute to chemoresistance. The reciprocal antagonism of PIN1 and APC/C(CDH1) governs mitotic protein stability and cell cycle entry, and its disruption can promote tumorigenesis.
Chemoresistance
The negative regulation of exit from mitosis is involved in the response to chemotherapeutic agents such as Taxol. TRIP12-mediated regulation of MCL-1 affects cell survival in response to Taxol, suggesting that targeting this pathway could overcome chemoresistance.
Developmental Disorders
Proper regulation of mitotic exit is essential for normal development. Mutations in genes involved in this process, such as PP2A subunits, can lead to developmental disorders characterized by chromosomal instability. However, specific human diseases linked to these genes require further investigation.
From negative regulation of exit from mitosis-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| What is the role of TRIP12 in mitotic exit and Taxol response? | TRIP12 knockout cell lines; overexpression of TRIP12 |
| How does PIN1 antagonize APC/C(CDH1) to regulate mitotic protein stability? | PIN1 point mutant knock-in; APC/C(CDH1) knockout |
| How does PP2A regulate Cdc25C and Cdk1 during mitotic exit? | PP2A subunit knockout; Cdc25C phospho-mutant knock-in |
| What is the function of Cdc15 and Dbf2 in the mitotic exit network? | Yeast knockout strains; point mutations |
| How does p31comet mediate Mad2 extraction from the MCC? | p31comet knockout; tagged knock-in for imaging |
| What is the role of PP2A-B55 in nuclear envelope reassembly? | Emerin knock-in with phospho-dead mutations; PP2A-B55 knockdown |
How to Study the negative regulation of exit from mitosis Process
| Method | What It Measures | Typical Application |
|---|---|---|
| RNA-seq | Gene expression changes | Identifying transcriptional programs during mitotic exit |
| CRISPR library screening | Gene essentiality and function | Discovering regulators of mitotic exit |
| Phosphoproteomics | Phosphorylation sites and dynamics | Identifying PP2A-B55 substrates |
| Live-cell imaging | Protein localization and dynamics | Monitoring Cdc15/Dbf2 during mitotic exit |
| In vitro kinase assay | Kinase activity | Measuring Cdk1 activity |
| Ubiquitination assay | Protein ubiquitination | Assessing TRIP12 and APC/C activity |
| Flow cytometry | DNA content and cell cycle profile | Detecting aneuploidy and cell cycle arrest |
| Immunofluorescence | Protein localization and modifications | Visualizing emerin during nuclear envelope reassembly |
Genomic and Transcriptomic Approaches
RNA-seq and CRISPR library screening can identify genes involved in the negative regulation of exit from mitosis. For example, CRISPR screens have been used to identify regulators of mitotic exit. Bioinformatics analysis of transcriptomic data can reveal pathways and networks associated with this process.
Proteomic and Phosphoproteomic Analysis
Mass spectrometry-based proteomics can quantify changes in protein abundance and phosphorylation during mitotic exit. Studies have used phosphoproteomics to identify PP2A-B55 targets such as emerin. Proteomic analysis of APC/C(CDH1) substrates has revealed key regulators of mitotic exit.
Imaging and Live-Cell Analysis
Live-cell imaging with fluorescently tagged proteins (e.g., GFP-Cdc15, GFP-Dbf2) allows real-time monitoring of mitotic exit dynamics. High-content imaging can assess chromosome segregation and aneuploidy in cells with perturbed negative regulation of exit from mitosis.
Biochemical Assays
In vitro kinase and phosphatase assays can measure the activity of Cdk1, PP2A, and other regulators. Ubiquitination assays can assess the activity of TRIP12 and APC/C(CDH1).
How CRISPR Can Be Used to Study GO:0001100 negative regulation of exit from mitosis
Knockout
CRISPR knockout of genes involved in the negative regulation of exit from mitosis, such as TRIP12, PIN1, or PP2A subunits, can reveal their essential roles in mitotic progression and cell viability. Knockout cell lines are valuable for studying the consequences of losing negative regulation, such as premature mitotic exit and aneuploidy.
Point Mutation
CRISPR point mutation can be used to introduce specific amino acid changes in genes like Cdc25C or Cdk1 to study phosphorylation sites critical for negative regulation of exit from mitosis. Point mutations in PIN1 can disrupt its isomerase activity to dissect its role in mitotic protein stability.
Knock-in
CRISPR knock-in of tagged versions of proteins, such as GFP-Cdc15 or mCherry-Dbf2, allows real-time imaging of their dynamics during mitotic exit. Knock-in of phospho-dead or phospho-mimetic mutants of emerin can elucidate its regulation by PP2A-B55.
Overexpression
CRISPR-mediated overexpression of genes like TRIP12 or MCL-1 can be used to study their effects on mitotic exit and chemoresistance. Overexpression of p31comet can promote efficient mitotic exit by extracting Mad2 from the MCC.
How EDITGENE Supports negative regulation of exit from mitosis Research
Researchers studying negative regulation of exit from mitosis-related genes often need to determine whether a candidate gene is causally involved in the process, and CRISPR-based models are essential for this functional validation.
Contact EDITGENE today to design your custom CRISPR model for negative regulation of exit from mitosis research.
Frequently Asked Questions About negative regulation of exit from mitosis
What is negative regulation of exit from mitosis?
Negative regulation of exit from mitosis (GO:0001100) is a biological process that inhibits the progression from anaphase/telophase (high mitotic CDK activity) to G1 (low mitotic CDK activity), ensuring proper chromosome segregation.
What genes are involved in negative regulation of exit from mitosis?
Key genes include TRIP12, MCL-1, PIN1, APC/C(CDH1), PP2A, Cdc25C, Cdk1, Cdc15, Dbf2, p31comet, Mad2, and protein kinase C.
Why is negative regulation of exit from mitosis important?
It prevents premature exit from mitosis, maintains genomic stability, and ensures accurate cell division; dysregulation can lead to cancer and aneuploidy.
How is negative regulation of exit from mitosis studied?
It is studied using CRISPR knockout, point mutation, knock-in, overexpression models, RNA-seq, proteomics, imaging, and biochemical assays.
What diseases are associated with negative regulation of exit from mitosis?
Dysregulation is linked to cancer, chemoresistance, and genomic instability.
What is the role of PP2A in negative regulation of exit from mitosis?
PP2A regulates Cdc25C and Cdk1 to control mitotic exit, and its B55 subunit targets emerin during nuclear envelope reassembly.
How does p31comet regulate mitotic exit?
p31comet mediates the extraction of Mad2 from the mitotic checkpoint complex (MCC) to promote efficient mitotic exit.
What is the function of TRIP12 in mitosis?
TRIP12 is an E3 ubiquitin ligase that controls exit from mitosis via positive regulation of MCL-1 in response to Taxol.
How do PIN1 and APC/C(CDH1) interact in mitotic exit?
PIN1 and APC/C(CDH1) have reciprocal antagonism that governs mitotic protein stability and cell cycle entry.
What CRISPR models are available for studying negative regulation of exit from mitosis?
EDITGENE offers knockout, point mutation, knock-in, tagged knock-in, and overexpression models, as well as CRISPR library screening and bioinformatics services.
Conclusion
The negative regulation of exit from mitosis (GO:0001100) is a fundamental biological process that ensures accurate chromosome segregation and genomic stability by preventing premature mitotic exit. Its dysregulation is implicated in cancer and chemoresistance, making it a critical area of research. Advances in CRISPR-based models and bioinformatics are enabling deeper insights into the molecular mechanisms and potential therapeutic targets within this pathway.
References
- 1. Keyan KS et al.. 2023. E3 Ubiquitin Ligase TRIP12 Controls Exit from Mitosis via Positive Regulation of MCL-1 in Response to Taxol.. Cancers (Basel) 15(2) PMID: 36672454
- 2. Ke S et al.. 2024. Reciprocal antagonism of PIN1-APC/C(CDH1) governs mitotic protein stability and cell cycle entry.. Nat Commun 15(1):3220 PMID: 38622115
- 3. Forester CM et al.. 2007. Control of mitotic exit by PP2A regulation of Cdc25C and Cdk1.. Proc Natl Acad Sci U S A 104(50):19867-72 PMID: 18056802
- 4. Visintin R et al.. 2001. Regulation of the mitotic exit protein kinases Cdc15 and Dbf2.. Mol Biol Cell 12(10):2961-74 PMID: 11598184
- 5. Ciliberto A et al.. 2005. Rewiring the exit from mitosis.. Cell Cycle 4(8):1107-12 PMID: 15970669
- 6. Westhorpe FG et al.. 2011. p31comet-mediated extraction of Mad2 from the MCC promotes efficient mitotic exit.. J Cell Sci 124(Pt 22):3905-16 PMID: 22100920
- 7. Poli A et al.. 2014. Protein kinase C involvement in cell cycle modulation.. Biochem Soc Trans 42(5):1471-6 PMID: 25233434
- 8. Emond-Fraser V et al.. 2023. Identification of PP2A-B55 targets uncovers regulation of emerin during nuclear envelope reassembly in Drosophila.. Open Biol 13(7):230104 PMID: 37463656
