GO:0140273 repair of mitotic kinetochore microtubule attachment defect: Mitotic Error Correction, Genes, Functions and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0140273 describes the biological process that corrects defective kinetochore-microtubule attachments during mitosis, ensuring accurate chromosome segregation.
• The process is essential for preventing aneuploidy and chromosomal instability, which are hallmarks of cancer and developmental disorders.
• Key proteins involved include spindle assembly checkpoint (SAC) components such as BUB1, BUBR1, MAD1, MAD2, and the chromosomal passenger complex (CPC).
• Defects in this repair pathway can lead to whole-chromosome missegregation and DNA damage response activation during mitosis.
• Research into GO:0140273 relies on live-cell imaging, proteomics, and CRISPR-based gene editing to dissect molecular mechanisms.
• EDITGENE provides CRISPR knockout, point mutation, knock-in, overexpression, and library screening services to study genes involved in this process.
Description
The accurate segregation of chromosomes during mitosis is critical for genomic stability. The process of repairing mitotic kinetochore microtubule attachment defects, annotated as GO:0140273, ensures that erroneous attachments are corrected before anaphase onset. This process is a subset of the mitotic cell cycle and is essential for preventing aneuploidy, a hallmark of cancer and various developmental disorders. Understanding the molecular players and regulatory mechanisms of this repair pathway is a major focus in cell biology and oncology research. This article provides a comprehensive overview of GO:0140273, integrating authoritative QuickGO data with verified PubMed literature to guide researchers in experimental design and therapeutic targeting.
repair of mitotic kinetochore microtubule attachment defect At A Glance
| GO ID | GO:0140273 |
|---|---|
| GO term | repair of mitotic kinetochore microtubule attachment defect |
| Ontology | biological_process |
| Synonym | correction of mitotic kinetochore microtubule attachment defects; repair of mitotic kinetochore microtubule attachment defects |
| Major function | Corrects defective kinetochore-microtubule attachments during mitosis to ensure accurate chromosome segregation |
| Related processes | Spindle assembly checkpoint, chromosome segregation, mitotic cell cycle |
| Cellular location | Kinetochore, mitotic spindle, centromere |
| Key regulators | Aurora B kinase, MPS1, BUB1, BUBR1, MAD1, MAD2, Cdc20 |
What Is GO:0140273?
GO:0140273, repair of mitotic kinetochore microtubule attachment defect, is defined as the mitotic cell cycle process where kinetochore microtubule attachment defects are corrected. This process ensures that each kinetochore attaches properly to microtubules from opposite spindle poles, a state known as amphitelic attachment. When incorrect attachments occur, such as merotelic or syntelic attachments, this repair mechanism resolves them to maintain chromosomal stability.
Why Is repair of mitotic kinetochore microtubule attachment defect Important in Cell Biology?
The repair of mitotic kinetochore microtubule attachment defects is crucial for maintaining genomic integrity. Errors in this process lead to aneuploidy, which is a common feature of cancer cells and is associated with tumor progression and drug resistance. Moreover, defects in this pathway can trigger mitotic catastrophe, a form of cell death that is exploited in cancer therapies. Therefore, understanding the molecular mechanisms of GO:0140273 is essential for developing novel therapeutic strategies and for interpreting the effects of chemotherapeutic agents that target mitosis.
• Prevents aneuploidy and chromosomal instability, which are hallmarks of cancer.
• Ensures proper chromosome segregation during mitosis, critical for development and tissue homeostasis.
• Defects in this process can lead to mitotic catastrophe and cell death.
• Plays a role in the cellular response to DNA damage during mitosis.
• Involved in the mechanism of action of anti-mitotic drugs used in chemotherapy.
• Provides potential targets for cancer therapy, as cancer cells often have weakened repair pathways.
• Essential for understanding the etiology of developmental disorders linked to chromosomal instability.
• Key to studying the coordination between the spindle assembly checkpoint and error correction.
• Relevant to aging and degenerative diseases where genomic instability accumulates.
• Offers insights into the evolution of mitosis and chromosome segregation mechanisms.
What Happens During repair of mitotic kinetochore microtubule attachment defect?
Detection of Attachment Defects
In simple terms: The cell senses when a chromosome is not properly attached to the spindle.
During mitosis, the spindle assembly checkpoint (SAC) monitors kinetochore-microtubule attachments. Proteins such as MPS1, BUB1, and BUBR1 detect improper attachments, including merotelic or syntelic configurations, and initiate a signaling cascade to delay anaphase. This surveillance ensures that only correctly attached chromosomes proceed to segregation.
Aurora B Kinase-Mediated Error Correction
In simple terms: Aurora B acts like a quality control inspector that destabilizes wrong attachments.
Aurora B kinase, part of the chromosomal passenger complex (CPC), phosphorylates kinetochore substrates to destabilize incorrect attachments. This phosphorylation promotes detachment of microtubules from kinetochores, allowing for a fresh attempt at proper attachment. The balance between Aurora B activity and phosphatase activity is critical for error correction.
Reattachment and Stabilization
In simple terms: Once the wrong attachment is removed, the kinetochore tries again to bind microtubules correctly.
Following error correction, kinetochores can form new attachments with microtubules. This process involves the recruitment of proteins such as NDC80 complex and the regulation by kinases like PLK1 and MPS1. Successful attachments are stabilized by tension and dephosphorylation, leading to SAC silencing.
Spindle Assembly Checkpoint Silencing
In simple terms: When all chromosomes are correctly attached, the checkpoint is turned off, allowing cell division to proceed.
Once all kinetochores achieve proper attachments, the SAC is satisfied and silenced. This involves the dissociation of SAC proteins from kinetochores and the activation of the anaphase-promoting complex/cyclosome (APC/C) by Cdc20, leading to sister chromatid separation. Defects in this silencing can result in aneuploidy.
Key Genes Involved in GO:0140273 repair of mitotic kinetochore microtubule attachment defect
The following genes and proteins are key players in the repair of mitotic kinetochore microtubule attachment defects, as supported by the verified literature.
| Gene | Major Role | Research Relevance |
|---|---|---|
| AURKB | Chromosomal passenger complex kinase; phosphorylates kinetochore substrates to correct attachments | Target for cancer therapy; inhibition causes aneuploidy |
| BUB1 | Spindle assembly checkpoint kinase; involved in error correction and SAC signaling | Mutations linked to cancer; studied for kinetochore recruitment |
| BUB1B | Spindle assembly checkpoint kinase; regulates chromosome segregation | Mutations cause mosaic variegated aneuploidy |
| MAD1L1 | SAC component; forms complex with MAD2 to inhibit APC/C | Required for checkpoint function; knockout causes missegregation |
| MAD2L1 | SAC component; sequesters Cdc20 to inhibit APC/C | Key effector of SAC; studied in cancer and aneuploidy |
| NDC80 | Kinetochore component; mediates microtubule attachment | Essential for chromosome segregation; target for mitotic drugs |
| PLK1 | Polo-like kinase; regulates kinetochore-microtubule attachment and SAC | Overexpressed in cancers; inhibitor in clinical trials |
| MPS1 | Monopolar spindle 1 kinase; essential for SAC and error correction | Target for cancer therapy; inhibitors under development |
| CDC20 | Activator of APC/C; required for anaphase onset | Regulated by SAC; overexpression linked to cancer |
| CDK1 | Cyclin-dependent kinase 1; master regulator of mitosis | Phosphorylates multiple substrates; target for anti-mitotic drugs |
| CDC25B | Phosphatase; activates CDK1-Cyclin B | Involved in mitotic entry; regulated by Survivin |
| BIRC5 | Survivin; chromosomal passenger complex component; regulates mitosis | Overexpressed in cancers; target for therapy |
| Cdc5L | Pre-mRNA splicing factor; required for mitotic progression | Depletion causes mitotic catastrophe |
| DNA-PKcs | DNA-dependent protein kinase; involved in DNA damage response during mitosis | Required for chromosomal stability |
| CHK2 | Checkpoint kinase 2; activated by DNA damage during mitosis | Phosphorylates BRCA1 to ensure chromosomal stability |
| BRCA1 | Breast cancer type 1 susceptibility protein; involved in DNA repair and mitosis | Phosphorylated by CHK2; maintains chromosomal stability |
| Aurora A | Mitotic kinase; regulates spindle assembly and centrosome maturation | Overexpressed in cancers; target for inhibitors |
| TPX2 | Microtubule-associated protein; regulates Aurora A and spindle assembly | Required for mitotic spindle formation |
How Is repair of mitotic kinetochore microtubule attachment defect Regulated?
The repair of mitotic kinetochore microtubule attachment defects is tightly regulated by phosphorylation and dephosphorylation events. Aurora B kinase, in complex with INCENP, Survivin, and Borealin, phosphorylates kinetochore substrates to destabilize incorrect attachments. Conversely, phosphatases such as PP1 and PP2A counteract Aurora B activity to stabilize correct attachments. The spindle assembly checkpoint proteins, including MAD1, MAD2, BUB1, and BUBR1, monitor attachment status and regulate the timing of anaphase onset. Additionally, the DNA damage response kinases DNA-PKcs and CHK2 are activated during mitosis and contribute to chromosomal stability by regulating BRCA1. Cdc5L, a pre-mRNA splicing factor, is also required for mitotic progression, and its depletion leads to mitotic catastrophe.
repair of mitotic kinetochore microtubule attachment defect and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| BUB1B | Mosaic variegated aneuploidy syndrome; cancer predisposition | Knockout or point mutation in cell lines; mouse models |
| MAD1L1 | Colorectal cancer; aneuploidy | Knockout in HCT116; xenograft models |
| AURKB | Cancer; chromosomal instability | Overexpression or knockout in HeLa; inhibitor studies |
| Cdc5L | Mitotic catastrophe; cancer | Knockdown or knockout in HeLa; live-cell imaging |
| DNA-PKcs | Chromosomal instability; cancer | Knockout in MEFs; irradiation models |
Cancer and Chromosomal Instability
Defects in the repair of mitotic kinetochore microtubule attachment defects lead to chromosomal instability (CIN), a hallmark of many cancers. CIN promotes tumor heterogeneity and can drive cancer progression and drug resistance. For example, DNA damage response during mitosis can induce whole-chromosome missegregation, contributing to CIN. Mutations in SAC genes such as BUB1B and MAD1L1 are associated with mosaic variegated aneuploidy and cancer predisposition.
Mitotic Catastrophe and Cancer Therapy
Many anti-cancer drugs target mitosis, and cells with defective error correction are more sensitive to these agents. Depletion of Cdc5L, a splicing factor required for mitotic progression, triggers mitotic catastrophe, suggesting that targeting such factors could be therapeutic. Similarly, inhibition of Aurora B or MPS1 kinases induces mitotic catastrophe in cancer cells.
Developmental Disorders
Mutations in genes involved in chromosome segregation can cause developmental disorders characterized by aneuploidy. For instance, mutations in BUB1B cause mosaic variegated aneuploidy syndrome, which is associated with growth retardation and cancer predisposition. Proper regulation of mitotic error correction is essential for normal development.
From repair of mitotic kinetochore microtubule attachment defect-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Does gene X regulate error correction? | CRISPR knockout in HeLa or RPE1 cells, followed by live-cell imaging |
| What is the role of a specific phosphorylation site? | Point mutation (phospho-deficient or phospho-mimetic) knock-in |
| How does a disease-associated mutation affect function? | Knock-in of patient mutation using CRISPR |
| Where does protein X localize during mitosis? | Tagged knock-in (e.g., GFP) for live-cell imaging |
| Does overexpression of gene Y cause aneuploidy? | Overexpression via lentiviral transduction or CRISPR activation |
| Which genes are essential for error correction? | Genome-wide CRISPR library screening with FACS-based readout |
How to Study the repair of mitotic kinetochore microtubule attachment defect Process
| Method | What It Measures | Typical Application |
|---|---|---|
| Live-cell imaging | Chromosome segregation dynamics, lagging chromosomes | Assess error correction efficiency in knockout cells |
| BioID proximity proteomics | Protein-protein interactions at kinetochores | Map SAC protein networks |
| CRISPR knockout screen | Gene essentiality for chromosome segregation | Identify novel error correction genes |
| Phosphoproteomics | Kinase substrate identification | Find Aurora B substrates |
| Immunofluorescence | Kinetochore-microtubule attachment status | Quantify misattachments in fixed cells |
| Flow cytometry | DNA content, aneuploidy | Measure chromosomal instability |
| Western blot | Protein expression and phosphorylation | Validate knockout or overexpression |
| RNA-seq | Transcriptional changes upon gene perturbation | Assess cellular stress responses |
Live-Cell Imaging
Live-cell imaging using fluorescently tagged histones and kinetochore proteins allows real-time visualization of chromosome segregation and error correction. This method can quantify the frequency of lagging chromosomes and anaphase bridges, indicators of defective repair.
Proteomics and Proximity Mapping
Proximity-dependent biotinylation (e.g., BioID) coupled with mass spectrometry can map the interactome of SAC proteins, revealing novel components of the error correction machinery. This approach identifies dynamic associations during mitosis.
CRISPR-Based Genetic Screens
Genome-wide CRISPR knockout or activation screens can identify genes whose loss or gain affects chromosome segregation. These screens typically use FACS to sort cells with missegregated chromosomes or reporters of aneuploidy.
Phosphoproteomics
Quantitative phosphoproteomics can identify substrates of Aurora B and other mitotic kinases, providing insights into the signaling pathways that correct attachment defects.
How CRISPR Can Be Used to Study GO:0140273 repair of mitotic kinetochore microtubule attachment defect
Knockout
CRISPR knockout of genes such as AURKB, BUB1, or MPS1 in cell lines like HeLa or RPE1 can reveal their essential roles in error correction. Knockout cells typically exhibit increased lagging chromosomes and aneuploidy, which can be quantified by live-cell imaging.
Point Mutation
Introducing point mutations (e.g., kinase-dead or phospho-mutant) into genes like AURKB or BUB1 using CRISPR can dissect specific domains required for error correction. This approach avoids complete loss of protein and allows study of separation-of-function mutants.
Knock-in
Knock-in of fluorescent tags (e.g., GFP) or disease-associated mutations into endogenous loci enables real-time tracking of proteins and modeling of patient-specific mutations. For example, tagging NDC80 with GFP allows visualization of kinetochore dynamics.
Overexpression
CRISPR activation (CRISPRa) or lentiviral overexpression can model gene amplification observed in cancers. Overexpression of AURKB or PLK1 may induce chromosomal instability and serve as a tool to study oncogenic roles.
How EDITGENE Supports repair of mitotic kinetochore microtubule attachment defect Research
Researchers studying repair of mitotic kinetochore microtubule attachment defect-related genes often need to determine whether a candidate gene is causally involved in error correction or is merely correlated with mitotic defects. EDITGENE provides a comprehensive suite of CRISPR services to enable precise genetic perturbations and functional validation.
Contact EDITGENE today to design your custom CRISPR model for repair of mitotic kinetochore microtubule attachment defect research.
Frequently Asked Questions About repair of mitotic kinetochore microtubule attachment defect
What is GO:0140273?
GO:0140273 is the Gene Ontology term for the biological process that corrects defective kinetochore-microtubule attachments during mitosis, ensuring accurate chromosome segregation.
What genes are involved in repair of mitotic kinetochore microtubule attachment defect?
Key genes include AURKB, BUB1, BUB1B, MAD1L1, MAD2L1, NDC80, PLK1, MPS1, and CDC20, among others.
Why is repair of mitotic kinetochore microtubule attachment defect important?
It prevents aneuploidy and chromosomal instability, which are hallmarks of cancer and developmental disorders.
How is repair of mitotic kinetochore microtubule attachment defect regulated?
It is regulated by Aurora B kinase, phosphatases, and the spindle assembly checkpoint proteins.
What diseases are associated with defects in this process?
Defects are linked to cancer, mosaic variegated aneuploidy, and other chromosomal instability syndromes.
What methods are used to study repair of mitotic kinetochore microtubule attachment defect?
Live-cell imaging, proteomics, CRISPR screens, and phosphoproteomics are commonly used.
Can CRISPR be used to study this process?
Yes, CRISPR knockout, point mutation, knock-in, and overexpression models are powerful tools to dissect gene function in error correction.
What is the role of Aurora B in error correction?
Aurora B phosphorylates kinetochore substrates to destabilize incorrect attachments, allowing for proper reattachment.
How does the spindle assembly checkpoint relate to error correction?
The SAC monitors attachment status and delays anaphase until all defects are corrected.
What happens if error correction fails?
Failure leads to whole-chromosome missegregation, aneuploidy, and potentially mitotic catastrophe or cancer.
Conclusion
The repair of mitotic kinetochore microtubule attachment defects (GO:0140273) is a fundamental process that safeguards genomic integrity during cell division. Its dysregulation contributes to cancer and developmental disorders, making it a critical area of research. By leveraging CRISPR-based models and advanced screening technologies, researchers can uncover novel therapeutic targets and deepen our understanding of mitosis. EDITGENE is committed to supporting this research with high-quality gene editing services.
References
- 1. Mu R et al.. 2014. Depletion of pre-mRNA splicing factor Cdc5L inhibits mitotic progression and triggers mitotic catastrophe.. Cell Death Dis 5(3):e1151 PMID: 24675469
- 2. Garcia YA et al.. 2021. Mapping Proximity Associations of Core Spindle Assembly Checkpoint Proteins.. J Proteome Res 20(7):3414-3427 PMID: 34087075
- 3. Cánovas PM. 2024. Survivin Mediates Mitotic Onset in HeLa Cells Through Activation of the Cdk1-Cdc25B Axis.. Res Sq PMID: 38464014
- 4. Bakhoum SF et al.. 2014. DNA-damage response during mitosis induces whole-chromosome missegregation.. Cancer Discov 4(11):1281-9 PMID: 25107667
- 5. Shang Z et al.. 2014. DNA-PKcs activates the Chk2-Brca1 pathway during mitosis to ensure chromosomal stability.. Oncogenesis 3(2):e85 PMID: 24492479
