GO:0007100 mitotic centrosome separation: Mechanism, Genes, Functions and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0007100 mitotic centrosome separation is the biological process in which duplicated centrosomes split and move to opposite sides of the nucleus to form the two spindle poles.
• Centrosome separation is driven by kinesin motors, including the bimC family, and is coordinated with nuclear envelope breakdown and mitotic entry.
• Cyclin B1-Cdk1 activity continues after centrosome separation and controls subsequent mitotic progression.
• Adhesion signals and phase separation contribute to centrosome separation and mitotic structure assembly.
• Errors in centrosome separation are linked to mitotic defects, aneuploidy, and early embryonic genome unification errors.
• CRISPR knockout, point mutation, knock-in, and overexpression models enable causal testing of genes involved in mitotic centrosome separation.
Description
Mitotic centrosome separation (GO:0007100) is a conserved biological process that ensures the duplicated centrosome components are physically separated at the onset of mitosis, allowing each centrosome to become the core of a microtubule-organizing center that nucleates a radial aster. The two asters then move to opposite sides of the nucleus, establishing the bipolar mitotic spindle required for accurate chromosome segregation. This process is tightly coordinated with mitotic entry, nuclear lamina dynamics, and cell-cycle kinase activity. Defects in centrosome separation can lead to multipolar spindles, chromosome missegregation, and aneuploidy, making it a critical area of study in cancer biology and developmental biology. Researchers investigate this process using live-cell imaging, proteomics, and CRISPR-based genetic models to dissect the molecular players and their regulatory networks.
mitotic centrosome separation At A Glance
| GO ID | GO:0007100 |
|---|---|
| GO term | mitotic centrosome separation |
| Ontology | biological_process |
| Synonym | none |
| Major function | Separation of duplicated centrosomes to form two spindle poles |
| Definition | Separation of duplicated centrosome components at the beginning of mitosis; centriole pairs become separate microtubule organizing centers that nucleate asters and move to opposite sides of the nucleus. |
| Related cellular structure | Centrosome, centriole pair, aster, mitotic spindle |
| Key regulators | Kinesin motors (bimC family), Cyclin B1-Cdk1, PP2A-B55/SUR-6, nuclear lamina |
| Associated processes | Mitotic entry, nuclear envelope breakdown, spindle assembly, chromosome segregation |
What Is GO:0007100?
According to the Gene Ontology, GO:0007100 mitotic centrosome separation is defined as the separation of duplicated centrosome components at the beginning of mitosis. The centriole pair within each centrosome becomes part of a separate microtubule organizing center that nucleates a radial array of microtubules called an aster. The two asters move to opposite sides of the nucleus to form the two poles of the mitotic spindle.
Why Is mitotic centrosome separation Important in Cell Biology?
Mitotic centrosome separation is essential for forming a bipolar mitotic spindle, which ensures equal chromosome segregation and genomic stability. Disruption of this process can cause multipolar spindles, aneuploidy, and cell death, and has been implicated in cancer progression and embryonic developmental errors. Understanding the molecular mechanisms of centrosome separation provides insights into cell cycle control, cytoskeletal dynamics, and potential therapeutic targets for proliferative diseases.
• Ensures bipolar spindle formation and accurate chromosome segregation.
• Prevents aneuploidy and genomic instability associated with cancer.
• Coordinated with mitotic entry through Cyclin B1-Cdk1 and PP2A-B55/SUR-6.
• Requires kinesin motor activity, including the bimC family, for centrosome separation.
• Influenced by cell adhesion and integrin signaling in early mitosis.
• Phase separation mechanisms contribute to assembly of mitotic structures.
• Errors in centrosome separation are linked to early embryonic genome unification defects.
• Centriole inheritance and duplication are prerequisites for proper separation.
• Provides targets for cancer therapy and reproductive biology research.
• Studied using advanced imaging, proteomics, and CRISPR models.
What Happens During mitotic centrosome separation?
Initiation at mitotic entry
In simple terms: At the start of mitosis, the cell gets ready to split its centrosomes.
Mitotic centrosome separation begins at the onset of mitosis, when duplicated centrosomes need to move apart to form the two spindle poles. This step is coordinated with nuclear envelope breakdown and requires the activity of Cyclin B1-Cdk1, which continues after separation to control mitotic progression. The nuclear lamina and PP2A-B55/SUR-6 collaborate to regulate the timing of centrosome separation during mitotic entry.
Centriole pair splitting and aster formation
In simple terms: Each centrosome contains a pair of centrioles that separate and start organizing microtubules.
Within each centrosome, the centriole pair becomes part of a separate microtubule organizing center that nucleates a radial array of microtubules called an aster. Centriole inheritance ensures that each daughter cell receives the correct number of centrioles, a prerequisite for proper separation. The two asters then move to opposite sides of the nucleus to form the two poles of the mitotic spindle.
Motor-driven separation
In simple terms: Molecular motors push the centrosomes apart.
The bimC family of kinesins are essential bipolar mitotic motors that drive centrosome separation. These motors generate forces that slide microtubules and push the centrosomes apart, contributing to spindle bipolarity. Additional regulation by phase separation mechanisms may help assemble mitotic structures.
Adhesion and external signals
In simple terms: Signals from the cell's environment can influence how centrosomes separate.
Integrin-mediated adhesion promotes centrosome separation in early mitosis, linking extracellular cues to spindle assembly. EGF-induced centrosome separation promotes mitotic progression and cell survival, indicating that growth factor signaling can modulate this process.
Completion and spindle assembly
In simple terms: Once separated, the centrosomes form the two poles of the mitotic spindle.
After the asters move to opposite sides of the nucleus, they become the two poles of the mitotic spindle, which is essential for chromosome segregation. Cyclin B1-Cdk1 activity continues after centrosome separation to control mitotic progression, ensuring proper timing of subsequent events. Defects in this process can lead to errors in parental genome unification in mammalian embryos.
Key Genes Involved in GO:0007100 mitotic centrosome separation
The following genes and proteins are key players in mitotic centrosome separation, based on published literature.
| Gene | Major Role | Research Relevance |
|---|---|---|
| KIF11 (Eg5) | Kinesin motor driving centrosome separation | Target for mitotic inhibitors; studied in spindle assembly |
| KIF15 | Kinesin motor involved in spindle bipolarity | Compensatory motor in centrosome separation |
| CDK1 | Cyclin-dependent kinase 1; regulates mitotic entry and progression | Controls centrosome separation timing |
| CCNB1 | Cyclin B1; activates CDK1 | Regulates mitotic progression after separation |
| PPP2R2A (B55α) | PP2A regulatory subunit; collaborates with nuclear lamina | Regulates centrosome separation during mitotic entry |
| LMNA | Nuclear lamina protein | Interacts with PP2A-B55/SUR-6 for centrosome separation |
| SUR-6 | PP2A-B55 regulatory subunit (C. elegans) | Model for PP2A-B55 function in separation |
| ITGB1 | Integrin beta 1; mediates adhesion signals | Promotes centrosome separation in early mitosis |
| EGFR | Epidermal growth factor receptor | EGF-induced centrosome separation promotes mitotic progression |
| PLK1 | Polo-like kinase 1 | Regulates mitotic entry and centrosome separation |
| AURKA | Aurora kinase A | Centrosome maturation and separation |
| CEP192 | Centrosomal protein | Centriole inheritance and centrosome function |
| SAS-6 | Centriole assembly protein | Centriole duplication and inheritance |
| TPX2 | Microtubule-associated protein | Spindle assembly and aster formation |
| NUMA1 | Nuclear mitotic apparatus protein | Spindle pole organization |
| DYNC1H1 | Dynein heavy chain | Microtubule motor involved in spindle positioning |
| RANBP1 | Ran-binding protein | Regulates spindle assembly and centrosome separation |
How Is mitotic centrosome separation Regulated?
Mitotic centrosome separation is regulated by cell cycle kinases, phosphatases, and structural proteins. Cyclin B1-Cdk1 activity continues after centrosome separation to control mitotic progression. PP2A-B55/SUR-6 collaborates with the nuclear lamina to regulate centrosome separation during mitotic entry. Integrin-mediated adhesion promotes centrosome separation in early mitosis, linking extracellular signals to spindle assembly. EGF-induced centrosome separation promotes mitotic progression and cell survival, indicating growth factor signaling can modulate this process. Phase separation mechanisms may also contribute to the assembly of mitotic structures.
mitotic centrosome separation and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| KIF11 | Cancer; mitotic arrest | Knockout or point mutation in cancer cell lines |
| CCNB1 | Cancer; cell cycle dysregulation | Overexpression or knockout in HeLa cells |
| PPP2R2A | Cancer; mitotic defects | Knockout in RPE-1 cells |
| ITGB1 | Cancer; adhesion-dependent proliferation | Knockout in MCF10A cells |
| EGFR | Cancer; growth factor signaling | Overexpression in NIH/3T3 cells |
Cancer and genomic instability
Defects in mitotic centrosome separation can lead to multipolar spindles, chromosome missegregation, and aneuploidy, which are hallmarks of cancer. EGF-induced centrosome separation promotes mitotic progression and cell survival, suggesting that growth factor signaling can influence tumor cell proliferation. Targeting kinesin motors like KIF11 has been explored as an anti-cancer strategy.
Embryonic development and infertility
Errors in centrosome separation contribute to parental genome unification errors in mammalian embryos, which can lead to developmental failure or infertility. Proper centriole inheritance is essential for early embryonic divisions.
Neurodevelopmental disorders
Although direct links are less established, proteins involved in centrosome separation, such as dynein and kinesins, are implicated in neurodevelopmental processes. Further research is needed to clarify specific disease associations.
From mitotic centrosome separation-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Does loss of KIF11 block centrosome separation? | CRISPR knockout in HeLa cells |
| Does a specific point mutation in CDK1 affect separation timing? | Point mutation knock-in in RPE-1 cells |
| How does PP2A-B55/SUR-6 regulate separation? | Knock-in of tagged SUR-6 in C. elegans |
| Does overexpression of Cyclin B1 accelerate separation? | Overexpression in U2OS cells |
| What is the role of integrin signaling in separation? | Knockout of ITGB1 in MCF10A cells |
| Can phase separation drive aster formation? | In vitro reconstitution with purified proteins |
How to Study the mitotic centrosome separation Process
| Method | What It Measures | Typical Application |
|---|---|---|
| Live-cell imaging | Dynamics of centrosome separation | Quantifying separation timing and defects |
| Immunofluorescence | Spindle morphology and aster formation | Detecting multipolar spindles |
| Proteomics | Protein interactions and complexes | Identifying regulators like PP2A-B55 |
| CRISPR knockout screening | Gene requirement for separation | Discovering novel genes |
| RNA-seq | Transcriptional changes | Linking signaling to gene expression |
| Phase separation assays | Biomolecular condensate formation | Studying mitotic structure assembly |
| Embryo imaging | Genome unification errors | Assessing developmental defects |
Live-cell imaging
Live-cell imaging of fluorescently tagged centrosomal proteins (e.g., GFP-centrin) allows real-time visualization of centrosome separation dynamics. This method is essential for quantifying separation timing and defects.
Proteomics and interactomics
Mass spectrometry-based proteomics can identify protein complexes involved in centrosome separation, such as PP2A-B55/SUR-6 and nuclear lamina components. Proximity labeling can reveal dynamic interactions during mitosis.
CRISPR screening
Genome-wide CRISPR knockout screens can identify genes required for centrosome separation, using spindle morphology or separation markers as readouts. This approach is powerful for discovering novel regulators.
Transcriptomics and RNA-seq
RNA sequencing can reveal transcriptional changes in genes related to centrosome separation under different conditions, such as EGF stimulation. This helps link signaling pathways to gene expression.
How CRISPR Can Be Used to Study GO:0007100 mitotic centrosome separation
Knockout
CRISPR knockout of genes such as KIF11 or PPP2R2A can abolish centrosome separation, leading to mitotic arrest or multipolar spindles. These models are used to test gene essentiality in cell lines like HeLa or RPE-1.
Point Mutation
Point mutations in CDK1 or CCNB1 can be introduced to study specific phosphorylation sites required for centrosome separation. Such models help dissect kinase-substrate relationships.
Knock-in
Knock-in of fluorescent tags (e.g., GFP) at endogenous loci allows real-time tracking of proteins like SUR-6 or centrin during separation. This preserves native regulation.
Overexpression
Overexpression of Cyclin B1 or EGF can accelerate centrosome separation and promote mitotic progression. These models are useful for studying gain-of-function effects.
How EDITGENE Supports mitotic centrosome separation Research
Researchers studying mitotic centrosome separation-related genes often need to determine whether a candidate gene is causally involved in the process or merely correlated with it. CRISPR-based genetic models provide the gold standard for establishing causality, enabling precise knockout, point mutation, knock-in, or overexpression of target genes in relevant cell types.
Contact EDITGENE today to design your custom CRISPR model for mitotic centrosome separation research.
Frequently Asked Questions About mitotic centrosome separation
What is mitotic centrosome separation?
Mitotic centrosome separation (GO:0007100) is the process where duplicated centrosomes separate at the beginning of mitosis, with each centriole pair becoming a microtubule organizing center that nucleates an aster, and the two asters move to opposite sides of the nucleus to form the two spindle poles.
What genes are involved in mitotic centrosome separation?
Key genes include KIF11, KIF15, CDK1, CCNB1, PPP2R2A, LMNA, ITGB1, and EGFR, among others.
Why is centrosome separation important for cell division?
It ensures bipolar spindle formation and accurate chromosome segregation, preventing aneuploidy and genomic instability.
How is centrosome separation regulated?
It is regulated by Cyclin B1-Cdk1, PP2A-B55/SUR-6, nuclear lamina, integrin signaling, and kinesin motors.
What happens if centrosome separation fails?
Failure can lead to multipolar spindles, chromosome missegregation, aneuploidy, and embryonic developmental errors.
What methods are used to study centrosome separation?
Live-cell imaging, immunofluorescence, proteomics, CRISPR screening, and RNA-seq are commonly used.
Can CRISPR be used to study centrosome separation?
Yes, CRISPR knockout, point mutation, knock-in, and overexpression models are powerful tools to dissect gene function in this process.
Is centrosome separation linked to cancer?
Yes, defects in centrosome separation are associated with aneuploidy and cancer, and kinesin motors like KIF11 are anti-cancer targets.
What is the role of kinesins in centrosome separation?
The bimC family of kinesins are essential bipolar mitotic motors that drive centrosome separation.
How does EGF signaling affect centrosome separation?
EGF-induced centrosome separation promotes mitotic progression and cell survival.
Conclusion
Mitotic centrosome separation (GO:0007100) is a fundamental biological process that ensures bipolar spindle formation and accurate chromosome segregation. Its regulation involves a complex interplay of kinases, phosphatases, motors, and structural proteins, with defects linked to cancer and developmental errors. Continued research using advanced CRISPR models and imaging techniques will further illuminate the molecular mechanisms and therapeutic potential of targeting this process.
References
- 1. Boudreau V et al.. 2019. PP2A-B55/SUR-6 collaborates with the nuclear lamina for centrosome separation during mitotic entry.. Mol Biol Cell 30(7):876-886 PMID: 30840554
- 2. Mardin BR et al.. 2013. EGF-induced centrosome separation promotes mitotic progression and cell survival.. Dev Cell 25(3):229-40 PMID: 23643362
- 3. Kashina AS et al.. 1997. The bimC family of kinesins: essential bipolar mitotic motors driving centrosome separation.. Biochim Biophys Acta 1357(3):257-71 PMID: 9268050
- 4. Woodruff JB. 2018. Assembly of Mitotic Structures through Phase Separation.. J Mol Biol 430(23):4762-4772 PMID: 29751016
- 5. Wilson PG. 2008. Centriole inheritance.. Prion 2(1):9-16 PMID: 19164929
- 6. Kamranvar SA et al.. 2022. Integrin-Mediated Adhesion Promotes Centrosome Separation in Early Mitosis.. Cells 11(8) PMID: 35456039
- 7. Lindqvist A et al.. 2007. Cyclin B1-Cdk1 activation continues after centrosome separation to control mitotic progression.. PLoS Biol 5(5):e123 PMID: 17472438
- 8. Cavazza T et al.. 2021. Parental genome unification is highly error-prone in mammalian embryos.. Cell 184(11):2860-2877.e22 PMID: 33964210
