GO:0098813 nuclear chromosome segregation: Mechanism, Genes, Functions and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0098813 nuclear chromosome segregation is the biological process that organizes nuclear chromosomes into specific structures and physically separates them to two or more sets, beginning with chromosome condensation and ending with chromosome movement to the spindle poles.
• Errors in nuclear chromosome segregation produce aneuploidy, a hallmark of cancer and a major cause of human subfertility.
• The process is coordinated with nuclear envelope assembly and disassembly in metazoans, and defects in this coordination can lead to chromosome missegregation.
• Nuclear organization, including chromosome location within the nucleus, dictates segregation error frequencies.
• Nuclear m6A modification regulates satellite transcription and chromosome segregation, linking RNA modification to genome stability.
• CRISPR-based models (knockout, point mutation, knock-in, overexpression) are essential for dissecting the causal roles of genes in nuclear chromosome segregation.
Description
Nuclear chromosome segregation (GO:0098813) is a fundamental biological process that ensures the faithful distribution of genetic material during cell division. It encompasses the condensation of chromosomes, their physical separation, and their movement to the spindle poles, ultimately apportioning chromosomes to two or more daughter sets. This process is critical for maintaining genomic stability, and its dysregulation is associated with a wide range of human pathologies, including cancer and infertility. Understanding the molecular mechanisms and regulation of nuclear chromosome segregation is therefore of paramount importance for both basic research and clinical translation. Recent studies have highlighted the role of nuclear organization and chromosome positioning in determining segregation error frequencies. Moreover, the coordination between nuclear envelope dynamics and chromosome segregation is emerging as a key regulatory node in metazoans. This article provides a comprehensive overview of the definition, mechanisms, key genes, and research methods relevant to GO:0098813, with a focus on how CRISPR-based models can accelerate discovery in this field.
nuclear chromosome segregation At A Glance
| GO ID | GO:0098813 |
|---|---|
| GO term | nuclear chromosome segregation |
| Ontology | biological_process |
| Synonym | none |
| Major function | Faithful distribution of nuclear chromosomes to daughter cells |
| Definition | The process in which genetic material, in the form of nuclear chromosomes, is organized into specific structures and then physically separated and apportioned to two or more sets. |
| Related processes | Chromosome condensation, chromosome separation, spindle pole movement |
| Disease relevance | Aneuploidy, cancer, subfertility |
What Is GO:0098813?
According to the Gene Ontology, nuclear chromosome segregation (GO:0098813) is defined as the process in which genetic material, in the form of nuclear chromosomes, is organized into specific structures and then physically separated and apportioned to two or more sets. This process begins with the condensation of chromosomes, includes chromosome separation, and ends when chromosomes have completed movement to the spindle poles.
Why Is nuclear chromosome segregation Important in Cell Biology?
Nuclear chromosome segregation is essential for genomic integrity and cell viability. Errors in this process lead to aneuploidy, which is a hallmark of cancer and a leading cause of miscarriage and developmental disorders. The spatial organization of chromosomes within the nucleus directly influences segregation fidelity, and disruptions in nuclear envelope dynamics can exacerbate missegregation. Furthermore, emerging evidence links RNA modifications, such as m6A, to the regulation of chromosome segregation, revealing new layers of control. Thus, understanding the molecular players and regulatory mechanisms of nuclear chromosome segregation is critical for developing therapeutic strategies against diseases characterized by chromosomal instability.
• Maintains genomic stability by ensuring equal chromosome distribution.
• Prevents aneuploidy, a common feature of cancer cells.
• Its failure is a major cause of human subfertility and miscarriage.
• Chromosome positioning within the nucleus dictates segregation error rates.
• Coordinated with nuclear envelope assembly and disassembly.
• Regulated by nuclear m6A RNA modification.
• Involves specialized mechanisms in closed mitosis.
• Impacted by nuclear lamina structure and ubiquitination pathways.
• Relevant to somatic cell nuclear transfer (SCNT) efficiency.
• Exotic mitotic mechanisms provide evolutionary insights.
What Happens During nuclear chromosome segregation?
Chromosome Condensation
In simple terms: Chromosomes become compact and visible structures.
The process begins with the condensation of chromosomes, which involves the compaction of chromatin into discrete, manageable structures. This step is essential for preventing chromosome entanglement and facilitating their subsequent separation.
Chromosome Separation
In simple terms: Sister chromatids are pulled apart.
Following condensation, chromosomes are physically separated. This involves the resolution of sister chromatid cohesion and the attachment of chromosomes to the spindle apparatus. Proper separation ensures that each daughter cell receives a complete set of chromosomes.
Movement to Spindle Poles
In simple terms: Chromosomes are pulled to opposite ends of the cell.
The final stage of nuclear chromosome segregation is the movement of chromosomes to the spindle poles. This is driven by microtubule dynamics and motor proteins, and it concludes when chromosomes have completed their movement to the poles.
Coordination with Nuclear Envelope Dynamics
In simple terms: The nuclear envelope breaks down and reforms around the separating chromosomes.
In metazoans, nuclear chromosome segregation is tightly coordinated with nuclear envelope assembly and disassembly. This coordination ensures that chromosomes are properly enclosed in a new nuclear envelope after segregation, and defects in this process can lead to chromosome missegregation.
Regulation by Nuclear Organization
In simple terms: The position of chromosomes in the nucleus affects how accurately they are segregated.
Recent studies have shown that nuclear chromosome locations dictate segregation error frequencies. Chromosomes located near the nuclear periphery or in specific nuclear domains may be more prone to missegregation, highlighting the importance of nuclear architecture in this process.
Key Genes Involved in GO:0098813 nuclear chromosome segregation
The following genes and proteins are key players in nuclear chromosome segregation, based on published literature.
| Gene | Major Role | Research Relevance |
|---|---|---|
| TOP2A | Chromosome condensation and separation | Target for cancer therapy; knockout leads to segregation defects |
| SMC2 | Condensin complex component | Essential for chromosome condensation; mutations cause microcephaly |
| SMC4 | Condensin complex component | Required for chromosome resolution and segregation |
| SEPASE | Separase, cleaves cohesin | Critical for sister chromatid separation; dysregulation causes aneuploidy |
| ESPL1 | Separase, cleaves cohesin | Critical for sister chromatid separation; dysregulation causes aneuploidy |
| CDK1 | Cell cycle kinase | Regulates mitotic entry and chromosome segregation |
| AURKA | Aurora kinase A | Regulates spindle assembly and chromosome alignment |
| AURKB | Aurora kinase B | Regulates chromosome bi-orientation and cytokinesis |
| PLK1 | Polo-like kinase 1 | Regulates mitotic progression and chromosome segregation |
| BUB1 | Spindle assembly checkpoint | Ensures proper chromosome attachment; mutations cause aneuploidy |
| MAD2L1 | Spindle assembly checkpoint | Monitors chromosome attachment; knockdown causes missegregation |
| NDC80 | Kinetochore component | Essential for chromosome-microtubule attachment |
| NUMA1 | Nuclear mitotic apparatus protein | Organizes spindle poles; knockout causes segregation errors |
| LMNA | Nuclear lamina protein | Maintains nuclear structure; mutations cause laminopathies with segregation defects |
| DYNEIN | Microtubule motor | Drives chromosome movement and spindle positioning |
| KIF11 | Eg5 kinesin | Required for spindle bipolarity; inhibition causes monopolar spindles |
| M6A | RNA modification | Regulates satellite transcription and chromosome segregation |
| DTOPORS | Ubiquitin ligase | Regulates nuclear lamina and meiotic chromosome segregation |
How Is nuclear chromosome segregation Regulated?
Nuclear chromosome segregation is regulated by a complex network of cell cycle kinases, including CDK1, Aurora kinases, and Polo-like kinase 1, which control mitotic progression and checkpoint signaling. The spindle assembly checkpoint (SAC) monitors chromosome attachment to the spindle and delays anaphase until all chromosomes are properly bi-oriented. Recent studies have revealed that nuclear m6A RNA modification regulates satellite transcription and chromosome segregation, adding an epitranscriptomic layer of control. Additionally, ubiquitination pathways, such as those mediated by dTopors, are required for nuclear lamina structure and meiotic chromosome segregation in Drosophila. The nuclear envelope also plays a regulatory role, as its assembly and disassembly are coordinated with chromosome segregation in metazoans.
nuclear chromosome segregation and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| BUB1 | Cancer (aneuploidy) | Knockout in cancer cell lines; xenograft models |
| MAD2L1 | Cancer (aneuploidy) | Knockdown/knockout in HeLa cells; mouse models |
| AURKA | Cancer (various) | Point mutation (kinase-dead); overexpression |
| LMNA | Laminopathies | Knock-in of patient mutations in iPSCs |
| ESPL1 | Cancer, subfertility | Conditional knockout in mouse oocytes |
Cancer and Aneuploidy
Errors in nuclear chromosome segregation lead to aneuploidy, a hallmark of many cancers. Chromosome missegregation can activate oncogenes or delete tumor suppressors, driving tumorigenesis. Genes such as BUB1, MAD2L1, and AURKA are frequently dysregulated in cancers, and their expression levels correlate with patient prognosis.
Human Subfertility
Chromosome segregation errors are a major cause of human subfertility, particularly in oocytes. The high incidence of aneuploidy in human eggs is linked to altered chromosome segregation and nuclear organization. Studies on SCNT oocytes have highlighted the importance of proper segregation for reproductive success.
Laminopathies and Nuclear Envelope Disorders
Mutations in LMNA, which encodes nuclear lamina proteins, cause laminopathies that often exhibit chromosome segregation defects. The nuclear lamina is critical for maintaining nuclear architecture and coordinating chromosome segregation, and its disruption can lead to genomic instability.
From nuclear chromosome segregation-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Does gene X regulate chromosome segregation? | Knockout cell lines (e.g., HeLa, HEK293T) |
| Does a specific mutation in gene X affect segregation? | Point mutation knock-in via CRISPR |
| What is the localization of protein X during mitosis? | Tagged knock-in (e.g., GFP) in cell lines |
| Does overexpression of gene X cause aneuploidy? | Overexpression cell models |
| What are the downstream targets of gene X? | CRISPR library screening and RNA-seq |
| Does gene X interact with known segregation factors? | Co-IP and proteomics |
How to Study the nuclear chromosome segregation Process
| Method | What It Measures | Typical Application |
|---|---|---|
| Live-cell imaging | Chromosome dynamics and segregation errors | Visualizing anaphase lagging chromosomes |
| RNA-seq | Gene expression changes | Identifying pathways affected by gene knockout |
| Proteomics (Co-IP/MS) | Protein interactions | Characterizing kinetochore complexes |
| CRISPR library screening | Gene essentiality and modifiers | Discovering novel segregation regulators |
| Immunofluorescence | Protein localization and chromosome morphology | Assessing mitotic defects |
| Flow cytometry | DNA content and aneuploidy | Quantifying aneuploid cell populations |
| Western blot | Protein expression and modification | Validating knockout or overexpression |
| Chromosome spreads | Chromosome structure and cohesion | Analyzing sister chromatid cohesion |
Live-Cell Imaging
Live-cell imaging with fluorescently tagged histones or chromosomes allows real-time visualization of chromosome segregation dynamics. This method can reveal segregation errors, such as lagging chromosomes or anaphase bridges, and is often used in combination with CRISPR-engineered cell lines.
RNA Sequencing (RNA-seq)
RNA-seq measures global gene expression changes upon perturbation of candidate genes. It can identify pathways and networks affected by loss or gain of function of segregation-related genes, providing insights into regulatory mechanisms.
Proteomics and Co-Immunoprecipitation
Proteomic approaches, including co-immunoprecipitation coupled with mass spectrometry, identify protein-protein interactions and complexes involved in chromosome segregation. These methods are useful for characterizing the composition of kinetochores, condensins, and cohesins.
CRISPR Library Screening
Genome-wide CRISPR knockout or activation screens can identify genes that are essential for chromosome segregation or that modify segregation fidelity. These screens are powerful for discovering novel regulators and potential therapeutic targets.
How CRISPR Can Be Used to Study GO:0098813 nuclear chromosome segregation
Knockout
CRISPR knockout is used to completely ablate the function of a candidate gene to determine its role in nuclear chromosome segregation. For example, knockout of BUB1 or MAD2L1 leads to checkpoint defects and aneuploidy, providing direct evidence of their essential roles.
Point Mutation
Point mutation knock-in via CRISPR allows the study of specific amino acid changes that may mimic disease-associated mutations or alter protein function. This is particularly useful for dissecting the catalytic activity or regulatory phosphorylation sites of kinases like AURKA or PLK1.
Knock-in
Knock-in of tags (e.g., GFP, FLAG) or reporter genes enables the visualization and purification of proteins involved in chromosome segregation. Tagged knock-in cell lines are valuable for live-cell imaging and proteomic studies.
Overexpression
CRISPR activation (CRISPRa) or cDNA overexpression is used to study the effects of increased gene dosage on chromosome segregation. Overexpression of AURKA, for instance, can cause centrosome amplification and mitotic defects, linking it to cancer.
How EDITGENE Supports nuclear chromosome segregation Research
Researchers studying nuclear chromosome segregation-related genes often need to determine whether a candidate gene is causally involved in the process and to dissect its molecular mechanism. EDITGENE provides a comprehensive suite of CRISPR-based services to accelerate this research.
Contact EDITGENE today to design your custom CRISPR model for nuclear chromosome segregation research.
Frequently Asked Questions About nuclear chromosome segregation
What is nuclear chromosome segregation?
Nuclear chromosome segregation (GO:0098813) is the biological process in which nuclear chromosomes are organized into specific structures and then physically separated and apportioned to two or more sets, beginning with chromosome condensation and ending with chromosome movement to the spindle poles.
What genes are involved in nuclear chromosome segregation?
Key genes include TOP2A, SMC2, SMC4, ESPL1 (separase), CDK1, AURKA, AURKB, PLK1, BUB1, MAD2L1, NDC80, NUMA1, LMNA, DYNEIN, KIF11, and DTOPORS, among others.
How does nuclear chromosome segregation relate to cancer?
Errors in nuclear chromosome segregation cause aneuploidy, a hallmark of cancer. Dysregulation of genes like BUB1, MAD2L1, and AURKA is frequently observed in various cancers.
What is the role of the nuclear envelope in chromosome segregation?
The nuclear envelope is coordinated with chromosome segregation in metazoans; its assembly and disassembly are tightly regulated to ensure proper chromosome segregation.
How can CRISPR be used to study nuclear chromosome segregation?
CRISPR knockout, point mutation, knock-in, and overexpression models allow researchers to dissect the function of specific genes in chromosome segregation, identify causal variants, and discover novel regulators.
What methods are used to study nuclear chromosome segregation?
Common methods include live-cell imaging, RNA-seq, proteomics, CRISPR library screening, immunofluorescence, flow cytometry, and chromosome spreads.
What is the role of m6A modification in chromosome segregation?
Nuclear m6A modification regulates satellite transcription and chromosome segregation, linking RNA modification to genome stability.
What diseases are associated with defects in nuclear chromosome segregation?
Diseases include cancer, human subfertility, and laminopathies. Aneuploidy is a common outcome of segregation errors.
How does nuclear organization affect chromosome segregation?
Nuclear chromosome locations dictate segregation error frequencies; chromosomes positioned near the nuclear periphery may be more prone to missegregation.
What is the spindle assembly checkpoint?
The spindle assembly checkpoint is a surveillance mechanism that monitors chromosome attachment to the spindle and delays anaphase until all chromosomes are properly bi-oriented, preventing missegregation.
Conclusion
Nuclear chromosome segregation (GO:0098813) is a highly regulated process essential for genomic stability. Its dysregulation leads to aneuploidy, cancer, and subfertility. Recent advances have highlighted the importance of nuclear organization, nuclear envelope dynamics, and RNA modifications in controlling segregation fidelity. CRISPR-based models and screening approaches are powerful tools for dissecting the molecular mechanisms of this process and for identifying new therapeutic targets. EDITGENE provides comprehensive services to support research in this critical area.
References
- 1. Klaasen SJ et al.. 2022. Nuclear chromosome locations dictate segregation error frequencies.. Nature 607(7919):604-609 PMID: 35831506
- 2. Fowler KE et al.. 2019. The role of chromosome segregation and nuclear organisation in human subfertility.. Biochem Soc Trans 47(1):425-432 PMID: 30733342
- 3. Liu S et al.. 2020. The coordination of nuclear envelope assembly and chromosome segregation in metazoans.. Nucleus 11(1):35-52 PMID: 32208955
- 4. Rodríguez-Herrera N et al.. 2025. Chromosome Segregation in Closed Mitosis Under an Excess of Nuclear Envelope.. Biol Cell 117(5):e70011 PMID: 40391723
- 5. Huang C et al.. 2026. Nuclear m(6)A modification regulates satellite transcription and chromosome segregation.. Nat Chem Biol 22(6):925-937 PMID: 40404899
- 6. Binder AM et al.. 2025. Nuclear lamina structure and meiotic chromosome segregation have different requirements for dTopors-mediated ubiquitination in male Drosophila melanogaster.. Genetics 231(4) PMID: 41100696
- 7. Lloyd L. 2024. Chromosome segregation in SCNT oocytes.. Nat Rev Urol 21(6):327 PMID: 38745080
- 8. Drechsler H et al.. 2012. Exotic mitotic mechanisms.. Open Biol 2(12):120140 PMID: 23271831
