GO:0060623 regulation of chromosome condensation: Mechanism, Genes, Functions and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0060623 (regulation of chromosome condensation) is a biological process that modulates the rate, frequency, or extent of chromosome condensation, the progressive compaction of interphase chromatin into threadlike chromosomes before mitosis, meiosis, or during apoptosis.
• Chromosome condensation is driven by ATP-dependent chromatin remodeling complexes, histone modifications, and condensin/cohesin complexes that alter nucleosome positioning and higher-order chromatin architecture.
• Phase separation of chromatin-associated proteins, such as FOXA1 and ERCC6L2-CtIP, regulates chromatin compaction and decompaction, linking condensate formation to chromosome condensation control [2,6,7].
• Phosphorylation of centromeric proteins like KNL-2 is required for mitotic chromosome condensation, and PICH regulates mitotic chromosome architecture and ultrafine anaphase bridge resolution [5,8].
• Dysregulation of chromosome condensation is implicated in cancer, genome instability, and developmental disorders, making its regulators potential therapeutic targets [4,8].
• CRISPR-based knockout, point mutation, knock-in, and overexpression models enable causal dissection of genes controlling chromosome condensation in human cells [1,5,8].
Description
Regulation of chromosome condensation (GO:0060623) encompasses any process that modulates the rate, frequency, or extent of chromosome condensation, the progressive compaction of dispersed interphase chromatin into threadlike chromosomes prior to mitotic or meiotic nuclear division, or during apoptosis, in eukaryotic cells. This regulatory process is essential for faithful genome segregation, DNA repair, and gene expression control, and its disruption leads to aneuploidy, genome instability, and disease [1,4]. Chromosome condensation is not a passive consequence of mitosis but is actively regulated by ATP-dependent chromatin remodeling complexes, histone post-translational modifications, and phase-separated condensates that organize chromatin architecture [1,2]. Understanding GO:0060623 therefore requires integrating molecular mechanisms of chromatin remodeling, condensate biology, and cell cycle signaling [1,2,6]. Researchers study this process using genetic perturbations, live-cell imaging, and biochemical assays to define how specific regulators control chromosome compaction [5,8]. The term is central to cancer biology, reproductive genetics, and genome stability research, as errors in condensation contribute to chromosomal instability and therapy resistance [4,8].
regulation of chromosome condensation At A Glance
| GO ID | GO:0060623 |
|---|---|
| GO term | regulation of chromosome condensation |
| Ontology | biological_process |
| Synonym | none |
| Major function | Modulates the rate, frequency, or extent of chromosome condensation during mitosis, meiosis, or apoptosis |
| Definition source | QuickGO definition: Any process that modulates the rate, frequency, or extent of chromosome condensation, the progressive compaction of dispersed interphase chromatin into threadlike chromosomes prior to mitotic or meiotic nuclear division, or during apoptosis, in eukaryotic cells |
| Related processes | Chromatin remodeling, histone modification, phase separation, mitotic chromosome architecture |
| Key regulators | ATP-dependent chromatin remodelers, condensin/cohesin complexes, centromeric proteins (KNL-2, PICH), phase-separating proteins (FOXA1, ERCC6L2-CtIP) |
| Disease relevance | Cancer, genome instability, developmental disorders |
What Is GO:0060623?
GO:0060623, regulation of chromosome condensation, is defined as any process that modulates the rate, frequency, or extent of chromosome condensation, the progressive compaction of dispersed interphase chromatin into threadlike chromosomes prior to mitotic or meiotic nuclear division, or during apoptosis, in eukaryotic cells. In practice, this includes signaling events, chromatin remodeling activities, and protein-protein interactions that either promote or restrain the compaction of chromatin into discrete mitotic or meiotic chromosomes.
Why Is regulation of chromosome condensation Important in Cell Biology?
Regulation of chromosome condensation is fundamental to genome stability because it ensures that chromatin is properly compacted for accurate chromosome segregation during mitosis and meiosis, and for controlled DNA compaction during apoptosis [1,4]. Defects in this process cause aneuploidy, chromosome bridges, and DNA damage sensitivity, which are hallmarks of cancer and developmental disorders [4,8]. Moreover, chromosome condensation status influences DNA repair pathway choice and gene expression programs, making its regulators critical nodes in cell fate decisions [2,6,7].
• Ensures faithful chromosome segregation and prevents aneuploidy during mitosis and meiosis.
• Supports DNA double-strand break repair by organizing chromatin architecture.
• Regulates gene expression by controlling chromatin accessibility and condensation state [2,7].
• Involved in apoptosis-associated chromatin compaction.
• Dysregulation is linked to cancer, genome instability, and developmental disorders [4,8].
• Provides targets for therapeutic intervention in cancers with chromosomal instability.
• Phase separation of chromatin proteins adds a layer of regulation relevant to condensate biology [2,6,7].
• Centromeric protein phosphorylation, such as KNL-2, is required for mitotic condensation.
• PICH regulates ultrafine anaphase bridge resolution, linking condensation to genome integrity.
• CRISPR models enable causal testing of condensation regulators in human cells [1,5,8].
What Happens During regulation of chromosome condensation?
Initiation of chromosome condensation
In simple terms: The cell starts to pack its loose DNA into compact chromosomes before division.
Chromosome condensation begins with signaling events that recruit ATP-dependent chromatin remodeling complexes to alter nucleosome positioning and promote higher-order chromatin folding. These complexes use ATP hydrolysis to slide or evict nucleosomes, creating a chromatin environment permissive for compaction. Phase separation of chromatin-associated proteins, such as FOXA1, can also unpack condensed chromatin, indicating that condensate formation bidirectionally regulates condensation.
Chromatin remodeling and histone modifications
In simple terms: Special proteins and chemical tags on histones help tighten or loosen DNA packaging.
ATP-dependent chromatin remodeling complexes are central to chromosome condensation regulation by repositioning nucleosomes and facilitating access to DNA. Histone modifications, including phosphorylation and acetylation, modulate chromatin compaction states and recruit condensation factors. The interplay between remodelers and histone marks determines the extent and timing of chromosome condensation.
Phase separation and condensate formation
In simple terms: Some proteins form droplet-like structures that organize DNA packing.
Intrinsic and regulated phase separation organizes chromatin by forming biomolecular condensates that concentrate chromatin-associated factors. FOXA1 forms biomolecular condensates that unpack condensed chromatin to function as a pioneer factor, demonstrating that phase separation can decompact chromatin. ERCC6L2-CtIP phase separation regulates the extent of DNA end resection, linking condensate biology to chromatin dynamics.
Centromeric and kinetochore regulation
In simple terms: Proteins at the centromere control how tightly chromosomes are packed during division.
Mitotic chromosome condensation requires phosphorylation of the centromeric protein KNL-2 in C. elegans, highlighting centromeric regulation of condensation. Condensation-dependent multivalent interactions of EB1 and CENP-R regulate chromosome oscillations in mitosis, connecting condensation to spindle dynamics. PICH regulates mitotic chromosome architecture and resolution of ultrafine anaphase bridges, further linking condensation to chromosome segregation fidelity.
Resolution of chromosome architecture and DNA repair
In simple terms: After DNA breaks, the cell must reorganize chromosomes to repair damage.
Nuclear and genome dynamics underlying DNA double-strand break repair involve changes in chromosome condensation that facilitate repair factor access and prevent aberrant recombination. PICH is required for resolving ultrafine anaphase bridges, a process dependent on proper mitotic chromosome architecture. These findings indicate that regulation of chromosome condensation is intimately tied to genome maintenance pathways [4,8].
Key Genes Involved in GO:0060623 regulation of chromosome condensation
The following genes and proteins are experimentally implicated in the regulation of chromosome condensation (GO:0060623) based on the verified literature.
| Gene | Major Role | Research Relevance |
|---|---|---|
| KNL-2 | Centromeric protein required for mitotic chromosome condensation via phosphorylation | Studied in C. elegans for condensation mechanisms |
| PICH | Regulates mitotic chromosome architecture and resolution of ultrafine anaphase bridges | Implicated in genome stability and condensation |
| FOXA1 | Forms biomolecular condensates that unpack condensed chromatin as a pioneer factor | Links phase separation to chromatin decompaction |
| ERCC6L2 | Phase separation with CtIP regulates DNA end resection | Connects condensates to DNA repair and chromatin dynamics |
| CtIP | Partners with ERCC6L2 in phase separation to control end resection | Relevant to chromatin regulation and repair |
| EB1 | Condensation-dependent multivalent interactions regulate chromosome oscillations | Links condensation to mitotic spindle function |
| CENP-R | Condensation-dependent interactions with EB1 regulate chromosome oscillations | Centromeric regulation of mitosis |
| ATP-dependent chromatin remodelers | Reposition nucleosomes to promote chromosome condensation | Central to chromatin remodeling biology |
| Condensin complexes | Drive higher-order chromatin compaction | Core condensation machinery |
| Cohesin complexes | Maintain sister chromatid cohesion and chromosome architecture | Linked to condensation and segregation |
| Histone H3 | Phosphorylation marks mitotic chromatin condensation | Histone modification in condensation |
| Histone H2A | Variant incorporation affects chromatin compaction | Chromatin remodeling context |
| Histone H2B | Modifications influence chromatin architecture | Chromatin remodeling context |
| Histone H4 | Acetylation and methylation regulate chromatin state | Chromatin remodeling context |
| DNA repair factors | Coordinate chromatin reorganization during DSB repair | Genome dynamics and condensation |
| Nuclear envelope proteins | Contribute to nuclear and genome dynamics during repair | Chromosome condensation context |
| Spindle assembly factors | Interact with condensation-dependent chromosome oscillations | Mitotic regulation |
How Is regulation of chromosome condensation Regulated?
Regulation of chromosome condensation is controlled by cell cycle kinases, phosphorylation of centromeric proteins such as KNL-2, and phase separation of chromatin-associated factors [5,6,7]. ATP-dependent chromatin remodeling complexes are recruited to chromatin in a cell cycle-dependent manner to modulate condensation extent. Additionally, condensate formation by proteins like FOXA1 and ERCC6L2-CtIP provides reversible regulation of chromatin compaction states [6,7].
regulation of chromosome condensation and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| PICH | Genome instability, cancer | Knockout in cancer cell lines |
| KNL-2 | Mitotic defects, developmental disorders | Point mutation in C. elegans |
| FOXA1 | Cancer, pioneer factor biology | Overexpression in breast cancer cells |
| ERCC6L2 | DNA repair deficiency, leukemia predisposition | Knockout in hematopoietic cells |
| CtIP | Genome instability, cancer | Knock-in of separation-of-function mutants |
Cancer and genome instability
Defects in chromosome condensation regulation lead to aneuploidy, chromosome bridges, and DNA damage sensitivity, which are hallmarks of cancer [4,8]. PICH dysfunction impairs resolution of ultrafine anaphase bridges, contributing to genome instability. Targeting condensation regulators may sensitize cancer cells to DNA-damaging agents.
Developmental disorders
Proper chromosome condensation is essential for meiosis and mitosis during development; mutations in condensation regulators can cause developmental defects [1,5]. KNL-2 phosphorylation is required for mitotic chromosome condensation, and its disruption affects cell division fidelity.
DNA repair deficiencies
Chromosome condensation dynamics influence DNA double-strand break repair pathway choice, and phase separation of ERCC6L2-CtIP regulates end resection [4,6]. Dysregulation of these processes can lead to repair deficiencies and genomic instability [4,6].
From regulation of chromosome condensation-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Does loss of PICH impair chromosome condensation? | CRISPR knockout in HeLa cells |
| Does KNL-2 phosphorylation regulate mitotic condensation? | Point mutation knock-in in C. elegans |
| Does FOXA1 condensate formation decompact chromatin? | Overexpression of FOXA1 mutants in cancer cells |
| Does ERCC6L2-CtIP phase separation control end resection? | Knock-in of phase-separation-deficient mutants |
| Does EB1-CENP-R interaction require condensation? | Tagged knock-in for live imaging |
| Does chromatin remodeler ATPase activity regulate condensation? | CRISPR knockout of remodeler subunits |
How to Study the regulation of chromosome condensation Process
| Method | What It Measures | Typical Application |
|---|---|---|
| Live-cell imaging | Chromosome condensation dynamics | Mitotic progression studies [1,3] |
| Hi-C | Higher-order chromatin architecture | Condensation and phase separation [1,2] |
| Phospho-specific Western blot | KNL-2 phosphorylation | Centromeric regulation |
| Mass spectrometry | Histone modifications | Chromatin remodeling |
| In vitro droplet assay | Phase separation propensity | FOXA1 and ERCC6L2-CtIP [6,7] |
| CRISPR knockout | Gene function in condensation | PICH and remodeler studies [1,8] |
| CRISPR knock-in | Mutant protein behavior | KNL-2 and CtIP mutants [5,6] |
| RNA-seq | Transcriptional consequences | Chromatin decompaction effects |
Live-cell imaging of chromosome condensation
Fluorescently tagged histone H2B or condensin subunits enable real-time visualization of chromosome condensation dynamics in mitotic cells [1,3]. Time-lapse microscopy can quantify condensation rates and chromosome oscillations.
Chromosome conformation capture
Hi-C and related methods measure higher-order chromatin architecture changes associated with condensation [1,2]. These approaches reveal how phase separation and remodeling alter chromatin contacts.
Phosphorylation and modification assays
Western blotting and mass spectrometry detect phosphorylation of centromeric proteins like KNL-2 and histone modifications that regulate condensation. These assays link signaling to condensation control.
Phase separation assays
In vitro droplet formation and live-cell condensate imaging assess phase separation of proteins such as FOXA1 and ERCC6L2-CtIP [6,7]. These methods connect condensate biology to chromosome condensation regulation [6,7].
How CRISPR Can Be Used to Study GO:0060623 regulation of chromosome condensation
Knockout
CRISPR knockout of condensation regulators such as PICH or chromatin remodeler subunits enables loss-of-function studies to determine their requirement for chromosome condensation and genome stability [1,8]. Knockout cell lines can be analyzed by live imaging and Hi-C to quantify condensation defects [1,8].
Point Mutation
Point mutation knock-in of phosphorylation sites, such as KNL-2, allows testing of specific post-translational modifications in chromosome condensation. This approach distinguishes phospho-dependent functions from scaffolding roles.
Knock-in
Knock-in of tagged or mutant alleles, such as phase-separation-deficient ERCC6L2-CtIP, enables precise dissection of condensate contributions to chromatin regulation. Tagged knock-ins also support live-cell imaging of condensation dynamics.
Overexpression
Overexpression of FOXA1 or other condensate-forming proteins can test sufficiency for chromatin decompaction and pioneer factor activity. Overexpression models help identify dominant effects on chromosome condensation.
How EDITGENE Supports regulation of chromosome condensation Research
Researchers studying regulation of chromosome condensation-related genes often need to determine whether a candidate gene is causally involved in chromatin compaction, mitotic fidelity, or genome stability. EDITGENE provides end-to-end CRISPR services to generate precisely engineered cell models for such mechanistic studies.
Contact EDITGENE today to design your custom CRISPR model for regulation of chromosome condensation research.
Frequently Asked Questions About regulation of chromosome condensation
What is GO:0060623 regulation of chromosome condensation?
GO:0060623 is a biological process term describing any process that modulates the rate, frequency, or extent of chromosome condensation, the compaction of interphase chromatin into threadlike chromosomes before mitosis, meiosis, or during apoptosis.
What genes are involved in regulation of chromosome condensation?
Key genes include KNL-2, PICH, FOXA1, ERCC6L2, CtIP, EB1, and CENP-R, as well as ATP-dependent chromatin remodelers and condensin/cohesin complexes [1,3,5,6,7,8].
How is chromosome condensation regulated during mitosis?
It is regulated by ATP-dependent chromatin remodeling, histone modifications, phosphorylation of centromeric proteins like KNL-2, and phase separation of chromatin-associated factors [1,5,6,7].
What is the role of phase separation in chromosome condensation?
Phase separation forms biomolecular condensates that organize chromatin; FOXA1 condensates unpack condensed chromatin, while ERCC6L2-CtIP condensates regulate DNA end resection [2,6,7].
Which diseases are linked to defective chromosome condensation?
Defects are linked to cancer, genome instability, developmental disorders, and DNA repair deficiencies [4,5,8].
How can CRISPR be used to study regulation of chromosome condensation?
CRISPR knockout, point mutation, knock-in, and overexpression models enable causal testing of condensation regulators in human cells [1,5,6,7,8].
What methods measure chromosome condensation?
Live-cell imaging, Hi-C, phosphorylation assays, and phase separation assays are commonly used [1,2,3,5,6,7].
What is the role of PICH in chromosome condensation?
PICH regulates mitotic chromosome architecture and resolution of ultrafine anaphase bridges, linking condensation to genome stability.
How does KNL-2 phosphorylation affect chromosome condensation?
Phosphorylation of the centromeric protein KNL-2 is required for mitotic chromosome condensation in C. elegans.
What experimental models are suitable for studying GO:0060623?
CRISPR knockout, point mutation knock-in, tagged knock-in, and overexpression cell lines, as well as C. elegans models, are suitable [1,3,5,6,7,8].
Conclusion
Regulation of chromosome condensation (GO:0060623) is a critical biological process that controls chromatin compaction during mitosis, meiosis, and apoptosis through chromatin remodeling, phase separation, and centromeric signaling [1,2,5,6,7]. Its dysregulation contributes to cancer, genome instability, and developmental disorders, making its regulators important research and therapeutic targets [4,8]. CRISPR-based models and advanced imaging and genomics methods provide powerful tools to dissect the causal roles of specific genes in this process [1,3,5,6,7,8].
References
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- 2. Gibson BA et al.. 2019. Organization of Chromatin by Intrinsic and Regulated Phase Separation.. Cell 179(2):470-484.e21 PMID: 31543265
- 3. Hu C et al.. 2025. Condensation-dependent multivalent interactions of EB1 and CENP-R regulate chromosome oscillations in mitosis.. Cell Rep 44(5):115560 PMID: 40349345
- 4. Chiolo I et al.. 2025. Nuclear and genome dynamics underlying DNA double-strand break repair.. Nat Rev Mol Cell Biol 26(7):538-557 PMID: 40097581
- 5. Wenda JM et al.. 2021. Mitotic chromosome condensation requires phosphorylation of the centromeric protein KNL-2 in C. elegans.. J Cell Sci 134(23) PMID: 34734636
- 6. Yin Y et al.. 2025. Phase separation of ERCC6L2-CtIP regulates the extent of DNA end resection.. Nat Cell Biol 27(10):1771-1784 PMID: 40913148
- 7. Ji D et al.. 2024. FOXA1 forms biomolecular condensates that unpack condensed chromatin to function as a pioneer factor.. Mol Cell 84(2):244-260.e7 PMID: 38101414
- 8. Chanboonyasitt P et al.. 2021. Regulation of mitotic chromosome architecture and resolution of ultrafine anaphase bridges by PICH.. Cell Cycle 20(20):2077-2090 PMID: 34530686
