GO:0016605 PML body: Components, Assembly and Research Methods, Genes, Functions and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0016605 (PML body) is a nuclear body that reacts with SP100 auto-antibodies and typically appears 10-30 times per nucleus.
• PML bodies are dynamic, membrane-less organelles assembled through PML oligomerization and multiple partner interactions.
• They regulate apoptosis, senescence, viral defense, and telomere maintenance, and are disrupted in acute promyelocytic leukemia.
• The PML-RARA oncoprotein is the target of arsenic trioxide, which induces PML body assembly and degradation of the fusion protein.
• PML bodies are implicated in viral infections, including HSV-1 quiescence, and in ALT cancer telomere biology.
• CRISPR knockout, knock-in, and overexpression models are essential to dissect PML body gene function and therapeutic targeting.
Description
PML bodies (GO:0016605) are nuclear structures that were originally identified as autoantigens in patients with primary biliary cirrhosis and acute promyelocytic leukemia (APL). They are defined as a class of nuclear body that reacts against SP100 auto-antibodies, with cells typically containing 10-30 PML bodies per nucleus, and their localization is altered after viral infection. These membrane-less organelles are enriched in the promyelocytic leukemia protein (PML) and numerous partner proteins, serving as hubs for post-translational modifications, protein degradation, and stress responses. Research on PML bodies has grown because they are central to key cellular processes such as apoptosis, senescence, DNA repair, and antiviral defense. Their dysfunction is directly linked to APL, where the PML-RARA fusion disrupts PML body structure, and to other cancers and viral infections. Understanding PML body biogenesis and function requires integrated structural, biochemical, and genetic approaches. This article provides a research-grade overview of GO:0016605, covering its definition, composition, molecular mechanisms, disease relevance, and the CRISPR-based models used to study it. All statements are grounded in published literature to support both human readers and AI-driven retrieval systems.
PML body At A Glance
| GO ID | GO:0016605 |
|---|---|
| GO term | PML body |
| Ontology | cellular_component |
| Synonym | ND10, nuclear dot, PML NB, PML nuclear body |
| Major function | Nuclear hub for apoptosis regulation, senescence, viral defense, and telomere maintenance |
| Definition | A class of nuclear body that reacts against SP100 auto-antibodies; cells typically contain 10-30 PML bodies per nucleus; localization altered after viral infection |
| Cellular location | Nucleus |
| Typical number per cell | 10-30 per nucleus |
| Key marker | PML protein (promyelocytic leukemia protein) |
What Is GO:0016605?
GO:0016605 (PML body) is a cellular component defined as a class of nuclear body that reacts against SP100 auto-antibodies, with cells typically containing 10-30 PML bodies per nucleus, and alterations in PML body localization occur after viral infection. Synonyms include ND10, nuclear dot, PML NB, and PML nuclear body. These structures are dynamic, membrane-less organelles that assemble through PML oligomerization and interactions with partner proteins, and they function in processes such as apoptosis, senescence, and viral restriction.
Why Is PML body Important in Cell Biology?
PML bodies are important because they integrate stress signals, regulate apoptosis and senescence, and act as antiviral defense platforms. Their disruption by the PML-RARA oncoprotein is a hallmark of acute promyelocytic leukemia, and arsenic trioxide targets PML-RARA by promoting PML body assembly and degradation of the fusion protein. Furthermore, PML bodies are involved in alternative lengthening of telomeres (ALT) in cancer cells and in silencing of quiescent viral genomes, making them attractive targets for cancer and antiviral therapies.
• PML bodies regulate apoptosis through sequestration and modification of key apoptotic regulators.
• They are disrupted in acute promyelocytic leukemia by the PML-RARA fusion, which is targeted by arsenic trioxide.
• PML bodies play a role in cellular senescence and aging.
• They contribute to antiviral defense, including silencing of HSV-1 quiescent genomes via the HUSH complex.
• PML bodies are linked to alternative lengthening of telomeres (ALT) in cancer.
• They serve as platforms for post-translational modifications such as SUMOylation and ubiquitination.
• PML body biogenesis is driven by PML oligomerization and partner interactions, offering targets for therapeutic intervention.
• Alterations in PML body localization occur after viral infection, making them sensors of cellular stress.
• PML bodies are implicated in DNA repair and genome stability.
• They are studied using advanced imaging, proteomics, and CRISPR-based models.
Structure and Composition of PML body
PML protein scaffold and oligomerization
In simple terms: PML protein molecules stick together to form the core of the PML body.
PML bodies are assembled through oligomerization of the PML protein, which is driven by its N-terminal RBCC (RING, B-box, coiled-coil) domain. This oligomerization creates a scaffold that recruits partner proteins. Structural studies have revealed that PML oligomerization is regulated by a cysteine rheostat, and arsenic binding to PML cysteines promotes oligomerization and PML body assembly. The PML-RARA fusion protein disrupts normal PML oligomerization, leading to disorganized PML bodies in APL.
Partner proteins and SUMOylation
In simple terms: Many other proteins join the PML scaffold, and a tag called SUMO helps them interact.
PML bodies contain numerous partner proteins, including SP100, Daxx, and SUMOylated proteins. SUMOylation of PML and its partners is critical for PML body integrity and function. The interaction network is dynamic and regulated by post-translational modifications, allowing PML bodies to respond to stress.
Nuclear body dynamics and number
In simple terms: PML bodies can change in number and size depending on the cell's condition.
Cells typically contain 10-30 PML bodies per nucleus, but their number and size vary with cell cycle, stress, and viral infection. Viral infection often alters PML body localization and composition, as seen with HSV-1, where the HUSH complex silences viral genomes associated with PML bodies. Live-cell imaging has shown that PML bodies are dynamic structures that exchange components with the nucleoplasm.
Functional domains and interaction motifs
In simple terms: Specific parts of PML and its partners allow them to bind each other and to DNA or RNA.
The RBCC domain of PML mediates oligomerization, while the C-terminal region contains a nuclear localization signal and a SUMO-interacting motif (SIM). These domains enable PML to interact with SUMOylated proteins and to recruit factors involved in apoptosis, senescence, and DNA repair. Mutations in these domains can disrupt PML body formation and function.
Key Genes Involved in GO:0016605 PML body
The following genes and proteins are key components or regulators of PML bodies (GO:0016605) and are frequently studied in this context.
| Gene | Major Role | Research Relevance |
|---|---|---|
| PML | Scaffold protein of PML bodies; oligomerizes to form the core | Central to PML body biogenesis; mutated in APL; target of arsenic trioxide |
| SP100 | Major partner protein; autoantigen in primary biliary cirrhosis | Used as a marker for PML bodies; involved in transcriptional repression |
| DAXX | Partner protein; chromatin remodeler | Regulates apoptosis and transcription; interacts with PML |
| SUMO1/2/3 | Post-translational modifiers | SUMOylation regulates PML body assembly and partner recruitment |
| RARA | Retinoic acid receptor alpha; fusion partner of PML in APL | PML-RARA fusion disrupts PML bodies; target of ATRA and arsenic |
| HUSH complex (TASOR, MPP8, PPHLN1) | Epigenetic repressor complex | Silences HSV-1 quiescent genomes associated with PML bodies |
| TP53 | Tumor suppressor; apoptosis regulator | Interacts with PML bodies; modulates apoptosis |
| MDM2 | E3 ubiquitin ligase; p53 regulator | Sequestrated in PML bodies; affects p53 stability |
| SENP1/2 | SUMO proteases | Regulate SUMOylation balance and PML body dynamics |
| UBC9 (UBE2I) | SUMO-conjugating enzyme | Required for SUMOylation of PML and partners |
| RNF4 | SUMO-targeted ubiquitin ligase | Degrades SUMOylated PML-RARA; involved in arsenic response |
| ATRX | Chromatin remodeler; telomere maintenance | Associated with ALT telomeres and PML bodies |
| TERF1/2 | Telomere-binding proteins | Link PML bodies to telomere maintenance in ALT |
| BLM | RecQ helicase; genome stability | Localizes to PML bodies; involved in DNA repair |
| CBP/p300 | Histone acetyltransferases | Regulate PML acetylation and function |
| HIPK2 | Serine/threonine kinase | Phosphorylates PML; modulates apoptosis |
| PIN1 | Peptidyl-prolyl isomerase | Regulates PML stability and PML body formation |
| Caspase-8 | Apoptotic protease | Recruited to PML bodies during apoptosis |
How Is PML body Regulated?
PML body assembly and function are regulated by several mechanisms. SUMOylation of PML and its partners is a key regulatory step, controlled by SUMO-conjugating enzymes (UBC9) and SUMO proteases (SENP1/2). Arsenic trioxide directly binds to PML cysteines, promoting oligomerization and PML body assembly, which leads to degradation of PML-RARA. Phosphorylation by kinases such as HIPK2 and acetylation by CBP/p300 also modulate PML body dynamics. Additionally, viral infections can alter PML body localization and composition, as seen with HSV-1 and the HUSH complex.
PML body and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| PML-RARA | Acute promyelocytic leukemia | Knock-in of PML-RARA fusion in hematopoietic stem cells; ATRA/arsenic treatment |
| PML | APL, viral defense, senescence | PML knockout cell lines; viral infection models |
| HUSH complex | HSV-1 quiescence | Knockout of TASOR/MPP8 in neuronal cells; HSV-1 latency models |
| ATRX | ALT cancer | ATRX knockout in ALT cell lines; telomere imaging |
| TP53 | Cancer, apoptosis | TP53 knockout and PML body imaging under stress |
Acute promyelocytic leukemia (APL)
APL is characterized by the t(15;17) translocation that generates the PML-RARA fusion protein, which disrupts PML body structure and blocks myeloid differentiation. Arsenic trioxide targets PML-RARA by binding to PML cysteines, inducing PML body assembly and degradation of the fusion protein, leading to clinical remission. This makes PML bodies a direct therapeutic target in APL.
Viral infections
PML bodies are involved in antiviral defense. For example, the HUSH epigenetic repressor complex silences HSV-1 quiescent genomes associated with PML bodies, and viral infection alters PML body localization. PML bodies also restrict other viruses by sequestering viral proteins and promoting interferon responses.
Cancer and alternative lengthening of telomeres (ALT)
PML bodies are associated with ALT telomeres in certain cancers, where they contribute to telomere maintenance and recombination. This links PML bodies to cancer cell immortality and makes them potential targets for ALT-positive tumors.
Neurodegeneration and aging
PML bodies regulate senescence and apoptosis, processes implicated in aging and neurodegeneration. Dysregulation of PML body function may contribute to age-related cellular decline, although direct evidence in neurodegeneration is still emerging.
From PML body-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Does PML loss disrupt PML body formation? | PML knockout cell line (e.g., HeLa, U2OS) |
| How does PML-RARA affect PML body structure? | Knock-in of PML-RARA in myeloid cells |
| Does a point mutation in PML cysteine affect arsenic response? | Point-mutation knock-in of PML C212/213A |
| Where does a partner protein localize within PML bodies? | Tagged knock-in of SP100 or DAXX with GFP |
| Does overexpression of PML enhance antiviral defense? | Overexpression of PML in permissive cells followed by viral infection |
| What genes regulate PML body number? | CRISPR library screening with imaging-based readout |
How to Study the PML body Process
| Method | What It Measures | Typical Application |
|---|---|---|
| Immunofluorescence | Number and localization of PML bodies | Diagnosis of APL; viral infection studies |
| Live-cell imaging | Dynamics of PML body assembly | Real-time tracking of PML oligomerization |
| Affinity purification-MS | Protein composition of PML bodies | Identifying novel partners |
| RNA-seq | Transcriptional changes | PML body disruption effects |
| ChIP-seq | Chromatin binding of PML partners | Viral genome silencing |
| CRISPR knockout screens | Genes required for PML body formation | Functional genomics |
| Proximity labeling | Interactome in living cells | Mapping dynamic interactions |
| FRAP | Protein turnover in PML bodies | Measuring exchange rates |
Imaging and immunofluorescence
PML bodies are commonly visualized by immunofluorescence using antibodies against PML or SP100, revealing 10-30 dots per nucleus. Live-cell imaging with fluorescently tagged PML allows tracking of PML body dynamics and assembly.
Proteomics and interactomics
Affinity purification coupled with mass spectrometry has identified numerous PML body components, including SP100, Daxx, and SUMOylated proteins. Proximity labeling approaches can map the PML body interactome in living cells.
Genomic and transcriptomic profiling
RNA-seq and ChIP-seq are used to study transcriptional changes upon PML body disruption or viral infection. These methods help link PML bodies to gene regulation and antiviral responses.
CRISPR-based functional screens
CRISPR knockout libraries combined with imaging or survival readouts can identify genes that regulate PML body formation and function. Such screens have revealed roles for SUMOylation and ubiquitination pathways.
How CRISPR Can Be Used to Study GO:0016605 PML body
Knockout
CRISPR knockout of PML or its partners (e.g., SP100, DAXX) is used to study PML body formation and function. PML knockout cells lack PML bodies and show defects in apoptosis and antiviral defense. Knockout of HUSH complex components disrupts silencing of HSV-1 quiescent genomes.
Point Mutation
Point mutations in PML cysteine residues (e.g., C212A, C213A) can be introduced by CRISPR to study arsenic binding and PML oligomerization. Such models help dissect the cysteine rheostat controlling PML body assembly.
Knock-in
Knock-in of tagged PML (e.g., GFP-PML) allows live-cell imaging of PML bodies. Knock-in of the PML-RARA fusion in hematopoietic cells models APL and enables drug testing.
Overexpression
Overexpression of PML or its partners can enhance PML body formation and antiviral defense. Inducible overexpression systems allow controlled studies of PML body dynamics.
How EDITGENE Supports PML body Research
Researchers studying PML body-related genes often need to determine whether a candidate gene is causally involved in PML body assembly, function, or disease. EDITGENE provides CRISPR-based cell model services to enable such causal studies with high precision and reproducibility.
Contact EDITGENE today to design your custom CRISPR model for PML body research.
Frequently Asked Questions About PML body
What is a PML body?
A PML body (GO:0016605) is a nuclear body that reacts with SP100 auto-antibodies, typically present 10-30 times per nucleus, and its localization changes after viral infection.
What genes are involved in PML body formation?
Key genes include PML, SP100, DAXX, SUMO1/2/3, and HUSH complex components such as TASOR and MPP8.
What is the function of PML bodies?
PML bodies regulate apoptosis, senescence, antiviral defense, and telomere maintenance.
How are PML bodies linked to leukemia?
The PML-RARA fusion in APL disrupts PML bodies, and arsenic trioxide targets PML-RARA by promoting PML body assembly and degradation.
What diseases are associated with PML bodies?
Acute promyelocytic leukemia, viral infections, and ALT cancers are associated with PML body dysfunction.
How can I study PML bodies in the lab?
Common methods include immunofluorescence, live-cell imaging, proteomics, and CRISPR knockout screens.
What is the difference between PML bodies and ND10?
ND10 is a synonym for PML bodies; both refer to the same nuclear structure.
Can CRISPR be used to study PML bodies?
Yes, CRISPR knockout, knock-in, and point mutation models are widely used to dissect PML body gene function.
What is the role of SUMOylation in PML bodies?
SUMOylation regulates PML body assembly and partner recruitment, and is essential for their function.
How many PML bodies are in a cell?
Cells typically contain 10-30 PML bodies per nucleus.
Conclusion
PML bodies (GO:0016605) are dynamic nuclear organelles that play critical roles in apoptosis, senescence, antiviral defense, and telomere maintenance. Their dysfunction is directly linked to acute promyelocytic leukemia and viral infections, making them important therapeutic targets. CRISPR-based models are indispensable for dissecting the molecular mechanisms of PML body biogenesis and function. EDITGENE offers comprehensive CRISPR services, including knockout, point mutation, knock-in, overexpression, and library screening, to support research on PML bodies and related genes. By combining precise genome editing with bioinformatics, we help researchers uncover causal relationships and accelerate discoveries in this field.
References
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- 2. Li Y et al.. 2020. PML Nuclear Body Biogenesis, Carcinogenesis, and Targeted Therapy.. Trends Cancer 6(10):889-906 PMID: 32527650
- 3. Li Y et al.. 2020. PML nuclear body biogenesis and oligomerization-driven leukemogenesis.. Blood Sci 2(1):7-10 PMID: 35399865
- 4. Roubille S et al.. 2024. The HUSH epigenetic repressor complex silences PML nuclear body-associated HSV-1 quiescent genomes.. Proc Natl Acad Sci U S A 121(49):e2412258121 PMID: 39589886
- 5. Hofmann TG et al.. 2003. Body language: the function of PML nuclear bodies in apoptosis regulation.. Cell Death Differ 10(12):1290-9 PMID: 12934066
- 6. Chung I et al.. 2012. PML body meets telomere: the beginning of an ALTernate ending?. Nucleus 3(3):263-75 PMID: 22572954
- 7. Bercier P et al.. 2023. Structural Basis of PML-RARA Oncoprotein Targeting by Arsenic Unravels a Cysteine Rheostat Controlling PML Body Assembly and Function.. Cancer Discov 13(12):2548-2565 PMID: 37655965
- 8. Lallemand-Breitenbach V et al.. 2010. PML nuclear bodies.. Cold Spring Harb Perspect Biol 2(5):a000661 PMID: 20452955
