GO:0140008 histone H4 reader activity: Mechanism, Genes and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0140008 (histone H4 reader activity) is a molecular function describing proteins that specifically bind unmodified histone H4 or H4 carrying post-translational modifications such as methylation, acetylation, or phosphorylation.
• Histone H4 readers translate chemical marks on the H4 tail into downstream biological outcomes, including chromatin remodeling, transcriptional control, and metabolic gene regulation.
• Reader domains that recognize H4 marks include bromodomains, chromodomains, PHD fingers, Tudor domains, and WD40 repeats, each with distinct residue-level specificity.
• H4 reader activity is increasingly linked to cancer, fibrosis, and neural stem cell identity through mechanisms involving lactylation, acylation, and arginine methylation.
• CRISPR knockout, point-mutation, knock-in, and overexpression models are essential for testing whether a candidate H4 reader is causally involved in a phenotype.
• EDITGENE provides end-to-end CRISPR cell model and library screening services to accelerate functional dissection of histone H4 reader biology.
Description
Histone H4 reader activity (GO:0140008) is defined as the molecular function of a protein that specifically binds either unmodified histone H4 or a form of H4 modified by a post-translational modification (PTM) on a specific residue. Histones are subject to a wide range of PTMs, most commonly methylation, acetylation, and phosphorylation, and these marks must be interpreted by reader proteins to produce biological effects. GO:0140008 therefore captures the recognition step that converts the histone H4 modification state into functional outputs such as chromatin remodeling, transcriptional activation or repression, and metabolic reprogramming. Because histone H4 is one of the most heavily modified proteins in the nucleus, H4 reader activity sits at the center of epigenetic regulation. Recent work has expanded the repertoire of H4-associated marks beyond classical methylation and acetylation to include lactylation and other acylations, which are sensed by dedicated reader proteins and linked to oncogenesis and metabolic disease. For example, histone lactylation drives oncogenesis by facilitating expression of the m6A reader YTHDF2 in ocular melanoma, illustrating how H4 mark recognition can feed into RNA-level regulatory networks. Similarly, the m6A reader IGF2BP2 regulates glycolytic metabolism and mediates histone lactylation to enhance hepatic stellate cell activation and liver fibrosis. For researchers, GO:0140008 provides a precise annotation target when studying chromatin-binding proteins, designing binding assays, or interpreting CRISPR screens. Understanding which proteins read which H4 marks, and how those interactions are regulated, is essential for dissecting disease mechanisms and for developing epigenetic therapeutics.
histone H4 reader activity At A Glance
| GO ID | GO:0140008 |
|---|---|
| GO term | histone H4 reader activity |
| Ontology | molecular_function |
| Synonym | none |
| Major function | Specific binding to unmodified histone H4 or H4 modified by PTMs such as methylation, acetylation, or phosphorylation |
| Common reader domains | Bromodomains, chromodomains, PHD fingers, Tudor domains, WD40 repeats |
| Representative PTMs | Methylation, acetylation, phosphorylation, lactylation, and other acylations |
| Disease relevance | Cancer, liver fibrosis, neural stem/progenitor cell identity, metabolic reprogramming |
| Research methods | CRISPR KO/point mutation/knock-in/overexpression, binding assays, proteomics, transcriptomics |
What Is GO:0140008?
In our own words, GO:0140008 (histone H4 reader activity) is the function of a protein module or protein complex that selectively recognizes histone H4. The recognition can target unmodified H4 or H4 carrying a specific PTM, such as methylation, acetylation, or phosphorylation, on a defined residue. This binding event is non-catalytic in the sense that the reader itself does not necessarily modify the histone; instead, it recruits or stabilizes other machinery that executes downstream chromatin and transcriptional programs.
Why Is histone H4 reader activity Important in Cell Biology?
Histone H4 reader activity is important because it is the molecular bridge between the histone code and gene expression programs. Without readers, PTMs on H4 would remain silent chemical marks; readers convert them into recruitment of chromatin remodelers, transcription factors, and RNA-processing machinery. This function is critical for normal development and is frequently dysregulated in cancer, fibrosis, and stem cell disorders.
• Defines how histone H4 PTMs are interpreted into transcriptional outcomes.
• Provides mechanistic entry points for epigenetic drug discovery.
• Links metabolism-derived marks such as lactylation to oncogenesis.
• Connects chromatin reading to RNA m6A reader networks in cancer.
• Regulates neural stem/progenitor cell identity through H4R3me2a demethylation.
• Contributes to liver fibrosis via IGF2BP2-mediated glycolytic and lactylation changes.
• Enables CRISPR-based causal testing of candidate reader genes.
• Supports development of biomarkers based on H4 modification states.
• Informs combinatorial targeting of reader and writer enzymes.
• Facilitates functional genomics screens for chromatin regulators.
Molecular Mechanism of histone H4 reader activity
Recognition of unmodified histone H4
In simple terms: Some reader proteins bind histone H4 even when it has no chemical marks, acting as placeholders that sense the unmodified state.
Histone H4 reader activity includes binding to unmodified H4, which allows the cell to detect the absence of specific PTMs. This unmodified-state recognition is important because it can mark regions poised for activation or repression and can be displaced when marks are deposited. Reader domains such as WD40 repeats and certain PHD fingers can engage the H4 tail in a mark-independent manner, providing a baseline interaction that is modulated by PTMs.
Recognition of methylated histone H4
In simple terms: Methyl groups on H4 arginine or lysine residues are recognized by dedicated reader domains, which then recruit downstream machinery.
Methylation of histone H4, including asymmetric dimethylation of arginine 3 (H4R3me2a), is a key PTM read by H4 reader proteins. Mina53 demethylates H4R3me2a to regulate neural stem/progenitor cell identity, showing that the balance between writing and erasing this mark is functionally important. Chromodomains and Tudor domains are classical methyl-lysine and methyl-arginine readers that contribute to H4 reader activity.
Recognition of acetylated and acylated histone H4
In simple terms: Acetyl and other acyl groups on H4 lysines are bound by bromodomains and related modules, linking metabolism to chromatin reading.
Acetylation and other acylations, including lactylation, are common PTMs on histone H4 and are recognized by bromodomains and other reader modules. Metabolic regulation of gene expression through histone acylations means that the availability of acyl-CoA donors influences which marks are present and therefore which readers are engaged. Histone lactylation drives oncogenesis by facilitating m6A reader protein YTHDF2 expression in ocular melanoma, demonstrating that H4 acylation reading can intersect with RNA modification pathways. In early iPSC reprogramming, Dux activates a metabolism-lactylation-MET network with Brg1 acting as a histone lactylation reader, further illustrating the breadth of H4-associated reader biology.
Recognition of phosphorylated histone H4
In simple terms: Phosphate groups on H4 are recognized by specific reader modules, often in the context of DNA damage or cell cycle signaling.
Phosphorylation is one of the most common histone PTMs and can occur on histone H4 residues, where it is interpreted by reader proteins. Although the QuickGO definition of GO:0140008 explicitly includes phosphorylation as a common PTM, the precise reader domains for phosphorylated H4 are context-dependent and often overlap with modules that bind other acidic or phospho-marked histone regions. This phosphorylation-dependent reading contributes to signaling-dependent chromatin responses.
Coupling of H4 reading to downstream effector complexes
In simple terms: Once a reader binds H4, it brings along other proteins that actually change chromatin or turn genes on or off.
H4 reader activity is not an endpoint; readers scaffold effector complexes that include chromatin remodelers, histone writers and erasers, and transcription factors. For example, Brg1 acts as a histone lactylation reader during iPSC reprogramming, coupling mark recognition to metabolic and MET network activation. In liver fibrosis, IGF2BP2 regulates glycolytic metabolism and mediates histone lactylation to enhance hepatic stellate cell activation, showing how reader-dependent circuits can drive pathological cell states. Similarly, histone lactylation-driven YTHDC1 promotes hepatocellular carcinoma progression via lipid metabolism remodeling, highlighting the integration of H4-related reading with RNA and metabolic programs.
Key Genes Involved in GO:0140008 histone H4 reader activity
The following genes and proteins represent major experimental entry points for studying histone H4 reader activity (GO:0140008), based on published literature on H4 marks, reader domains, and associated disease models.
| Gene | Major Role | Research Relevance |
|---|---|---|
| YTHDF2 | m6A reader whose expression is facilitated by histone lactylation in ocular melanoma | Links H4 lactylation reading to RNA m6A and oncogenesis |
| YTHDC1 | Histone lactylation-driven factor promoting hepatocellular carcinoma progression via lipid metabolism remodeling | Connects H4 lactylation to lipid metabolism and cancer |
| IGF2BP2 | m6A reader regulating glycolytic metabolism and mediating histone lactylation in hepatic stellate cells | Model for liver fibrosis and metabolic-epigenetic crosstalk |
| Brg1 | Histone lactylation reader during early iPSC reprogramming | Links H4 lactylation reading to pluripotency and MET |
| Mina53 | Demethylates histone H4 arginine 3 asymmetric dimethylation | Regulates neural stem/progenitor cell identity via H4R3me2a |
| H4R3me2a | Asymmetric dimethylation mark on histone H4 arginine 3 | Substrate mark for reader and eraser studies |
| H3K14ub | Ubiquitin mark on H3 that drives H3K9me3 for chromatin compartmentalization | Context for cross-talk with H4 reader biology |
| H3K9me3 | Repressive mark involved in chromatin compartmentalization | Relevant to heterochromatin reader complexes |
| Bromodomain proteins | Reader modules for acetylated and acylated lysines | Core H4 reader candidates for binding assays |
| Chromodomain proteins | Reader modules for methylated lysines and arginines | Candidate H4 methyl-reader proteins |
| PHD finger proteins | Reader modules for methylated and unmodified histones | Candidate H4 reader proteins for CRISPR studies |
| Tudor domain proteins | Reader modules for methylated histones | Candidate H4 methyl-reader proteins |
| WD40 repeat proteins | Scaffold modules that can bind histones | Candidate unmodified H4 readers |
| Histone writers | Deposit PTMs on histone H4 | Upstream regulators of reader engagement |
| Histone erasers | Remove PTMs from histone H4 | Modulate reader binding by changing mark state |
| Chromatin remodelers | Effector complexes recruited by H4 readers | Downstream functional readout of reader activity |
| Transcription factors | Interpret reader-recruited chromatin states | Link H4 reading to gene expression programs |
| Metabolic enzymes | Generate acyl-CoA donors for histone acylation | Regulate substrate availability for H4 reader engagement |
How Is histone H4 reader activity Regulated?
Histone H4 reader activity is regulated at multiple levels. First, the abundance and type of PTMs on H4 are controlled by writer and eraser enzymes, which determine whether a given reader can bind. Second, metabolic state influences the availability of acyl-CoA donors such as lactate-derived acyl groups, thereby shaping the acylation landscape that readers recognize. Third, reader proteins themselves can be regulated by expression level, post-translational modification, and interaction with cofactors. In disease contexts, dysregulated reader expression or activity can amplify oncogenic and fibrotic programs, as seen with lactylation-driven YTHDF2 and YTHDC1 in cancer and IGF2BP2 in liver fibrosis. Finally, cross-talk between different histone marks, such as H3K14ub-driven H3K9me3 for chromatin compartmentalization, can indirectly influence H4 reader accessibility.
histone H4 reader activity and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| YTHDF2 | Ocular melanoma oncogenesis driven by histone lactylation | Knockout and overexpression in ocular melanoma cell lines |
| YTHDC1 | Hepatocellular carcinoma progression via lipid metabolism remodeling | Knockout in HCC cell lines with lipid profiling |
| IGF2BP2 | Liver fibrosis via glycolytic metabolism and histone lactylation | Knockout in hepatic stellate cells and fibrosis models |
| Brg1 | iPSC reprogramming and metabolism-lactylation-MET network | Knockout and tagged knock-in in iPSC reprogramming systems |
| Mina53 | Neural stem/progenitor cell identity via H4R3me2a demethylation | Knockout and point-mutation in neural stem/progenitor cells |
Histone H4 reader activity in cancer
Histone lactylation drives oncogenesis by facilitating m6A reader protein YTHDF2 expression in ocular melanoma, directly linking H4-associated acylation reading to tumor progression. In hepatocellular carcinoma, histone lactylation-driven YTHDC1 promotes progression via lipid metabolism remodeling, showing that H4-related reader circuits can reprogram metabolic pathways in tumors. These findings position H4 reader activity as a potential therapeutic node in cancers driven by epigenetic and metabolic dysregulation.
Histone H4 reader activity in liver fibrosis
The m6A reader IGF2BP2 regulates glycolytic metabolism and mediates histone lactylation to enhance hepatic stellate cell activation and liver fibrosis. This indicates that H4-associated lactylation reading contributes to fibrotic gene programs and that targeting reader-dependent metabolic-epigenetic crosstalk may be beneficial in chronic liver disease.
Histone H4 reader activity in stem cell and neural identity
Mina53 demethylates histone H4 arginine 3 asymmetric dimethylation to regulate neural stem/progenitor cell identity, demonstrating that H4 mark erasure and reading are critical for cell fate decisions. During early iPSC reprogramming, Dux activates a metabolism-lactylation-MET network with Brg1 as the histone lactylation reader, further supporting a role for H4 reader activity in pluripotency and differentiation.
Histone H4 reader activity in chromatin compartmentalization
A conserved H3K14ub-driven H3K9me3 pathway for chromatin compartmentalization provides a broader context in which histone mark recognition, including H4 reader activity, contributes to higher-order chromatin organization. Disruption of such compartmentalization can affect gene silencing and genome stability, with implications for disease.
From histone H4 reader activity-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Is a candidate H4 reader required for tumor growth? | CRISPR knockout in cancer cell lines followed by proliferation and xenograft assays |
| Does a specific reader domain bind H4 marks? | Point-mutation of the reader domain combined with binding assays |
| Can a disease-associated reader variant alter chromatin binding? | Knock-in of the variant allele in isogenic cell lines |
| Where does a reader localize in the nucleus? | Tagged knock-in with fluorescent or epitope tags for imaging |
| Does reader overexpression drive metabolic or fibrotic programs? | Overexpression in hepatic stellate cells or cancer lines with metabolic readouts |
| Which readers are essential in a disease model? | CRISPR library screening with bioinformatics analysis |
How to Study the histone H4 reader activity Process
| Method | What It Measures | Typical Application |
|---|---|---|
| Peptide pull-down | Binding of reader to unmodified or modified H4 peptides | Initial specificity screening of candidate readers |
| Isothermal titration calorimetry | Binding affinity and thermodynamics | Quantitative comparison of reader-H4 interactions |
| ChIP-seq | Genome-wide chromatin occupancy | Mapping reader localization and histone mark distribution |
| RNA-seq | Transcriptional changes after reader perturbation | Identifying downstream pathways in disease models |
| Proteomics | Protein complex composition and PTM quantification | Discovering reader-associated complexes and mark changes |
| Fluorescence microscopy | Subcellular and nuclear localization | Visualizing reader recruitment to chromatin |
| Metabolic flux assays | Glycolytic and lipid metabolic activity | Linking reader function to metabolism |
| CRISPR library screening | Essential reader genes in a phenotype | Unbiased discovery of H4 reader dependencies |
Binding and affinity assays for H4 reader activity
Biochemical assays such as isothermal titration calorimetry, surface plasmon resonance, and peptide pull-downs using unmodified or modified H4 peptides are used to measure reader binding specificity and affinity. These methods directly test the definition of GO:0140008 by determining whether a protein binds unmodified H4 or a specific PTM form.
Transcriptomics and epigenomics
RNA-seq and chromatin immunoprecipitation followed by sequencing (ChIP-seq) are used to determine how loss or gain of a reader affects gene expression and chromatin occupancy. In disease models, these approaches reveal downstream programs such as lipid metabolism remodeling in hepatocellular carcinoma or glycolytic changes in liver fibrosis.
Proteomics and interactomics
Mass spectrometry-based proteomics can identify reader-associated complexes and quantify histone PTM changes after genetic perturbation. This is particularly useful for mapping how H4 marks such as H4R3me2a are regulated by enzymes like Mina53.
Imaging and cellular assays
Fluorescence microscopy of tagged readers and histone markers allows spatial mapping of H4 reader activity within the nucleus. Cellular assays such as proliferation, migration, and metabolic flux measurements connect reader function to disease phenotypes.
How CRISPR Can Be Used to Study GO:0140008 histone H4 reader activity
Knockout
CRISPR knockout of candidate H4 reader genes is used to test loss-of-function phenotypes such as reduced proliferation, altered transcription, or impaired reprogramming. For example, knockout of Mina53 affects neural stem/progenitor cell identity through H4R3me2a demethylation, while knockout of IGF2BP2 impacts glycolytic metabolism and liver fibrosis.
Point Mutation
Point mutation of reader domains allows precise testing of residue-level binding specificity without deleting the entire protein. This is essential for confirming that a domain such as a bromodomain or chromodomain is responsible for H4 mark recognition.
Knock-in
Knock-in of tagged alleles or disease-associated variants enables localization, interaction, and functional studies in an endogenous context. Tagged knock-in of readers can be combined with imaging and proteomics to map H4 reader activity at native expression levels.
Overexpression
Overexpression of wild-type or mutant readers is used to test gain-of-function effects on chromatin state, transcription, and disease phenotypes. For example, overexpression of lactylation-related readers can enhance oncogenic or fibrotic programs in cell models.
How EDITGENE Supports histone H4 reader activity Research
Researchers studying histone H4 reader activity-related genes often need to determine whether a candidate gene is causally involved in a phenotype, which requires precise genetic models rather than correlative observations. EDITGENE provides the CRISPR tools and cell models needed to move from candidate lists to mechanistic conclusions.
Contact EDITGENE today to design your custom CRISPR model for histone H4 reader activity research.
Frequently Asked Questions About histone H4 reader activity
What is histone H4 reader activity (GO:0140008)?
It is a molecular function describing proteins that specifically bind unmodified histone H4 or H4 modified by PTMs such as methylation, acetylation, or phosphorylation.
What genes are involved in histone H4 reader activity?
Genes encoding bromodomain, chromodomain, PHD finger, Tudor domain, and WD40 repeat proteins are common candidates, along with disease-linked factors such as YTHDF2, YTHDC1, IGF2BP2, Brg1, and Mina53.
What is the definition of GO:0140008?
The QuickGO definition states that it is a histone reader that specifically binds either to an unmodified histone H4 or a form modified by a post-translational modification on a specific residue, with methylation, acetylation, and phosphorylation being the most common PTMs.
How is histone H4 reader activity studied?
Common methods include peptide pull-downs, isothermal titration calorimetry, ChIP-seq, RNA-seq, proteomics, imaging, and CRISPR-based perturbation.
Why is histone H4 reader activity important in cancer?
Histone lactylation can drive oncogenesis by facilitating YTHDF2 expression in ocular melanoma, and lactylation-driven YTHDC1 promotes hepatocellular carcinoma progression, linking H4 reader biology to tumor growth.
What diseases are linked to histone H4 reader activity?
Cancer, liver fibrosis, and neural stem/progenitor cell disorders have been linked to H4 reader and mark regulation.
What domains recognize histone H4 marks?
Bromodomains, chromodomains, PHD fingers, Tudor domains, and WD40 repeats are among the reader modules implicated in histone H4 recognition.
Can CRISPR be used to study histone H4 reader activity?
Yes, CRISPR knockout, point mutation, knock-in, and overexpression models are widely used to test causal roles of candidate H4 readers.
What is the role of lactylation in histone H4 reader activity?
Lactylation is an acylation mark on histones that can be recognized by reader proteins and is linked to oncogenesis, iPSC reprogramming, liver fibrosis, and hepatocellular carcinoma.
How does EDITGENE support histone H4 reader research?
EDITGENE provides knockout, point-mutation, knock-in, overexpression cell models, CRISPR library screening, and bioinformatics services for H4 reader studies.
Conclusion
Histone H4 reader activity (GO:0140008) is a central molecular function that translates the histone H4 modification landscape into biological outcomes. Its roles in cancer, fibrosis, stem cell identity, and chromatin compartmentalization make it a high-value target for mechanistic and therapeutic research. By combining precise CRISPR models with multi-omics readouts, researchers can move from candidate reader lists to causal disease mechanisms.
References
- 1. Yu J et al.. 2021. Histone lactylation drives oncogenesis by facilitating m(6)A reader protein YTHDF2 expression in ocular melanoma.. Genome Biol 22(1):85 PMID: 33726814
- 2. Sabari BR et al.. 2017. Metabolic regulation of gene expression through histone acylations.. Nat Rev Mol Cell Biol 18(2):90-101 PMID: 27924077
- 3. Huang Y et al.. 2025. A conserved H3K14ub-driven H3K9me3 for chromatin compartmentalization.. Nature 647(8090):786-797 PMID: 41094145
- 4. Hu X et al.. 2024. Dux activates metabolism-lactylation-MET network during early iPSC reprogramming with Brg1 as the histone lactylation reader.. Nucleic Acids Res 52(10):5529-5548 PMID: 38512058
- 5. Zhou Y et al.. 2024. The m(6)A reader IGF2BP2 regulates glycolytic metabolism and mediates histone lactylation to enhance hepatic stellate cell activation and liver fibrosis.. Cell Death Dis 15(3):189 PMID: 38443347
- 6. Chen JJ et al.. 2022. Decoding histone ubiquitylation.. Front Cell Dev Biol 10:968398 PMID: 36105353
- 7. Du W et al.. 2025. Histone lactylation-driven YTHDC1 promotes hepatocellular carcinoma progression via lipid metabolism remodeling.. Cancer Lett 611:217426 PMID: 39725144
- 8. Zhou L et al.. 2024. Mina53 demethylates histone H4 arginine 3 asymmetric dimethylation to regulate neural stem/progenitor cell identity.. Nat Commun 15(1):10227 PMID: 39587091
