Functional annotation report: equine DNMT3A candidate A0A9L0TK01 Falcon Edison Scientific Literature 34 citations 1 artifacts 2026-09-08T14:16:19.477112

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Functional annotation report: equine DNMT3A candidate A0A9L0TK01

Executive conclusion

Identity verification: The supplied UniProt accession A0A9L0TK01 is assigned to Equus caballus and annotated as DNA (cytosine-5)-methyltransferase, EC 2.1.1.37. Its ADD/ADD_DNMT3A and C5-DNA-methyltransferase domains are strongly consistent with a DNMT3A-family de novo DNA methyltransferase. Nevertheless, the UniProt information supplied does not itself specify the gene symbol, and no publication retrieved studied A0A9L0TK01 specifically. Thus, “equine DNMT3A” is a plausible and internally consistent functional assignment, but not an accession-specific experimental identification.

The primary predicted function is nuclear, chromatin-associated transfer of a methyl group from S-adenosyl-L-methionine (SAM) to carbon 5 of cytosine in DNA, producing 5-methylcytosine and S-adenosyl-L-homocysteine. In mammals, DNMT3A acts predominantly at CpG dinucleotides but can methylate non-CpG cytosines in selected developmental and neuronal contexts. Its genomic targeting depends less on a strict extended DNA sequence motif than on nucleosome state, histone modifications, oligomerization, and interacting proteins. These mechanistic conclusions are well established for mammalian DNMT3A but remain orthology-based predictions for A0A9L0TK01, because purified equine-protein activity, chromatin occupancy, and cellular localization have not been reported (gilbert2026targetingdnamethylation pages 3-6, gilbert2026targetingdnamethylation pages 1-3, dupas2026dnmt3aincancer pages 2-3, davletgildeeva2024theroleof pages 7-8).

1. Identification and annotation confidence

Species and gene-family verification

The target organism is correctly specified as horse, Equus caballus. The supplied protein description, EC number, class-I-like SAM-binding methyltransferase classification, ADD domain, DNMT3A-type ADD annotation, and C5-cytosine methyltransferase domains all align with DNMT3A biology. This is not evidence for a different similarly named protein.

However, two qualifications are important:

  1. The supplied UniProt record lacks an explicit gene field. Therefore, the symbol DNMT3A should be treated as an inferred mapping, not as independently confirmed solely from the metadata provided.
  2. Canonical vertebrate DNMT3A normally contains an N-terminal regulatory region, a PWWP domain, an ADD domain, and a C-terminal catalytic methyltransferase domain. The supplied domain list includes ADD and catalytic C5-methyltransferase annotations but does not list PWWP. This could reflect an incomplete predicted sequence, an isoform, or annotation sensitivity. Full sequence alignment against curated mammalian DNMT3A and verification of the catalytic motifs and PWWP region are advisable before assigning all canonical DNMT3A regulatory properties.

No retrieved publication purified A0A9L0TK01, identified it by accession-specific peptides, localized it with a validated antibody, or disrupted its gene in horse. Accordingly, this report separates direct equine evidence from conserved mammalian inference.

Claim or feature Evidence in horse Evidence type Confidence and interpretation
Protein identity: DNMT3A-like DNA cytosine-5 methyltransferase in Equus caballus The user-provided UniProt record A0A9L0TK01 assigns EC 2.1.1.37, the class-I-like SAM-binding methyltransferase family, ADD and ADD_DNMT3A domains, and C5-DNA-methyltransferase domains. The record does not specify a gene symbol. Computational database annotation Moderate. The description and domains are consistent with DNMT3A, but accession-to-gene mapping and the complete domain architecture require independent confirmation. This is not experimental validation.
DNMT3A transcript in mare endometrial fibroblasts Equine-specific qRT-PCR amplified a 206-bp product designed from horse transcript XM_023619394.1. In fibroblasts from five mares, TGF-β1 at 10 ng/mL increased DNMT3A mRNA at 48 h with p less than 0.05 and at 96 h with p less than 0.01. DNMT1 and DNMT3B did not change. Adding 1 µM 5-aza-dC after 48 h reduced TGF-β1-associated DNMT3A mRNA at 96 h with p less than 0.001 (alpoimmoreira20235aza2′deoxycytidine(5azadcdecitabine) pages 5-7, alpoimmoreira20235aza2′deoxycytidine(5azadcdecitabine) pages 7-10). Direct horse transcript measurement and pharmacological perturbation High for transcript detection and regulation; low for enzyme causality. Protein abundance, catalytic activity, genomic targets, and intracellular localization were not measured. Moreover, 5-aza-dC is not selective for DNMT3A.
DNMT3A expression in early equine conceptus membranes Gibson et al. used sequence-validated qRT-PCR on yolk-sac membranes from synchronous and negatively asynchronous day-14 and day-19 conceptuses. Available search information indicates lower DNMT3A expression with asynchrony, but the extracted results do not provide the relevant effect size or significance value (gibson2017negativeuterineasynchrony pages 6-10). Horse transcript study with incompletely extracted results Low to moderate. The methods support transcript analysis in conceptus tissue, but the complete results and figures should be checked before making a quantitative or causal claim.
DNA-methylation dynamics in equine zygotes Immunofluorescence detected 5mC and 5hmC throughout pronuclear development in ICSI-derived equine zygotes. Signals were broadly similar between parental pronuclei; maternal 5mC increased from PN1 to PN2, paternal 5mC did not change significantly, and normalized 5hmC remained stable (heras2017dynamicsof5methylcytosine pages 7-10, heras2017dynamicsof5methylcytosine pages 1-2). Direct horse epigenetic-mark measurement but indirect evidence for DNMT3A High for the observed DNA modifications; very low for attribution to DNMT3A. The study did not measure DNMT3A transcript, protein, localization, inhibition, depletion, or activity. ICSI-derived embryos may also differ from embryos produced in vivo.
DNMT3A locus and age-related methylation in horse lymphocytes Equine DNMT3A and DNMT3B loci and polymorphisms were genotyped in cultured blood lymphocytes from horses aged 4 days to 21 years, alongside analyses of global 5-methyl-2′-deoxycytidine and rDNA methylation (wnuk2014changesindna pages 6-7). Direct horse genotyping plus indirect methylome measurements Moderate for the presence of an equine DNMT3A locus; very low for protein function. Expression, protein abundance, localization, catalytic activity, and locus-specific causality were not measured.
Catalytic reaction and substrate By mammalian orthology, DNMT3A transfers a methyl group from S-adenosyl-L-methionine to cytosine C5, producing 5-methylcytosine and S-adenosyl-L-homocysteine. The mechanism involves base flipping and a transient covalent intermediate formed by a catalytic cysteine. Activity is predominantly directed toward CpG DNA, although context-dependent non-CpG methylation also occurs (gilbert2026targetingdnamethylation pages 3-6, gilbert2026targetingdnamethylation pages 1-3). Biochemical and structural evidence from non-equine mammalian DNMT3A High for conserved DNMT3A chemistry but unvalidated for A0A9L0TK01. No purified horse-protein assay has established its reaction rate, CpG preference, or flanking-sequence specificity.
Cellular site of action Mammalian DNMT3A is a nuclear, chromatin-associated de novo methyltransferase. Its regulatory domains recruit and activate it on nucleosomes, supporting a nuclear chromatin location rather than an extracellular, membrane, or primarily cytosolic role (dupas2026dnmt3aincancer pages 2-3, davletgildeeva2024theroleof pages 7-8). Mammalian orthology inference High as a likely conserved localization but not directly demonstrated in horse. No accession-specific immunofluorescence, cell fractionation, chromatin-occupancy assay, or localization proteomics was found.
Chromatin targeting by ADD, PWWP, and the N terminus Mammalian DNMT3A ADD recognizes H3K4me0 and relieves autoinhibition, whereas PWWP recognizes H3K36me2 or H3K36me3. Full-length DNMT3A1 also contacts the nucleosome through an N-terminal UDR. Apparent affinities were 376 ± 17 nM for unmodified nucleosomes, 207 ± 6.7 nM for H3K36me2 nucleosomes, 126 ± 3.6 nM for H2AK119ub nucleosomes, and 109 ± 2.5 nM for doubly modified nucleosomes. H3K36me2 stimulated methylation, whereas H2AK119ub chiefly enhanced recruitment (wapenaar2024thenterminalregion pages 10-11, wapenaar2024thenterminalregion pages 13-14, wapenaar2024thenterminalregion pages 3-4). 2024 structural and biochemical evidence from non-equine DNMT3A1 Strong mechanistic orthology inference. The supplied horse annotation confirms ADD-family and catalytic domains but does not list PWWP. The equine sequence and domain model should be checked before assigning the entire DNMT3A1 targeting mechanism to A0A9L0TK01.
Accession-specific experimental validation No retrieved study purified A0A9L0TK01, detected that exact protein through accession-specific peptides or antibodies, measured its methyltransferase activity, mapped its chromatin binding, or established its subcellular localization in horse. Evidence gap Critical limitation. The protein's function should be described as predicted or inferred from conserved domains and mammalian orthology unless A0A9L0TK01 is linked to an experimentally validated equine transcript or protein isoform.

Table: Evidence is separated into direct equine measurements, indirect horse epigenetic observations, and mammalian orthology-based inference. The table emphasizes the absence of accession-specific protein, enzymatic, and localization validation.

2. Primary biochemical function

Catalyzed reaction

The expected reaction is:

DNA cytosine + SAM → DNA 5-methylcytosine + S-adenosyl-L-homocysteine.

DNMT3A binds DNA and SAM in its C-terminal methyltransferase domain. The target cytosine is flipped out of the duplex into the active site. A conserved catalytic cysteine attacks cytosine C6, producing a transient covalent enzyme–DNA intermediate that activates carbon 5 for methyl transfer; elimination then restores the aromatic base and releases 5-methylcytosine. Mammalian DNMT3A residue C710 is identified as the catalytic cysteine in human-numbering descriptions, but the corresponding residue has not been verified in A0A9L0TK01 (gilbert2026targetingdnamethylation pages 3-6, schmelmer2026targetingdnmt3aregulatory pages 9-15, gilbert2026targetingdnamethylation pages 1-3).

Substrate specificity

The physiological substrate is chromosomal double-stranded DNA in nucleosomes, principally cytosines in CpG dinucleotides. DNMT3A is described as a de novo enzyme because it can establish methylation on previously unmethylated DNA, unlike DNMT1’s strong specialization for copying methylation onto hemimethylated daughter DNA after replication. The distinction is functional rather than absolute: DNMT3A can contribute to maintenance at selected loci, while recruitment context strongly influences activity (dupas2026dnmt3aincancer pages 2-3, davletgildeeva2024theroleof pages 5-7, gilbert2026targetingdnamethylation pages 3-6).

DNMT3A does not have a single, sharply restrictive extended-sequence consensus. Its regional specificity is substantially imposed by chromatin. Context-dependent non-CpG methylation occurs in embryonic stem cells and selected neuronal or developmental contexts but is much less characteristic of ordinary adult somatic tissues (gilbert2026targetingdnamethylation pages 1-3, davletgildeeva2024theroleof pages 5-7). No horse-specific kinetic study has measured A0A9L0TK01 preference for unmethylated versus hemimethylated DNA, CpG-flanking sequence, nucleosomal versus naked DNA, or non-CpG substrates.

Oligomerization and cofactors

Mammalian DNMT3A forms dimers, tetramers, and higher-order assemblies through its catalytic domain. Oligomerization increases cooperativity, processivity, and productive DNA engagement. The catalytically inactive DNMT3L protein stimulates DNMT3A through heteromeric assembly and chromatin recognition; DNMT3A itself supplies the catalytic chemistry (schmelmer2026targetingdnmt3aregulatory pages 9-15, schmelmer2026targetingdnmt3aregulatory pages 78-84, garcia2023baseeditorscanning pages 12-15). Whether A0A9L0TK01 forms the same complexes with equine DNMT3L has not been tested.

3. Cellular localization and chromatin targeting

The expected site of action is the cell nucleus, on chromatin and nucleosomes. DNMT3A is not predicted to be secreted, membrane-bound, or a transporter. Its localization is dynamic and determined by several chromatin-reading modules.

Importantly, chromatin recruitment and catalytic activation are not equivalent. Wapenaar et al. measured apparent dissociation constants of 376 ± 17 nM for unmodified nucleosomes, 207 ± 6.7 nM for H3K36me2 nucleosomes, 126 ± 3.6 nM for H2AK119ub nucleosomes, and 109 ± 2.5 nM for doubly modified nucleosomes. H2AK119ub strengthened recruitment but did not by itself stimulate DNA methylation, whereas H3K36me2 stimulated activity. The results support a multivalent model in which one chromatin feature can recruit DNMT3A while another controls productive catalysis (published November 2024; https://doi.org/10.1038/s44319-024-00306-3) (wapenaar2024thenterminalregion pages 10-11, wapenaar2024thenterminalregion pages 13-14).

No immunofluorescence, nuclear fractionation, chromatin immunoprecipitation, CUT&RUN, or accession-specific localization proteomics has established the intracellular location of A0A9L0TK01 in horse. Nuclear chromatin localization is therefore a strong conserved prediction, not direct equine evidence.

4. Biological processes and pathways

De novo methylome establishment

DNMT3A participates in the mammalian DNA-methylation pathway that rebuilds methylation patterns after developmental demethylation. This supports stable cell identity, regulation of promoters and enhancers, transposable-element control, genomic imprinting, and tissue-specific transcription. DNMT1 then predominantly propagates established methylation through DNA replication. DNA methylation is not uniformly repressive: its effect depends on whether it occurs at promoters, enhancers, gene bodies, repetitive DNA, or other regulatory regions (dupas2026dnmt3aincancer pages 2-3, davletgildeeva2024theroleof pages 7-8, davletgildeeva2024theroleof pages 5-7).

Germ cells, imprinting, and embryos

Mammalian evidence places DNMT3A, often together with DNMT3L, in germ-cell methylation and maternal imprint establishment. Germ-cell loss of DNMT3A disrupts spermatogenesis or parental imprinting in mouse, while DNMT3-family proteins accompany imprint acquisition in growing bovine oocytes. In bovine oocytes, transcripts and proteins for DNMT3A, DNMT3B, and DNMT3L were directly detected; two DNMT3A forms, including a lower-molecular-weight DNMT3A2-like product, were observed. These bovine results are comparative evidence, not proof for horse (odoherty2012bovinednamethylation pages 8-8, odoherty2012bovinednamethylation pages 8-9, odoherty2012bovinednamethylation pages 1-2, davletgildeeva2024theroleof pages 7-8).

Equine zygotes produced by intracytoplasmic sperm injection retained detectable 5mC and 5hmC in both parental pronuclei. Maternal 5mC increased from PN1 to PN2, paternal 5mC showed no significant change, and normalized 5hmC remained stable. This differs from the classic mouse model of rapid asymmetric paternal demethylation. However, the study measured DNA modifications—not DNMT3A expression or activity—and ICSI embryos may not fully reproduce in-vivo development (published March 2017; https://doi.org/10.1186/s13072-017-0120-x) (heras2017dynamicsof5methylcytosine pages 7-10, heras2017dynamicsof5methylcytosine pages 1-2).

Somatic differentiation and adult tissues

Mammalian DNMT3A is highly expressed in pluripotent/developing cells and remains functional in selected adult tissues, including postmitotic neurons. Its contribution to adult chromatin indicates that “de novo” does not mean embryo-only. DNMT3A2 has been linked to activity-responsive transcription in hippocampal neurons, while DNMT3A mutations affect developmental and hematopoietic programs. These are authoritative mammalian findings but have not been functionally reproduced for A0A9L0TK01 (kim2025theroleof pages 6-7, davletgildeeva2024theroleof pages 7-8).

5. Direct evidence in horse

Mare endometrial fibroblasts: strongest gene-specific evidence

A 2023 study designed equine DNMT3A qPCR primers from horse transcript XM_023619394.1, yielding a 206-bp amplicon. Primary endometrial fibroblasts from five mares were treated with 10 ng/mL TGF-β1. DNMT3A mRNA increased at 48 hours (p<0.05) and 96 hours (p<0.01), whereas DNMT1 and DNMT3B transcripts did not significantly change. Adding 1 µM 5-aza-2′-deoxycytidine after 48 hours reduced DNMT3A mRNA in TGF-β1-treated cells at 96 hours (p<0.001) (published March 2023; https://doi.org/10.3390/ani13071212) (alpoimmoreira20235aza2′deoxycytidine(5azadcdecitabine) pages 5-7, alpoimmoreira20235aza2′deoxycytidine(5azadcdecitabine) pages 7-10).

The same treatment reduced TGF-β1-induced COL1A1 and COL3A1 transcripts and secreted collagen. This suggests that DNMT-regulated epigenetic processes participate in equine endometrial fibrogenesis. It does not establish that DNMT3A directly methylates collagen genes: 5-aza-dC is a nonselective, replication-dependent DNMT-trapping agent, no DNMT3A protein or enzymatic activity was measured, and the study did not map methylation changes at collagen regulatory elements (alpoimmoreira20235aza2′deoxycytidine(5azadcdecitabine) pages 3-5, alpoimmoreira20235aza2′deoxycytidine(5azadcdecitabine) pages 7-10).

Early conceptus development

Gibson et al. performed sequence-validated qRT-PCR on yolk-sac membranes from synchronous and negatively asynchronous day-14 and day-19 equine conceptuses. The experimental design included 26 transfers, producing 10/13 pregnancies after synchronous transfer and 12/13 after asynchronous transfer, although two asynchronous conceptuses were lost during collection. Negative asynchrony markedly delayed development: day-14 vesicle diameter was 11.3 ± 0.6 versus 18.2 ± 1.1 mm, and day-19 embryonic length was 2.55 ± 0.19 versus 5.05 ± 0.23 mm. Search metadata indicate lower DNMT3A expression under asynchrony, but the extracted text did not provide the corresponding DNMT3A effect size and significance; therefore, that specific expression result should be treated cautiously (published September 2017; https://doi.org/10.1016/j.placenta.2017.07.007) (gibson2017negativeuterineasynchrony pages 6-10).

Blood lymphocytes and ageing

An equine ageing study genotyped DNMT3A/DNMT3B loci and polymorphisms in cultured blood lymphocytes from healthy horses ranging from 4 days to 21 years, alongside global 5-methyl-2′-deoxycytidine and rDNA methylation analyses. This supports the genomic presence and study of an equine DNMT3A locus, but not its expression, localization, or catalytic role in lymphocytes (published May 2014; https://doi.org/10.1007/s11357-013-9541-z) (wnuk2014changesindna pages 6-7).

Placental methylome as pathway context

A 2023 equine placental study found progressively higher global methylation toward late gestation. It identified 921 DMRs between months 4 and 6, 1,225 DMRs between months 4 and 10, and 1,026 DMRs between months 6 and 10; corresponding transcriptome comparisons identified 1,381, 1,428, and 741 differentially expressed genes. Among regions linked to both methylation and expression changes, 48.4% were intronic, 25.8% promoter-associated, and 17.7% exonic. These data demonstrate a substantial equine developmental methylome program but do not identify DNMT3A as its causal writer (published April 2023; https://doi.org/10.3390/ijms24087084).

6. Recent developments, 2023–2024

  1. Multivalent nucleosome recognition (2024): Full-length DNMT3A1 was shown to contact the nucleosome surface through its N-terminal UDR and read H2AK119ub, while PWWP engagement of H3K36me2 provided a stronger link to catalytic stimulation. This revises a simple “one domain–one histone mark” model toward integrated chromatin sensing (https://doi.org/10.1038/s44319-024-00306-3) (wapenaar2024thenterminalregion pages 10-11, wapenaar2024thenterminalregion pages 3-4).
  2. ADD-domain specialization in germ cells (2024): Kubo et al. examined the distinct and combined functions of DNMT3A and DNMT3L ADD domains in mouse germ-cell methylation landscapes, reinforcing the importance of H3-tail sensing in developmental target selection (https://doi.org/10.1038/s41467-024-47699-2) (schmelmer2026targetingdnmt3aregulatorya pages 91-93, schmelmer2026targetingdnmt3aregulatoryb pages 93-96).
  3. Mutant oligomerization as a manipulable mechanism (2024): Structural work showed that AML-associated R882H/R882C substitutions enhance abnormal intermolecular contacts and polymerization. Structure-guided DNMT3B-converting substitutions reduced mutant polymerization, improved substrate access, and suppressed dominant-negative behavior in cells (published April 2024; https://doi.org/10.1038/s41467-024-47398-y). This is human disease research, not equine application, but it demonstrates that oligomerization is mechanistically actionable.
  4. Allosteric inhibitor development (2024): Structural investigation of phthalazinone derivatives explored inhibition outside the universally conserved SAM/catalytic site, aiming for improved DNMT3A selectivity (https://doi.org/10.1021/acsmedchemlett.3c00528) (schmelmer2026targetingdnmt3aregulatorya pages 91-93, schmelmer2026targetingdnmt3aregulatoryb pages 91-93).
  5. Equine fibrogenesis (2023): The mare fibroblast study connected TGF-β1 signaling with selective DNMT3A-transcript induction and showed that 5-aza-dC reduced both DNMT3A transcript and collagen output, providing a preliminary veterinary translational application (alpoimmoreira20235aza2′deoxycytidine(5azadcdecitabine) pages 7-10).

7. Current and prospective applications

Equine reproductive biotechnology

DNA-methylation measurements are already used to assess equine gametes, ICSI embryos, cloned embryos, and placenta. Potential DNMT3A-focused applications include evaluating oocyte competence, embryo-culture effects, nuclear-transfer reprogramming, imprint integrity, and placental development. Current assays generally measure methylation marks or transcriptomes, however, rather than A0A9L0TK01 activity. Consequently, DNMT3A should not yet be used as a validated standalone equine fertility biomarker.

Endometrosis and fibrosis

The 2023 fibroblast results nominate the TGF-β1–DNMT3A axis as a candidate component of mare endometrial fibrosis. Decitabine reduced collagen output in vitro, but systemic or intrauterine use would require substantial safety work because nucleoside DNMT inhibitors are nonselective, require DNA incorporation, and can cause genome-wide hypomethylation and cytotoxicity. Selective allosteric or locus-targeted approaches remain experimental (alpoimmoreira20235aza2′deoxycytidine(5azadcdecitabine) pages 3-5, alpoimmoreira20235aza2′deoxycytidine(5azadcdecitabine) pages 7-10).

Epigenome engineering and mechanistic research

Catalytic DNMT3A domains are commonly fused to programmable DNA-binding platforms such as dCas9 to install locus-specific methylation. For horse research, such systems could test whether methylation of a candidate promoter or enhancer is causal, but an equine-validated catalytic construct and stringent off-target methylome analysis would be necessary. This is a research application, not a current veterinary therapy.

8. Expert interpretation and confidence assessment

The most defensible annotation is:

A0A9L0TK01 is a predicted equine DNMT3A-family, SAM-dependent nuclear DNA cytosine-5 methyltransferase that probably establishes de novo DNA methylation on chromatin, principally at CpG sites, with targeting controlled by histone recognition and protein assembly.

Confidence is high for broad enzyme-family chemistry because the supplied EC number and ADD/C5-methyltransferase architecture agree with conserved mammalian DNMT3A mechanisms. Confidence is moderate that this exact accession represents a canonical full-length horse DNMT3A isoform, because the gene symbol is absent and PWWP was not listed. Confidence is low for isoform-specific localization, target loci, substrate kinetics, tissue distribution, and phenotypic functions in horse because those properties have not been experimentally established for A0A9L0TK01.

Equine TGF-β1-responsive DNMT3A transcription is genuine gene-specific evidence, but it should not be interpreted as proof that DNMT3A catalysis directly drives collagen expression. Similarly, equine embryo and placental methylation studies establish biologically important methylome dynamics but cannot attribute those changes to DNMT3A rather than DNMT1, DNMT3B, altered demethylation, cell-composition changes, or combined mechanisms (heras2017dynamicsof5methylcytosine pages 7-10, alpoimmoreira20235aza2′deoxycytidine(5azadcdecitabine) pages 7-10).

9. Priority experiments for definitive annotation

  1. Align A0A9L0TK01 with curated human, mouse, and horse-reference DNMT3A; confirm catalytic motifs, catalytic cysteine, ADD and PWWP domains, nuclear-localization determinants, completeness, and relationship to DNMT3A1/DNMT3A2.
  2. Link the protein unambiguously to the equine genomic locus and transcript XM_023619394.1 using exon structure and peptide mapping.
  3. Express purified A0A9L0TK01 and measure SAM-dependent methylation of unmethylated versus hemimethylated CpG DNA, non-CpG DNA, and modified nucleosomes.
  4. Establish localization with isoform-specific antibodies or tagged endogenous protein, followed by nuclear fractionation and microscopy.
  5. Map genomic occupancy and methylation consequences by CUT&RUN/ChIP-seq plus whole-genome bisulfite or enzymatic methyl-seq after DNMT3A-specific CRISPR depletion.
  6. In equine endometrial fibroblasts, replace nonspecific 5-aza-dC inference with DNMT3A-selective knockdown or editing and test methylation at collagen-pathway regulatory elements.

Overall, the literature supports a strong domain- and orthology-based functional annotation, augmented by limited direct equine transcript evidence, but not yet an experimentally complete characterization of accession A0A9L0TK01.

References

  1. (gilbert2026targetingdnamethylation pages 3-6): Julie Gilbert and Francesco Calzaferri. Targeting dna methylation: new paradigms and the advent of gene-selective tools. Jul 2026. URL: https://doi.org/10.1021/acs.chemrestox.6c00218, doi:10.1021/acs.chemrestox.6c00218. This article has 0 citations.

  2. (gilbert2026targetingdnamethylation pages 1-3): Julie Gilbert and Francesco Calzaferri. Targeting dna methylation: new paradigms and the advent of gene-selective tools. Jul 2026. URL: https://doi.org/10.1021/acs.chemrestox.6c00218, doi:10.1021/acs.chemrestox.6c00218. This article has 0 citations.

  3. (dupas2026dnmt3aincancer pages 2-3): Thomas Dupas, Enola Gautreau, Josianne Clavel, Noël J.-M. Raynal, and Serge McGraw. Dnmt3a in cancer: from epigenetic writer to oncogenic driver. Clinical Epigenetics, Apr 2026. URL: https://doi.org/10.1186/s13148-026-02127-8, doi:10.1186/s13148-026-02127-8. This article has 2 citations and is from a peer-reviewed journal.

  4. (davletgildeeva2024theroleof pages 7-8): Anastasiia T. Davletgildeeva and Nikita A. Kuznetsov. The role of dnmt methyltransferases and tet dioxygenases in the maintenance of the dna methylation level. Biomolecules, 14:1117, Sep 2024. URL: https://doi.org/10.3390/biom14091117, doi:10.3390/biom14091117. This article has 82 citations.

  5. (alpoimmoreira20235aza2′deoxycytidine(5azadcdecitabine) pages 5-7): Joana Alpoim-Moreira, Anna Szóstek-Mioduchowska, Magda Słyszewska, Maria Rosa Rebordão, Dariusz J. Skarzynski, and Graça Ferreira-Dias. 5-aza-2′-deoxycytidine (5-aza-dc, decitabine) inhibits collagen type i and iii expression in tgf-β1-treated equine endometrial fibroblasts. Animals : an Open Access Journal from MDPI, 13:1212, Mar 2023. URL: https://doi.org/10.3390/ani13071212, doi:10.3390/ani13071212. This article has 10 citations.

  6. (alpoimmoreira20235aza2′deoxycytidine(5azadcdecitabine) pages 7-10): Joana Alpoim-Moreira, Anna Szóstek-Mioduchowska, Magda Słyszewska, Maria Rosa Rebordão, Dariusz J. Skarzynski, and Graça Ferreira-Dias. 5-aza-2′-deoxycytidine (5-aza-dc, decitabine) inhibits collagen type i and iii expression in tgf-β1-treated equine endometrial fibroblasts. Animals : an Open Access Journal from MDPI, 13:1212, Mar 2023. URL: https://doi.org/10.3390/ani13071212, doi:10.3390/ani13071212. This article has 10 citations.

  7. (gibson2017negativeuterineasynchrony pages 6-10): Charlotte Gibson, Marta de Ruijter-Villani, and Tom A.E. Stout. Negative uterine asynchrony retards early equine conceptus development and upregulation of placental imprinted genes. Placenta, 57:175-182, Sep 2017. URL: https://doi.org/10.1016/j.placenta.2017.07.007, doi:10.1016/j.placenta.2017.07.007. This article has 27 citations and is from a domain leading peer-reviewed journal.

  8. (heras2017dynamicsof5methylcytosine pages 7-10): Sonia Heras, Katrien Smits, Catharina De Schauwer, and Ann Van Soom. Dynamics of 5-methylcytosine and 5-hydroxymethylcytosine during pronuclear development in equine zygotes produced by icsi. Epigenetics & Chromatin, Mar 2017. URL: https://doi.org/10.1186/s13072-017-0120-x, doi:10.1186/s13072-017-0120-x. This article has 24 citations and is from a peer-reviewed journal.

  9. (heras2017dynamicsof5methylcytosine pages 1-2): Sonia Heras, Katrien Smits, Catharina De Schauwer, and Ann Van Soom. Dynamics of 5-methylcytosine and 5-hydroxymethylcytosine during pronuclear development in equine zygotes produced by icsi. Epigenetics & Chromatin, Mar 2017. URL: https://doi.org/10.1186/s13072-017-0120-x, doi:10.1186/s13072-017-0120-x. This article has 24 citations and is from a peer-reviewed journal.

  10. (wnuk2014changesindna pages 6-7): Maciej Wnuk, Anna Lewinska, Artur Gurgul, Tomasz Zabek, Leszek Potocki, Bernadetta Oklejewicz, Monika Bugno-Poniewierska, Magdalena Wegrzyn, and Ewa Slota. Changes in dna methylation patterns and repetitive sequences in blood lymphocytes of aged horses. AGE, 36:31-48, May 2014. URL: https://doi.org/10.1007/s11357-013-9541-z, doi:10.1007/s11357-013-9541-z. This article has 24 citations.

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  13. (wapenaar2024thenterminalregion pages 3-4): Hannah Wapenaar, Gillian Clifford, Willow Rolls, Moira Pasquier, Hayden Burdett, Yujie Zhang, Gauri Deák, Juan Zou, Christos Spanos, Mark R D Taylor, Jacquie Mills, James A Watson, Dhananjay Kumar, Richard Clark, Alakta Das, Devisree Valsakumar, Janice Bramham, Philipp Voigt, Duncan Sproul, and Marcus D Wilson. The n-terminal region of dnmt3a engages the nucleosome surface to aid chromatin recruitment. EMBO Reports, 25:5743-5779, Nov 2024. URL: https://doi.org/10.1038/s44319-024-00306-3, doi:10.1038/s44319-024-00306-3. This article has 21 citations and is from a highest quality peer-reviewed journal.

  14. (schmelmer2026targetingdnmt3aregulatory pages 9-15): BMF Schmelmer. Targeting dnmt3a regulatory interactions for selective epigenetic inhibition. Unknown journal, 2026.

  15. (davletgildeeva2024theroleof pages 5-7): Anastasiia T. Davletgildeeva and Nikita A. Kuznetsov. The role of dnmt methyltransferases and tet dioxygenases in the maintenance of the dna methylation level. Biomolecules, 14:1117, Sep 2024. URL: https://doi.org/10.3390/biom14091117, doi:10.3390/biom14091117. This article has 82 citations.

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  17. (garcia2023baseeditorscanning pages 12-15): Emma M. Garcia, Nicholas Z. Lue, Jessica K. Liang, Whitney K. Lieberman, Derek D. Hwang, James Woods, and Brian B. Liau. Base editor scanning reveals activating mutations of dnmt3a. bioRxiv, Apr 2023. URL: https://doi.org/10.1101/2023.04.12.536656, doi:10.1101/2023.04.12.536656. This article has 12 citations.

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  19. (odoherty2012bovinednamethylation pages 8-8): Alan M. O'Doherty, Lynne C. O'Shea, and Trudee Fair. Bovine dna methylation imprints are established in an oocyte size-specific manner, which are coordinated with the expression of the dnmt3 family proteins1. Biology of Reproduction, 86(3):67, Mar 2012. URL: https://doi.org/10.1095/biolreprod.111.094946, doi:10.1095/biolreprod.111.094946. This article has 136 citations and is from a peer-reviewed journal.

  20. (odoherty2012bovinednamethylation pages 8-9): Alan M. O'Doherty, Lynne C. O'Shea, and Trudee Fair. Bovine dna methylation imprints are established in an oocyte size-specific manner, which are coordinated with the expression of the dnmt3 family proteins1. Biology of Reproduction, 86(3):67, Mar 2012. URL: https://doi.org/10.1095/biolreprod.111.094946, doi:10.1095/biolreprod.111.094946. This article has 136 citations and is from a peer-reviewed journal.

  21. (odoherty2012bovinednamethylation pages 1-2): Alan M. O'Doherty, Lynne C. O'Shea, and Trudee Fair. Bovine dna methylation imprints are established in an oocyte size-specific manner, which are coordinated with the expression of the dnmt3 family proteins1. Biology of Reproduction, 86(3):67, Mar 2012. URL: https://doi.org/10.1095/biolreprod.111.094946, doi:10.1095/biolreprod.111.094946. This article has 136 citations and is from a peer-reviewed journal.

  22. (kim2025theroleof pages 6-7): Dae Joong Kim. The role of the dna methyltransferase family and the therapeutic potential of dnmt inhibitors in tumor treatment. Feb 2025. URL: https://doi.org/10.3390/curroncol32020088, doi:10.3390/curroncol32020088. This article has 70 citations.

  23. (alpoimmoreira20235aza2′deoxycytidine(5azadcdecitabine) pages 3-5): Joana Alpoim-Moreira, Anna Szóstek-Mioduchowska, Magda Słyszewska, Maria Rosa Rebordão, Dariusz J. Skarzynski, and Graça Ferreira-Dias. 5-aza-2′-deoxycytidine (5-aza-dc, decitabine) inhibits collagen type i and iii expression in tgf-β1-treated equine endometrial fibroblasts. Animals : an Open Access Journal from MDPI, 13:1212, Mar 2023. URL: https://doi.org/10.3390/ani13071212, doi:10.3390/ani13071212. This article has 10 citations.

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Artifacts

Citations

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  2. wnuk2014changesindna pages 6-7
  3. wapenaar2024thenterminalregion pages 3-4
  4. gilbert2026targetingdnamethylation pages 3-6
  5. gilbert2026targetingdnamethylation pages 1-3
  6. davletgildeeva2024theroleof pages 7-8
  7. wapenaar2024thenterminalregion pages 10-11
  8. wapenaar2024thenterminalregion pages 13-14
  9. davletgildeeva2024theroleof pages 5-7
  10. garcia2023baseeditorscanning pages 12-15
  11. odoherty2012bovinednamethylation pages 8-8
  12. odoherty2012bovinednamethylation pages 8-9
  13. odoherty2012bovinednamethylation pages 1-2
  14. kim2025theroleof pages 6-7
  15. https://doi.org/10.1038/s44319-024-00306-3
  16. https://doi.org/10.1186/s13072-017-0120-x
  17. https://doi.org/10.3390/ani13071212
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