Affinage

SETD4

SET domain-containing protein 4 · UniProt Q9NVD3

Length
440 aa
Mass
50.4 kDa
Annotated
2026-04-28
16 papers in source corpus 12 papers cited in narrative 12 extracted findings

Mechanistic narrative

Synthesis pass · prose summary of the discoveries below

SETD4 is a lysine methyltransferase that functions as a central epigenetic regulator of cellular quiescence and inflammatory signaling through methylation of both histone and non-histone substrates. Its principal chromatin-level activity is trimethylation of H4K20 (H4K20me3), which drives heterochromatin formation and enforces quiescence in multiple stem/progenitor cell types including neural stem cells, cardiac progenitor cells, hepatic reserve cells, and cancer stem cells, acting upstream of the PI3K-Akt-mTOR pathway (PMID:28031330, PMID:34079011, PMID:36027907, PMID:41177404). SETD4 also catalyzes H3K4me1/me2 at inflammatory gene promoters to activate TNF-α and IL-6 transcription in macrophages (PMID:31376731), and H3K27me3 at the NUPR1 promoter to repress prostate cancer tumorigenesis (PMID:37879429). Beyond histones, SETD4 methylates KU70 at K570 to suppress apoptosis (PMID:35545041) and TBK1 at K607—recruited via the adaptor ZNF268a—to promote antiviral interferon signaling (PMID:37926288).

Mechanistic history

Synthesis pass · year-by-year structured walk · 8 steps
  1. 2013 Medium

    Initial characterization established SETD4 as a dual-compartment (cytosolic/nuclear) lysine methyltransferase whose loss impairs breast cancer cell proliferation and G1/S transition, linking this uncharacterized SET-domain protein to cell cycle control.

    Evidence siRNA knockdown in breast cancer cells with cell fractionation, flow cytometry, and cyclin D1 western blot

    PMID:24738023

    Open questions at the time
    • No specific histone or non-histone substrate identified
    • Single cancer cell line, unclear generalizability
    • Mechanism connecting SETD4 to cyclin D1 expression undefined
  2. 2017 High

    The first enzymatic substrate was identified: SETD4 catalyzes H4K20 trimethylation, and this activity is required for heterochromatin-dependent cellular quiescence, establishing SETD4 as an H4K20me3 writer.

    Evidence In vitro HMT assay on histones plus Artemia siRNA knockdown showing H4K20me3 loss and failure to enter diapause quiescence

    PMID:28031330

    Open questions at the time
    • Whether mammalian SETD4 performs the same H4K20me3 reaction in vivo not yet shown
    • Structural basis for H4K20 specificity unknown
  3. 2019 High

    SETD4 was shown to possess a second, distinct histone substrate specificity—H3K4me1/me2—and to translocate to the nucleus upon inflammatory stimulation, directly linking its methyltransferase activity to activation of TNF-α and IL-6 transcription in macrophages.

    Evidence SETD4-knockout mouse bone marrow-derived macrophages, in vitro HMT assay, ChIP at TNF-α/IL-6 promoters, immunofluorescence for nuclear translocation

    PMID:31376731

    Open questions at the time
    • Dual substrate specificity (H4K20me3 vs H3K4me1/me2) regulation or context dependence unclear
    • Mechanism of stimulus-dependent nuclear translocation unresolved
  4. 2021 Medium

    Mammalian in vivo studies confirmed that SETD4-mediated H4K20me3 enforces quiescence in both cardiac progenitor cells and neural stem cells, with conditional knockout causing quiescence exit and functional consequences (cardiac repair, neurogenesis), generalizing the quiescence mechanism across tissue-resident stem cells.

    Evidence Conditional knockout mice (c-Kit-CreERT2;Setd4f/f for cardiac; lineage tracing/OE for NSCs), H4K20me3 immunostaining, pathway analysis (PI3K-Akt-mTOR)

    PMID:34079011 PMID:36027907

    Open questions at the time
    • Direct H4K20me3 ChIP-seq genome-wide targets in mammalian quiescent cells not mapped
    • Whether PI3K-Akt-mTOR suppression is a direct H4K20me3 target gene effect or indirect remains unclear
  5. 2022 High

    SETD4 was revealed to methylate the non-histone substrate KU70 at K570, establishing a cytoplasmic function whereby methylated KU70 suppresses apoptosis—the first demonstration that SETD4's cytosolic fraction has a defined substrate and biological role.

    Evidence Co-IP, in vitro methylation assay, site-directed mutagenesis of SETD4 (Y272F/Y284F) and KU70 (K570R), apoptosis readout by flow cytometry

    PMID:35545041

    Open questions at the time
    • Whether KU70 methylation at K570 affects DNA repair function in addition to apoptosis not tested
    • Structural basis for SETD4 recognizing KU70 vs. histones unknown
  6. 2023 High

    A second non-histone substrate, TBK1 (K607), was identified, with the adaptor ZNF268a mediating recruitment of SETD4 to TBK1 upon viral infection, establishing a role for SETD4 in innate antiviral interferon signaling and revealing a paradigm for adaptor-dependent substrate selection.

    Evidence Reciprocal co-IP of ZNF268a–SETD4–TBK1, in vitro methylation assay, K607 mutagenesis, IFN signaling reporter and functional readout

    PMID:37926288

    Open questions at the time
    • Full spectrum of adaptor proteins directing SETD4 to other substrates unknown
    • In vivo antiviral phenotype of SETD4 KO not reported
  7. 2023 Medium

    A third histone specificity—H3K27me3 at the NUPR1 promoter—was attributed to SETD4, with repression of NUPR1 inactivating Akt signaling and suppressing prostate cancer tumorigenesis, expanding the catalog of SETD4 histone marks to include a repressive modification beyond H4K20me3.

    Evidence SETD4 knockdown in prostate cancer cells, ChIP for H3K27me3 at NUPR1 promoter, Akt pathway western blot

    PMID:37879429

    Open questions at the time
    • In vitro methyltransferase assay for H3K27 not reported; SETD4 could recruit another HMT
    • Single promoter examined; genome-wide H3K27me3 changes upon SETD4 loss unknown
  8. 2025 High

    CUT&RUN-seq in hepatic reserve cells demonstrated that H4K20me3 deposited by SETD4 directly silences metabolic gene loci and that chromatin remodeling upon injury releases this silencing to initiate liver regeneration, providing the first genome-wide chromatin map of SETD4-dependent quiescence.

    Evidence Setd4-CreERT2 lineage tracing, targeted ablation, CUT&RUN-seq for H4K20me3, RNA-seq, chromatin accessibility in chronic liver injury models

    PMID:41177404

    Open questions at the time
    • Chromatin remodelers that reverse H4K20me3-mediated silencing not identified
    • Whether SETD4 is the sole H4K20me3 writer in hepatic dormant cells or acts redundantly with SUV420H1/H2 unresolved

Open questions

Synthesis pass · forward-looking unresolved questions
  • How SETD4 achieves substrate selectivity across at least three histone marks (H4K20me3, H3K4me1/me2, H3K27me3) and two non-histone substrates in different cellular contexts remains a central unresolved question.
  • No structural model of SETD4 catalytic domain with any substrate
  • Context-dependent regulatory mechanisms (post-translational modifications, adaptor proteins beyond ZNF268a) largely uncharacterized
  • Whether multi-substrate specificity reflects direct catalysis in every case or indirect recruitment of other methyltransferases is not fully resolved for H3K27

Mechanism profile

Synthesis pass · controlled-vocabulary classification · explore literature graph →
Molecular activity
GO:0016740 transferase activity 4 GO:0042393 histone binding 3 GO:0140096 catalytic activity, acting on a protein 2
Localization
GO:0005634 nucleus 2 GO:0005829 cytosol 2
Pathway
R-HSA-4839726 Chromatin organization 5 R-HSA-162582 Signal Transduction 2 R-HSA-168256 Immune System 2 R-HSA-5357801 Programmed Cell Death 1
Partners
KU70PTBP1TBK1ZNF268A

Evidence

Reading pass · 12 per-paper findings extracted from the source corpus
Year Finding Method Journal Conf PMIDs
2013 SETD4 is a lysine methyltransferase that localizes to both the cytosol and nucleus in breast cancer cells, and its knockdown suppresses proliferation, delays G1/S cell cycle transition, and decreases cyclin D1 expression without affecting apoptosis. Cell fractionation, confocal immunofluorescence, siRNA knockdown, western blot, flow cytometry Journal of cancer science & therapy Medium 24738023
2017 SETD4 (Ar-SETD4) catalyzes trimethylation of histone H4K20 (H4K20me3) to promote cell quiescence; knockdown of Ar-SETD4 significantly reduces H4K20me3 levels and prevents quiescent diapause embryo formation in Artemia. In vitro histone methyltransferase (HMT) assay, overexpression in cell lines, siRNA knockdown, western blot Molecular and cellular biology High 28031330
2019 SETD4 translocates from the cytosol to the nucleus upon LPS stimulation and catalyzes H3K4 monomethylation and dimethylation (H3K4me1/me2) at the TNF-α and IL-6 promoters, thereby positively regulating inflammatory cytokine expression in macrophages downstream of MAPK and NF-κB pathways. In vitro HMTase assay, SETD4-/- mouse BMDMs, RNA interference, ChIP (H3K4me1/me2 at promoters), immunofluorescence for nuclear translocation Molecular immunology High 31376731
2021 Setd4 regulates quiescence of c-Kit+ cardiac progenitor cells via H4K20me3-mediated heterochromatin formation and through the PI3K-Akt-mTOR signaling pathway; conditional knockout of Setd4 causes quiescence exit, increased capillary endothelial cells, and improved cardiac function after myocardial infarction. Conditional knockout (c-Kit-CreERT2;Setd4f/f mice), lineage tracing (Setd4-Cre;Rosa26mT/mG), immunostaining for H4K20me3, pathway analysis Scientific reports Medium 34079011
2021 SETD4 knockout in bone marrow mesenchymal stem cells inhibits histone lysine monomethylases and dimethylases and alters genomic DNA methylation at 96,331 CpG sites (affecting promoter regions of genes involved in stem cell biology), impairs migration, myogenic differentiation, and angiogenesis via paracrine VEGF. CRISPR/Cas9 KO mice, Reduced Representation Bisulfite Sequencing (RRBS), western blot, functional assays (migration, differentiation, angiogenesis) Stem cell reviews and reports Medium 33506343
2022 SETD4 methylates the non-histone protein KU70 at lysine 570 (K570); mutations Y272F and Y284F in SETD4 abolish this methylation. Methylated KU70 is enriched in the cytoplasm and suppresses staurosporine-induced apoptosis; the KU70-K570R mutation dampens this anti-apoptotic activity. Co-IP, in vitro methylation assay, site-directed mutagenesis (SETD4-Y272/284F; KU70-K570R), overexpression/knockdown with apoptosis readout (flow cytometry, cell viability) Cell reports High 35545041
2022 SETD4 epigenetically regulates neural stem cell (NSC) quiescence via H4K20me3-mediated heterochromatin; conditional knockout of Setd4 causes quiescence exit and increased neurogenesis, while overexpression causes quiescence entry and suppressed neurogenesis, demonstrating SETD4 as an epigenetic determinant of deep NSC quiescence. Conditional knockout, lineage tracing, immunostaining for H4K20me3, overexpression in mice Stem cell reports Medium 36027907
2023 SETD4 methylates H3K27 to generate H3K27me3 at the NUPR1 promoter, repressing NUPR1 transcription, which subsequently inactivates the Akt signaling pathway and impedes prostate cancer tumorigenesis. SETD4 knockdown in PCa cells, ChIP for H3K27me3 at NUPR1 promoter, western blot for Akt pathway components Cancer letters Medium 37879429
2023 Upon viral infection, TBK1-stabilized ZNF268a recruits SETD4 to TBK1, which then catalyzes mono-methylation of TBK1 at lysine 607, critical for assembly of the TBK1 signaling complex and efficient antiviral interferon signaling. Co-IP (ZNF268a–SETD4–TBK1 interactions), in vitro methylation assay, site-directed mutagenesis, overexpression/knockdown with IFN signaling readout The Journal of biological chemistry High 37926288
2023 SETD4 promotes H4K20me3-mediated heterochromatin formation in quiescent lung cancer stem cells, leading to cell quiescence and PTEN-mediated inhibition of the PI3K-mTOR pathway, thereby conferring chemoresistance. SETD4 overexpression in lung cancer cells, H4K20me3 immunostaining, RNA-seq of activated vs. quiescent cells, PI3K-mTOR pathway western blot Stem cells international Medium 37274024
2022 The lncRNA CBR3-AS1 interacts with the RNA-binding protein PTBP1 to stabilize SETD4 mRNA, increasing SETD4 protein levels and promoting gestational choriocarcinoma cell proliferation; SETD4 is the functional downstream effector of the CBR3-AS1/PTBP1 axis. RNA binding protein immunoprecipitation (RIP), RNA pulldown, mRNA stability assay, siRNA knockdown, rescue assays Disease markers Medium 35655916
2025 Dormant Setd4+ hepatic cells maintain a silenced metabolic state through H4K20me3-mediated heterochromatin; chromatin remodeling increases accessibility, triggering activation from dormancy to initiate liver regeneration following chronic injury. Single-molecule FISH, lineage tracing (Setd4CreERT2;Rosa26lsl-tdTomato), targeted cell ablation (Setd4CreERT2;Rosa26DTA), CUT&RUN-seq for H4K20me3, bulk RNA-seq, chromatin accessibility analysis Journal of hepatology High 41177404

Source papers

Stage 0 corpus · 16 papers · ranked by NIH iCite citations
Year Title Journal Citations PMID
2013 SET domain-containing Protein 4 (SETD4) is a Newly Identified Cytosolic and Nuclear Lysine Methyltransferase involved in Breast Cancer Cell Proliferation. Journal of cancer science & therapy 33 24738023
2017 SETD4 Regulates Cell Quiescence and Catalyzes the Trimethylation of H4K20 during Diapause Formation in Artemia. Molecular and cellular biology 32 28031330
2019 The novel methyltransferase SETD4 regulates TLR agonist-induced expression of cytokines through methylation of lysine 4 at histone 3 in macrophages. Molecular immunology 25 31376731
2023 SETD4 inhibits prostate cancer development by promoting H3K27me3-mediated NUPR1 transcriptional repression and cell cycle arrest. Cancer letters 13 37879429
2021 Setd4 controlled quiescent c-Kit+ cells contribute to cardiac neovascularization of capillaries beyond activation. Scientific reports 13 34079011
2021 SETD4 in the Proliferation, Migration, Angiogenesis, Myogenic Differentiation and Genomic Methylation of Bone Marrow Mesenchymal Stem Cells. Stem cell reviews and reports 12 33506343
2022 SETD4-mediated KU70 methylation suppresses apoptosis. Cell reports 10 35545041
2021 SETD4-expressing cells contribute to pancreatic development and response to cerulein induced pancreatitis injury. Scientific reports 7 34131249
2023 SETD4 Confers Cancer Stem Cell Chemoresistance in Nonsmall Cell Lung Cancer Patients via the Epigenetic Regulation of Cellular Quiescence. Stem cells international 6 37274024
2022 CBR3-AS1 Accelerates the Malignant Proliferation of Gestational Choriocarcinoma Cells by Stabilizing SETD4. Disease markers 6 35655916
2022 SETD4 cells contribute to brain development and maintain adult stem cell reservoir for neurogenesis. Stem cell reports 6 36027907
2019 Loss of Setd4 delays radiation-induced thymic lymphoma in mice. DNA repair 6 31794893
2023 TBK1-stabilized ZNF268a recruits SETD4 to methylate TBK1 for efficient interferon signaling. The Journal of biological chemistry 4 37926288
2025 Identification of SETD4 as an Onco-Immunological Biomarker Encompassing the Tumor Microenvironment, Prognoses, and Therapeutic Responses in Various Human Cancers. Immunity, inflammation and disease 1 39817582
2026 SETD4 as a marker of disease burden and treatment response in childhood acute lymphoblastic leukemiaSETD4 as a marker of disease burden and treatment response in childhood acute lymphoblastic leukemia. Oncology letters 0 41947902
2025 Setd4-expressing cells drive regenerative recovery in chronic liver injury. Journal of hepatology 0 41177404