Affinage

ZNF224

Zinc finger protein 224 · UniProt Q9NZL3

Length
707 aa
Mass
82.3 kDa
Annotated
2026-04-28
20 papers in source corpus 17 papers cited in narrative 17 extracted findings

Mechanistic narrative

Synthesis pass · prose summary of the discoveries below

ZNF224 is a KRAB-domain zinc finger transcription factor that functions as both a transcriptional repressor and a context-dependent transcriptional co-activator, integrating chromatin-modifying activities with oncogenic and stress signaling pathways. As a repressor, ZNF224 binds specific promoter elements (aldolase A, CIC, c-Myc, AXL) and recruits the KAP-1 co-repressor and the arginine methyltransferase PRMT5, which catalyzes symmetric dimethylation of histone H4R3, with repression also requiring HDAC activity (PMID:16150558, PMID:19741270, PMID:19505435, PMID:29423056). As a co-factor for WT1, ZNF224 enhances WT1-mediated activation of proapoptotic genes and counteracts WT1 repression at other promoters such as IRF8, with its own expression regulated downstream of BCR-ABL/WT1 signaling and restored by tyrosine kinase inhibitors (PMID:20591825, PMID:23362234, PMID:26563595, PMID:26320177). ZNF224 also activates miR-663a transcription to suppress p53/p21, promotes TGF-β-driven EMT in melanoma, sustains NF-κB survival signaling and cyclin D3 expression in CLL, and is stabilized during DNA damage by MED28 interaction via the KRAB domain (PMID:27105517, PMID:34181020, PMID:36425656, PMID:28040726, PMID:29435049).

Mechanistic history

Synthesis pass · year-by-year structured walk · 14 steps
  1. 2005 High

    The molecular mechanism by which ZNF224 represses transcription was established: ZNF224 binds the aldolase A promoter in vivo and requires its KRAB-A domain for KAP-1 co-repressor recruitment and HDAC-dependent silencing, defining it as a KRAB-ZFP transcriptional repressor.

    Evidence ChIP, KRAB domain mutagenesis, reporter assays, and TSA treatment in human cells

    PMID:16150558

    Open questions at the time
    • No genome-wide target repertoire defined
    • Specific HDAC isoform(s) involved not identified
  2. 2007 High

    Comparative analysis with isoform ZNF255 showed ZNF224 is homogeneously nuclear and a more potent repressor, distinguishing the functional specialization of these paralogous isoforms.

    Evidence Immunofluorescence, ChIP, and reporter assays comparing ZNF224 and ZNF255

    PMID:17900823

    Open questions at the time
    • Determinants of differential subnuclear distribution not mapped
  3. 2009 High

    A chromatin-level repressive mechanism was resolved: ZNF224 recruits the arginine methyltransferase PRMT5 to target promoters, where PRMT5 symmetrically dimethylates H4R3, and PRMT5 knockdown relieves repression — establishing a histone-modification arm of ZNF224-mediated silencing beyond HDACs.

    Evidence Reciprocal Co-IP, ChIP for histone marks, RNAi of PRMT5, histone methylation assays

    PMID:19741270

    Open questions at the time
    • Whether PRMT5 and HDAC act sequentially or in parallel not determined
    • Generality of PRMT5 recruitment to other ZNF224 targets unknown
  4. 2009 High

    A second direct transcriptional target was identified: ZNF224 was biochemically purified as the factor binding the CIC gene silencer, extending its repressor role to metabolite transport genes.

    Evidence DNA affinity purification from nuclear extracts, overexpression/silencing reporter assays, RT-PCR

    PMID:19505435

    Open questions at the time
    • Whether CIC repression also involves PRMT5/KAP-1 not tested
  5. 2010 High

    Two new functional partnerships were discovered: DEPDC1 interacts with ZNF224 to co-repress the NF-κB inhibitor A20 (disruption induces apoptosis), and WT1(-KTS) interacts with ZNF224 to enhance transcriptional activation — revealing ZNF224 can switch from repressor to co-activator depending on its protein partner.

    Evidence Co-IP, cell-permeable peptide disruption, reporter assays, apoptosis assays (DEPDC1); Co-IP, subcellular fractionation, reporter assays (WT1)

    PMID:20587513 PMID:20591825

    Open questions at the time
    • Structural basis of DEPDC1–ZNF224 versus WT1–ZNF224 complex specificity unknown
    • Genomic targets co-regulated by DEPDC1–ZNF224 not mapped
  6. 2013 Medium

    The context-dependent co-factor role of ZNF224 with WT1 was elaborated: on proapoptotic promoters ZNF224 enhances WT1 activation, while on antiapoptotic promoters it suppresses WT1 activity, and cytarabine induces ZNF224 to potentiate apoptosis in CML cells.

    Evidence Co-transfection reporter assays, gene expression profiling, drug treatment in K562 CML cells

    PMID:23362234

    Open questions at the time
    • Promoter features that determine co-activation versus co-repression not defined
    • Single lab/cell line system
  7. 2015 High

    ZNF224 was placed within the BCR-ABL signaling axis: BCR-ABL via WT1 represses ZNF224, and TKI treatment restores its expression; independently, ZNF224 counteracts WT1 repression at the IRF8 promoter, linking ZNF224 to innate immune gene regulation in leukemia.

    Evidence Epistasis experiments with BCR-ABL/WT1, TKI treatment, primary CML samples; ChIP at IRF8 promoter, shRNA knockdown

    PMID:26320177 PMID:26563595

    Open questions at the time
    • Whether ZNF224 restoration is required for full TKI cytotoxicity not shown in vivo
  8. 2016 High

    A genome-wide DNA binding motif (5′-CAGC-3′) was identified for ZNF224 by ChIP-seq, and a direct transcriptional activation target, miR-663a, was characterized; miR-663a in turn suppresses p53 and p21, revealing a ZNF224–miRNA–p53 signaling cascade.

    Evidence ChIP-seq, SPR, ELISA, luciferase reporter, miRNA inhibitor rescue

    PMID:27105517

    Open questions at the time
    • Full ChIP-seq target catalog not published
    • How ZNF224 switches from repression to activation at this locus not explained
  9. 2017 High

    ZNF224 was shown to directly repress c-Myc transcription in CML cells upon TKI/JAK2 inhibitor treatment, extending its repressor targets to a master oncogene; separately, MED28 was identified as a physical partner that stabilizes ZNF224 protein during DNA damage via KRAB domain interaction.

    Evidence ChIP and reporter assays for c-Myc; Co-IP, SPR, BiFC for MED28 interaction; colony formation after camptothecin

    PMID:29423056 PMID:29435049

    Open questions at the time
    • Ubiquitin-proteasome pathway regulating ZNF224 turnover not identified
    • Whether MED28 stabilization affects all ZNF224 targets not tested
  10. 2017 Medium

    In CLL, ZNF224 was found to positively regulate cyclin D3 expression and influence cell cycle progression and apoptosis resistance, broadening its oncogenic role beyond CML.

    Evidence Knockdown and overexpression with cell cycle and apoptosis readouts in CLL cells

    PMID:28040726

    Open questions at the time
    • Direct versus indirect regulation of CCND3 promoter not resolved
    • Patient cohort functional validation lacking
  11. 2018 Medium

    ZNF224 was shown to transcriptionally repress AXL in CML, and its overexpression partially restores imatinib sensitivity in resistant cells, connecting ZNF224 loss to drug resistance mechanisms.

    Evidence Overexpression, reporter assay, viability assay in imatinib-resistant CML cells

    PMID:30176265

    Open questions at the time
    • In vivo drug resistance model not tested
    • ChIP confirmation of direct AXL promoter binding not provided
  12. 2021 Medium

    Beyond hematopoietic malignancies, ZNF224 was shown to be TGF-β-inducible in melanoma and to potentiate EMT through a positive feedback loop upregulating TGF-β pathway components, establishing a role in epithelial plasticity.

    Evidence siRNA/overexpression, invasion assays, gene expression analysis, TGF-β stimulation in melanoma cells

    PMID:34181020

    Open questions at the time
    • Direct DNA-binding targets mediating EMT not identified
    • In vivo metastasis data absent
  13. 2022 Medium

    ZNF224 was functionally linked to NF-κB pathway activation in CLL: its knockdown reduces NF-κB activity and increases apoptosis in primary patient cells, establishing a pro-survival role through NF-κB.

    Evidence RNAi, NF-κB activity assays, apoptosis assays in primary CLL cells

    PMID:36425656

    Open questions at the time
    • Whether NF-κB regulation is direct or via A20/DEPDC1 axis not clarified in CLL context
  14. 2025 Medium

    In melanoma, ZNF224 was found to promote p21 transcription in a p53-dependent manner yet simultaneously enhance AKT-mediated cytosolic retention of p21 protein, converting p21 from a tumor suppressor to a proliferation-promoting factor — reconciling the paradox of ZNF224 activating p21 while promoting survival.

    Evidence Overexpression, reporter assays, AKT inhibition, subcellular fractionation, transcriptomic analysis in melanoma cells

    PMID:40321146

    Open questions at the time
    • AKT activation mechanism by ZNF224 not identified
    • Single cell line system

Open questions

Synthesis pass · forward-looking unresolved questions
  • Key unresolved questions include the structural basis for ZNF224's context-dependent switch between repression and activation, the complete genome-wide target repertoire, the E3 ligase(s) controlling its proteasomal turnover, and whether its dual roles in leukemia and solid tumors reflect shared or distinct molecular mechanisms.
  • No crystal or cryo-EM structure available
  • Genome-wide direct target catalog from ChIP-seq not published in full
  • Ubiquitin ligase for ZNF224 degradation not identified

Mechanism profile

Synthesis pass · controlled-vocabulary classification · explore literature graph →
Molecular activity
GO:0140110 transcription regulator activity 7 GO:0003677 DNA binding 4
Localization
GO:0005634 nucleus 3
Pathway
R-HSA-74160 Gene expression (Transcription) 5 R-HSA-162582 Signal Transduction 3 R-HSA-5357801 Programmed Cell Death 2 R-HSA-1640170 Cell Cycle 1 R-HSA-4839726 Chromatin organization 1
Partners
DEPDC1KAP1MED28PRMT5WT1

Evidence

Reading pass · 17 per-paper findings extracted from the source corpus
Year Finding Method Journal Conf PMIDs
2005 ZNF224 binds in vivo to the distal promoter of the aldolase A gene and represses its transcription; this repression requires the 45-amino acid KRAB A domain and specific interaction with the KAP-1 co-repressor, and also requires histone deacetylases (demonstrated by HDAC1 inhibitor trichostatin A treatment). Chromatin immunoprecipitation (ChIP), transient transfection/co-transfection reporter assays, HDAC inhibitor treatment, co-repressor interaction studies Gene High 16150558
2007 ZNF224 is homogeneously distributed in the nucleus and binds the aldolase A negative regulatory element (AldA-NRE) to repress transcription more efficiently than its isoform ZNF255, which localizes to subnuclear structures associated with nucleoli and also to the cytoplasm. Transient transfection of recombinant proteins, ChIP, northern blot, PCR, immunofluorescence localization Gene High 17900823
2009 ZNF224 physically associates with the arginine methyltransferase PRMT5; PRMT5 is recruited to the L-type aldolase A promoter via ZNF224 and catalyzes symmetric dimethylation of arginine 3 of histone H4, contributing to transcriptional repression. PRMT5 knockdown by RNAi relieves repression of the aldolase A promoter. Co-immunoprecipitation, ChIP, RNA interference, histone methylation assay The Journal of biological chemistry High 19741270
2009 ZNF224 was purified from nuclear extracts by DNA affinity chromatography and identified as the transcription factor that binds the 26 bp silencer (-595/-569) of the mitochondrial citrate carrier (CIC) gene; ZNF224 overexpression decreases CIC promoter activity and CIC transcript/protein levels, while ZNF224 silencing activates CIC transcription. DNA affinity purification, overexpression/silencing reporter assays, RT-PCR, western blot Biochemical and biophysical research communications High 19505435
2010 DEPDC1 interacts and colocalizes with ZNF224 (a known transcriptional repressor); disruption of the DEPDC1-ZNF224 complex with a cell-permeable peptide induces apoptosis and triggers transcriptional activation of A20, an inhibitor of NF-κB signaling. Co-immunoprecipitation, immunocytochemistry, cell-permeable peptide inhibition, reporter assay, in vitro and in vivo apoptosis assays Cancer research High 20587513
2010 ZNF224 interacts with WT1(-KTS) isoform in the nucleus to enhance WT1-mediated transcriptional activation; its isoform ZNF255 interacts with WT1(+KTS) in a different subcellular compartment and participates in RNA processing rather than transcriptional regulation. Co-immunoprecipitation, subcellular fractionation, co-transfection transcriptional reporter assays Human molecular genetics High 20591825
2013 ZNF224 acts as a co-activator of WT1 on proapoptotic target gene promoters and suppresses WT1-mediated transactivation of antiapoptotic genes in CML K562 cells; cytosine arabinoside (ara-C) induces ZNF224 expression, enhancing apoptotic response. Co-transfection reporter assays, gene expression analysis, loss-of-function/gain-of-function, drug treatment Human molecular genetics Medium 23362234
2015 BCR-ABL oncogene, via upregulation of WT1, represses transcription of the ZNF224 gene; treatment with imatinib or second-generation tyrosine kinase inhibitors restores ZNF224 expression, placing ZNF224 downstream of BCR-ABL/WT1 in a pathway that controls apoptosis. Genetic epistasis (BCR-ABL/WT1 manipulation), RT-PCR, western blot, primary CML samples and cell lines, TKI treatment Oncotarget Medium 26320177
2015 ZNF224 counteracts WT1-mediated repression of the IRF8 promoter; WT1 recruits ZNF224 to the IRF8 promoter (shown by ChIP), and ZNF224 knockdown suppresses cytarabine-induced IRF8 upregulation in leukemic cells. ChIP, co-immunoprecipitation, luciferase reporter assay, shRNA knockdown, RT-PCR Leukemia research High 26563595
2016 ZNF224 binds to the miR-663a promoter via a consensus 5'-CAGC-3' DNA sequence (identified by ChIP-seq and confirmed by ELISA, SPR, and luciferase assay), activating miR-663a transcription; miR-663a then binds the 3' UTR of p53 and p21 to suppress their expression, promoting cell survival. ChIP-sequencing, ELISA, surface plasmon resonance (SPR), luciferase reporter assay, miRNA inhibitor rescue, qPCR Oncotarget High 27105517
2017 ZNF224 is a transcriptional repressor of c-Myc in CML; induction of ZNF224 by imatinib or the JAK2 inhibitor AG490 leads to c-Myc transcriptional repression and apoptosis, identifying a ZNF224/c-Myc axis in imatinib responsiveness. ChIP, reporter assays, qRT-PCR, overexpression/knockdown, pharmacological treatment Oncotarget Medium 29423056
2017 MED28 physically interacts with ZNF224 via the KRAB domain of ZNF224 and the MED domain of MED28 in the nucleus; MED28 overexpression stabilizes ZNF224 protein during DNA damage (camptothecin treatment), preventing its degradation and increasing colony formation. Co-immunoprecipitation, surface plasmon resonance, bimolecular fluorescence complementation (BiFC), western blot, colony formation assay Oncology letters High 29435049
2017 ZNF224 positively modulates cyclin D3 gene expression in CLL cells; alteration of ZNF224 expression leads to defects in cell cycle control, and ZNF224 promotes apoptosis resistance in CLL. Loss-of-function/gain-of-function, gene expression analysis, cell cycle analysis, apoptosis assays Human molecular genetics Medium 28040726
2018 ZNF224 transcriptionally represses the receptor tyrosine kinase AXL in CML cells; ZNF224 overexpression in imatinib-resistant CML cells suppresses AXL expression and partially restores imatinib sensitivity. Overexpression, qRT-PCR, western blot, luciferase reporter assay, cell viability assay Biochimie Medium 30176265
2021 ZNF224 expression is induced by TGF-β in melanoma cells; ZNF224 potentiates TGF-β-induced activation of EMT target genes and positively modulates TGF-β, TβR1, and TβR2 expression, creating a positive regulatory loop that enhances EMT and invasiveness. Overexpression, knockdown (siRNA), gene expression analysis, invasion/proliferation assays, TGF-β stimulation experiments Human molecular genetics Medium 34181020
2022 ZNF224 knockdown reduces NF-κB pathway activity in CLL cells, raises spontaneous and drug-induced apoptosis, and inhibits proliferation of primary CLL cells, placing ZNF224 as a positive regulator of NF-κB survival signaling in CLL. RNA interference, NF-κB activity assays, apoptosis assays, primary patient cells Frontiers in molecular biosciences Medium 36425656
2025 ZNF224 overexpression in melanoma cells promotes p21(CIP1/WAF1) gene transcription in a p53-dependent manner, and also enhances AKT-triggered cytosolic retention of p21 protein, thereby inhibiting apoptosis and favoring cell proliferation. Overexpression, gene expression analysis, reporter assays, AKT pathway inhibition, subcellular fractionation, transcriptomic data analysis The FEBS journal Medium 40321146

Source papers

Stage 0 corpus · 20 papers · ranked by NIH iCite citations
Year Title Journal Citations PMID
2010 Cell-permeable peptide DEPDC1-ZNF224 interferes with transcriptional repression and oncogenicity in bladder cancer cells. Cancer research 86 20587513
2005 The Krüppel-like zinc-finger protein ZNF224 represses aldolase A gene transcription by interacting with the KAP-1 co-repressor protein. Gene 33 16150558
2016 ZNF224, Krüppel like zinc finger protein, induces cell growth and apoptosis-resistance by down-regulation of p21 and p53 via miR-663a. Oncotarget 31 27105517
2009 The Kruppel-like zinc finger protein ZNF224 recruits the arginine methyltransferase PRMT5 on the transcriptional repressor complex of the aldolase A gene. The Journal of biological chemistry 31 19741270
2010 Biochemical and functional interaction between ZNF224 and ZNF255, two members of the Kruppel-like zinc-finger protein family and WT1 protein isoforms. Human molecular genetics 26 20591825
2009 Transcription of the mitochondrial citrate carrier gene: identification of a silencer and its binding protein ZNF224. Biochemical and biophysical research communications 24 19505435
2013 Role of WT1-ZNF224 interaction in the expression of apoptosis-regulating genes. Human molecular genetics 22 23362234
2015 WT1-mediated repression of the proapoptotic transcription factor ZNF224 is triggered by the BCR-ABL oncogene. Oncotarget 19 26320177
2021 ZNF224 is a mediator of TGF-β pro-oncogenic function in melanoma. Human molecular genetics 16 34181020
2017 Role of ZNF224 in c-Myc repression and imatinib responsiveness in chronic myeloid leukemia. Oncotarget 15 29423056
2015 The hematopoietic tumor suppressor interferon regulatory factor 8 (IRF8) is upregulated by the antimetabolite cytarabine in leukemic cells involving the zinc finger protein ZNF224, acting as a cofactor of the Wilms' tumor gene 1 (WT1) protein. Leukemia research 15 26563595
2017 Role of ZNF224 in cell growth and chemoresistance of chronic lymphocitic leukemia. Human molecular genetics 14 28040726
2010 ZNF224: Structure and role of a multifunctional KRAB-ZFP protein. The international journal of biochemistry & cell biology 14 21187159
2007 Differential expression and cellular localization of ZNF224 and ZNF255, two isoforms of the Krüppel-like zinc-finger protein family. Gene 14 17900823
2018 ZNF224 is a transcriptional repressor of AXL in chronic myeloid leukemia cells. Biochimie 12 30176265
2016 The Complex Role of the ZNF224 Transcription Factor in Cancer. Advances in protein chemistry and structural biology 12 28215224
2017 MED28 increases the colony-forming ability of breast cancer cells by stabilizing the ZNF224 protein upon DNA damage. Oncology letters 9 29435049
2022 Biological relevance of ZNF224 expression in chronic lymphocytic leukemia and its implication IN NF-kB pathway regulation. Frontiers in molecular biosciences 7 36425656
2021 ZNF224 Protein: Multifaceted Functions Based on Its Molecular Partners. Molecules (Basel, Switzerland) 6 34684876
2025 ZNF224 enhances the oncogenic function of p21 via p53 and AKT pathways in melanoma. The FEBS journal 1 40321146