id: Q02556
gene_symbol: IRF8
product_type: PROTEIN
status: COMPLETE
taxon:
  id: NCBITaxon:9606
  label: Homo sapiens
description: >-
  IRF8 (Interferon Regulatory Factor 8, also known as ICSBP) is a transcription factor
  of the IRF family
  that binds to interferon-stimulated response elements (ISRE), EICE (ETS-IRF composite
  elements with PU.1),
  and AICE (AP-1-IRF composite elements with BATF/JUN). It functions as both a transcriptional
  activator and
  repressor depending on context and binding partners. IRF8 is essential for myeloid
  and dendritic cell lineage
  specification, particularly for the development of plasmacytoid DCs (pDCs) and conventional
  DC1s (cDC1s).
  It regulates interferon and TLR signaling pathways and controls MHC class II antigen
  processing genes.
  Loss-of-function mutations cause immunodeficiency with dendritic cell and monocyte
  deficiency.
existing_annotations:
  - term:
      id: GO:0002376
      label: immune system process
    evidence_type: IBA
    original_reference_id: GO_REF:0000033
    review:
      summary: >-
        IRF8 is a key transcription factor for immune system development and function.
        It is essential for
        myeloid and dendritic cell lineage specification [PMID:8861914], regulates
        interferon responses
        [PMID:1460054], and controls genes involved in antigen presentation [deep
        research: Qiu et al. 2024].
        The IBA annotation reflects its well-established role across the IRF family.
      action: ACCEPT
      reason: >-
        IRF8 is a master regulator of immune cell development and function. Knockout
        mice show immunodeficiency
        and deregulated hematopoiesis [PMID:8861914]. Human mutations cause dendritic
        cell immunodeficiency
        [PMID:25122610]. This broad process term appropriately captures IRF8's role.
      supported_by:
        - reference_id: PMID:8861914
          supporting_text: "Mice with a null mutation of ICSBP exhibit two prominent
            phenotypes related to previously described activities of the IRF family.
            The first is enhanced susceptibility to virus infections associated with
            impaired production of IFN(gamma)."
        - reference_id: PMID:25122610
          supporting_text: "Laboratory evaluation revealed a highly unusual myeloid
            compartment, remarkable for the complete absence of CD141 and CD161 monocytes,
            absence of CD11c1 conventional dendritic cells (DCs) and CD11c1/CD1231
            plasmacytoid DCs, and striking granulocytic hyperplasia."

        - reference_id: file:human/IRF8/IRF8-deep-research-falcon.md
          supporting_text: 'model: Edison Scientific Literature'
  - term:
      id: GO:0005634
      label: nucleus
    evidence_type: IBA
    original_reference_id: GO_REF:0000033
    review:
      summary: >-
        IRF8 is a nuclear transcription factor that binds DNA regulatory elements.
        Nuclear localization
        is essential for its function and is well-documented [PMID:25122610, PMID:1460054].
      action: ACCEPT
      reason: >-
        IRF8 functions as a nuclear transcription factor. UniProt confirms nuclear
        localization [ECO:0000269|PubMed:23166356,
        ECO:0000269|PubMed:25122610]. The K108E mutation causes loss of nuclear localization,
        demonstrating
        the importance of nuclear translocation for function.
      supported_by:
        - reference_id: PMID:25122610
          supporting_text: "loss of the positively charged side chain at K108 causes
            loss of nuclear localization and loss of transcriptional activity"

  - term:
      id: GO:0006357
      label: regulation of transcription by RNA polymerase II
    evidence_type: IBA
    original_reference_id: GO_REF:0000033
    review:
      summary: >-
        IRF8 regulates transcription by RNA polymerase II, acting both as an activator
        and repressor of
        target genes including interferon-inducible genes and immune cell differentiation
        genes [PMID:1460054].
      action: ACCEPT
      reason: >-
        IRF8 is a sequence-specific DNA-binding transcription factor that regulates
        Pol II transcription.
        The original 1992 paper established it as a negative regulator of ICS-containing
        promoters.
        It can both activate and repress transcription depending on context.
      supported_by:
        - reference_id: PMID:1460054
          supporting_text: "The results of transient transfection assays carried out
            either in hematopoietic or nonhematopoietic cells suggest that ICSBP acts
            as a negative regulatory factor on ICS-containing promoters."

  - term:
      id: GO:0000981
      label: DNA-binding transcription factor activity, RNA polymerase 
        II-specific
    evidence_type: IBA
    original_reference_id: GO_REF:0000033
    review:
      summary: >-
        IRF8 is a DNA-binding transcription factor with an N-terminal DNA-binding
        domain (IRF tryptophan
        pentad repeat) that binds ISRE, EICE, and AICE regulatory elements [PMID:1460054,
        deep research].
      action: ACCEPT
      reason: >-
        This is a core function of IRF8. The DNA-binding domain is well-characterized
        (amino acids 7-114
        per UniProt). IRF8 binds interferon consensus sequences and regulates Pol
        II transcription.
      supported_by:
        - reference_id: PMID:1460054
          supporting_text: "Truncated ICSBP lacking the first 33 amino-terminal amino
            acids fails to bind to the ICS, indicating that at least part of the DNA
            binding domain is located within the well conserved amino terminus."

  - term:
      id: GO:0000978
      label: RNA polymerase II cis-regulatory region sequence-specific DNA 
        binding
    evidence_type: IBA
    original_reference_id: GO_REF:0000033
    review:
      summary: >-
        IRF8 binds specific DNA sequences including the interferon consensus sequence
        (ICS/ISRE),
        EICE (with PU.1), and AICE (with BATF/JUN) [PMID:1460054, deep research].
      action: ACCEPT
      reason: >-
        Sequence-specific DNA binding is well-established for IRF8. The original cloning
        paper demonstrated
        binding to ICS elements. More recent work shows binding to composite EICE
        and AICE motifs with
        partner transcription factors.
      supported_by:
        - reference_id: PMID:1460054
          supporting_text: "A murine cDNA which encodes an ICS binding protein has
            been reported (M-ICSBP). The cloning of the human homologue of ICSBP (H-ICSBP)
            is described."

  - term:
      id: GO:0000976
      label: transcription cis-regulatory region binding
    evidence_type: IEA
    original_reference_id: GO_REF:0000002
    review:
      summary: >-
        IEA annotation from InterPro mapping. IRF8 binds cis-regulatory regions including
        ISRE, EICE,
        and AICE elements.
      action: ACCEPT
      reason: >-
        This is a parent term of the more specific GO:0000978 (RNA polymerase II cis-regulatory
        region
        sequence-specific DNA binding). The IEA annotation is consistent with IRF8's
        known DNA-binding
        function and supported by IBA annotation to the child term.

  - term:
      id: GO:0000978
      label: RNA polymerase II cis-regulatory region sequence-specific DNA 
        binding
    evidence_type: IEA
    original_reference_id: GO_REF:0000117
    review:
      summary: >-
        IEA annotation from ARBA machine learning models, consistent with IBA annotation
        to the same term.
      action: ACCEPT
      reason: >-
        This duplicates the IBA annotation to GO:0000978. The IEA evidence provides
        additional support
        from computational methods. Both are valid.

  - term:
      id: GO:0003677
      label: DNA binding
    evidence_type: IEA
    original_reference_id: GO_REF:0000120
    review:
      summary: >-
        General DNA binding annotation from combined IEA methods. IRF8 has a well-characterized
        DNA-binding domain (IRF tryptophan pentad repeat, aa 7-114).
      action: ACCEPT
      reason: >-
        This is a parent term of the more specific sequence-specific DNA binding terms.
        While general,
        it is accurate. More specific child terms are also annotated.

  - term:
      id: GO:0003700
      label: DNA-binding transcription factor activity
    evidence_type: IEA
    original_reference_id: GO_REF:0000120
    review:
      summary: >-
        IEA annotation for general transcription factor activity. IRF8 is a DNA-binding
        transcription
        factor that can activate or repress transcription.
      action: ACCEPT
      reason: >-
        This is a parent term of GO:0000981 (DNA-binding transcription factor activity,
        RNA polymerase
        II-specific). Accurate but less specific than the IBA annotation.

  - term:
      id: GO:0005634
      label: nucleus
    evidence_type: IEA
    original_reference_id: GO_REF:0000120
    review:
      summary: >-
        IEA annotation for nuclear localization, consistent with IBA and IDA annotations
        to the same term.
      action: ACCEPT
      reason: >-
        Duplicates IBA annotation. Nuclear localization is well-established for IRF8
        as a transcription factor.

  - term:
      id: GO:0005737
      label: cytoplasm
    evidence_type: IEA
    original_reference_id: GO_REF:0000044
    review:
      summary: >-
        IEA annotation from UniProt subcellular location vocabulary. IRF8 is found
        in cytoplasm in
        resting cells and translocates to nucleus upon IFN-gamma stimulation.
      action: ACCEPT
      reason: >-
        UniProt states IRF8 localizes in the cytoplasm in resting macrophages and
        translocates to the
        nucleus upon IFN-gamma induction. This cytoplasmic localization is accurate
        for unstimulated cells.

  - term:
      id: GO:0006355
      label: regulation of DNA-templated transcription
    evidence_type: IEA
    original_reference_id: GO_REF:0000002
    review:
      summary: >-
        IEA annotation from InterPro. IRF8 regulates transcription as a DNA-binding
        transcription factor.
      action: ACCEPT
      reason: >-
        This is a parent term of GO:0006357 (regulation of transcription by RNA polymerase
        II).
        Consistent with IRF8's core function as a transcription factor.

  - term:
      id: GO:0006914
      label: autophagy
    evidence_type: IEA
    original_reference_id: GO_REF:0000043
    review:
      summary: >-
        IEA annotation based on UniProt keyword mapping. UniProt lists "Autophagy"
        as a keyword based on
        one paper [PMID:29434592] showing IRF8 positively regulates macroautophagy
        in dendritic cells.
        However, IRF8 is a transcription factor that may regulate autophagy gene expression,
        not a
        direct autophagy component.
      action: MARK_AS_OVER_ANNOTATED
      reason: >-
        IRF8 is a transcription factor for immune cell differentiation, not an autophagy
        pathway component.
        The UniProt annotation is based on a single paper showing IRF8 can positively
        regulate autophagy
        in DCs, but this is a downstream effect of its transcription factor activity,
        not a core function.
        The term "autophagy" without qualifier implies direct involvement in the autophagy
        process.
        A more appropriate annotation would be "regulation of autophagy" if warranted.

  - term:
      id: GO:0006955
      label: immune response
    evidence_type: IEA
    original_reference_id: GO_REF:0000117
    review:
      summary: >-
        IEA annotation from ARBA. IRF8 regulates immune responses through its role
        in interferon signaling
        and immune cell development.
      action: ACCEPT
      reason: >-
        IRF8 is critical for immune responses, controlling interferon-inducible gene
        expression and
        immune cell differentiation. This is consistent with the IBA annotation to
        GO:0002376 (immune
        system process).

  - term:
      id: GO:0098542
      label: defense response to other organism
    evidence_type: IEA
    original_reference_id: GO_REF:0000117
    review:
      summary: >-
        IEA annotation from ARBA. IRF8 is important for defense against pathogens
        through its role in
        interferon responses and immune cell development.
      action: KEEP_AS_NON_CORE
      reason: >-
        While IRF8 is important for antimicrobial defense (IRF8 mutations cause mycobacterial
        susceptibility),
        this is a downstream consequence of its role as a transcription factor for
        immune cell development,
        not a direct molecular function. Defense response is a secondary process.
      supported_by:
        - reference_id: PMID:8861914
          supporting_text: "enhanced susceptibility to virus infections associated
            with impaired production of IFN(gamma)"

  - term:
      id: GO:0005515
      label: protein binding
    evidence_type: IPI
    original_reference_id: PMID:21903422
    review:
      summary: >-
        IPI annotation from HI5 interactome mapping study. This was a high-throughput
        proteomics study
        mapping innate immunity protein interactions. IRF8 was one of many proteins
        analyzed.
      action: REMOVE
      reason: >-
        "Protein binding" (GO:0005515) is uninformative without specifying the binding
        partner or
        functional context. The HI5 study was a high-throughput interactome mapping
        that does not
        provide specific functional insights for IRF8. More informative annotations
        for IRF8's
        protein interactions exist (e.g., with PU.1, BATF, JUNB). This vague annotation
        should
        be replaced with specific partner annotations.

      supported_by:
        - reference_id: PMID:21903422
          supporting_text: 2011 Sep 8. Mapping a dynamic innate immunity protein
            interaction network regulating type I interferon production.
  - term:
      id: GO:0005515
      label: protein binding
    evidence_type: IPI
    original_reference_id: PMID:32814053
    review:
      summary: >-
        IPI annotation from a neurodegenerative disease interactome mapping study
        that included
        IRF8 as one of many proteins analyzed via yeast two-hybrid.
      action: REMOVE
      reason: >-
        This high-throughput interactome study focused on neurodegenerative disease
        proteins.
        IRF8 is not a neurodegeneration protein; it is an immune transcription factor.
        The
        "protein binding" annotation from this study provides no meaningful functional
        information
        about IRF8's actual binding partners (PU.1, BATF, JUNB, etc.).

      supported_by:
        - reference_id: PMID:32814053
          supporting_text: Interactome Mapping Provides a Network of 
            Neurodegenerative Disease Proteins and Uncovers Widespread Protein 
            Aggregation in Affected Brains.
  - term:
      id: GO:0000122
      label: negative regulation of transcription by RNA polymerase II
    evidence_type: IEA
    original_reference_id: GO_REF:0000120
    review:
      summary: >-
        IEA annotation for transcriptional repression. IRF8 was originally identified
        as a negative
        regulator of ICS-containing promoters [PMID:1460054].
      action: ACCEPT
      reason: >-
        IRF8 acts as a transcriptional repressor in certain contexts, including repression
        of
        interferon-inducible genes and osteoclast differentiation factors. This is
        well-documented
        experimentally and supported by IDA annotations.
      supported_by:
        - reference_id: PMID:1460054
          supporting_text: "ICSBP acts as a negative regulatory factor on ICS-containing
            promoters"

  - term:
      id: GO:0000977
      label: RNA polymerase II transcription regulatory region sequence-specific
        DNA binding
    evidence_type: IEA
    original_reference_id: GO_REF:0000107
    review:
      summary: >-
        IEA annotation from Ensembl Compara ortholog transfer. IRF8 binds specific
        DNA sequences
        in transcription regulatory regions.
      action: ACCEPT
      reason: >-
        Equivalent to GO:0000978 (RNA polymerase II cis-regulatory region sequence-specific
        DNA binding).
        Consistent with IBA and IDA annotations to related terms. IRF8 binds ISRE,
        EICE, and AICE elements.

  - term:
      id: GO:0002273
      label: plasmacytoid dendritic cell differentiation
    evidence_type: IEA
    original_reference_id: GO_REF:0000107
    review:
      summary: >-
        IEA annotation from ortholog transfer. IRF8 is essential for pDC development,
        as demonstrated
        by loss of pDCs in IRF8-deficient mice and humans [PMID:25122610, file:human/IRF8/IRF8-deep-research-falcon.md].
      action: ACCEPT
      reason: >-
        This is a core function of IRF8. Human patients with IRF8 mutations lack circulating
        pDCs.
        Mouse knockouts also lack pDCs. This is well-supported by both human and mouse
        studies.
      supported_by:
        - reference_id: PMID:25122610
          supporting_text: "Laboratory evaluation revealed a highly unusual myeloid
            compartment, remarkable for the complete absence of CD141 and CD161 monocytes,
            absence of CD11c1 conventional dendritic cells (DCs) and CD11c1/CD1231
            plasmacytoid DCs, and striking granulocytic hyperplasia."

  - term:
      id: GO:0002314
      label: germinal center B cell differentiation
    evidence_type: IEA
    original_reference_id: GO_REF:0000107
    review:
      summary: >-
        IEA annotation from ortholog transfer. IRF8 is expressed in B cells and involved
        in B cell
        development, including germinal center reactions.
      action: KEEP_AS_NON_CORE
      reason: >-
        IRF8 is expressed in B cells and plays roles in B cell biology, but its primary
        functions are
        in myeloid and dendritic cell lineages. B cell differentiation is a secondary
        role. The deep
        research mentions IRF8 involvement in germinal center programs and B cell
        lymphoma antigen
        presentation, but myeloid/DC specification is the core function.

  - term:
      id: GO:0002316
      label: follicular B cell differentiation
    evidence_type: IEA
    original_reference_id: GO_REF:0000107
    review:
      summary: >-
        IEA annotation from ortholog transfer for follicular B cell differentiation.
      action: KEEP_AS_NON_CORE
      reason: >-
        Similar to germinal center B cell differentiation - IRF8 has roles in B cell
        biology but
        its core functions are in myeloid/DC lineage specification. This represents
        a secondary
        function in B cell development.

  - term:
      id: GO:0032479
      label: regulation of type I interferon production
    evidence_type: IEA
    original_reference_id: GO_REF:0000107
    review:
      summary: >-
        IEA annotation from ortholog transfer. IRF8 regulates type I interferon responses
        through
        its role in pDC development (major IFN-I producers) and direct transcriptional
        regulation.
      action: ACCEPT
      reason: >-
        IRF8 is essential for pDC development, and pDCs are the major producers of
        type I interferons.
        Additionally, IRF8 directly regulates interferon-inducible genes. This is
        a well-established function.
      supported_by:
        - reference_id: PMID:1460054
          supporting_text: "The promoter regions of many interferon-inducible genes
            share a short DNA sequence motif, termed the interferon consensus sequence
            (ICS) to which several regulatory proteins bind."

  - term:
      id: GO:0043065
      label: positive regulation of apoptotic process
    evidence_type: IEA
    original_reference_id: GO_REF:0000107
    review:
      summary: >-
        IEA annotation from ortholog transfer for apoptosis regulation.
      action: KEEP_AS_NON_CORE
      reason: >-
        IRF8 has been implicated in apoptosis regulation in some contexts, but this
        is not a core
        function. Its primary roles are in transcriptional regulation of immune cell
        differentiation
        and interferon responses. Apoptosis effects may be secondary consequences.

  - term:
      id: GO:0045944
      label: positive regulation of transcription by RNA polymerase II
    evidence_type: IEA
    original_reference_id: GO_REF:0000120
    review:
      summary: >-
        IEA annotation for transcriptional activation. IRF8 can act as a transcriptional
        activator
        in certain contexts, particularly for immune response genes.
      action: ACCEPT
      reason: >-
        IRF8 functions as both activator and repressor depending on context. UniProt
        states it
        "Can both act as a transcriptional activator or repressor." The K108E mutation
        causes
        loss of transcriptional activity, demonstrating wild-type IRF8 has activator
        function.
      supported_by:
        - reference_id: PMID:25122610
          supporting_text: "Biochemical characterization of the IRF8(K108E) mutant
            in vitro shows that loss of the positively charged side chain at K108
            causes loss of nuclear localization and loss of transcriptional activity"

  - term:
      id: GO:0071346
      label: cellular response to type II interferon
    evidence_type: IEA
    original_reference_id: GO_REF:0000107
    review:
      summary: >-
        IEA annotation from ortholog transfer. IRF8 expression is induced by IFN-gamma
        and it mediates
        IFN-gamma transcriptional responses [PMID:1460054].
      action: ACCEPT
      reason: >-
        IRF8 is induced by IFN-gamma and translocates to the nucleus upon IFN-gamma
        stimulation to
        regulate target genes. IFN treatment alleviates ICSBP-mediated repression.
      supported_by:
        - reference_id: PMID:1460054
          supporting_text: "either interferon-gamma (IFN-gamma) or IFN-beta can alleviate
            the repression mediated by ICSBP"

  - term:
      id: GO:0097028
      label: dendritic cell differentiation
    evidence_type: IEA
    original_reference_id: GO_REF:0000107
    review:
      summary: >-
        IEA annotation from ortholog transfer. IRF8 is essential for dendritic cell
        development,
        particularly cDC1 and pDC lineages [PMID:25122610, deep research].
      action: ACCEPT
      reason: >-
        This is a core function of IRF8. Human IRF8 mutations cause DC deficiency.
        Mouse knockouts
        lack cDC1 and pDC populations. IRF8 programs enhancers for DC lineage specification.
      supported_by:
        - reference_id: PMID:25122610
          supporting_text: "absence of CD11c1 conventional dendritic cells (DCs) and
            CD11c1/CD1231 plasmacytoid DCs"

  - term:
      id: GO:0005654
      label: nucleoplasm
    evidence_type: IDA
    original_reference_id: GO_REF:0000052
    review:
      summary: >-
        IDA annotation from HPA immunofluorescence data. IRF8 localizes to the nucleoplasm
        as a
        transcription factor.
      action: ACCEPT
      reason: >-
        As a DNA-binding transcription factor, IRF8 functions in the nucleoplasm where
        it binds
        chromatin. This is consistent with its molecular function.

  - term:
      id: GO:0005515
      label: protein binding
    evidence_type: IPI
    original_reference_id: PMID:33951726
    review:
      summary: >-
        IPI annotation for protein binding, specifically with PU.1/SPI1. The study
        characterized
        PU.1 mutations in agammaglobulinemia and showed IRF8 interaction with PU.1.
      action: MODIFY
      reason: >-
        While this annotation captures a real interaction, "protein binding" is too
        vague. IRF8
        interacts with PU.1 to bind EICE composite elements and regulate gene expression.
        A more
        specific term like "DNA-binding transcription factor binding" or annotation
        with specific
        interaction context would be more informative.
      proposed_replacement_terms:
        - id: GO:0140297
          label: DNA-binding transcription factor binding

      supported_by:
        - reference_id: PMID:33951726
          supporting_text: May 5. Constrained chromatin accessibility in 
            PU.1-mutated agammaglobulinemia patients.
  - term:
      id: GO:0002273
      label: plasmacytoid dendritic cell differentiation
    evidence_type: ISS
    original_reference_id: GO_REF:0000024
    review:
      summary: >-
        ISS annotation from manual ortholog transfer. pDC differentiation is essential
        function of IRF8.
      action: ACCEPT
      reason: >-
        Duplicates the IEA annotation with different evidence (manual ortholog transfer).
        pDC
        differentiation is a well-established core function of IRF8.

  - term:
      id: GO:0032479
      label: regulation of type I interferon production
    evidence_type: ISS
    original_reference_id: GO_REF:0000024
    review:
      summary: >-
        ISS annotation from manual ortholog transfer. IRF8 regulates type I IFN production.
      action: ACCEPT
      reason: >-
        Duplicates the IEA annotation with different evidence. Type I IFN regulation
        is well-established.

  - term:
      id: GO:0097028
      label: dendritic cell differentiation
    evidence_type: ISS
    original_reference_id: GO_REF:0000024
    review:
      summary: >-
        ISS annotation from manual ortholog transfer. DC differentiation is a core
        IRF8 function.
      action: ACCEPT
      reason: >-
        Duplicates the IEA annotation with different evidence. DC differentiation
        is a core function
        of IRF8 supported by human and mouse genetic evidence.

  - term:
      id: GO:1990837
      label: sequence-specific double-stranded DNA binding
    evidence_type: IDA
    original_reference_id: PMID:28473536
    review:
      summary: >-
        IDA annotation from a systematic study of transcription factor DNA binding
        specificities
        using SELEX. The study examined 542 human TFs including IRF8.
      action: ACCEPT
      reason: >-
        IRF8 binds specific DNA sequences (ISRE, EICE, AICE elements) as double-stranded
        DNA.
        This systematic study provides direct evidence for sequence-specific binding.

      supported_by:
        - reference_id: PMID:28473536
          supporting_text: Impact of cytosine methylation on DNA binding 
            specificities of human transcription factors.
  - term:
      id: GO:0000785
      label: chromatin
    evidence_type: ISA
    original_reference_id: GO_REF:0000113
    review:
      summary: >-
        ISA annotation from TFClass database for transcription factors. IRF8 binds
        chromatin at
        regulatory elements.
      action: ACCEPT
      reason: >-
        As a transcription factor, IRF8 functions at chromatin, binding enhancers
        and promoters.
        Deep research describes IRF8's role in chromatin accessibility and enhancer
        programming.

  - term:
      id: GO:0000981
      label: DNA-binding transcription factor activity, RNA polymerase 
        II-specific
    evidence_type: ISA
    original_reference_id: GO_REF:0000113
    review:
      summary: >-
        ISA annotation from TFClass database. IRF8 is classified as a sequence-specific
        DNA-binding
        transcription factor.
      action: ACCEPT
      reason: >-
        Duplicates IBA annotation. This is a core molecular function of IRF8.

  - term:
      id: GO:0000122
      label: negative regulation of transcription by RNA polymerase II
    evidence_type: IDA
    original_reference_id: PMID:1460054
    review:
      summary: >-
        IDA annotation from the original IRF8/ICSBP cloning paper showing it acts
        as a transcriptional
        repressor of interferon-inducible genes.
      action: ACCEPT
      reason: >-
        The original characterization paper demonstrated that ICSBP/IRF8 acts as a
        negative regulator
        of ICS-containing promoters. This is direct experimental evidence.
      supported_by:
        - reference_id: PMID:1460054
          supporting_text: "The results of transient transfection assays carried out
            either in hematopoietic or nonhematopoietic cells suggest that ICSBP acts
            as a negative regulatory factor on ICS-containing promoters."

  - term:
      id: GO:0000122
      label: negative regulation of transcription by RNA polymerase II
    evidence_type: IDA
    original_reference_id: PMID:25122610
    review:
      summary: >-
        IDA annotation from functional characterization of human IRF8 K108E mutation
        showing
        loss of transcriptional activity.
      action: ACCEPT
      reason: >-
        The study characterized IRF8 function by showing that the K108E mutation causes
        loss of transcriptional activity, demonstrating that wild-type IRF8 has transcriptional
        regulatory function.
      supported_by:
        - reference_id: PMID:25122610
          supporting_text: "Biochemical characterization of the IRF8(K108E) mutant
            in vitro shows that loss of the positively charged side chain at K108
            causes loss of nuclear localization and loss of transcriptional activity"

  - term:
      id: GO:0005634
      label: nucleus
    evidence_type: IDA
    original_reference_id: PMID:25122610
    review:
      summary: >-
        IDA annotation for nuclear localization from the K108E mutation study showing
        IRF8
        requires nuclear localization for function.
      action: ACCEPT
      reason: >-
        Direct experimental evidence for nuclear localization and its importance for
        function.
        The K108E mutation causes loss of nuclear localization.
      supported_by:
        - reference_id: PMID:25122610
          supporting_text: "loss of the positively charged side chain at K108 causes
            loss of nuclear localization and loss of transcriptional activity"

  - term:
      id: GO:0005737
      label: cytoplasm
    evidence_type: IDA
    original_reference_id: PMID:25122610
    review:
      summary: >-
        IDA annotation for cytoplasmic localization in resting cells before IFN-gamma
        stimulation.
      action: ACCEPT
      reason: >-
        IRF8 is found in the cytoplasm in resting cells. The K108E mutation affects
        nuclear
        translocation, indicating normal IRF8 shuttles between cytoplasm and nucleus.

      supported_by:
        - reference_id: PMID:25122610
          supporting_text: Functional characterization of the human dendritic 
            cell immunodeficiency associated with the IRF8(K108E) mutation.
  - term:
      id: GO:0045944
      label: positive regulation of transcription by RNA polymerase II
    evidence_type: IDA
    original_reference_id: PMID:25122610
    review:
      summary: >-
        IDA annotation for transcriptional activation function, demonstrated by loss
        of
        transcriptional activity in K108E mutant.
      action: ACCEPT
      reason: >-
        The K108E mutation study showed loss of transcriptional activity, demonstrating
        that
        wild-type IRF8 can activate transcription.
      supported_by:
        - reference_id: PMID:25122610
          supporting_text: "loss of the positively charged side chain at K108 causes
            loss of nuclear localization and loss of transcriptional activity"

  - term:
      id: GO:0071346
      label: cellular response to type II interferon
    evidence_type: IDA
    original_reference_id: PMID:25122610
    review:
      summary: >-
        IDA annotation for IFN-gamma response, showing IRF8 is involved in interferon-regulated
        transcription.
      action: ACCEPT
      reason: >-
        The study shows IRF8 regulates IRF8-bound and IRF8-regulated transcriptional
        targets
        that are depleted in the patient, demonstrating its role in interferon responses.
      supported_by:
        - reference_id: PMID:25122610
          supporting_text: "depletion of IRF8-bound and IRF8-regulated transcriptional
            targets"

  - term:
      id: GO:0000978
      label: RNA polymerase II cis-regulatory region sequence-specific DNA 
        binding
    evidence_type: IDA
    original_reference_id: PMID:1460054
    review:
      summary: >-
        IDA annotation for sequence-specific DNA binding to the interferon consensus
        sequence (ICS).
      action: ACCEPT
      reason: >-
        The original cloning paper demonstrated that ICSBP binds to ICS elements and
        that truncation
        of the N-terminus eliminates DNA binding.
      supported_by:
        - reference_id: PMID:1460054
          supporting_text: "Truncated ICSBP lacking the first 33 amino-terminal amino
            acids fails to bind to the ICS"

  - term:
      id: GO:0001227
      label: DNA-binding transcription repressor activity, RNA polymerase 
        II-specific
    evidence_type: IDA
    original_reference_id: PMID:1460054
    review:
      summary: >-
        IDA annotation for transcriptional repressor activity based on the original
        cloning paper.
      action: ACCEPT
      reason: >-
        The original paper established ICSBP/IRF8 as a transcriptional repressor of
        ICS-containing
        promoters. This molecular function is well-documented.
      supported_by:
        - reference_id: PMID:1460054
          supporting_text: "ICSBP acts as a negative regulatory factor on ICS-containing
            promoters"

  - term:
      id: GO:0005829
      label: cytosol
    evidence_type: TAS
    original_reference_id: Reactome:R-HSA-1015702
    review:
      summary: >-
        TAS annotation from Reactome pathway for expression of IFN-induced genes.
        IRF8 is present
        in cytosol in unstimulated cells.
      action: ACCEPT
      reason: >-
        Consistent with IDA annotation showing cytoplasmic localization in resting
        cells. Cytosol
        is a subcompartment of cytoplasm.

  - term:
      id: GO:0005829
      label: cytosol
    evidence_type: TAS
    original_reference_id: Reactome:R-HSA-1031716
    review:
      summary: >-
        TAS annotation from Reactome pathway for expression of IFNG-stimulated genes.
      action: ACCEPT
      reason: >-
        Duplicate of above annotation from different Reactome pathway. Cytosolic localization
        is consistent with other evidence.

  - term:
      id: GO:0000122
      label: negative regulation of transcription by RNA polymerase II
    evidence_type: TAS
    original_reference_id: PMID:1460054
    review:
      summary: >-
        TAS annotation for transcriptional repression, citing the original ICSBP cloning
        paper.
      action: ACCEPT
      reason: >-
        This is a duplicate of the IDA annotation to the same term from the same reference.
        The original paper established IRF8 as a transcriptional repressor.

      supported_by:
        - reference_id: PMID:1460054
          supporting_text: Human interferon consensus sequence binding protein 
            is a negative regulator of enhancer elements common to 
            interferon-inducible genes.
  - term:
      id: GO:0000981
      label: DNA-binding transcription factor activity, RNA polymerase 
        II-specific
    evidence_type: TAS
    original_reference_id: PMID:1460054
    review:
      summary: >-
        TAS annotation for transcription factor activity from the original cloning
        paper.
      action: ACCEPT
      reason: >-
        This duplicates IBA and ISA annotations. The original paper established IRF8
        as a
        DNA-binding transcription factor.

      supported_by:
        - reference_id: PMID:1460054
          supporting_text: Human interferon consensus sequence binding protein 
            is a negative regulator of enhancer elements common to 
            interferon-inducible genes.
  - term:
      id: GO:0006955
      label: immune response
    evidence_type: TAS
    original_reference_id: PMID:8861914
    review:
      summary: >-
        TAS annotation for immune response based on the mouse knockout study showing
        immunodeficiency.
      action: ACCEPT
      reason: >-
        The mouse knockout study demonstrated IRF8's essential role in immune function,
        including
        virus susceptibility and impaired IFN-gamma production.
      supported_by:
        - reference_id: PMID:8861914
          supporting_text: "enhanced susceptibility to virus infections associated
            with impaired production of IFN(gamma)"

references:
  - id: GO_REF:0000002
    title: Gene Ontology annotation through association of InterPro records with
      GO terms
    findings: []
  - id: GO_REF:0000024
    title: Manual transfer of experimentally-verified manual GO annotation data 
      to orthologs by curator judgment of sequence similarity
    findings: []
  - id: GO_REF:0000033
    title: Annotation inferences using phylogenetic trees
    findings: []
  - id: GO_REF:0000043
    title: Gene Ontology annotation based on UniProtKB/Swiss-Prot keyword 
      mapping
    findings: []
  - id: GO_REF:0000044
    title: Gene Ontology annotation based on UniProtKB/Swiss-Prot Subcellular 
      Location vocabulary mapping, accompanied by conservative changes to GO 
      terms applied by UniProt
    findings: []
  - id: GO_REF:0000052
    title: Gene Ontology annotation based on curation of immunofluorescence data
    findings: []
  - id: GO_REF:0000107
    title: Automatic transfer of experimentally verified manual GO annotation 
      data to orthologs using Ensembl Compara
    findings: []
  - id: GO_REF:0000113
    title: Gene Ontology annotation of human sequence-specific DNA binding 
      transcription factors (DbTFs) based on the TFClass database
    findings: []
  - id: GO_REF:0000117
    title: Electronic Gene Ontology annotations created by ARBA machine learning
      models
    findings: []
  - id: GO_REF:0000120
    title: Combined Automated Annotation using Multiple IEA Methods
    findings: []
  - id: PMID:1460054
    title: Human interferon consensus sequence binding protein is a negative 
      regulator of enhancer elements common to interferon-inducible genes.
    findings:
      - statement: IRF8/ICSBP binds to the interferon consensus sequence (ICS)
      - statement: Acts as a transcriptional repressor of ICS-containing 
          promoters
      - statement: DNA binding requires the N-terminal domain
      - statement: Expressed in hematopoietic cells
      - statement: IFN treatment alleviates repression
  - id: PMID:21903422
    title: Mapping a dynamic innate immunity protein interaction network 
      regulating type I interferon production.
    findings:
      - statement: High-throughput interactome mapping study (HI5)
      - statement: IRF8 was one of many proteins analyzed
      - statement: Study focused on innate immunity network
  - id: PMID:25122610
    title: Functional characterization of the human dendritic cell 
      immunodeficiency associated with the IRF8(K108E) mutation.
    findings:
      - statement: K108E mutation causes loss of nuclear localization
      - statement: K108E mutation causes loss of transcriptional activity
      - statement: IRF8 localizes to cytoplasm in resting cells
      - statement: IRF8 translocates to nucleus upon IFN-gamma stimulation
      - statement: K108E causes increased ubiquitination and proteasomal 
          degradation
      - statement: Loss of both activator and repressor functions in mutant
  - id: PMID:28473536
    title: Impact of cytosine methylation on DNA binding specificities of human 
      transcription factors.
    findings:
      - statement: Systematic SELEX study of 542 human TFs
      - statement: Determined DNA binding specificities
      - statement: IRF8 included in the analysis
  - id: PMID:32814053
    title: Interactome Mapping Provides a Network of Neurodegenerative Disease 
      Proteins and Uncovers Widespread Protein Aggregation in Affected Brains.
    findings:
      - statement: High-throughput interactome study focused on 
          neurodegeneration
      - statement: IRF8 was one of many proteins in the network
      - statement: Not specifically relevant to IRF8 core function
  - id: PMID:33951726
    title: Constrained chromatin accessibility in PU.1-mutated 
      agammaglobulinemia patients.
    findings:
      - statement: IRF8 interacts with PU.1/SPI1
      - statement: PU.1 and IRF8 cooperate in chromatin accessibility
      - statement: Important for B cell development
  - id: PMID:8861914
    title: Immunodeficiency and chronic myelogenous leukemia-like syndrome in 
      mice with a targeted mutation of the ICSBP gene.
    findings:
      - statement: IRF8/ICSBP knockout mice have immunodeficiency
      - statement: Enhanced susceptibility to viral infections
      - statement: Impaired IFN-gamma production
      - statement: Deregulated hematopoiesis with CML-like syndrome
  - id: Reactome:R-HSA-1015702
    title: Expression of IFN-induced genes
    findings: []
  - id: Reactome:R-HSA-1031716
    title: Expression of IFNG-stimulated genes
    findings: []
  - id: file:human/IRF8/IRF8-deep-research-falcon.md
    title: Deep research report on IRF8
    findings: []

core_functions:
  - molecular_function:
      id: GO:0000981
      label: DNA-binding transcription factor activity, RNA polymerase 
        II-specific
    description: >-
      IRF8 is a sequence-specific DNA-binding transcription factor that binds ISRE,
      EICE, and AICE
      regulatory elements to control gene expression.
  - molecular_function:
      id: GO:0001227
      label: DNA-binding transcription repressor activity, RNA polymerase 
        II-specific
    description: >-
      IRF8 acts as a transcriptional repressor of interferon-inducible genes, maintaining
      submaximal
      activity that can be relieved by interferon treatment.
    directly_involved_in:
      - id: GO:0097028
        label: dendritic cell differentiation
  - molecular_function:
      id: GO:0000981
      label: DNA-binding transcription factor activity, RNA polymerase 
        II-specific
    description: >-
      IRF8 is essential for the development of conventional DC1 (cDC1) and plasmacytoid
      DC (pDC)
      populations. Human and mouse deficiency causes absence of these cell types.
    directly_involved_in:
      - id: GO:0002273
        label: plasmacytoid dendritic cell differentiation
  - molecular_function:
      id: GO:0000981
      label: DNA-binding transcription factor activity, RNA polymerase 
        II-specific
    description: >-
      IRF8 is required for pDC development, the major producers of type I interferons.
    directly_involved_in:
      - id: GO:0032479
        label: regulation of type I interferon production
  - molecular_function:
      id: GO:0000981
      label: DNA-binding transcription factor activity, RNA polymerase 
        II-specific
    description: >-
      IRF8 mediates cellular responses to IFN-gamma by translocating to the nucleus
      and
      regulating target gene expression.
    directly_involved_in:
      - id: GO:0071346
        label: cellular response to type II interferon

proposed_new_terms: []

suggested_questions:
  - question: What are the specific enhancer elements and chromatin 
      accessibility changes controlled by IRF8 in human DC progenitors?
  - question: How do IRF8 interactions with different partners (PU.1 vs BATF) 
      determine activator vs repressor function?
  - question: What is the relationship between IRF8 and MHC class II antigen 
      processing gene regulation in human DCs?

suggested_experiments:
  - description: ChIP-seq analysis of IRF8 binding sites in human 
      monocyte-derived DCs with and without IFN-gamma stimulation
  - description: CRISPR screens in human hematopoietic progenitors to identify 
      IRF8-dependent genes for DC differentiation
  - description: Structural studies of IRF8-DNA-partner complexes to understand 
      composite element recognition