ZNF207

ZNF207/BuGZ is a multifunctional intrinsically disordered zinc-finger protein that acts principally as a mitotic regulator coupling kinetochore assembly, spindle matrix formation, and liquid-liquid phase separation (LLPS) (PMID:24462186, PMID:24462187, PMID:29074706, PMID:29263080). Through its conserved GLEBS domain it directly binds and stabilizes Bub3 and loads onto kinetochores ahead of Bub1 and BubR1, with pre-kinetochore Bub3 found complexed with BuGZ rather than Bub1/BubR1; this early Bub3 loading then licenses Bub1 and BubR1 recruitment, supports Bub1-dependent centromeric H2A phosphorylation and kinetochore Aurora B activity, and is required for chromosome congression (PMID:24462186, PMID:24462187, PMID:32820050). Its disordered region drives coacervation that concentrates tubulin to build the spindle matrix and promote microtubule assembly, a property phylogenetically conserved alongside mitotic function across diverse eukaryotic homologs (PMID:29074706, PMID:29263080, PMID:34984754). BuGZ also activates Aurora A: its two zinc fingers bind the Aurora A kinase domain and incorporate the kinase into coacervates, enhancing Aurora A LLPS at centrosomes and supporting centrosome maturation, separation, and spindle-pole function (PMID:29074706, PMID:38746663). A cysteine (Cys54) within the second zinc finger of its microtubule-targeting region is covalently modified by parthenolide, which blocks kinetochore-microtubule attachment and chromosome congression (PMID:40425854). Beyond mitosis, ZNF207 has nuclear gene-regulatory roles: its zinc-finger domain interacts with U1 snRNP components to broadly regulate alternative splicing, including canonical LMNA splicing where depletion reduces progerin (PMID:41475346, PMID:40568141); a distinct isoform partners with OCT4/SOX2/NANOG at the OCT4 enhancer to control pluripotency and ectoderm commitment (PMID:30349051); and it binds chromatin to repress transcription, as shown for cat-3 in Neurospora (PMID:35666721). In cancer cells it associates with SETD1A at promoters and enhancers to support leukemia proliferation (PMID:37535603), transcriptionally drives glycolytic genes ENO1 and GAPDH (PMID:40684964), and facilitates PRDX1 K67 lactylation to activate NRF2 and confer ferroptosis resistance (PMID:40680452).

1. 2014 High

   Established BuGZ/ZNF207 as a core kinetochore factor by showing it directly binds and stabilizes Bub3 through its GLEBS domain and uses a separate microtubule-binding domain to load Bub3 onto kinetochores for chromosome alignment.

   Evidence Mitotic regulator screen with domain dissection, direct binding assays, and kinetochore/chromosome alignment readouts in human cells

   PMID:24462186 PMID:24462187

   Open questions at the time

   • Did not define how the microtubule-binding and GLEBS activities are coordinated
   • Structural basis of the GLEBS-Bub3 interface not resolved
2. 2014 High

   Connected BuGZ loss to downstream spindle assembly checkpoint signaling, showing depletion strips both Bub3 and Bub1 from kinetochores and attenuates Bub1-dependent H2A phosphorylation and Aurora B activity.

   Evidence RNAi in human GBM cells with kinetochore immunofluorescence, phospho-H2A staining, Aurora B activity assay, and congression analysis

   PMID:24462187

   Open questions at the time

   • Whether effects are solely via Bub3 loading versus additional substrates unresolved
   • Did not address non-mitotic consequences of depletion
3. 2017 High

   Revealed that BuGZ coacervation is mechanistically coupled to spindle assembly, concentrating tubulin within condensates and activating Aurora A by incorporating the kinase into coacervates.

   Evidence In vitro phase-separation and Aurora A activation assays with coacervation-defective mutants, Xenopus egg extracts, and zinc-finger binding mutants

   PMID:29074706 PMID:29263080

   Open questions at the time

   • Spindle matrix assembly via LLPS validated mainly in vitro
   • Quantitative contribution of LLPS to in vivo spindle function not isolated
4. 2018 Medium

   Extended ZNF207 function beyond mitosis by showing a distinct isoform partners with OCT4/SOX2/NANOG at the OCT4 enhancer to govern pluripotency and ectoderm commitment.

   Evidence OCT4 enhancer pulldown proteomics, Co-IP, and isoform-specific knockdown/rescue with differentiation assays in human ES cells

   PMID:30349051

   Open questions at the time

   • Molecular determinants of isoform switching not defined
   • Direct DNA-binding versus adaptor role at the enhancer unclear
5. 2020 High

   Clarified the temporal logic of kinetochore assembly, showing BuGZ loads via its core GLEBS domain ahead of Bub1/BubR1 and that pre-kinetochore Bub3 is complexed with BuGZ alone.

   Evidence GLEBS mutant series, live-cell recruitment kinetics, and size-exclusion chromatography of Bub3 complexes under varied SAC conditions

   PMID:32820050

   Open questions at the time

   • Trigger for BuGZ release from kinetochores not defined
   • How BuGZ-Bub3 hand-off to Bub1/BubR1 is regulated unknown
6. 2022 Medium

   Demonstrated that LLPS is an evolutionarily conserved, selected-for feature of BuGZ rather than an in vitro artifact, with six divergent homologs retaining both phase separation and mitotic function.

   Evidence Comparative sequence analysis with in vitro LLPS and mitotic functional assays across six eukaryotic homologs

   PMID:34984754

   Open questions at the time

   • Does not establish which condensate clients are conserved
   • Sequence determinants of conserved LLPS not pinpointed
7. 2022 Medium

   Uncovered a chromatin-repressive role, showing BuGZ binds cat-3 chromatin in Neurospora and represses transcription by hindering activator and NC2 recruitment, with zinc fingers required for repression but not DNA binding.

   Evidence GLEBS mutants, ChIP, Co-IP, and cat-3 expression/machinery recruitment assays under oxidative stress in Neurospora crassa

   PMID:35666721

   Open questions at the time

   • Conservation of cat-3 repression to mammalian targets unestablished
   • How DNA-independent chromatin binding is achieved unknown
8. 2023 Medium

   Linked BuGZ to a histone methyltransferase complex, showing the SETD1A FLOS domain binds BuGZ/BUB3 and that GLEBS and IDR are both required for SETD1A binding and leukemia proliferation.

   Evidence FLOS domain binding screen, Co-IP, ChIP-seq, and BuGZ domain mutants with leukemia proliferation assays

   PMID:37535603

   Open questions at the time

   • Functional consequence of BuGZ on SETD1A methyltransferase activity not defined
   • Target genes mediating proliferation not enumerated
9. 2023 Medium

   Showed interphase BuGZ condensation drives tissue regeneration, forming age- and injury-associated nuclear condensates in Drosophila ISCs that promote proliferation and gut repair via YT521-B.

   Evidence Live imaging of condensates, RNAi, proliferation/repair assays, and Co-IP with m6A machinery in Drosophila ISCs

   PMID:37872148

   Open questions at the time

   • Mammalian relevance of interphase condensation untested
   • How m6A machinery controls coacervation mechanistically unclear
10. 2024 Medium

    Refined the Aurora A relationship to a centrosomal axis, showing BuGZ enhances Aurora A LLPS to support centrosome maturation, separation, and spindle-pole function.

    Evidence In vitro LLPS assays, Aurora A IDR/N-C mutants, Co-IP, and centrosome maturation/separation assays with live imaging

    PMID:38746663

    Open questions at the time

    • Stoichiometry of BuGZ-Aurora A in centrosomal condensates unknown
    • Separation of mitotic spindle versus centrosome roles incomplete
11. 2025 High

    Identified a druggable covalent site, showing parthenolide modifies Cys54 in the second zinc finger to block kinetochore-microtubule attachment without acting as a direct microtubule agent.

    Evidence Click-chemistry quantitative MS, covalent binding assays, kinetochore-MT attachment and congression imaging in human cells

    PMID:40425854

    Open questions at the time

    • How Cys54 modification mechanistically disrupts attachment not defined
    • Effect on non-mitotic ZNF207 functions untested
12. 2025 High

    Defined a splicing-regulatory function, showing the zinc-finger domain interacts with U1 snRNP to broadly shape alternative splicing, including LMNA where depletion lowers progerin.

    Evidence CRASP-seq, depletion in progeria patient-derived cells, zinc-finger mutagenesis, and direct U1 snRNP interaction assays

    PMID:40568141 PMID:41475346

    Open questions at the time

    • Genome-wide splicing target spectrum not fully mapped
    • Mechanism of U1 recruitment specificity unresolved
13. 2025 Medium

    Implicated ZNF207 in cancer metabolic and stress-resistance programs, transcriptionally driving glycolytic genes and facilitating PRDX1 K67 lactylation to activate NRF2 and confer ferroptosis/regorafenib resistance.

    Evidence ChIP and dual-luciferase reporters for ENO1/GAPDH plus CRISPR screen with PRDX1 K67 mutant and ferroptosis rescue in HCC cells

    PMID:40680452 PMID:40684964

    Open questions at the time

    • Whether glycolytic and lactylation roles are mechanistically linked unknown
    • How ZNF207 facilitates lactylation enzymatically not defined

• How a single intrinsically disordered zinc-finger protein partitions among its mitotic, splicing, chromatin-repressive, pluripotency, and cancer-metabolic functions — and whether LLPS is the common organizing principle across them — remains unresolved.
• No unified model linking isoform/domain usage to functional outcome
• Tissue- and context-specific partner switching not systematically mapped