Affinage

MIS12

Protein MIS12 homolog · UniProt Q9H081

Length
205 aa
Mass
24.1 kDa
Annotated
2026-04-28
29 papers in source corpus 17 papers cited in narrative 18 extracted findings

Mechanistic narrative

Synthesis pass · prose summary of the discoveries below

MIS12 is the central organizing subunit of the tetrameric MIS12 complex (with DSN1, NSL1/KIAA1570, PMF1/NNF1), which serves as the principal structural bridge between the inner centromere-proximal kinetochore and the outer microtubule-binding KMN network during chromosome segregation. The ~22 nm elongated MIS12 complex binds CENP-C and CENP-T at its inner face—connections regulated by Aurora B phosphorylation of DSN1 to relieve an auto-inhibitory conformation—and uses NSL1 as a scaffold to recruit the NDC80 and KNL1 complexes via RWD-domain interactions, allosterically enhancing Ndc80 microtubule-binding affinity without contacting microtubules itself (PMID:27881301, PMID:20819937, PMID:26430240, PMID:24530301). Dynamic phosphorylation of MIS12-Ser177 by NEK2A expands the fibrous corona for initial microtubule capture in prometaphase, while PP1-mediated dephosphorylation compacts the kinetochore for stable end-on attachment (PMID:40560426). At the transcript level, METTL3-mediated m6A modification stabilizes MIS12 mRNA through the IGF2BP2 reader, linking epitranscriptomic regulation to MIS12 protein abundance and cellular senescence (PMID:33035345).

Mechanistic history

Synthesis pass · year-by-year structured walk · 11 steps
  1. 2003 High

    Establishing that MIS12 is a kinetochore protein required for chromosome alignment answered the fundamental question of where and why this gene acts during mitosis.

    Evidence RNAi depletion in HeLa cells with immunofluorescence and live imaging showing misalignment and lagging chromosomes

    PMID:12515822

    Open questions at the time
    • Binding partners and complex composition unknown
    • Mechanism of kinetochore targeting not determined
  2. 2004 High

    Identification of a multi-subunit MIS12 interactome (including HEC1, Zwint-1, PMF1, HP1α/γ) revealed that MIS12 operates as a hub connecting centromeric heterochromatin to outer kinetochore components.

    Evidence Co-immunoprecipitation and mass spectrometry in HeLa cells, HP1 double RNAi abolishing MIS12 kinetochore localization

    PMID:15502821

    Open questions at the time
    • Stoichiometry and minimal complex composition not resolved
    • Direct versus bridged interactions not distinguished
  3. 2006 High

    Reconstitution of a defined four-subunit MIS12 complex (MIS12, DSN1, PMF1, NSL1) established the minimal functional unit and showed it is required for recruitment of outer kinetochore components including NDC80/HEC1.

    Evidence Bacterial co-expression, mitotic extract fractionation, RNAi in human and chicken DT40 cells

    PMID:16585270

    Open questions at the time
    • Structural architecture of the complex unknown
    • How MIS12 complex connects to inner kinetochore not resolved
  4. 2010 High

    Structural and biochemical dissection revealed the elongated ~22 nm shape of the MIS12 complex and identified NSL1 as the scaffold bridging NDC80 and KNL1 complexes, defining MIS12 complex topology within the KMN network.

    Evidence Negative-stain EM, cross-linking mass spectrometry, biochemical reconstitution

    PMID:20819937

    Open questions at the time
    • Atomic-resolution structure lacking
    • CENP-C binding interface not mapped
  5. 2011 High

    Discovery that CENP-C directly binds the MIS12 complex through a conserved N-terminal motif answered how the inner kinetochore physically connects to the outer KMN network.

    Evidence In vitro binding assays and dominant-negative CENP-C fragment expression in HeLa cells

    PMID:21353556

    Open questions at the time
    • Structural basis of the CENP-C–MIS12 interface unresolved
    • Regulatory mechanism controlling this interaction unknown
  6. 2014 High

    Demonstration that RWD domains of KNL1 bind the MIS12 complex, together with 3D EM of the KMN network, established MIS12 as the central interaction hub organizing outer kinetochore topology.

    Evidence Biochemical interaction assays and 3D EM reconstruction of the KMN network

    PMID:24530301

    Open questions at the time
    • Allosteric consequences of hub assembly on microtubule binding not yet tested
  7. 2015 High

    Single-molecule reconstitution showed the MIS12 (MIND) complex allosterically enhances Ndc80 microtubule-binding affinity fourfold without contacting microtubules itself, revealing a non-obvious activation mechanism.

    Evidence Single-molecule microtubule-binding assays with purified budding yeast complexes

    PMID:26430240

    Open questions at the time
    • Structural basis of allosteric activation not determined
    • Whether human MIS12 complex has identical quantitative effect untested
  8. 2016 High

    Crystal structures of the human MIS12 complex bound to CENP-C revealed atomic-level architecture and showed Aurora B phosphorylation of DSN1 regulates the CENP-C interaction, providing the structural and regulatory logic of inner–outer kinetochore coupling.

    Evidence X-ray crystallography, in vitro kinase assays, mutagenesis, and cell-based assays

    PMID:27881301

    Open questions at the time
    • Full-length complex structure with all binding partners not obtained
    • How phosphorylation dynamics are temporally controlled in vivo unclear
  9. 2020 High

    Epitranscriptomic regulation of MIS12 was established: METTL3-deposited m6A marks on MIS12 mRNA are read by IGF2BP2 to stabilize the transcript, linking RNA modification to kinetochore protein abundance and cellular senescence.

    Evidence m6A profiling, METTL3 KO/overexpression, IGF2BP2 reader identification, mRNA stability assays in human mesenchymal stem cells

    PMID:33035345

    Open questions at the time
    • Which specific m6A sites on MIS12 mRNA are functionally critical not mapped
    • Whether this regulation operates in mitotic cells beyond stem cell senescence unknown
  10. 2024 Medium

    A positive feedback loop was uncovered in which CENP-C binding to MIS12 complex recruits Aurora B, and Aurora B reinforces the CENP-C–MIS12 interaction, ensuring error correction and biorientation; simultaneously, CENP-T was shown to engage MIS12 complex through three phospho-regulated binding surfaces, establishing dual inner-kinetochore receptor logic.

    Evidence CENP-C mutant cell lines with Aurora B localization assays; AlphaFold2 predictions validated by biochemical binding and DT40 genetic analysis

    PMID:39433344 PMID:39628583

    Open questions at the time
    • Quantitative contribution of CENP-T versus CENP-C pathways to MIS12 recruitment in different organisms not resolved
    • How Aurora B feedback is terminated upon biorientation unclear
  11. 2025 High

    Phosphorylation of MIS12-Ser177 by NEK2A was shown to expand the fibrous corona for initial microtubule capture, with PP1 dephosphorylation compacting the kinetochore for stable end-on attachment—establishing MIS12 as a direct regulatory target controlling kinetochore structural dynamics.

    Evidence Phosphosite mapping, in vitro NEK2A kinase assay, phospho-specific antibody, PP1 functional assay, super-resolution imaging in human cells

    PMID:40560426

    Open questions at the time
    • Structural mechanism by which Ser177 phosphorylation causes corona expansion not determined
    • Whether other MIS12 phosphosites cooperate with Ser177 untested

Open questions

Synthesis pass · forward-looking unresolved questions
  • A complete atomic model of the MIS12 complex simultaneously engaged with CENP-C, CENP-T, NDC80, and KNL1 in the context of the full kinetochore is still lacking, and the interplay between DSN1 auto-inhibition relief, MIS12-Ser177 phosphorylation, and Aurora B feedback in dictating kinetochore maturation timing remains to be dissected.
  • No full reconstituted kinetochore structure with all MIS12 complex interfaces resolved
  • Temporal coordination of NEK2A, Aurora B, and PP1 phospho-regulation on MIS12 complex not integrated
  • In vivo stoichiometry of CENP-C vs CENP-T pathways for MIS12 recruitment unclear

Mechanism profile

Synthesis pass · controlled-vocabulary classification · explore literature graph →
Molecular activity
GO:0005198 structural molecule activity 3 GO:0098772 molecular function regulator activity 2
Localization
GO:0005694 chromosome 4 GO:0005654 nucleoplasm 1
Pathway
R-HSA-1640170 Cell Cycle 3 R-HSA-4839726 Chromatin organization 2
Partners
CENP-CCENP-TDSN1IGF2BP2KNL1NEK2ANSL1PMF1
Complex memberships
KMN networkMIS12 complex (MIS12/DSN1/NSL1/PMF1)

Evidence

Reading pass · 18 per-paper findings extracted from the source corpus
Year Finding Method Journal Conf PMIDs
2003 hMis12 localizes to the kinetochore region and is required for equal chromosome segregation; RNAi depletion causes misaligned metaphase chromosomes, lagging anaphase chromosomes, and extended metaphase spindle length, while kinetochore localization of hMis12 is independent of CENP-A loading pathway. RNAi depletion in HeLa cells, immunofluorescence, live imaging The Journal of cell biology High 12515822
2004 Human Mis12 forms a core complex with nine binding partners including HEC1, Zwint-1, c20orf172, DC8, PMF1, and KIAA1570, and also stably associates with centromeric heterochromatin proteins HP1α and HP1γ; double RNAi of HP1 abolishes kinetochore localization of hMis12 and DC8, indicating HP1 anchors the Mis12 complex at centromeric heterochromatin. Co-immunoprecipitation, mass spectrometry, RNAi in HeLa cells, immunofluorescence Nature cell biology High 15502821
2006 A stable four-subunit human Mis12 complex (hMis12, hDsn1, hNnf1/PMF1, hNsl1) is required for kinetochore assembly; depletion reduces outer kinetochore Ndc80/HEC1 localization, diminishes CENP-A, CENP-H, BubR1, and CENP-E levels at kinetochores, causes chromosome misalignment and reduced centromere stretch. Bacterial co-expression, mitotic extract fractionation, RNAi in human and chicken DT40 cells, immunofluorescence The Journal of cell biology High 16585270
2010 The human MIS12 complex has an elongated structure (~22 nm long axis) and the NSL1 subunit acts as a scaffold that supports interactions of the MIS12 complex with both the NDC80 and KNL1 complexes within the KMN network. Biochemical analysis, cross-linking mass spectrometry, negative-stain electron microscopy The Journal of cell biology High 20819937
2010 Human Hsp90-Sgt1 chaperone complex interacts with and stabilizes the Mis12 complex; inhibition of Hsp90 or Sgt1 destabilizes Mis12 complex and delays chromosome alignment by impairing kinetochore microtubule-binding site formation. Co-inhibition of Sgt1 and Skp1 increases Mis12 at kinetochores, suggesting a balance of Mis12 assembly and turnover is required. Co-immunoprecipitation, Hsp90/Sgt1 inhibition, siRNA depletion, immunofluorescence in human cells The Journal of cell biology Medium 20404110
2011 A conserved N-terminal motif of CENP-C directly binds the Mis12 complex with high affinity, linking the inner kinetochore (CCAN) to the outer kinetochore (KMN network); expression of the isolated CENP-C N-terminal segment in HeLa cells prevents outer kinetochore assembly and causes chromosome missegregation and spindle assembly checkpoint impairment. In vitro binding assays, HeLa cell expression of dominant-negative CENP-C fragment, immunofluorescence, checkpoint assays Current biology : CB High 21353556
2014 RWD domains of Knl1 bind the Mis12 complex and mediate kinetochore targeting of Knl1; the KMN network 3D EM structure shows that RWD domain-containing proteins Spc24, Spc25, and Knl1 all use the Mis12 complex as a central interaction hub for outer kinetochore topology. Biochemical interaction assays, 3D electron microscopy structure of KMN network Molecular cell High 24530301
2015 The budding yeast MIND (Mis12) complex enhances microtubule-binding affinity of a single Ndc80 complex by fourfold in a single-molecule assay; MIND does not bind microtubules itself but binds Ndc80 far from the microtubule-binding domain to allosterically activate microtubule interaction, and this activation is redundant with a Ndc80 mutation that may alter its folded conformation. Single-molecule microtubule-binding assays, biochemical binding studies, yeast genetics Proceedings of the National Academy of Sciences of the United States of America High 26430240
2016 Crystal structures of human MIS12 complex bound to a CENP-C fragment reveal the structural basis for MIS12C's bridging function between the KMN network and chromosome-proximal kinetochore; Aurora B kinase phosphorylates Dsn1 within MIS12C to regulate the CENP-C interaction and strengthen inner-outer kinetochore connectivity. X-ray crystallography, in vitro kinase assays, mutagenesis, cell-based functional assays Cell High 27881301
2016 Cep57 localizes to kinetochores and directly binds Mis12 (a KMN network component) as well as Mad1; depletion of Cep57 reduces kinetochore localization of Mad1-Mad2 and impairs spindle assembly checkpoint signaling, while Cep57's microtubule-binding activity mediates timely removal of Mad1 from kinetochores. Co-immunoprecipitation, siRNA depletion, immunofluorescence, checkpoint signaling assays in human cells Nature communications Medium 26743940
2018 In living human interphase cells, hMis12, Nsl1, Dsn1, and Nnf1 form a complex in the nucleoplasm outside centromeres, and at least hMis12 in this soluble pool associates with the CENP-C/H/I/K/M/T/W/N/L complex, as measured by fluorescence cross-correlation spectroscopy. Fluorescence cross-correlation spectroscopy (FCCS) in living human cells PloS one Medium 29509805
2020 METTL3-mediated m6A methylation of MIS12 mRNA stabilizes the transcript through recognition by the m6A reader IGF2BP2; loss of m6A modifications accelerates MIS12 mRNA turnover and reduces MIS12 protein, leading to accelerated human mesenchymal stem cell senescence. m6A transcriptome profiling, METTL3 knockout/overexpression, IGF2BP2 reader assay, mRNA stability assay in human cells Nucleic acids research High 33035345
2020 In mouse oocytes, Mis12 localizes to the cytoplasm and spindle poles (not kinetochores) and is required for G2/M transition by regulating cyclin B1 accumulation through a Cdc14B-APC/CCdh1 pathway; depletion impairs GVBD, rescued by cyclin B1 overexpression or Cdc14B/Cdh1 depletion, while kinetochore functions appear dispensable for meiotic progression. Morpholino/siRNA depletion in mouse oocytes, rescue experiments with cyclin B1 overexpression and Cdc14B/Cdh1 depletion, immunofluorescence Development (Cambridge, England) Medium 32341029
2024 FTO stabilizes MIS12 protein in vascular smooth muscle cells through a proteasome-mediated pathway; FTO upregulation prevents ox-LDL-induced VSMC senescence and cell cycle arrest by maintaining MIS12 protein levels. FTO overexpression/knockdown in primary VSMCs, proteasome inhibitor experiments, Western blotting, SA-β-gal assay Journal of inflammation research Low 38523689
2024 CENP-C binding to the Mis12 complex facilitates centromeric recruitment of Aurora B, and Aurora B in turn reinforces the CENP-C-Mis12C interaction, creating a positive regulatory loop that ensures kinetochore-microtubule error correction and chromosome biorientation. CENP-C mutant cell lines lacking Mis12C-binding region, Aurora B localization assays, chromosome segregation analysis in human RPE-1 and mouse cells Life science alliance Medium 39433344
2024 CENP-T interacts with the Mis12 complex through three binding surfaces; this interaction is cooperatively regulated by dual phosphorylation of Dsn1 (Mis12C component) and CENP-T, ensuring robust Mis12C recruitment to CENP-T and proper mitotic progression. AlphaFold2 structure prediction, biochemical binding assays, mutagenesis, DT40 cells lacking CENP-C-Mis12C interaction, cell biological analysis iScience Medium 39628583
2025 MIS12 is phosphorylated at Ser177 by NEK2A from prophase to prometaphase, which expands the fibrous corona (outer kinetochore projection) to facilitate microtubule attachment; PP1 dephosphorylates Ser177 upon chromosome alignment to promote kinetochore compaction and end-on attachment conversion. Phosphosite mapping, in vitro kinase assay with NEK2A, phospho-specific antibody, PP1 functional assay, super-resolution imaging of fibrous corona in human cells Molecular biology of the cell High 40560426
2025 In budding yeast, α-helical C-terminal motifs of Mtw1 complex subunits Dsn1, Mtw1, and Nnf1 bind Knl1c and Ndc80c; an N-terminal auto-inhibitory segment of Dsn1 occludes binding sites for inner kinetochore subunits CENP-C/Mif2 and CENP-U/Ame1, and Aurora B/Ipl1 phosphorylation of this segment releases auto-inhibition to strengthen inner-outer kinetochore connections. Cryo-EM structure determination, biochemical binding assays, genetic experiments in S. cerevisiae bioRxivpreprint Medium

Source papers

Stage 0 corpus · 29 papers · ranked by NIH iCite citations
Year Title Journal Citations PMID
2004 A conserved Mis12 centromere complex is linked to heterochromatic HP1 and outer kinetochore protein Zwint-1. Nature cell biology 222 15502821
2011 Direct binding of Cenp-C to the Mis12 complex joins the inner and outer kinetochore. Current biology : CB 219 21353556
2003 Human centromere chromatin protein hMis12, essential for equal segregation, is independent of CENP-A loading pathway. The Journal of cell biology 201 12515822
2010 The MIS12 complex is a protein interaction hub for outer kinetochore assembly. The Journal of cell biology 190 20819937
2006 The human Mis12 complex is required for kinetochore assembly and proper chromosome segregation. The Journal of cell biology 178 16585270
1999 Proper metaphase spindle length is determined by centromere proteins Mis12 and Mis6 required for faithful chromosome segregation. Genes & development 178 10398680
2020 METTL3 counteracts premature aging via m6A-dependent stabilization of MIS12 mRNA. Nucleic acids research 154 33035345
2016 Structure of the MIS12 Complex and Molecular Basis of Its Interaction with CENP-C at Human Kinetochores. Cell 131 27881301
2014 Modular assembly of RWD domains on the Mis12 complex underlies outer kinetochore organization. Molecular cell 107 24530301
2003 An Mtw1 complex promotes kinetochore biorientation that is monitored by the Ipl1/Aurora protein kinase. Developmental cell 96 14602074
2010 Molecular architecture and connectivity of the budding yeast Mtw1 kinetochore complex. Journal of molecular biology 51 21075115
2010 Hsp90-Sgt1 and Skp1 target human Mis12 complexes to ensure efficient formation of kinetochore-microtubule binding sites. The Journal of cell biology 49 20404110
2005 Characterization of a Mis12 homologue in Arabidopsis thaliana. Chromosome research : an international journal on the molecular, supramolecular and evolutionary aspects of chromosome biology 37 16331414
2015 Regulation of outer kinetochore Ndc80 complex-based microtubule attachments by the central kinetochore Mis12/MIND complex. Proceedings of the National Academy of Sciences of the United States of America 35 26430240
2016 Cep57 is a Mis12-interacting kinetochore protein involved in kinetochore targeting of Mad1-Mad2. Nature communications 27 26743940
2011 CaMtw1, a member of the evolutionarily conserved Mis12 kinetochore protein family, is required for efficient inner kinetochore assembly in the pathogenic yeast Candida albicans. Molecular microbiology 27 21276093
2010 Drosophila Mis12 complex acts as a single functional unit essential for anaphase chromosome movement and a robust spindle assembly checkpoint. Genetics 24 20980244
2019 Antigen-driven selection of antibodies against SSA, SSB and the centromere 'complex', including a novel antigen, MIS12 complex, in human salivary glands. Annals of the rheumatic diseases 20 31611218
2020 Mis12 controls cyclin B1 stabilization via Cdc14B-mediated APC/CCdh1 regulation during meiotic G2/M transition in mouse oocytes. Development (Cambridge, England) 15 32341029
2018 CENP-C/H/I/K/M/T/W/N/L and hMis12 but not CENP-S/X participate in complex formation in the nucleoplasm of living human interphase cells outside centromeres. PloS one 11 29509805
2024 FTO Stabilizes MIS12 to Inhibit Vascular Smooth Muscle Cell Senescence in Atherosclerotic Plaque. Journal of inflammation research 6 38523689
2020 C-Terminal Motifs of the MTW1 Complex Cooperatively Stabilize Outer Kinetochore Assembly in Budding Yeast. Cell reports 6 32997987
2016 MIS12/MIND Control at the Kinetochore. Cell 5 27814517
2009 Characterization of the two centromeric proteins CENP-C and MIS12 in Nicotiana species. Chromosome research : an international journal on the molecular, supramolecular and evolutionary aspects of chromosome biology 5 19697146
2024 CENP-C-Mis12 complex establishes a regulatory loop through Aurora B for chromosome segregation. Life science alliance 3 39433344
2019 Yeast screening system reveals the inhibitory mechanism of cancer cell proliferation by benzyl isothiocyanate through down-regulation of Mis12. Scientific reports 2 31222108
2024 Molecular details and phosphoregulation of the CENP-T-Mis12 complex interaction during mitosis in DT40 cells. iScience 1 39628583
2026 Screening, validation, and transcriptional regulation analysis of oxidative stress-related biomarkers in gestational diabetes mellitus: SH3BP5, ITGAM, PRRG1, and MIS12. European journal of medical research 0 41787525
2025 Dynamic phosphorylation of MIS12 ensures accurate kinetochore-microtubule attachment by expanding the fibrous corona. Molecular biology of the cell 0 40560426