{"gene":"SIX3","run_date":"2026-06-10T07:46:32","timeline":{"discoveries":[{"year":1995,"finding":"Six3 is a homeobox transcription factor expressed in the anterior neural plate, optic vesicles, lens, olfactory placodes, and ventral forebrain; its expression in Pax6 (Small eye) mutant mice is not affected, establishing it as acting independently of Pax6 at early stages.","method":"In situ hybridization, chromosomal mapping, expression analysis in Pax6 mutant mice","journal":"Development","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — direct expression analysis in mutant mice with negative epistasis result; single lab but multiple embryonic stages examined","pmids":["8575305"],"is_preprint":false},{"year":1996,"finding":"Ectopic expression of mouse Six3 in medaka fish embryos promotes ectopic lens formation in the area of the otic vesicle, demonstrating Six3 is sufficient to initiate lens formation independently of retinal tissue.","method":"Ectopic mRNA injection in medaka fish embryos, histological analysis","journal":"Mechanisms of development","confidence":"High","confidence_rationale":"Tier 2 / Strong — gain-of-function in vivo with clear phenotypic readout; replicated in subsequent studies","pmids":["9025075"],"is_preprint":false},{"year":1998,"finding":"Overexpression of Six3 in zebrafish embryos causes rostral forebrain enlargement and enhanced pax2 expression; disruption of either the Six domain or the homeodomain abolishes these effects, establishing both domains as essential for Six3 function.","method":"mRNA injection in zebrafish embryos, domain deletion mutant analysis","journal":"Development","confidence":"High","confidence_rationale":"Tier 1 / Moderate — domain mutagenesis combined with in vivo gain-of-function assay; single lab with multiple mutant constructs","pmids":["9655819"],"is_preprint":false},{"year":1999,"finding":"Overexpression of Six3 RNA in medaka fish initiates ectopic Pax6 and Rx2 expression, resulting in formation of ectopic retinal primordia; injected mouse Six3 also induces ectopic expression of endogenous medaka Six3, uncovering a feedback autoregulatory loop.","method":"mRNA injection in medaka embryos, in situ hybridization","journal":"Genes & development","confidence":"High","confidence_rationale":"Tier 2 / Strong — in vivo gain-of-function with molecular readout of target gene activation; replicated across labs","pmids":["10090721"],"is_preprint":false},{"year":1999,"finding":"Four different missense mutations in the homeodomain of human SIX3 are associated with holoprosencephaly and are predicted to interfere with transcriptional activation, establishing SIX3 as the HPE2 gene.","method":"Mutational analysis of HPE patients, chromosomal mapping, functional prediction","journal":"Nature genetics","confidence":"Medium","confidence_rationale":"Tier 3 / Strong — mutational analysis across multiple families; functional characterization limited in this paper but replicated by many subsequent studies","pmids":["10369266"],"is_preprint":false},{"year":2001,"finding":"Six3 interacts with the Groucho corepressor family member Grg3 via eh1-like motifs in the Six domain; point mutations in the eh1-like motifs reduce both forebrain-enlarging activity and Grg3 interaction, demonstrating Six3 functions as a Groucho-dependent transcriptional repressor in eye and forebrain formation.","method":"Yeast two-hybrid, mRNA injection in zebrafish, dominant activator/repressor constructs, eh1 motif mutagenesis","journal":"Developmental biology","confidence":"High","confidence_rationale":"Tier 1 / Moderate — yeast two-hybrid combined with in vivo mutagenesis functional assay; interaction confirmed with multiple orthogonal approaches","pmids":["11401394"],"is_preprint":false},{"year":2001,"finding":"Six3 acts as a transcriptional repressor at the gamma-crystallin (CRYGF) promoter, repressing it to ~10% of basal activity; functional assays define a Six3-responsive element between -101 and -123, and Six3 and Prox1 act antagonistically on CRYG promoters.","method":"Cell transfection reporter assay, randomly mutated promoter fragment analysis","journal":"Nucleic acids research","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — reporter gene assays with deletion mapping; single lab, multiple constructs","pmids":["11139622"],"is_preprint":false},{"year":2001,"finding":"Six3 promotes formation of ectopic optic vesicle-like structures in the hindbrain-midbrain region of developing mouse embryos upon ectopic expression; Six3 expression in the murine lens placodal ectoderm is controlled by Pax6.","method":"Ectopic Six3 expression in mouse embryos, analysis of Pax6 mutants","journal":"Developmental dynamics","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — in vivo gain-of-function with phenotypic readout plus epistasis with Pax6; single lab","pmids":["11458394"],"is_preprint":false},{"year":2001,"finding":"NOR-1 (NR4A3) orphan nuclear receptor interacts with Six3 in vitro and in yeast; the interaction requires the DNA binding and AF2 domains of NOR-1; Six3 negatively regulates NOR-1 transcriptional activity through the NBRE response element in a dose-dependent manner.","method":"Yeast two-hybrid, GST pulldown, cotransfection reporter assay","journal":"Developmental neuroscience","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — GST pulldown and cotransfection in single lab; multiple methods but no reciprocal Co-IP or structural confirmation","pmids":["11173923"],"is_preprint":false},{"year":2002,"finding":"Grg4 and Grg5, mouse Groucho homologs, physically interact with Six3 (and Six6); interaction requires the Q domain of Grg5 and a conserved phenylalanine in an eh1-like motif in the Six domain of Six3; Six3 acts as a potent transcriptional repressor via this interaction, and this interaction is required for Six3 auto-repression; disruption of the Groucho-interaction domain prevents lens placode invagination in chick and alters photoreceptor phenotype in rat retina.","method":"Co-immunoprecipitation, yeast two-hybrid, PCR DNA-binding motif identification, retroviral infection of rat retinae, chick in ovo electroporation with wild-type vs. eh1-mutant Six3","journal":"Development","confidence":"High","confidence_rationale":"Tier 2 / Strong — reciprocal Co-IP plus in vivo mutagenesis rescue experiments in two model systems; multiple orthogonal methods in one study","pmids":["12050133"],"is_preprint":false},{"year":2002,"finding":"Both Six3 and Six6 directly interact with TLE1 (Groucho family) and AES via the Six domain QD domain interface; Six3 additionally interacts with TLE proteins via the WDR domain; gain-of-function in medaka shows synergistic activity between SIX3/SIX6 and TLE1, while AES abrogates SIX3/6 overexpression phenotypes.","method":"Yeast two-hybrid with Six3/Six6 as baits, biochemical and mutational analysis, gain-of-function in medaka","journal":"Development","confidence":"High","confidence_rationale":"Tier 2 / Strong — yeast two-hybrid plus in vivo functional assays; replicated finding from two independent labs (also PMID 12050133)","pmids":["12441302"],"is_preprint":false},{"year":2002,"finding":"Pax6 and Six3 mutually activate each other's expression in the developing mouse lens; both transcription factors bind regulatory sequences of the counterpart gene in vitro and in transgenic approaches; Six3 expression in lenses of Pax6 heterozygous mice is specifically reduced, and lens-specific Six3 expression rescues the Pax6 haploinsufficient lens phenotype by activating platelet-derived growth factor alpha-R/cyclin D1 signaling.","method":"In vitro DNA-binding assays, transgenic mouse rescue experiments, cyclin D1 pathway analysis","journal":"PNAS","confidence":"High","confidence_rationale":"Tier 2 / Strong — in vitro binding plus transgenic rescue; multiple orthogonal methods establishing direct mutual regulatory relationship","pmids":["12072567"],"is_preprint":false},{"year":2003,"finding":"Six3 is a direct negative regulator of Wnt1 expression in the anterior neuroectoderm; in Six3-/- mice Wnt1 expression is rostrally expanded; ectopic Six3 expression in chick and zebrafish represses Wnt1; in vivo and in vitro DNA-binding assays confirm direct Six3 binding to Wnt1 regulatory sequences; Six3 rescues the headless/tcf3 zebrafish mutant phenotype through Wnt repression.","method":"Six3 knockout mice, ectopic Six3 expression in chick/zebrafish, in vivo and in vitro DNA-binding assays, phenotypic rescue of headless/tcf3 mutants","journal":"Genes & development","confidence":"High","confidence_rationale":"Tier 1 / Strong — loss-of-function mouse + gain-of-function in two model organisms + direct DNA-binding assay + genetic epistasis rescue; multiple labs implicitly through zebrafish and chick systems","pmids":["12569128"],"is_preprint":false},{"year":2003,"finding":"Six3 acts as a cofactor for the NOR-1 (NR4A3) orphan nuclear receptor; Six3 binds the DNA-binding domain of NOR-1 and the EWS domain of EWS/NOR-1 via its homeodomain in vitro; Six3 stimulates NOR-1 transcriptional activity but represses EWS/NOR-1 activity in cotransfection assays.","method":"GST fusion protein assays, mammalian two-hybrid, cotransfection reporter assays in immortalized chondrocytes","journal":"Cancer research","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — GST pulldown + mammalian two-hybrid + reporter assay; single lab, multiple methods","pmids":["12543801"],"is_preprint":false},{"year":2004,"finding":"Six3 physically competes with Cdt1 to bind geminin (the DNA replication inhibitor); Six3 efficiently displaces Cdt1 from geminin, revealing a non-transcriptional mechanism by which Six3 promotes cell proliferation in retinal precursors; overexpression of geminin in medaka induces forebrain/eye defects rescued by Six3; loss of geminin potentiates Six3 gain-of-function phenotypes.","method":"Yeast two-hybrid, direct protein competition binding assays, medaka overexpression/loss-of-function genetics","journal":"Nature","confidence":"High","confidence_rationale":"Tier 1 / Strong — direct in vitro competition binding assay plus in vivo genetic rescue/phenotype in medaka; multiple orthogonal methods in one high-impact study","pmids":["14973488"],"is_preprint":false},{"year":2004,"finding":"Three HPE-associated SIX3 homeodomain mutations have distinct functional consequences: L226V does not alter interaction with NOR-1; V250A produces a highly unstable protein; R257P abolishes in vivo interaction with NOR-1, suggesting different mutations affect different signaling pathways.","method":"GST pulldown assays, transient cotransfection in Neuro-2a cells, reporter assays","journal":"Human mutation","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — GST pulldown + reporter assay in cell lines; single lab, functional consequences of specific mutations defined","pmids":["15523651"],"is_preprint":false},{"year":2005,"finding":"Six3 promotes anterior neural plate expansion in Xenopus and zebrafish through transcriptional regulation of cell cycle regulators cyclinD1 and p27Xic1, as well as anti-neurogenic genes Zic2 and Xhairy2; Six3 also represses Bmp4 expression in adjacent ectoderm, and can expand the anterior neural plate even in the presence of cell cycle inhibitors, acting via BMP antagonism; Six3 cannot induce neural tissue alone but can do so in combination with Otx2.","method":"Ectopic Six3 expression in Xenopus and zebrafish, cell cycle inhibitor treatment, RT-PCR/in situ hybridization, chordino mutant rescue","journal":"Development","confidence":"High","confidence_rationale":"Tier 2 / Strong — gain-of-function in two model organisms with multiple molecular readouts and pharmacological dissection; multiple orthogonal approaches","pmids":["15843413"],"is_preprint":false},{"year":2005,"finding":"Six3 mediates cell proliferation in the developing forebrain by sequestering Geminin from Cdt1; Lhx2 can rescue forebrain size reduction caused by six3 morpholino knockdown in zebrafish, but Six3b cannot rescue Lhx2 knockdown, placing Lhx2 downstream of Six3 in a parallel/alternative pathway for forebrain proliferation.","method":"Antisense morpholino knockdown in zebrafish, caged-mRNA photoactivation, head-specific overexpression, genetic epistasis","journal":"Developmental biology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — morpholino + rescue experiments with photoactivatable mRNA; genetic epistasis established; single lab","pmids":["16226737"],"is_preprint":false},{"year":2005,"finding":"In developing mice, Six3 expression in the pre-placode lens ectoderm is initially Pax6-independent but subsequently becomes Pax6-dependent for both expression and nuclear localization; an in vitro protein-protein interaction is detected between Six3 and Eya1.","method":"Immunohistochemistry in Pax6 mutant mice, in vitro protein interaction assay","journal":"Gene expression patterns","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — in vitro pulldown for Six3-Eya1 interaction; Pax6-dependence of nuclear localization from IHC in mutant mice; single lab","pmids":["16024294"],"is_preprint":false},{"year":2006,"finding":"Six3 directly activates Pax6 and Sox2 expression in the presumptive lens ectoderm (PLE); conditional deletion of Six3 in the PLE disrupts lens induction and specification, downregulates Pax6, and eliminates Sox2; ChIP, EMSA, and luciferase reporter assays confirm direct Six3 binding to Pax6 and Sox2 regulatory sequences; misexpression of Six3 in chick promotes ectopic ectodermal Pax6 expression.","method":"Conditional knockout mice, ChIP, EMSA, luciferase reporter assays, misexpression in chick embryos","journal":"EMBO journal","confidence":"High","confidence_rationale":"Tier 1 / Strong — ChIP + EMSA + reporter assay + conditional KO + in vivo misexpression; multiple orthogonal methods in single rigorous study","pmids":["17066077"],"is_preprint":false},{"year":2007,"finding":"Six3 inactivation causes progressive caudalization of the diencephalon; at 15-17 somites, Wnt1 expression is anteriorly expanded in Six3-null brains; Six3;Wnt1 double-null mice reveal that Six3-mediated repression of Wnt1 is necessary for formation of the rostral diencephalon, and that Six3 activity is required for telencephalon formation.","method":"Six3 knockout, Six3;Wnt1 double knockout mice, in situ hybridization","journal":"Development","confidence":"High","confidence_rationale":"Tier 2 / Strong — double mutant genetic epistasis with defined molecular phenotype; replicated across two knockout models in single lab","pmids":["18094027"],"is_preprint":false},{"year":2007,"finding":"MTA1 physically interacts with Six3 chromatin in a histone deacetylase (HDAC)-dependent manner, leading to transcriptional suppression of Six3; MTA1 is also a Six3-interacting corepressor contributing to self-negative regulation of Six3 transcription; loss of MTA1 in null mice leads to elevated Six3 and enhanced recruitment of Six3 to the rhodopsin promoter; Six3 homeodomain binds specific DNA elements in the rhodopsin promoter to stimulate rhodopsin transcription; Six3 cooperates with Crx or NRL to stimulate rhodopsin-luc transcription; HPE-associated Six3 deletion mutations in helix 3 of the homeodomain abolish rhodopsin promoter binding.","method":"ChIP, co-immunoprecipitation, MTA1-null mice, knockdown in rat retinal ganglion cells, luciferase reporter assays with HPE mutations","journal":"PNAS","confidence":"High","confidence_rationale":"Tier 2 / Strong — ChIP + Co-IP + null mouse model + knockdown + reporter assay + HPE mutation functional testing; multiple orthogonal methods in one study","pmids":["17666527"],"is_preprint":false},{"year":2007,"finding":"Six3 regulates diencephalic Nodal signaling activity; reduction of Six3 function causes brain-specific deregulation of Nodal pathway activity resulting in epithalamic laterality defects; misexpression and genetic epistasis in zebrafish indicate Six3 acts in the neuroectoderm to establish bilateral repression of Nodal activity, which is subsequently alleviated ipsilaterally by left-side Nodal signaling from lateral plate mesoderm.","method":"Zebrafish morpholino knockdown, Six3 misexpression, genetic epistasis experiments","journal":"Neuron","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — morpholino knockdown + misexpression + genetic epistasis; single lab, multiple methods","pmids":["17678854"],"is_preprint":false},{"year":2008,"finding":"Six3 directly binds and activates the Shh brain enhancer-2 (SBE2) located 460 kb upstream of SHH in the hypothalamus; HPE-causing Six3 alterations fail to bind and activate SBE2; DNA affinity-capture assay identified Six3 and Six6 as candidate regulators of Shh transcription; the mutant SBE2 sequence from an HPE patient shows reduced Six3 binding affinity.","method":"DNA affinity-capture assay, transgenic mouse enhancer assay, Six3 HPE mutation binding analysis","journal":"Nature genetics","confidence":"High","confidence_rationale":"Tier 1 / Moderate — direct DNA-binding assay + transgenic enhancer assay + HPE mutation functional testing; multiple orthogonal methods in single study","pmids":["18836447"],"is_preprint":false},{"year":2008,"finding":"Haploinsufficiency of Six3 (by deletion of one allele or replacement with HPE-associated alleles) causes HPE in mice; Shh is a direct target of Six3 in the rostral diencephalon ventral midline (RDVM); reduced Six3 fails to activate Shh expression in the mutant RDVM, leading to HPE; a crossregulatory loop between Shh and Six3 exists in the ventral forebrain.","method":"Six3 heterozygous and knockin mouse models, ChIP for direct Six3-Shh target validation, zebrafish functional assays for HPE mutations","journal":"Developmental cell","confidence":"High","confidence_rationale":"Tier 1 / Strong — ChIP confirming direct target + loss-of-function mouse models + zebrafish hypomorph assays + HPE allele knockin; multiple orthogonal methods, replicated across species","pmids":["18694563"],"is_preprint":false},{"year":2008,"finding":"89% of HPE-associated SIX3 mutations function as loss-of-function alleles in zebrafish assays; disease-associated single point mutations in the Groucho-binding eh1-like motif decrease function in all assays, confirming that Groucho co-repressor interaction is essential for human SIX3 function and HPE causation; truncated SIX3 proteins missing the homeodomain retain partial function.","method":"Zebrafish functional assays for 46 distinct SIX3 mutations, eh1 motif mutational analysis","journal":"Human molecular genetics","confidence":"High","confidence_rationale":"Tier 2 / Strong — systematic functional characterization of 46 mutations in zebrafish assays; large-scale mutational analysis with clear mechanistic conclusions","pmids":["18791198"],"is_preprint":false},{"year":2009,"finding":"EYA4 is co-immunoprecipitated with SIX3 from cells; SIX3 recruits EYA4 (normally cytoplasmic) to the nucleus; EYA4 cooperates with SIX3 as a transcriptional coactivator in reporter gene assays, establishing a physical and functional SIX3-EYA4 interaction.","method":"Co-immunoprecipitation, confocal microscopy for nuclear recruitment, reporter gene assays","journal":"Human mutation","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — Co-IP + confocal localization + reporter assay; single lab, three orthogonal methods","pmids":["19606496"],"is_preprint":false},{"year":2010,"finding":"Six3 directly represses Wnt8b expression in the developing neuroretina; conditional deletion of Six3 causes ectopic rostral expansion of Wnt8b and failure of neuroretina specification; ectopic Wnt8b transgenic expression is sufficient to suppress neuroretina specification; ChIP identified Six3-responsive elements in the Wnt8b locus.","method":"Conditional Six3 knockout mice, ChIP, Wnt8b transgenic overexpression","journal":"Journal of clinical investigation","confidence":"High","confidence_rationale":"Tier 1 / Strong — conditional KO + ChIP direct target validation + transgenic epistasis; multiple orthogonal methods in single rigorous study","pmids":["20890044"],"is_preprint":false},{"year":2010,"finding":"MTA1s and MTA1 physically interact with Six3 chromatin and inhibit Six3 transcription in an HDAC-dependent manner, relieving Six3-mediated repression of Wnt1 promoter; deletion of MTA1s/MTA1 in MEFs results in upregulation of Six3 and downregulation of Wnt signaling; in MTA1s/MTA1-null mammary glands, increased Six3 corepressor complex is recruited to the Wnt1 promoter.","method":"Co-immunoprecipitation, ChIP in null MEFs and mammary glands, gain/loss-of-function experiments","journal":"Cancer research","confidence":"High","confidence_rationale":"Tier 2 / Strong — ChIP + Co-IP + null mouse model + gain/loss-of-function; multiple orthogonal methods across cell and mouse models","pmids":["20682799"],"is_preprint":false},{"year":2010,"finding":"The Six3 homeodomain binds to a TAATGTC motif (a newly defined recognition sequence distinct from the common TGATAC Six family motif) at multiple sites within the six3a promoter with high affinity; ChIP confirms Six3a binding to promoter fragments containing clustered TAATGTC sites in vivo; these sites mediate autoregulation in zebrafish embryos.","method":"In vitro DNA-binding affinity assays, single-nucleotide substitution analysis, ChIP, transient reporter assays in zebrafish embryos","journal":"FEBS journal","confidence":"High","confidence_rationale":"Tier 1 / Moderate — in vitro binding assay with mutagenesis + ChIP in vivo + reporter assay in embryos; multiple orthogonal methods in single study","pmids":["20193042"],"is_preprint":false},{"year":2011,"finding":"Six3 is required for ependymal cell maturation during postnatal brain development; in Six3's absence, ependymal cells fail to suppress radial glia characteristics, resulting in a defective lateral wall, abnormal neuroblast migration and differentiation, and hydrocephaly.","method":"Six3 conditional knockout in ependymal cells, histological and molecular marker analysis","journal":"Development","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — conditional knockout with specific cellular and molecular phenotypic readouts; single lab","pmids":["22071110"],"is_preprint":false},{"year":2012,"finding":"In zebrafish, Six3 (six3b and six7) cooperates with Hedgehog signaling to specify ventral telencephalon; Six3 promotes ventral telencephalic fates through transient regulation of foxg1a expression and repression of Wnt/β-catenin signaling; Six3 overexpression can compensate for loss of Hh signaling in isl1- but not nkx2.1b-positive cells, indicating a Hh-independent role for Six3.","method":"Zebrafish morpholino knockdown of six3b and six7, overexpression, Hh pathway inhibition/activation assays","journal":"Development","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — morpholino knockdown + overexpression + pathway epistasis; single lab, multiple functional assays","pmids":["22736245"],"is_preprint":false},{"year":2013,"finding":"Sox2 directly regulates a long-range forebrain enhancer to activate Six3 expression in the rostral diencephalon; biochemical and genetic evidence establish a direct regulatory link between Sox2 and Six3 during forebrain development.","method":"Genomic ChIP-seq for Sox2 binding, in vivo transgenic enhancer assay, genetic epistasis","journal":"Developmental biology","confidence":"High","confidence_rationale":"Tier 1 / Moderate — ChIP-seq + transgenic enhancer assay + genetic evidence; multiple orthogonal methods in single study","pmids":["23792023"],"is_preprint":false},{"year":2016,"finding":"Six3 dosage determines HPE severity in mice: semilobar HPE results from severe downregulation of Shh expression in the rostral diencephalon ventral midline, while alobar HPE is caused by downregulation of Foxg1 expression in the anterior neural ectoderm; in vivo Shh pathway activation rescues semilobar but not alobar HPE.","method":"Novel hypomorphic Six3 allele mice, in vivo Shh pathway activation, gene expression analysis","journal":"Development","confidence":"High","confidence_rationale":"Tier 2 / Strong — hypomorphic allele dosage series + pathway-specific rescue; mechanistically dissects two distinct downstream pathways","pmids":["27770010"],"is_preprint":false},{"year":2017,"finding":"Six3 repression of R-spondin 2 (Rspo2) is required during optic vesicle morphogenesis and neuroretina differentiation; transient ectopic Rspo2 expression in the anterior neural plate of transgenic mouse embryos is sufficient to inhibit neuroretina differentiation; Six3-null cells exert a non-cell-autonomous repressive effect on optic vesicle formation.","method":"Six3-/- iPSC eye organoid, conditional null ESC organoid, in vivo transgenic Rspo2 overexpression, chimeric eye organoid assay","journal":"Cell reports","confidence":"High","confidence_rationale":"Tier 2 / Strong — iPSC/ESC organoid models + in vivo transgenic epistasis + chimeric assay; multiple orthogonal methods","pmids":["29117559"],"is_preprint":false},{"year":2017,"finding":"SIX3 directly binds to the promoter regions of AURKA and AURKB (aurora kinases A and B) to repress their transcription in a dose-dependent manner; SIX3 increases p53 activity at the post-translational level through negative regulation of AURKA or AURKB; SIX3 overexpression does not affect AURKA-AURKB protein stabilization interactions.","method":"ChIP, luciferase reporter assay, Co-IP for AURKA-AURKB interaction, flow cytometry, colony formation/intracranial xenograft assays","journal":"Journal of hematology & oncology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — ChIP + reporter assay confirming direct promoter binding; functional assays in astrocytoma cells; single lab","pmids":["28595628"],"is_preprint":false},{"year":2017,"finding":"Six3 in a small population of anteroventral optic vesicle progenitors at E8.5 is required for neuroretinal specification; Six3 deletion in these progenitors causes rostral expansion of Wnt8b and drastic reduction of Fgf8/MAPK signaling, ablating neuroretinal specification without affecting RPE; Six3-Cre positive progenies are found in neuroretina and optic stalk but not RPE.","method":"Lineage tracing with Six3-Cre in wild-type and Six3-deficient mice, gene expression analysis by ISH/immunostaining","journal":"Developmental biology","confidence":"High","confidence_rationale":"Tier 2 / Strong — lineage tracing + conditional KO + molecular pathway readouts; mechanistically precise mapping of Six3 function to specific progenitor population","pmids":["28579317"],"is_preprint":false},{"year":2018,"finding":"SIX3 forms a complex with LSD1/NuRD(MTA3) identified by affinity purification and mass spectrometry; this complex represses WNT1 and FOXC2 (involved in EMT) as identified by ChIP-on-chip genome-wide analysis; the SIX3/LSD1/NuRD(MTA3) complex inhibits carcinogenesis and metastasis in breast cancer cells.","method":"Affinity purification + mass spectrometry, ChIP-on-chip, in vitro and in vivo functional assays","journal":"Theranostics","confidence":"High","confidence_rationale":"Tier 1 / Moderate — AP-MS complex identification + genome-wide ChIP-on-chip; multiple orthogonal methods in single study","pmids":["29463994"],"is_preprint":false},{"year":2018,"finding":"SP8 and SP9 directly activate Six3 expression in a spatially restricted LGE subventricular zone domain; ChIP-seq shows SP9 directly binds the promoter and a putative enhancer of Six3; conditional deletion of Six3 prevents formation of most D2 MSNs, phenocopying Sp8/9 double mutants.","method":"Conditional knockout mice (Sp8/Sp9 and Six3), ChIP-seq, in situ hybridization, immunostaining","journal":"Development","confidence":"High","confidence_rationale":"Tier 1 / Strong — ChIP-seq for direct binding + conditional knockout phenocopy; multiple methods in single study","pmids":["29967281"],"is_preprint":false},{"year":2018,"finding":"Six3 and Six6 are jointly required for maintenance of multipotent neuroretinal progenitors; double knockout retinas show ectopic upregulation of Wnt3a, Fzd1, Otx1 and Cdon (ciliary margin markers) and loss of neuroretinal progenitor markers Sox2, Notch1, Otx2; stimulation of Wnt/β-catenin signaling promotes ciliary margin progenitors at the cost of neuroretinal identity, indicating Six3 and Six6 together directly or indirectly suppress Wnt/β-catenin signaling.","method":"Six3/Six6 double conditional knockout mice, Wnt-3a and GSK3β inhibitor treatment of eye cups, gene expression analysis","journal":"Cell reports","confidence":"High","confidence_rationale":"Tier 2 / Strong — double conditional knockout + pharmacological Wnt pathway manipulation + molecular markers; multiple orthogonal approaches","pmids":["30485816"],"is_preprint":false},{"year":2020,"finding":"EGFR activation induces DNA methylation silencing of SIX3 through the MAPK pathway: activated ERK binds ZNF263, abrogates its ubiquitination and stabilizes it; ZNF263 binds the core SIX3 promoter and recruits the KAP1/HATS/DNMT corepressor complex inducing H3K27me3 and DNA methylation at the SIX3 promoter.","method":"Co-immunoprecipitation, ChIP, ubiquitination assay, MAPK pathway inhibition/activation, reporter assays","journal":"Oncogene","confidence":"High","confidence_rationale":"Tier 2 / Strong — Co-IP + ChIP + ubiquitination assay + pathway epistasis; multiple orthogonal methods defining the upstream silencing mechanism","pmids":["32051553"],"is_preprint":false},{"year":2020,"finding":"TRIM27 E3 ubiquitin ligase ubiquitinates and degrades SIX3 protein, activating Wnt/β-catenin signaling; SIX3 negatively regulates β-catenin, S100P, TGFB3, and MMP-9 expression in NSCLC cells.","method":"Ubiquitination assay, co-immunoprecipitation, loss/gain-of-function in NSCLC cells, XAV939 pathway inhibition","journal":"Aging","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — ubiquitination assay + Co-IP + functional rescue; single lab, multiple methods","pmids":["33264103"],"is_preprint":false},{"year":2021,"finding":"SIX3 suppression in human adult pancreatic islets by shRNA impairs insulin secretion; SIX3 loss leads to inappropriate expression of genes normally expressed in fetal β cells, adult α cells, and non-β cells, indicating SIX3 maintains developmental fate and suppresses non-β-cell gene programs; SIX2 and SIX3 regulate distinct target gene sets.","method":"shRNA knockdown in human adult islets, transcriptome analysis, chromatin accessibility studies","journal":"Genes & development","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — functional knockdown in primary human tissue with transcriptomic readout; chromatin accessibility data; single lab","pmids":["33446570"],"is_preprint":false},{"year":2021,"finding":"Six3 functions in D2 MSN precursor cells to drive their differentiation; conditional deletion of Six3 blocks differentiation without affecting proliferation, and conditionally overexpressed Six3 promotes LGE precursor differentiation; abnormally differentiated D2 MSNs in Six3-KO are eliminated by apoptosis postnatally.","method":"Conditional Six3 knockout and overexpression in mice, BrdU/EdU proliferation assays, TUNEL apoptosis assay, immunostaining","journal":"Neuroscience bulletin","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — conditional KO + conditional OE + multiple cellular readouts; single lab","pmids":["34014554"],"is_preprint":false}],"current_model":"SIX3 is a homeodomain transcription factor that functions primarily as a transcriptional repressor (via direct interaction with Groucho/TLE family corepressors through an eh1-like motif in its Six domain) but also as a context-dependent activator; it directly represses Wnt1, Wnt8b, R-spondin 2, AURKA/B, and other targets while directly activating Shh (via SBE2 enhancer binding) and Pax6/Sox2 in the lens ectoderm, positioning Six3 at the top of regulatory cascades governing anterior neural plate specification, forebrain development, eye and neuroretina morphogenesis, and HPE pathogenesis; additionally, Six3 promotes cell proliferation through a non-transcriptional mechanism by competing with Cdt1 for geminin binding, and its activity is modulated by upstream regulators including MTA1 (HDAC-dependent chromatin silencing), TRIM27 (ubiquitin-mediated degradation), ZNF263/EGFR (epigenetic silencing via H3K27me3 and DNA methylation), and Sox2 (transcriptional activation via a long-range enhancer)."},"narrative":{"mechanistic_narrative":"SIX3 is a homeodomain transcription factor that sits at the top of the gene-regulatory hierarchy specifying the anterior neural plate, forebrain, and eye, with both its Six domain and homeodomain required for activity [PMID:8575305, PMID:9655819, PMID:17066077]. It acts predominantly as a Groucho/TLE-dependent transcriptional repressor, binding corepressors (Grg3/Grg4/Grg5, TLE1, AES) through an eh1-like motif in its Six domain; mutation of this motif simultaneously abolishes corepressor binding and developmental activity [PMID:11401394, PMID:12050133, PMID:12441302]. Through this repressive activity SIX3 directly silences Wnt pathway components—Wnt1, Wnt8b, and R-spondin 2—to restrict caudalizing Wnt/β-catenin signaling and permit rostral diencephalon, telencephalon, and neuroretina specification [PMID:12569128, PMID:18094027, PMID:20890044, PMID:29117559]. In a context-dependent activating mode, SIX3 binds and activates the long-range SHH brain enhancer SBE2 in the rostral diencephalon and directly activates Pax6 and Sox2 in the presumptive lens ectoderm to drive lens and eye induction [PMID:17066077, PMID:18836447, PMID:18694563]. SIX3 also drives progenitor proliferation through a non-transcriptional mechanism, competing with Cdt1 for binding to the replication inhibitor geminin in retinal and forebrain precursors [PMID:14973488, PMID:16226737]. Its own expression is autoregulated via direct binding to a TAATGTC motif in its promoter and is set by upstream inputs including Sox2 and SP8/SP9 enhancer activation and MTA1/NuRD-dependent corepression [PMID:17666527, PMID:20193042, PMID:23792023, PMID:29967281]. Heterozygous loss-of-function mutations in human SIX3—including homeodomain and eh1-motif point mutations that disrupt DNA binding and corepressor interaction—cause holoprosencephaly (HPE2), with dosage determining severity through differential loss of Shh versus Foxg1 expression [PMID:10369266, PMID:18694563, PMID:18791198, PMID:27770010].","teleology":[{"year":1995,"claim":"Established SIX3 as an early anterior neural/eye-field homeobox factor acting upstream of and independently from Pax6, defining its position in the developmental hierarchy.","evidence":"In situ hybridization and expression analysis in Pax6 mutant mice","pmids":["8575305"],"confidence":"Medium","gaps":["No direct target genes identified","Repressor versus activator function unresolved at this stage"]},{"year":1999,"claim":"Demonstrated SIX3 is sufficient to induce eye-field programs by triggering ectopic lens and retinal primordia and revealed an autoregulatory feedback loop.","evidence":"Ectopic mRNA injection in medaka and zebrafish with target-gene in situ readouts","pmids":["9025075","9655819","10090721"],"confidence":"High","gaps":["Direct versus indirect target activation not distinguished","Domain requirements for autoregulation not yet mapped"]},{"year":1999,"claim":"Linked SIX3 to human disease, identifying homeodomain mutations as the cause of holoprosencephaly (HPE2).","evidence":"Mutational analysis of HPE patient families with functional prediction","pmids":["10369266"],"confidence":"Medium","gaps":["Functional consequences of mutations predicted, not measured","Downstream pathway affected unknown"]},{"year":2001,"claim":"Defined the molecular basis of SIX3 repression by showing it recruits Groucho/Grg corepressors through an eh1-like motif required for forebrain activity and autorepression.","evidence":"Yeast two-hybrid, Co-IP, eh1 motif mutagenesis with in vivo assays in zebrafish, chick, and rat retina","pmids":["11401394","12050133","12441302","11139622"],"confidence":"High","gaps":["Direct genomic repression targets not yet identified","Switch between repressor and activator modes unexplained"]},{"year":2002,"claim":"Connected SIX3 to lens induction through a mutual cross-activation loop with Pax6 driving downstream proliferative signaling.","evidence":"In vitro DNA binding and transgenic mouse rescue of Pax6 haploinsufficiency","pmids":["12072567"],"confidence":"High","gaps":["Direct binding sites in the Pax6 locus not finely mapped here","Temporal order of mutual activation incompletely resolved"]},{"year":2003,"claim":"Identified Wnt1 as a direct repression target, establishing SIX3's role in restricting caudalizing Wnt signaling to pattern the anterior brain.","evidence":"Six3 knockout mice, gain-of-function in chick/zebrafish, DNA-binding assays, and headless/tcf3 rescue","pmids":["12569128"],"confidence":"High","gaps":["Full set of Wnt-pathway targets unknown","Corepressor requirement at the Wnt1 locus not yet shown"]},{"year":2004,"claim":"Revealed a non-transcriptional proliferative mechanism whereby SIX3 sequesters geminin from Cdt1 to license replication in neural/retinal precursors.","evidence":"Direct protein competition binding assays plus medaka overexpression/loss-of-function genetics","pmids":["14973488","16226737"],"confidence":"High","gaps":["Quantitative contribution of this mechanism versus transcriptional outputs unclear","Regulation of the SIX3-geminin interaction unknown"]},{"year":2006,"claim":"Showed SIX3 directly activates Pax6 and Sox2 in the lens ectoderm, demonstrating a bona fide context-dependent activator function distinct from its repressive role.","evidence":"Conditional knockout, ChIP, EMSA, luciferase reporters, and chick misexpression","pmids":["17066077"],"confidence":"High","gaps":["Coactivator partners at activated loci not defined","Determinants of activator versus repressor outcome unresolved"]},{"year":2008,"claim":"Established SIX3 as a direct activator of SHH via the long-range SBE2 enhancer and mechanistically tied HPE mutations to failed Shh activation.","evidence":"DNA affinity-capture, transgenic enhancer assays, ChIP, and HPE allele knockin/mutation testing","pmids":["18836447","18694563","18791198"],"confidence":"High","gaps":["Coactivators enabling SHH activation not identified","How a repressor-prone factor activates SBE2 not mechanistically resolved"]},{"year":2010,"claim":"Extended the Wnt-repression program to Wnt8b in the neuroretina, establishing SIX3-mediated Wnt suppression as essential for neuroretina specification.","evidence":"Conditional knockout, ChIP, and Wnt8b transgenic epistasis","pmids":["20890044","20682799"],"confidence":"High","gaps":["Whether one corepressor complex serves all Wnt targets unknown","Cell-type specificity of target choice unexplained"]},{"year":2010,"claim":"Defined SIX3 autoregulation at the DNA level by identifying a non-canonical TAATGTC recognition motif clustered in its own promoter.","evidence":"In vitro binding with single-nucleotide substitution, ChIP, and zebrafish reporter assays","pmids":["20193042","17666527"],"confidence":"High","gaps":["Genome-wide preference for TAATGTC versus canonical sites unmeasured","Structural basis of motif selectivity unknown"]},{"year":2016,"claim":"Resolved how SIX3 dosage dictates HPE severity by separating Shh-dependent (semilobar) from Foxg1-dependent (alobar) phenotypes.","evidence":"Hypomorphic allele dosage series with pathway-specific in vivo Shh rescue","pmids":["27770010","20193042"],"confidence":"High","gaps":["Whether Foxg1 is a direct SIX3 target not established","Threshold mechanism distinguishing the two pathways unknown"]},{"year":2017,"claim":"Mapped SIX3 function to a defined anteroventral optic vesicle progenitor population and added R-spondin 2 to its directly repressed Wnt-modulating targets.","evidence":"Lineage tracing, conditional KO, iPSC/ESC organoids, and Rspo2 transgenic epistasis","pmids":["28579317","29117559"],"confidence":"High","gaps":["Mechanism of non-cell-autonomous repression of optic vesicle formation unclear","Direct binding at the Rspo2 locus not detailed"]},{"year":2018,"claim":"Defined the upstream transcriptional and epigenetic control of SIX3, identifying Sox2 and SP8/SP9 as direct enhancer/promoter activators and the LSD1/NuRD(MTA3) complex as a SIX3 partner controlling Wnt1/EMT genes.","evidence":"ChIP-seq, transgenic enhancer assays, conditional knockouts, and AP-MS complex identification","pmids":["23792023","29967281","29463994"],"confidence":"High","gaps":["Composition of the SIX3 corepressor complex in neural contexts not fully defined","Whether NuRD recruitment generalizes to developmental targets unknown"]},{"year":2020,"claim":"Established post-transcriptional and epigenetic silencing of SIX3 as a tumor-relevant axis via EGFR/MAPK-ZNF263-driven promoter methylation and TRIM27-mediated protein degradation.","evidence":"Co-IP, ChIP, ubiquitination assays, and pathway epistasis in cancer cells","pmids":["32051553","33264103","28595628"],"confidence":"High","gaps":["Physiological relevance of these regulators in normal development untested","Direct SIX3 binding at AURKA/AURKB versus indirect effects partly unresolved"]},{"year":2021,"claim":"Revealed a postnatal cell-identity maintenance role, with SIX3 sustaining adult β-cell and D2 MSN differentiation programs and suppressing alternative fates.","evidence":"shRNA knockdown in human islets with transcriptomics, and conditional KO/overexpression in mouse striatum","pmids":["33446570","34014554"],"confidence":"Medium","gaps":["Direct target genes maintaining cell identity not defined","Whether identity maintenance uses the same corepressor machinery as development unknown"]},{"year":null,"claim":"The molecular determinant that switches SIX3 between Groucho-dependent repression and context-specific activation of SHH/Pax6/Sox2 remains unresolved.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No structural model explaining repressor/activator partner selection","Coactivators required for SBE2/Pax6 activation not identified","How upstream chromatin state biases target choice unknown"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0140110","term_label":"transcription regulator activity","supporting_discovery_ids":[5,9,12,19,23,35]},{"term_id":"GO:0003677","term_label":"DNA binding","supporting_discovery_ids":[12,19,23,27,29,35]},{"term_id":"GO:0140313","term_label":"molecular sequestering activity","supporting_discovery_ids":[14,17]},{"term_id":"GO:0098772","term_label":"molecular function regulator activity","supporting_discovery_ids":[8,13,26]}],"localization":[{"term_id":"GO:0005634","term_label":"nucleus","supporting_discovery_ids":[18,26]},{"term_id":"GO:0005654","term_label":"nucleoplasm","supporting_discovery_ids":[21,28,37]}],"pathway":[{"term_id":"R-HSA-1266738","term_label":"Developmental Biology","supporting_discovery_ids":[12,19,20,24,36]},{"term_id":"R-HSA-74160","term_label":"Gene expression (Transcription)","supporting_discovery_ids":[5,19,23,27,35]},{"term_id":"R-HSA-162582","term_label":"Signal Transduction","supporting_discovery_ids":[12,27,34,39,41]},{"term_id":"R-HSA-1643685","term_label":"Disease","supporting_discovery_ids":[4,24,33,35,40]},{"term_id":"R-HSA-1640170","term_label":"Cell Cycle","supporting_discovery_ids":[14,16,17]}],"complexes":["SIX3/LSD1/NuRD(MTA3)","SIX3-Groucho/TLE corepressor complex"],"partners":["TLE1","AES","GEMININ","PAX6","EYA4","MTA1","NR4A3","TRIM27"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"O95343","full_name":"Homeobox protein SIX3","aliases":["Sine oculis homeobox homolog 3"],"length_aa":332,"mass_kda":35.5,"function":"Transcriptional regulator which can act as both a transcriptional repressor and activator by binding a ATTA homeodomain core recognition sequence on these target genes. During forebrain development represses WNT1 expression allowing zona limitans intrathalamica formation and thereby ensuring proper anterio-posterior patterning of the diencephalon and formation of the rostral diencephalon. Acts as a direct upstream activator of SHH expression in the rostral diencephalon ventral midline and that in turn SHH maintains its expression. In addition, Six3 activity is required for the formation of the telencephalon. During postnatal stages of brain development is necessary for ependymal cell maturation by promoting the maturation of radial glia into ependymal cells through regulation of neuroblast proliferation and migration. Acts on the proliferation and differentiation of neural progenitor cells through activating transcription of CCND1 and CCND2. During early lens formation plays a role in lens induction and specification by activating directly PAX6 in the presumptive lens ectoderm. In turn PAX6 activates SIX3 resulting in activation of PDGFRA and CCND1 promoting cell proliferation. Also is required for the neuroretina development by directly suppressing WNT8B expression in the anterior neural plate territory. Its action during retina development and lens morphogenesis is TLE5 and TLE4-dependent manner. Furthermore, during eye development regulates several genes expression. Before and during early lens development represses the CRYGF promoter by binding a SIX repressor element. Directly activates RHO transcription, or cooperates with CRX or NRL. Six3 also functions in the formation of the proximodistal axis of the optic cup, and promotes the formation of optic vesicles-like structures. During pituitary development, acts in parallel or alternatively with HESX1 to control cell proliferation through Wnt/beta-catenin pathway (By similarity). Plays a role in eye development by suppressing WNT1 expression and in dorsal-ventral patterning by repressing BMP signaling pathway","subcellular_location":"Nucleus","url":"https://www.uniprot.org/uniprotkb/O95343/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/SIX3","classification":"Not Classified","n_dependent_lines":2,"n_total_lines":1208,"dependency_fraction":0.0016556291390728477},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[],"url":"https://opencell.sf.czbiohub.org/search/SIX3","total_profiled":1310},"omim":[{"mim_id":"621143","title":"HOLOPROSENCEPHALY 10; HPE10","url":"https://www.omim.org/entry/621143"},{"mim_id":"621003","title":"TRANSCRIPTION FACTOR Sp9; SP9","url":"https://www.omim.org/entry/621003"},{"mim_id":"615465","title":"HARTSFIELD SYNDROME; HRTFDS","url":"https://www.omim.org/entry/615465"},{"mim_id":"610829","title":"HOLOPROSENCEPHALY 9; HPE9","url":"https://www.omim.org/entry/610829"},{"mim_id":"609637","title":"HOLOPROSENCEPHALY 5; HPE5","url":"https://www.omim.org/entry/609637"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Approved","locations":[{"location":"Nucleoplasm","reliability":"Approved"}],"tissue_specificity":"Tissue enhanced","tissue_distribution":"Detected in some","driving_tissues":[{"tissue":"brain","ntpm":36.9},{"tissue":"pituitary gland","ntpm":25.1},{"tissue":"retina","ntpm":23.5}],"url":"https://www.proteinatlas.org/search/SIX3"},"hgnc":{"alias_symbol":[],"prev_symbol":["HPE2"]},"alphafold":{"accession":"O95343","domains":[{"cath_id":"1.25.40","chopping":"88-195","consensus_level":"high","plddt":88.8081,"start":88,"end":195},{"cath_id":"1.10.10.60","chopping":"214-274","consensus_level":"high","plddt":92.0108,"start":214,"end":274}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/O95343","model_url":"https://alphafold.ebi.ac.uk/files/AF-O95343-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-O95343-F1-predicted_aligned_error_v6.png","plddt_mean":67.88},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=SIX3","jax_strain_url":"https://www.jax.org/strain/search?query=SIX3"},"sequence":{"accession":"O95343","fasta_url":"https://rest.uniprot.org/uniprotkb/O95343.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/O95343/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/O95343"}},"corpus_meta":[{"pmid":"8575305","id":"PMC_8575305","title":"Six3, 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single lab but multiple embryonic stages examined\",\n      \"pmids\": [\"8575305\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1996,\n      \"finding\": \"Ectopic expression of mouse Six3 in medaka fish embryos promotes ectopic lens formation in the area of the otic vesicle, demonstrating Six3 is sufficient to initiate lens formation independently of retinal tissue.\",\n      \"method\": \"Ectopic mRNA injection in medaka fish embryos, histological analysis\",\n      \"journal\": \"Mechanisms of development\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — gain-of-function in vivo with clear phenotypic readout; replicated in subsequent studies\",\n      \"pmids\": [\"9025075\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1998,\n      \"finding\": \"Overexpression of Six3 in zebrafish embryos causes rostral forebrain enlargement and enhanced pax2 expression; disruption of either the Six domain or the homeodomain abolishes these effects, establishing both domains as essential for Six3 function.\",\n      \"method\": \"mRNA injection in zebrafish embryos, domain deletion mutant analysis\",\n      \"journal\": \"Development\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — domain mutagenesis combined with in vivo gain-of-function assay; single lab with multiple mutant constructs\",\n      \"pmids\": [\"9655819\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1999,\n      \"finding\": \"Overexpression of Six3 RNA in medaka fish initiates ectopic Pax6 and Rx2 expression, resulting in formation of ectopic retinal primordia; injected mouse Six3 also induces ectopic expression of endogenous medaka Six3, uncovering a feedback autoregulatory loop.\",\n      \"method\": \"mRNA injection in medaka embryos, in situ hybridization\",\n      \"journal\": \"Genes & development\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — in vivo gain-of-function with molecular readout of target gene activation; replicated across labs\",\n      \"pmids\": [\"10090721\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1999,\n      \"finding\": \"Four different missense mutations in the homeodomain of human SIX3 are associated with holoprosencephaly and are predicted to interfere with transcriptional activation, establishing SIX3 as the HPE2 gene.\",\n      \"method\": \"Mutational analysis of HPE patients, chromosomal mapping, functional prediction\",\n      \"journal\": \"Nature genetics\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Strong — mutational analysis across multiple families; functional characterization limited in this paper but replicated by many subsequent studies\",\n      \"pmids\": [\"10369266\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2001,\n      \"finding\": \"Six3 interacts with the Groucho corepressor family member Grg3 via eh1-like motifs in the Six domain; point mutations in the eh1-like motifs reduce both forebrain-enlarging activity and Grg3 interaction, demonstrating Six3 functions as a Groucho-dependent transcriptional repressor in eye and forebrain formation.\",\n      \"method\": \"Yeast two-hybrid, mRNA injection in zebrafish, dominant activator/repressor constructs, eh1 motif mutagenesis\",\n      \"journal\": \"Developmental biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — yeast two-hybrid combined with in vivo mutagenesis functional assay; interaction confirmed with multiple orthogonal approaches\",\n      \"pmids\": [\"11401394\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2001,\n      \"finding\": \"Six3 acts as a transcriptional repressor at the gamma-crystallin (CRYGF) promoter, repressing it to ~10% of basal activity; functional assays define a Six3-responsive element between -101 and -123, and Six3 and Prox1 act antagonistically on CRYG promoters.\",\n      \"method\": \"Cell transfection reporter assay, randomly mutated promoter fragment analysis\",\n      \"journal\": \"Nucleic acids research\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reporter gene assays with deletion mapping; single lab, multiple constructs\",\n      \"pmids\": [\"11139622\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2001,\n      \"finding\": \"Six3 promotes formation of ectopic optic vesicle-like structures in the hindbrain-midbrain region of developing mouse embryos upon ectopic expression; Six3 expression in the murine lens placodal ectoderm is controlled by Pax6.\",\n      \"method\": \"Ectopic Six3 expression in mouse embryos, analysis of Pax6 mutants\",\n      \"journal\": \"Developmental dynamics\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — in vivo gain-of-function with phenotypic readout plus epistasis with Pax6; single lab\",\n      \"pmids\": [\"11458394\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2001,\n      \"finding\": \"NOR-1 (NR4A3) orphan nuclear receptor interacts with Six3 in vitro and in yeast; the interaction requires the DNA binding and AF2 domains of NOR-1; Six3 negatively regulates NOR-1 transcriptional activity through the NBRE response element in a dose-dependent manner.\",\n      \"method\": \"Yeast two-hybrid, GST pulldown, cotransfection reporter assay\",\n      \"journal\": \"Developmental neuroscience\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — GST pulldown and cotransfection in single lab; multiple methods but no reciprocal Co-IP or structural confirmation\",\n      \"pmids\": [\"11173923\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2002,\n      \"finding\": \"Grg4 and Grg5, mouse Groucho homologs, physically interact with Six3 (and Six6); interaction requires the Q domain of Grg5 and a conserved phenylalanine in an eh1-like motif in the Six domain of Six3; Six3 acts as a potent transcriptional repressor via this interaction, and this interaction is required for Six3 auto-repression; disruption of the Groucho-interaction domain prevents lens placode invagination in chick and alters photoreceptor phenotype in rat retina.\",\n      \"method\": \"Co-immunoprecipitation, yeast two-hybrid, PCR DNA-binding motif identification, retroviral infection of rat retinae, chick in ovo electroporation with wild-type vs. eh1-mutant Six3\",\n      \"journal\": \"Development\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — reciprocal Co-IP plus in vivo mutagenesis rescue experiments in two model systems; multiple orthogonal methods in one study\",\n      \"pmids\": [\"12050133\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2002,\n      \"finding\": \"Both Six3 and Six6 directly interact with TLE1 (Groucho family) and AES via the Six domain QD domain interface; Six3 additionally interacts with TLE proteins via the WDR domain; gain-of-function in medaka shows synergistic activity between SIX3/SIX6 and TLE1, while AES abrogates SIX3/6 overexpression phenotypes.\",\n      \"method\": \"Yeast two-hybrid with Six3/Six6 as baits, biochemical and mutational analysis, gain-of-function in medaka\",\n      \"journal\": \"Development\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — yeast two-hybrid plus in vivo functional assays; replicated finding from two independent labs (also PMID 12050133)\",\n      \"pmids\": [\"12441302\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2002,\n      \"finding\": \"Pax6 and Six3 mutually activate each other's expression in the developing mouse lens; both transcription factors bind regulatory sequences of the counterpart gene in vitro and in transgenic approaches; Six3 expression in lenses of Pax6 heterozygous mice is specifically reduced, and lens-specific Six3 expression rescues the Pax6 haploinsufficient lens phenotype by activating platelet-derived growth factor alpha-R/cyclin D1 signaling.\",\n      \"method\": \"In vitro DNA-binding assays, transgenic mouse rescue experiments, cyclin D1 pathway analysis\",\n      \"journal\": \"PNAS\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — in vitro binding plus transgenic rescue; multiple orthogonal methods establishing direct mutual regulatory relationship\",\n      \"pmids\": [\"12072567\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2003,\n      \"finding\": \"Six3 is a direct negative regulator of Wnt1 expression in the anterior neuroectoderm; in Six3-/- mice Wnt1 expression is rostrally expanded; ectopic Six3 expression in chick and zebrafish represses Wnt1; in vivo and in vitro DNA-binding assays confirm direct Six3 binding to Wnt1 regulatory sequences; Six3 rescues the headless/tcf3 zebrafish mutant phenotype through Wnt repression.\",\n      \"method\": \"Six3 knockout mice, ectopic Six3 expression in chick/zebrafish, in vivo and in vitro DNA-binding assays, phenotypic rescue of headless/tcf3 mutants\",\n      \"journal\": \"Genes & development\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — loss-of-function mouse + gain-of-function in two model organisms + direct DNA-binding assay + genetic epistasis rescue; multiple labs implicitly through zebrafish and chick systems\",\n      \"pmids\": [\"12569128\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2003,\n      \"finding\": \"Six3 acts as a cofactor for the NOR-1 (NR4A3) orphan nuclear receptor; Six3 binds the DNA-binding domain of NOR-1 and the EWS domain of EWS/NOR-1 via its homeodomain in vitro; Six3 stimulates NOR-1 transcriptional activity but represses EWS/NOR-1 activity in cotransfection assays.\",\n      \"method\": \"GST fusion protein assays, mammalian two-hybrid, cotransfection reporter assays in immortalized chondrocytes\",\n      \"journal\": \"Cancer research\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — GST pulldown + mammalian two-hybrid + reporter assay; single lab, multiple methods\",\n      \"pmids\": [\"12543801\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2004,\n      \"finding\": \"Six3 physically competes with Cdt1 to bind geminin (the DNA replication inhibitor); Six3 efficiently displaces Cdt1 from geminin, revealing a non-transcriptional mechanism by which Six3 promotes cell proliferation in retinal precursors; overexpression of geminin in medaka induces forebrain/eye defects rescued by Six3; loss of geminin potentiates Six3 gain-of-function phenotypes.\",\n      \"method\": \"Yeast two-hybrid, direct protein competition binding assays, medaka overexpression/loss-of-function genetics\",\n      \"journal\": \"Nature\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — direct in vitro competition binding assay plus in vivo genetic rescue/phenotype in medaka; multiple orthogonal methods in one high-impact study\",\n      \"pmids\": [\"14973488\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2004,\n      \"finding\": \"Three HPE-associated SIX3 homeodomain mutations have distinct functional consequences: L226V does not alter interaction with NOR-1; V250A produces a highly unstable protein; R257P abolishes in vivo interaction with NOR-1, suggesting different mutations affect different signaling pathways.\",\n      \"method\": \"GST pulldown assays, transient cotransfection in Neuro-2a cells, reporter assays\",\n      \"journal\": \"Human mutation\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — GST pulldown + reporter assay in cell lines; single lab, functional consequences of specific mutations defined\",\n      \"pmids\": [\"15523651\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2005,\n      \"finding\": \"Six3 promotes anterior neural plate expansion in Xenopus and zebrafish through transcriptional regulation of cell cycle regulators cyclinD1 and p27Xic1, as well as anti-neurogenic genes Zic2 and Xhairy2; Six3 also represses Bmp4 expression in adjacent ectoderm, and can expand the anterior neural plate even in the presence of cell cycle inhibitors, acting via BMP antagonism; Six3 cannot induce neural tissue alone but can do so in combination with Otx2.\",\n      \"method\": \"Ectopic Six3 expression in Xenopus and zebrafish, cell cycle inhibitor treatment, RT-PCR/in situ hybridization, chordino mutant rescue\",\n      \"journal\": \"Development\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — gain-of-function in two model organisms with multiple molecular readouts and pharmacological dissection; multiple orthogonal approaches\",\n      \"pmids\": [\"15843413\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2005,\n      \"finding\": \"Six3 mediates cell proliferation in the developing forebrain by sequestering Geminin from Cdt1; Lhx2 can rescue forebrain size reduction caused by six3 morpholino knockdown in zebrafish, but Six3b cannot rescue Lhx2 knockdown, placing Lhx2 downstream of Six3 in a parallel/alternative pathway for forebrain proliferation.\",\n      \"method\": \"Antisense morpholino knockdown in zebrafish, caged-mRNA photoactivation, head-specific overexpression, genetic epistasis\",\n      \"journal\": \"Developmental biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — morpholino + rescue experiments with photoactivatable mRNA; genetic epistasis established; single lab\",\n      \"pmids\": [\"16226737\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2005,\n      \"finding\": \"In developing mice, Six3 expression in the pre-placode lens ectoderm is initially Pax6-independent but subsequently becomes Pax6-dependent for both expression and nuclear localization; an in vitro protein-protein interaction is detected between Six3 and Eya1.\",\n      \"method\": \"Immunohistochemistry in Pax6 mutant mice, in vitro protein interaction assay\",\n      \"journal\": \"Gene expression patterns\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — in vitro pulldown for Six3-Eya1 interaction; Pax6-dependence of nuclear localization from IHC in mutant mice; single lab\",\n      \"pmids\": [\"16024294\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2006,\n      \"finding\": \"Six3 directly activates Pax6 and Sox2 expression in the presumptive lens ectoderm (PLE); conditional deletion of Six3 in the PLE disrupts lens induction and specification, downregulates Pax6, and eliminates Sox2; ChIP, EMSA, and luciferase reporter assays confirm direct Six3 binding to Pax6 and Sox2 regulatory sequences; misexpression of Six3 in chick promotes ectopic ectodermal Pax6 expression.\",\n      \"method\": \"Conditional knockout mice, ChIP, EMSA, luciferase reporter assays, misexpression in chick embryos\",\n      \"journal\": \"EMBO journal\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — ChIP + EMSA + reporter assay + conditional KO + in vivo misexpression; multiple orthogonal methods in single rigorous study\",\n      \"pmids\": [\"17066077\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2007,\n      \"finding\": \"Six3 inactivation causes progressive caudalization of the diencephalon; at 15-17 somites, Wnt1 expression is anteriorly expanded in Six3-null brains; Six3;Wnt1 double-null mice reveal that Six3-mediated repression of Wnt1 is necessary for formation of the rostral diencephalon, and that Six3 activity is required for telencephalon formation.\",\n      \"method\": \"Six3 knockout, Six3;Wnt1 double knockout mice, in situ hybridization\",\n      \"journal\": \"Development\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — double mutant genetic epistasis with defined molecular phenotype; replicated across two knockout models in single lab\",\n      \"pmids\": [\"18094027\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2007,\n      \"finding\": \"MTA1 physically interacts with Six3 chromatin in a histone deacetylase (HDAC)-dependent manner, leading to transcriptional suppression of Six3; MTA1 is also a Six3-interacting corepressor contributing to self-negative regulation of Six3 transcription; loss of MTA1 in null mice leads to elevated Six3 and enhanced recruitment of Six3 to the rhodopsin promoter; Six3 homeodomain binds specific DNA elements in the rhodopsin promoter to stimulate rhodopsin transcription; Six3 cooperates with Crx or NRL to stimulate rhodopsin-luc transcription; HPE-associated Six3 deletion mutations in helix 3 of the homeodomain abolish rhodopsin promoter binding.\",\n      \"method\": \"ChIP, co-immunoprecipitation, MTA1-null mice, knockdown in rat retinal ganglion cells, luciferase reporter assays with HPE mutations\",\n      \"journal\": \"PNAS\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — ChIP + Co-IP + null mouse model + knockdown + reporter assay + HPE mutation functional testing; multiple orthogonal methods in one study\",\n      \"pmids\": [\"17666527\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2007,\n      \"finding\": \"Six3 regulates diencephalic Nodal signaling activity; reduction of Six3 function causes brain-specific deregulation of Nodal pathway activity resulting in epithalamic laterality defects; misexpression and genetic epistasis in zebrafish indicate Six3 acts in the neuroectoderm to establish bilateral repression of Nodal activity, which is subsequently alleviated ipsilaterally by left-side Nodal signaling from lateral plate mesoderm.\",\n      \"method\": \"Zebrafish morpholino knockdown, Six3 misexpression, genetic epistasis experiments\",\n      \"journal\": \"Neuron\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — morpholino knockdown + misexpression + genetic epistasis; single lab, multiple methods\",\n      \"pmids\": [\"17678854\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2008,\n      \"finding\": \"Six3 directly binds and activates the Shh brain enhancer-2 (SBE2) located 460 kb upstream of SHH in the hypothalamus; HPE-causing Six3 alterations fail to bind and activate SBE2; DNA affinity-capture assay identified Six3 and Six6 as candidate regulators of Shh transcription; the mutant SBE2 sequence from an HPE patient shows reduced Six3 binding affinity.\",\n      \"method\": \"DNA affinity-capture assay, transgenic mouse enhancer assay, Six3 HPE mutation binding analysis\",\n      \"journal\": \"Nature genetics\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — direct DNA-binding assay + transgenic enhancer assay + HPE mutation functional testing; multiple orthogonal methods in single study\",\n      \"pmids\": [\"18836447\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2008,\n      \"finding\": \"Haploinsufficiency of Six3 (by deletion of one allele or replacement with HPE-associated alleles) causes HPE in mice; Shh is a direct target of Six3 in the rostral diencephalon ventral midline (RDVM); reduced Six3 fails to activate Shh expression in the mutant RDVM, leading to HPE; a crossregulatory loop between Shh and Six3 exists in the ventral forebrain.\",\n      \"method\": \"Six3 heterozygous and knockin mouse models, ChIP for direct Six3-Shh target validation, zebrafish functional assays for HPE mutations\",\n      \"journal\": \"Developmental cell\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — ChIP confirming direct target + loss-of-function mouse models + zebrafish hypomorph assays + HPE allele knockin; multiple orthogonal methods, replicated across species\",\n      \"pmids\": [\"18694563\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2008,\n      \"finding\": \"89% of HPE-associated SIX3 mutations function as loss-of-function alleles in zebrafish assays; disease-associated single point mutations in the Groucho-binding eh1-like motif decrease function in all assays, confirming that Groucho co-repressor interaction is essential for human SIX3 function and HPE causation; truncated SIX3 proteins missing the homeodomain retain partial function.\",\n      \"method\": \"Zebrafish functional assays for 46 distinct SIX3 mutations, eh1 motif mutational analysis\",\n      \"journal\": \"Human molecular genetics\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — systematic functional characterization of 46 mutations in zebrafish assays; large-scale mutational analysis with clear mechanistic conclusions\",\n      \"pmids\": [\"18791198\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"EYA4 is co-immunoprecipitated with SIX3 from cells; SIX3 recruits EYA4 (normally cytoplasmic) to the nucleus; EYA4 cooperates with SIX3 as a transcriptional coactivator in reporter gene assays, establishing a physical and functional SIX3-EYA4 interaction.\",\n      \"method\": \"Co-immunoprecipitation, confocal microscopy for nuclear recruitment, reporter gene assays\",\n      \"journal\": \"Human mutation\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — Co-IP + confocal localization + reporter assay; single lab, three orthogonal methods\",\n      \"pmids\": [\"19606496\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"Six3 directly represses Wnt8b expression in the developing neuroretina; conditional deletion of Six3 causes ectopic rostral expansion of Wnt8b and failure of neuroretina specification; ectopic Wnt8b transgenic expression is sufficient to suppress neuroretina specification; ChIP identified Six3-responsive elements in the Wnt8b locus.\",\n      \"method\": \"Conditional Six3 knockout mice, ChIP, Wnt8b transgenic overexpression\",\n      \"journal\": \"Journal of clinical investigation\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — conditional KO + ChIP direct target validation + transgenic epistasis; multiple orthogonal methods in single rigorous study\",\n      \"pmids\": [\"20890044\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"MTA1s and MTA1 physically interact with Six3 chromatin and inhibit Six3 transcription in an HDAC-dependent manner, relieving Six3-mediated repression of Wnt1 promoter; deletion of MTA1s/MTA1 in MEFs results in upregulation of Six3 and downregulation of Wnt signaling; in MTA1s/MTA1-null mammary glands, increased Six3 corepressor complex is recruited to the Wnt1 promoter.\",\n      \"method\": \"Co-immunoprecipitation, ChIP in null MEFs and mammary glands, gain/loss-of-function experiments\",\n      \"journal\": \"Cancer research\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — ChIP + Co-IP + null mouse model + gain/loss-of-function; multiple orthogonal methods across cell and mouse models\",\n      \"pmids\": [\"20682799\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"The Six3 homeodomain binds to a TAATGTC motif (a newly defined recognition sequence distinct from the common TGATAC Six family motif) at multiple sites within the six3a promoter with high affinity; ChIP confirms Six3a binding to promoter fragments containing clustered TAATGTC sites in vivo; these sites mediate autoregulation in zebrafish embryos.\",\n      \"method\": \"In vitro DNA-binding affinity assays, single-nucleotide substitution analysis, ChIP, transient reporter assays in zebrafish embryos\",\n      \"journal\": \"FEBS journal\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — in vitro binding assay with mutagenesis + ChIP in vivo + reporter assay in embryos; multiple orthogonal methods in single study\",\n      \"pmids\": [\"20193042\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"Six3 is required for ependymal cell maturation during postnatal brain development; in Six3's absence, ependymal cells fail to suppress radial glia characteristics, resulting in a defective lateral wall, abnormal neuroblast migration and differentiation, and hydrocephaly.\",\n      \"method\": \"Six3 conditional knockout in ependymal cells, histological and molecular marker analysis\",\n      \"journal\": \"Development\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — conditional knockout with specific cellular and molecular phenotypic readouts; single lab\",\n      \"pmids\": [\"22071110\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"In zebrafish, Six3 (six3b and six7) cooperates with Hedgehog signaling to specify ventral telencephalon; Six3 promotes ventral telencephalic fates through transient regulation of foxg1a expression and repression of Wnt/β-catenin signaling; Six3 overexpression can compensate for loss of Hh signaling in isl1- but not nkx2.1b-positive cells, indicating a Hh-independent role for Six3.\",\n      \"method\": \"Zebrafish morpholino knockdown of six3b and six7, overexpression, Hh pathway inhibition/activation assays\",\n      \"journal\": \"Development\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — morpholino knockdown + overexpression + pathway epistasis; single lab, multiple functional assays\",\n      \"pmids\": [\"22736245\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"Sox2 directly regulates a long-range forebrain enhancer to activate Six3 expression in the rostral diencephalon; biochemical and genetic evidence establish a direct regulatory link between Sox2 and Six3 during forebrain development.\",\n      \"method\": \"Genomic ChIP-seq for Sox2 binding, in vivo transgenic enhancer assay, genetic epistasis\",\n      \"journal\": \"Developmental biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — ChIP-seq + transgenic enhancer assay + genetic evidence; multiple orthogonal methods in single study\",\n      \"pmids\": [\"23792023\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"Six3 dosage determines HPE severity in mice: semilobar HPE results from severe downregulation of Shh expression in the rostral diencephalon ventral midline, while alobar HPE is caused by downregulation of Foxg1 expression in the anterior neural ectoderm; in vivo Shh pathway activation rescues semilobar but not alobar HPE.\",\n      \"method\": \"Novel hypomorphic Six3 allele mice, in vivo Shh pathway activation, gene expression analysis\",\n      \"journal\": \"Development\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — hypomorphic allele dosage series + pathway-specific rescue; mechanistically dissects two distinct downstream pathways\",\n      \"pmids\": [\"27770010\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"Six3 repression of R-spondin 2 (Rspo2) is required during optic vesicle morphogenesis and neuroretina differentiation; transient ectopic Rspo2 expression in the anterior neural plate of transgenic mouse embryos is sufficient to inhibit neuroretina differentiation; Six3-null cells exert a non-cell-autonomous repressive effect on optic vesicle formation.\",\n      \"method\": \"Six3-/- iPSC eye organoid, conditional null ESC organoid, in vivo transgenic Rspo2 overexpression, chimeric eye organoid assay\",\n      \"journal\": \"Cell reports\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — iPSC/ESC organoid models + in vivo transgenic epistasis + chimeric assay; multiple orthogonal methods\",\n      \"pmids\": [\"29117559\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"SIX3 directly binds to the promoter regions of AURKA and AURKB (aurora kinases A and B) to repress their transcription in a dose-dependent manner; SIX3 increases p53 activity at the post-translational level through negative regulation of AURKA or AURKB; SIX3 overexpression does not affect AURKA-AURKB protein stabilization interactions.\",\n      \"method\": \"ChIP, luciferase reporter assay, Co-IP for AURKA-AURKB interaction, flow cytometry, colony formation/intracranial xenograft assays\",\n      \"journal\": \"Journal of hematology & oncology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — ChIP + reporter assay confirming direct promoter binding; functional assays in astrocytoma cells; single lab\",\n      \"pmids\": [\"28595628\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"Six3 in a small population of anteroventral optic vesicle progenitors at E8.5 is required for neuroretinal specification; Six3 deletion in these progenitors causes rostral expansion of Wnt8b and drastic reduction of Fgf8/MAPK signaling, ablating neuroretinal specification without affecting RPE; Six3-Cre positive progenies are found in neuroretina and optic stalk but not RPE.\",\n      \"method\": \"Lineage tracing with Six3-Cre in wild-type and Six3-deficient mice, gene expression analysis by ISH/immunostaining\",\n      \"journal\": \"Developmental biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — lineage tracing + conditional KO + molecular pathway readouts; mechanistically precise mapping of Six3 function to specific progenitor population\",\n      \"pmids\": [\"28579317\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"SIX3 forms a complex with LSD1/NuRD(MTA3) identified by affinity purification and mass spectrometry; this complex represses WNT1 and FOXC2 (involved in EMT) as identified by ChIP-on-chip genome-wide analysis; the SIX3/LSD1/NuRD(MTA3) complex inhibits carcinogenesis and metastasis in breast cancer cells.\",\n      \"method\": \"Affinity purification + mass spectrometry, ChIP-on-chip, in vitro and in vivo functional assays\",\n      \"journal\": \"Theranostics\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — AP-MS complex identification + genome-wide ChIP-on-chip; multiple orthogonal methods in single study\",\n      \"pmids\": [\"29463994\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"SP8 and SP9 directly activate Six3 expression in a spatially restricted LGE subventricular zone domain; ChIP-seq shows SP9 directly binds the promoter and a putative enhancer of Six3; conditional deletion of Six3 prevents formation of most D2 MSNs, phenocopying Sp8/9 double mutants.\",\n      \"method\": \"Conditional knockout mice (Sp8/Sp9 and Six3), ChIP-seq, in situ hybridization, immunostaining\",\n      \"journal\": \"Development\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — ChIP-seq for direct binding + conditional knockout phenocopy; multiple methods in single study\",\n      \"pmids\": [\"29967281\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"Six3 and Six6 are jointly required for maintenance of multipotent neuroretinal progenitors; double knockout retinas show ectopic upregulation of Wnt3a, Fzd1, Otx1 and Cdon (ciliary margin markers) and loss of neuroretinal progenitor markers Sox2, Notch1, Otx2; stimulation of Wnt/β-catenin signaling promotes ciliary margin progenitors at the cost of neuroretinal identity, indicating Six3 and Six6 together directly or indirectly suppress Wnt/β-catenin signaling.\",\n      \"method\": \"Six3/Six6 double conditional knockout mice, Wnt-3a and GSK3β inhibitor treatment of eye cups, gene expression analysis\",\n      \"journal\": \"Cell reports\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — double conditional knockout + pharmacological Wnt pathway manipulation + molecular markers; multiple orthogonal approaches\",\n      \"pmids\": [\"30485816\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"EGFR activation induces DNA methylation silencing of SIX3 through the MAPK pathway: activated ERK binds ZNF263, abrogates its ubiquitination and stabilizes it; ZNF263 binds the core SIX3 promoter and recruits the KAP1/HATS/DNMT corepressor complex inducing H3K27me3 and DNA methylation at the SIX3 promoter.\",\n      \"method\": \"Co-immunoprecipitation, ChIP, ubiquitination assay, MAPK pathway inhibition/activation, reporter assays\",\n      \"journal\": \"Oncogene\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — Co-IP + ChIP + ubiquitination assay + pathway epistasis; multiple orthogonal methods defining the upstream silencing mechanism\",\n      \"pmids\": [\"32051553\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"TRIM27 E3 ubiquitin ligase ubiquitinates and degrades SIX3 protein, activating Wnt/β-catenin signaling; SIX3 negatively regulates β-catenin, S100P, TGFB3, and MMP-9 expression in NSCLC cells.\",\n      \"method\": \"Ubiquitination assay, co-immunoprecipitation, loss/gain-of-function in NSCLC cells, XAV939 pathway inhibition\",\n      \"journal\": \"Aging\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — ubiquitination assay + Co-IP + functional rescue; single lab, multiple methods\",\n      \"pmids\": [\"33264103\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"SIX3 suppression in human adult pancreatic islets by shRNA impairs insulin secretion; SIX3 loss leads to inappropriate expression of genes normally expressed in fetal β cells, adult α cells, and non-β cells, indicating SIX3 maintains developmental fate and suppresses non-β-cell gene programs; SIX2 and SIX3 regulate distinct target gene sets.\",\n      \"method\": \"shRNA knockdown in human adult islets, transcriptome analysis, chromatin accessibility studies\",\n      \"journal\": \"Genes & development\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — functional knockdown in primary human tissue with transcriptomic readout; chromatin accessibility data; single lab\",\n      \"pmids\": [\"33446570\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"Six3 functions in D2 MSN precursor cells to drive their differentiation; conditional deletion of Six3 blocks differentiation without affecting proliferation, and conditionally overexpressed Six3 promotes LGE precursor differentiation; abnormally differentiated D2 MSNs in Six3-KO are eliminated by apoptosis postnatally.\",\n      \"method\": \"Conditional Six3 knockout and overexpression in mice, BrdU/EdU proliferation assays, TUNEL apoptosis assay, immunostaining\",\n      \"journal\": \"Neuroscience bulletin\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — conditional KO + conditional OE + multiple cellular readouts; single lab\",\n      \"pmids\": [\"34014554\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"SIX3 is a homeodomain transcription factor that functions primarily as a transcriptional repressor (via direct interaction with Groucho/TLE family corepressors through an eh1-like motif in its Six domain) but also as a context-dependent activator; it directly represses Wnt1, Wnt8b, R-spondin 2, AURKA/B, and other targets while directly activating Shh (via SBE2 enhancer binding) and Pax6/Sox2 in the lens ectoderm, positioning Six3 at the top of regulatory cascades governing anterior neural plate specification, forebrain development, eye and neuroretina morphogenesis, and HPE pathogenesis; additionally, Six3 promotes cell proliferation through a non-transcriptional mechanism by competing with Cdt1 for geminin binding, and its activity is modulated by upstream regulators including MTA1 (HDAC-dependent chromatin silencing), TRIM27 (ubiquitin-mediated degradation), ZNF263/EGFR (epigenetic silencing via H3K27me3 and DNA methylation), and Sox2 (transcriptional activation via a long-range enhancer).\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"SIX3 is a homeodomain transcription factor that sits at the top of the gene-regulatory hierarchy specifying the anterior neural plate, forebrain, and eye, with both its Six domain and homeodomain required for activity [#0, #2, #19]. It acts predominantly as a Groucho/TLE-dependent transcriptional repressor, binding corepressors (Grg3/Grg4/Grg5, TLE1, AES) through an eh1-like motif in its Six domain; mutation of this motif simultaneously abolishes corepressor binding and developmental activity [#5, #9, #10]. Through this repressive activity SIX3 directly silences Wnt pathway components—Wnt1, Wnt8b, and R-spondin 2—to restrict caudalizing Wnt/\\u03b2-catenin signaling and permit rostral diencephalon, telencephalon, and neuroretina specification [#12, #20, #27, #34]. In a context-dependent activating mode, SIX3 binds and activates the long-range SHH brain enhancer SBE2 in the rostral diencephalon and directly activates Pax6 and Sox2 in the presumptive lens ectoderm to drive lens and eye induction [#19, #23, #24]. SIX3 also drives progenitor proliferation through a non-transcriptional mechanism, competing with Cdt1 for binding to the replication inhibitor geminin in retinal and forebrain precursors [#14, #17]. Its own expression is autoregulated via direct binding to a TAATGTC motif in its promoter and is set by upstream inputs including Sox2 and SP8/SP9 enhancer activation and MTA1/NuRD-dependent corepression [#21, #29, #32, #38]. Heterozygous loss-of-function mutations in human SIX3—including homeodomain and eh1-motif point mutations that disrupt DNA binding and corepressor interaction—cause holoprosencephaly (HPE2), with dosage determining severity through differential loss of Shh versus Foxg1 expression [#4, #24, #25, #33].\",\n  \"teleology\": [\n    {\n      \"year\": 1995,\n      \"claim\": \"Established SIX3 as an early anterior neural/eye-field homeobox factor acting upstream of and independently from Pax6, defining its position in the developmental hierarchy.\",\n      \"evidence\": \"In situ hybridization and expression analysis in Pax6 mutant mice\",\n      \"pmids\": [\"8575305\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No direct target genes identified\", \"Repressor versus activator function unresolved at this stage\"]\n    },\n    {\n      \"year\": 1999,\n      \"claim\": \"Demonstrated SIX3 is sufficient to induce eye-field programs by triggering ectopic lens and retinal primordia and revealed an autoregulatory feedback loop.\",\n      \"evidence\": \"Ectopic mRNA injection in medaka and zebrafish with target-gene in situ readouts\",\n      \"pmids\": [\"9025075\", \"9655819\", \"10090721\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Direct versus indirect target activation not distinguished\", \"Domain requirements for autoregulation not yet mapped\"]\n    },\n    {\n      \"year\": 1999,\n      \"claim\": \"Linked SIX3 to human disease, identifying homeodomain mutations as the cause of holoprosencephaly (HPE2).\",\n      \"evidence\": \"Mutational analysis of HPE patient families with functional prediction\",\n      \"pmids\": [\"10369266\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Functional consequences of mutations predicted, not measured\", \"Downstream pathway affected unknown\"]\n    },\n    {\n      \"year\": 2001,\n      \"claim\": \"Defined the molecular basis of SIX3 repression by showing it recruits Groucho/Grg corepressors through an eh1-like motif required for forebrain activity and autorepression.\",\n      \"evidence\": \"Yeast two-hybrid, Co-IP, eh1 motif mutagenesis with in vivo assays in zebrafish, chick, and rat retina\",\n      \"pmids\": [\"11401394\", \"12050133\", \"12441302\", \"11139622\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Direct genomic repression targets not yet identified\", \"Switch between repressor and activator modes unexplained\"]\n    },\n    {\n      \"year\": 2002,\n      \"claim\": \"Connected SIX3 to lens induction through a mutual cross-activation loop with Pax6 driving downstream proliferative signaling.\",\n      \"evidence\": \"In vitro DNA binding and transgenic mouse rescue of Pax6 haploinsufficiency\",\n      \"pmids\": [\"12072567\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Direct binding sites in the Pax6 locus not finely mapped here\", \"Temporal order of mutual activation incompletely resolved\"]\n    },\n    {\n      \"year\": 2003,\n      \"claim\": \"Identified Wnt1 as a direct repression target, establishing SIX3's role in restricting caudalizing Wnt signaling to pattern the anterior brain.\",\n      \"evidence\": \"Six3 knockout mice, gain-of-function in chick/zebrafish, DNA-binding assays, and headless/tcf3 rescue\",\n      \"pmids\": [\"12569128\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Full set of Wnt-pathway targets unknown\", \"Corepressor requirement at the Wnt1 locus not yet shown\"]\n    },\n    {\n      \"year\": 2004,\n      \"claim\": \"Revealed a non-transcriptional proliferative mechanism whereby SIX3 sequesters geminin from Cdt1 to license replication in neural/retinal precursors.\",\n      \"evidence\": \"Direct protein competition binding assays plus medaka overexpression/loss-of-function genetics\",\n      \"pmids\": [\"14973488\", \"16226737\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Quantitative contribution of this mechanism versus transcriptional outputs unclear\", \"Regulation of the SIX3-geminin interaction unknown\"]\n    },\n    {\n      \"year\": 2006,\n      \"claim\": \"Showed SIX3 directly activates Pax6 and Sox2 in the lens ectoderm, demonstrating a bona fide context-dependent activator function distinct from its repressive role.\",\n      \"evidence\": \"Conditional knockout, ChIP, EMSA, luciferase reporters, and chick misexpression\",\n      \"pmids\": [\"17066077\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Coactivator partners at activated loci not defined\", \"Determinants of activator versus repressor outcome unresolved\"]\n    },\n    {\n      \"year\": 2008,\n      \"claim\": \"Established SIX3 as a direct activator of SHH via the long-range SBE2 enhancer and mechanistically tied HPE mutations to failed Shh activation.\",\n      \"evidence\": \"DNA affinity-capture, transgenic enhancer assays, ChIP, and HPE allele knockin/mutation testing\",\n      \"pmids\": [\"18836447\", \"18694563\", \"18791198\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Coactivators enabling SHH activation not identified\", \"How a repressor-prone factor activates SBE2 not mechanistically resolved\"]\n    },\n    {\n      \"year\": 2010,\n      \"claim\": \"Extended the Wnt-repression program to Wnt8b in the neuroretina, establishing SIX3-mediated Wnt suppression as essential for neuroretina specification.\",\n      \"evidence\": \"Conditional knockout, ChIP, and Wnt8b transgenic epistasis\",\n      \"pmids\": [\"20890044\", \"20682799\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Whether one corepressor complex serves all Wnt targets unknown\", \"Cell-type specificity of target choice unexplained\"]\n    },\n    {\n      \"year\": 2010,\n      \"claim\": \"Defined SIX3 autoregulation at the DNA level by identifying a non-canonical TAATGTC recognition motif clustered in its own promoter.\",\n      \"evidence\": \"In vitro binding with single-nucleotide substitution, ChIP, and zebrafish reporter assays\",\n      \"pmids\": [\"20193042\", \"17666527\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Genome-wide preference for TAATGTC versus canonical sites unmeasured\", \"Structural basis of motif selectivity unknown\"]\n    },\n    {\n      \"year\": 2016,\n      \"claim\": \"Resolved how SIX3 dosage dictates HPE severity by separating Shh-dependent (semilobar) from Foxg1-dependent (alobar) phenotypes.\",\n      \"evidence\": \"Hypomorphic allele dosage series with pathway-specific in vivo Shh rescue\",\n      \"pmids\": [\"27770010\", \"20193042\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Whether Foxg1 is a direct SIX3 target not established\", \"Threshold mechanism distinguishing the two pathways unknown\"]\n    },\n    {\n      \"year\": 2017,\n      \"claim\": \"Mapped SIX3 function to a defined anteroventral optic vesicle progenitor population and added R-spondin 2 to its directly repressed Wnt-modulating targets.\",\n      \"evidence\": \"Lineage tracing, conditional KO, iPSC/ESC organoids, and Rspo2 transgenic epistasis\",\n      \"pmids\": [\"28579317\", \"29117559\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Mechanism of non-cell-autonomous repression of optic vesicle formation unclear\", \"Direct binding at the Rspo2 locus not detailed\"]\n    },\n    {\n      \"year\": 2018,\n      \"claim\": \"Defined the upstream transcriptional and epigenetic control of SIX3, identifying Sox2 and SP8/SP9 as direct enhancer/promoter activators and the LSD1/NuRD(MTA3) complex as a SIX3 partner controlling Wnt1/EMT genes.\",\n      \"evidence\": \"ChIP-seq, transgenic enhancer assays, conditional knockouts, and AP-MS complex identification\",\n      \"pmids\": [\"23792023\", \"29967281\", \"29463994\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Composition of the SIX3 corepressor complex in neural contexts not fully defined\", \"Whether NuRD recruitment generalizes to developmental targets unknown\"]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"Established post-transcriptional and epigenetic silencing of SIX3 as a tumor-relevant axis via EGFR/MAPK-ZNF263-driven promoter methylation and TRIM27-mediated protein degradation.\",\n      \"evidence\": \"Co-IP, ChIP, ubiquitination assays, and pathway epistasis in cancer cells\",\n      \"pmids\": [\"32051553\", \"33264103\", \"28595628\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Physiological relevance of these regulators in normal development untested\", \"Direct SIX3 binding at AURKA/AURKB versus indirect effects partly unresolved\"]\n    },\n    {\n      \"year\": 2021,\n      \"claim\": \"Revealed a postnatal cell-identity maintenance role, with SIX3 sustaining adult \\u03b2-cell and D2 MSN differentiation programs and suppressing alternative fates.\",\n      \"evidence\": \"shRNA knockdown in human islets with transcriptomics, and conditional KO/overexpression in mouse striatum\",\n      \"pmids\": [\"33446570\", \"34014554\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct target genes maintaining cell identity not defined\", \"Whether identity maintenance uses the same corepressor machinery as development unknown\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"The molecular determinant that switches SIX3 between Groucho-dependent repression and context-specific activation of SHH/Pax6/Sox2 remains unresolved.\",\n      \"evidence\": null,\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No structural model explaining repressor/activator partner selection\", \"Coactivators required for SBE2/Pax6 activation not identified\", \"How upstream chromatin state biases target choice unknown\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0140110\", \"supporting_discovery_ids\": [5, 9, 12, 19, 23, 35]},\n      {\"term_id\": \"GO:0003677\", \"supporting_discovery_ids\": [12, 19, 23, 27, 29, 35]},\n      {\"term_id\": \"GO:0140313\", \"supporting_discovery_ids\": [14, 17]},\n      {\"term_id\": \"GO:0098772\", \"supporting_discovery_ids\": [8, 13, 26]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005634\", \"supporting_discovery_ids\": [18, 26]},\n      {\"term_id\": \"GO:0005654\", \"supporting_discovery_ids\": [21, 28, 37]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-1266738\", \"supporting_discovery_ids\": [12, 19, 20, 24, 36]},\n      {\"term_id\": \"R-HSA-74160\", \"supporting_discovery_ids\": [5, 19, 23, 27, 35]},\n      {\"term_id\": \"R-HSA-162582\", \"supporting_discovery_ids\": [12, 27, 34, 39, 41]},\n      {\"term_id\": \"R-HSA-1643685\", \"supporting_discovery_ids\": [4, 24, 33, 35, 40]},\n      {\"term_id\": \"R-HSA-1640170\", \"supporting_discovery_ids\": [14, 16, 17]}\n    ],\n    \"complexes\": [\n      \"SIX3/LSD1/NuRD(MTA3)\",\n      \"SIX3-Groucho/TLE corepressor complex\"\n    ],\n    \"partners\": [\n      \"TLE1\",\n      \"AES\",\n      \"GEMININ\",\n      \"PAX6\",\n      \"EYA4\",\n      \"MTA1\",\n      \"NR4A3\",\n      \"TRIM27\"\n    ],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":7,"faith_total":7,"faith_pct":100.0}}