{"gene":"PAX2","run_date":"2026-04-29T11:37:57","timeline":{"discoveries":[{"year":1996,"finding":"Loss-of-function (knockout) of Pax2 in mice results in agenesis of the optic chiasma (ipsilateral optic tracts), coloboma due to failure of optic fissure closure, and agenesis of the cochlea and spiral ganglion, establishing Pax2 as a major regulator of patterning and morphogenesis in the eye and inner ear.","method":"Pax2 null mutant mice; paint-fill, gene expression analysis, histology","journal":"Development","confidence":"High","confidence_rationale":"Tier 2 — clean KO with defined cellular phenotypes; replicated across multiple subsequent studies","pmids":["8951055"],"is_preprint":false},{"year":2002,"finding":"Pax2 and Pax8 together are required to specify the nephric lineage: double-mutant mouse embryos lacking both genes fail to form the pronephros or any subsequent nephric structures, fail to undergo mesenchymal-epithelial transition, and fail to initiate Lim1 and c-Ret expression. Retroviral misexpression of Pax2 alone was sufficient to induce ectopic nephric structures in chick intermediate mesoderm.","method":"Pax2/Pax8 double-mutant mice; retroviral misexpression in chick embryos; gene expression analysis","journal":"Genes & Development","confidence":"High","confidence_rationale":"Tier 2 — reciprocal gain/loss-of-function with defined molecular and cellular readouts; multiple orthogonal methods","pmids":["12435636"],"is_preprint":false},{"year":1993,"finding":"Deregulated (gain-of-function) Pax-2 expression in transgenic mice causes histologically abnormal, dysfunctional renal epithelium with properties similar to congenital nephrotic syndrome, demonstrating that repression of Pax-2 is required for normal kidney development and that persistent Pax-2 expression restricts differentiation potential of renal epithelial cells.","method":"Transgenic mice with deregulated Pax-2 expression; histological and functional analysis","journal":"Nature","confidence":"High","confidence_rationale":"Tier 2 — clean gain-of-function with defined phenotype, replicated in four independent transgenic embryos/one line","pmids":["8383297"],"is_preprint":false},{"year":2008,"finding":"PAX2 acts as a crucial mediator of estrogen receptor (ER)-dependent transcriptional repression of ERBB2/HER-2 in response to tamoxifen in breast cancer cells; PAX2 and the ER co-activator AIB-1/SRC-3 compete for binding and regulation of ERBB2 transcription at a cis-regulatory element within the ERBB2 gene.","method":"ChIP, co-IP, reporter assays, siRNA knockdown in human breast cancer cell lines","journal":"Nature","confidence":"High","confidence_rationale":"Tier 2 — multiple orthogonal methods (ChIP, co-IP, reporter assay, KD) in a single rigorous study","pmids":["19005469"],"is_preprint":false},{"year":1995,"finding":"WT1 protein directly represses Pax-2 transcription by binding to three high-affinity sites in the 5' untranslated Pax-2 leader sequence, as demonstrated by DNase I footprinting and co-transfection/reporter assays; this coincides with down-regulation of Pax-2 in developing podocyte precursors.","method":"DNase I footprinting, co-transfection with CAT reporter constructs, immunostaining","journal":"Development","confidence":"High","confidence_rationale":"Tier 1–2 — in vitro binding assay + functional reporter assay + in vivo expression correlation","pmids":["7720589"],"is_preprint":false},{"year":1996,"finding":"Pax-2 transactivation requires amino acids 279–373 in the C-terminus; the conserved octapeptide sequence acts as a repression domain that down-modulates Pax-2 transactivation in heterologous contexts.","method":"Deletion/mutation mapping with GAL4 fusion reporter assays in tissue culture cells","journal":"Journal of Biological Chemistry","confidence":"High","confidence_rationale":"Tier 1 — domain mapping by mutagenesis with functional reporter assay","pmids":["8702876"],"is_preprint":false},{"year":2000,"finding":"PTIP, a novel BRCT domain-containing protein, directly binds to the Pax2 activation domain (but not when the octapeptide repression domain is present), as shown by yeast two-hybrid, in vitro binding, and co-localization in tissue culture nuclei/active chromatin/nuclear matrix fraction, linking Pax2 to active chromatin machinery.","method":"Yeast two-hybrid, in vitro pulldown, co-localization in tissue culture cells, nuclear fractionation","journal":"Nucleic Acids Research","confidence":"High","confidence_rationale":"Tier 2 — reciprocal binding demonstrated by multiple methods; interaction confirmed in cells","pmids":["10908331"],"is_preprint":false},{"year":2003,"finding":"The Groucho/TLE family protein Grg4 interacts with Pax2 to suppress transactivation by specifically inhibiting JNK-mediated phosphorylation of the Pax2 activation domain; this suppression depends on Pax2 binding to its target DNA and is independent of histone deacetylation.","method":"Co-IP, in vitro kinase assay, reporter assay, mutagenesis, HDAC inhibitor treatment","journal":"EMBO Journal","confidence":"High","confidence_rationale":"Tier 1–2 — in vitro kinase assay + co-IP + reporter assay with mutagenesis; multiple orthogonal methods","pmids":["14532124"],"is_preprint":false},{"year":2015,"finding":"The phosphatase PPM1B is a component of the Groucho4 repressor complex recruited by Pax2 to chromatin; PPM1B dephosphorylates the Pax2 activation domain and displaces the adaptor protein PTIP, thereby inhibiting H3K4 methylation and switching Pax2 from a transcriptional activator to a repressor. Loss of PPM1B prevents Groucho-mediated gene repression.","method":"Co-IP, ChIP, reporter assays, siRNA knockdown, histone methylation analysis","journal":"Journal of Biological Chemistry","confidence":"High","confidence_rationale":"Tier 1–2 — multiple orthogonal methods establishing enzymatic mechanism with functional consequence","pmids":["25631048"],"is_preprint":false},{"year":2005,"finding":"PAX2 directly activates WNT4 transcription during kidney development by binding to three specific recognition motifs in the WNT4 promoter, as shown by EMSA, co-transfection reporter assays, and reduced Wnt4 mRNA in heterozygous Pax2 mutant mouse kidneys.","method":"EMSA, co-transfection reporter assay, RT-PCR in Pax2 heterozygous fetal kidneys","journal":"Journal of Biological Chemistry","confidence":"High","confidence_rationale":"Tier 1–2 — in vitro DNA binding + reporter assay + in vivo genetic confirmation","pmids":["16368682"],"is_preprint":false},{"year":2006,"finding":"PAX2 directly binds the neuronal apoptosis inhibitory protein (NAIP) gene promoter and activates NAIP transcription (~7-fold in vitro; 4-fold increase in stably transfected HEK293 cells); Naip mRNA is reduced 50% in heterozygous Pax2 mutant mice, and NAIP suppresses caspase-3/7-mediated apoptosis in collecting duct cells.","method":"EMSA, reporter assay, stable transfection, RT-PCR in Pax2 mutant mice, caspase activity assay","journal":"American Journal of Physiology: Renal Physiology","confidence":"High","confidence_rationale":"Tier 1–2 — in vitro DNA binding + reporter + in vivo genetic confirmation with functional apoptosis readout","pmids":["16735463"],"is_preprint":false},{"year":2006,"finding":"Inducible podocyte-specific expression of PAX2 in adult mice represses WT1 and consequently reduces nephrin expression, causing end-stage renal failure; recruitment of the Groucho-related protein TLE4 may convert Pax2 into a transcriptional repressor of Wt1.","method":"Inducible transgenic mouse model (Cre-lox), immunostaining, gene expression analysis","journal":"Current Biology","confidence":"High","confidence_rationale":"Tier 2 — inducible in vivo model with defined molecular targets and phenotypic readout","pmids":["16631587"],"is_preprint":false},{"year":2005,"finding":"Pax2 directly regulates Brn1 (Pou3f3) transcription at the mid-hindbrain boundary via two functional Pax2-binding sites in the Brn1 promoter and upstream regulatory element, as shown by reporter assay; Brn1 in turn is implicated in Fgf8 gene regulation.","method":"cDNA microarray with FACS-sorted GFP+ cells from Pax2-/- embryos, lacZ reporter transgene analysis, mutagenesis of Pax2-binding sites, dominant-negative electroporation in chick","journal":"Development","confidence":"High","confidence_rationale":"Tier 2 — expression profiling combined with functional reporter assay and mutagenesis","pmids":["15872005"],"is_preprint":false},{"year":2000,"finding":"Pax2 and homeodomain proteins cooperatively regulate the Pax5 mhb enhancer through direct binding; mutation of the Pax2/5/8 binding site in the Pax5 enhancer reduces transgene expression at the midbrain-hindbrain boundary, and Pax2 mutant embryos show reduced Pax5 expression specifically in regions dependent on the Pax-binding site.","method":"Transgenic reporter assay, site-directed mutagenesis of enhancer binding sites, protein binding assays with mhb-specific extracts, analysis in Pax2 mutant embryos","journal":"Development","confidence":"High","confidence_rationale":"Tier 1–2 — protein binding + functional mutagenesis + in vivo genetic validation","pmids":["10662641"],"is_preprint":false},{"year":2002,"finding":"The activation and maintenance of Pax2 expression at the midbrain-hindbrain boundary are controlled by separate enhancers: an early enhancer (~-3.7 kb, dependent on homeodomain/POU binding sites including Oct3/4) and two late enhancers (~-4.1 kb and ~-2.8 kb); the proximal late enhancer contains a functional Pax2/5/8-binding site mediating auto- and cross-regulatory maintenance.","method":"Transgenic reporter analysis, site-directed mutagenesis, BAC transgene deletion analysis, Oct3/4 binding assay","journal":"Development","confidence":"High","confidence_rationale":"Tier 1–2 — functional enhancer dissection with mutagenesis and in vivo transgenic validation","pmids":["11807024"],"is_preprint":false},{"year":2014,"finding":"p53 directly occupies chromatin regions of the Pax2 promoter and gene in embryonic kidneys (ChIP-Seq), stimulates Pax2 promoter activity in transfection assays, and p53 knockout mice show reduced Pax2 in nephron progenitors; reducing p53 gene dosage worsens renal hypoplasia in Pax2+/- mice, establishing a p53–Pax2 epistatic relationship in nephrogenesis.","method":"ChIP-Seq, transient transfection reporter assay, p53 KO and conditional KO mice, siRNA knockdown in cultured metanephric mesenchyme cells","journal":"PLoS One","confidence":"High","confidence_rationale":"Tier 1–2 — ChIP-Seq + reporter assay + multiple genetic models with defined phenotypic readout","pmids":["22984579"],"is_preprint":false},{"year":2000,"finding":"Tlx (orphan nuclear receptor) directly regulates Pax2 transcription: Tlx binds a conserved site in the Pax2 promoter, Tlx-null mice show reduced Pax2 expression, and Pax2 is identified as a direct transcriptional target of Tlx in retinal development.","method":"Tlx targeted knockout mice, P19 neural precursor screen, promoter binding assay, sequence conservation analysis","journal":"PNAS","confidence":"Medium","confidence_rationale":"Tier 2 — in vivo genetic evidence + promoter binding, but functional reporter assay with mutagenesis not detailed","pmids":["10706625"],"is_preprint":false},{"year":1996,"finding":"Pax-2 proteins (2A and 2B isoforms) bind DNA through the paired domain with similar specificity; chromatin immunoprecipitation from embryonic neural tube identified novel in vivo Pax-2 binding sites sharing homology with Pax-5 and Pax-2 consensus sequences.","method":"Chromatin immunoprecipitation from embryonic neural tube, in vitro DNA binding assays with recombinant Pax-2","journal":"Journal of Biological Chemistry","confidence":"Medium","confidence_rationale":"Tier 2 — ChIP from native tissue + in vitro binding validation; early chromatin precipitation method","pmids":["8626478"],"is_preprint":false},{"year":2011,"finding":"PHD3 (prolyl hydroxylase domain protein 3) physically binds to Pax2 protein and mediates its proteasomal destruction; inhibition of PHD3 hydroxylase activity increases Pax2 protein but not mRNA levels, identifying PHD3 as a post-translational negative regulator of Pax2 stability.","method":"Co-IP, PHD3 inhibitor treatment, Western blot for Pax2 protein vs. mRNA levels","journal":"Biochemical and Biophysical Research Communications","confidence":"Medium","confidence_rationale":"Tier 3 — single lab, co-IP + inhibitor treatment; proteasomal mechanism inferred but not fully reconstituted","pmids":["21575608"],"is_preprint":false},{"year":2008,"finding":"PAX2 directly binds to and transactivates the WNT5A promoter in HEK293 cells, as shown by transactivation assays and EMSA; reduced WNT5A expression in Wilms tumor correlates with blastemal predominance.","method":"Chromatin enrichment, ChIP, EMSA, transactivation assay in HEK293 cells","journal":"Neoplasia","confidence":"Medium","confidence_rationale":"Tier 2 — EMSA + functional reporter assay in a single study","pmids":["19048125"],"is_preprint":false},{"year":2011,"finding":"PAX2 binds to the ADAM10 promoter and regulates ADAM10 protein expression in renal cancer cells; PAX2 silencing leads to reduced ADAM10, reduced L1-CAM shedding, altered EMT markers, and activation of PI3K/Akt pathway via L1-CAM.","method":"ChIP (PAX2 binding to ADAM10 promoter), siRNA knockdown, Western blot, invasion/migration assays","journal":"Carcinogenesis","confidence":"Medium","confidence_rationale":"Tier 2–3 — ChIP evidence for direct binding + functional downstream readouts in a single study","pmids":["21880579"],"is_preprint":false},{"year":2004,"finding":"Angiotensin II stimulates Pax-2 gene expression in rat proximal tubular cells via the AT2 receptor and the JAK2/STAT signaling pathway; cells lacking Pax-2 are prone to apoptosis rather than proliferation, and stable sense Pax-2 increases proliferation while antisense Pax-2 reduces it.","method":"Western blot, RT-PCR, pharmacological inhibitors (PD123319, AG490, genistein), stable transfection, TUNEL, BrdU assays","journal":"Kidney International","confidence":"Medium","confidence_rationale":"Tier 2 — pharmacological pathway dissection + stable transfection with functional readouts in a single study","pmids":["15569307"],"is_preprint":false},{"year":2010,"finding":"Pax2 controls inner ear placode morphogenesis by regulating apical localization of N-cadherin and N-CAM: in the absence of Pax2, otic progenitors lose apically localized N-cadherin and N-CAM and fail to elongate, while misexpression of Pax2 leads to ectopic activation of both adhesion molecules. Pax2 regulates cell shape independently from otic cell identity.","method":"Loss-of-function (morpholino/knockout), gain-of-function (misexpression), immunostaining for N-cadherin and N-CAM in chick otic placode","journal":"Developmental Biology","confidence":"Medium","confidence_rationale":"Tier 2 — reciprocal gain/loss-of-function with molecular target identification","pmids":["20643116"],"is_preprint":false},{"year":2006,"finding":"Pax2 overexpression in the optic nerve is sufficient to block neuronal differentiation and promote astroglial development; Pax2 expression in optic nerve progenitors is maintained by a Sonic hedgehog–FGF signaling cascade.","method":"Electroporation-based overexpression in chick optic nerve/neural tube, in vitro signaling pathway inhibition, loss-of-function explant cultures","journal":"Developmental Biology","confidence":"Medium","confidence_rationale":"Tier 2 — gain-of-function with defined cell fate readout; signaling pathway dissected by inhibitors","pmids":["17173889"],"is_preprint":false},{"year":2009,"finding":"BMP7 and SHH activate Pax2 expression in mouse retinal astrocyte precursors by relieving repression by TLX; BMP and SHH pathway members interact with TLX to derepress Pax2 expression.","method":"In vitro retinal astrocyte precursor cultures, BMP7/SHH treatment, pathway inhibition, co-immunoprecipitation of pathway components with TLX","journal":"Developmental Biology","confidence":"Medium","confidence_rationale":"Tier 2–3 — in vitro pathway analysis with interaction data; mechanism partially characterized","pmids":["19505455"],"is_preprint":false},{"year":2006,"finding":"In C. elegans, Pax2/5/8-related proteins (egl-38 and pax-2) promote cell survival by acting as transcriptional regulators of ced-9, the C. elegans bcl-2 gene, as shown by genetic and molecular experiments.","method":"Genetic epistasis analysis, molecular/expression studies in C. elegans","journal":"Development","confidence":"Medium","confidence_rationale":"Tier 2 — genetic epistasis with molecular readout in a well-established model; ortholog with conserved function","pmids":["17021039"],"is_preprint":false},{"year":2015,"finding":"PAX2 directly binds to two sites in the IL-5 promoter and stimulates IL-5 promoter activity and expression in esophageal cancer cells, as confirmed by ChIP; IL-5 is identified as a PAX2 effector mediating tumor metastasis.","method":"ChIP, luciferase reporter assay, mRNA microarray, shRNA knockdown","journal":"Cellular Physiology and Biochemistry","confidence":"Medium","confidence_rationale":"Tier 2–3 — ChIP + reporter assay confirming direct binding and transcriptional activation","pmids":["25613757"],"is_preprint":false},{"year":2017,"finding":"A small molecule (EG1) identified by virtual screening of a Pax2 paired domain homology model inhibits Pax2-DNA binding with Kd 1.35–1.5 µM, blocks Pax2-mediated transactivation in cell-based assays, inhibits embryonic kidney development in a Pax2-dependent manner, and reduces proliferation of Pax2-positive cancer cell lines.","method":"Virtual screen on Pax2 paired domain homology model, in vitro DNA binding assay, cell-based transactivation assay, ex vivo kidney culture","journal":"ACS Chemical Biology","confidence":"Medium","confidence_rationale":"Tier 1–2 — structural model + in vitro binding + cell-based assay + ex vivo functional test","pmids":["28094913"],"is_preprint":false},{"year":2020,"finding":"Pax2 and Pax8 regulate urine concentration in the adult kidney by controlling expression of urea transporters (Slc14a2) and aquaporins in the inner and outer medulla; Pax8 expression is induced by high-salt in collecting duct cells and activates Slc14a2 by recruiting a histone methyltransferase complex to the promoter. Mice with induced double deletion develop severe polyuria.","method":"Inducible conditional KO of Pax2/Pax8 in adult mice, gene expression profiling, ChIP for histone methyltransferase recruitment","journal":"Journal of the American Society of Nephrology","confidence":"Medium","confidence_rationale":"Tier 2 — in vivo inducible KO with defined molecular targets; mechanistic confirmation by ChIP","pmids":["32381599"],"is_preprint":false},{"year":2010,"finding":"PAX2 missense mutations in the paired domain (e.g., p.T74A) reduce Pax2 transactivation activity and protein stability without affecting nuclear localization, steady-state mRNA, or DNA consensus binding in vitro, indicating that PAX2/Pax2 disease alleles can act as hypomorphic alleles.","method":"Reporter assay (transactivation), in vitro DNA binding assay, protein stability analysis, mouse knock-in model","journal":"PLoS Genetics","confidence":"Medium","confidence_rationale":"Tier 1–2 — functional mutagenesis + in vivo mouse model; mechanistic dissection of pathogenic variants","pmids":["20221250"],"is_preprint":false},{"year":2014,"finding":"FSGS-associated PAX2 mutations perturb PAX2 function by affecting proper DNA binding and transactivation activity, or by altering interaction of PAX2 with repressor proteins, resulting in enhanced repressor activity; mutations can cause disease through haploinsufficiency and dominant negative effects.","method":"In vitro functional studies (DNA binding, transactivation assays), in silico structural modeling","journal":"Journal of the American Society of Nephrology","confidence":"Medium","confidence_rationale":"Tier 1–3 — in vitro functional assays with structural support, single study","pmids":["24676634"],"is_preprint":false},{"year":1998,"finding":"In HEK293 cells stably expressing PAX2, PAX2 increases WT1 and E-cadherin expression (~2-fold and ~7-fold respectively) and strongly suppresses vimentin expression (to ~8% of control), mimicking aspects of mesenchymal-to-epithelial transition during nephrogenesis.","method":"Stable tetracycline-regulatable transfection in HEK293 cells, RT-PCR, Western blot","journal":"Biochimica et Biophysica Acta","confidence":"Medium","confidence_rationale":"Tier 2–3 — stable expression system with multiple gene expression readouts; single lab","pmids":["9459485"],"is_preprint":false},{"year":2002,"finding":"Pax2 expression is upregulated in tubular cells during renal regeneration after ischemia; activin A signaling (via follistatin-sensitive pathway) modulates the growth of Pax2-positive proliferating tubular progenitor-like cells, and activin A reduces Pax2 expression in cultured metanephroi and in LLC-PK1 cells.","method":"Immunostaining in ischemic rat kidneys, follistatin/activin A administration in vivo, metanephros culture, dominant-negative receptor transfection in LLC-PK1 cells","journal":"Journal of the American Society of Nephrology","confidence":"Medium","confidence_rationale":"Tier 2–3 — in vivo and in vitro systems with genetic manipulation; mechanistic link established between activin A signaling and Pax2 expression","pmids":["12444203"],"is_preprint":false},{"year":2012,"finding":"Pax2 suppression in the posterior placodal area (PPA) reduces cell proliferation, and both over-expression and repression of Pax2 produce smaller otocysts and reduced epibranchial placodes, indicating Pax2 functions in maintaining cell cycle proliferation during PPA maintenance.","method":"Gain-of-function and loss-of-function (electroporation/morpholino) in chick embryos, cell cycle analysis (BrdU, pH3)","journal":"Developmental Dynamics","confidence":"Medium","confidence_rationale":"Tier 2 — reciprocal gain/loss-of-function with cell cycle readout","pmids":["22972769"],"is_preprint":false},{"year":2005,"finding":"Tamoxifen-mediated activation of PAX2 in endometrial carcinomas (but not normal endometrium) is associated with cancer-linked hypomethylation of the PAX2 promoter; PAX2 is crucially involved in cell proliferation and carcinogenesis in the endometrium.","method":"Promoter methylation analysis, reporter assays, siRNA knockdown in endometrial carcinoma cell lines","journal":"Nature","confidence":"Medium","confidence_rationale":"Tier 2 — epigenetic mechanism established with functional cell proliferation readout; single study","pmids":["16355216"],"is_preprint":false},{"year":2020,"finding":"ASH2L associates with ERα and is recruited to cis-regulatory elements of PAX2, altering histone H3K4me3 and H3K27me3 levels to enhance ERα-mediated transactivation of PAX2 in endometrial cancer cells.","method":"ChIP-seq, co-IP (ASH2L–ERα), siRNA knockdown, histone modification analysis","journal":"Cancer Science","confidence":"Medium","confidence_rationale":"Tier 2 — ChIP-seq + co-IP + histone modification readout in a single study","pmids":["32279431"],"is_preprint":false}],"current_model":"PAX2 is a paired-domain transcription factor that binds specific DNA sequences through its paired domain and acts as either a transcriptional activator or repressor depending on cofactor context: it activates target genes (including WNT4, WNT5A, NAIP, ADAM10, Brn1, IL-5) by recruiting the PTIP adaptor and histone methyltransferase complexes, while it is switched to a repressor by Groucho/TLE proteins whose recruitment is facilitated by the phosphatase PPM1B dephosphorylating the Pax2 activation domain; JNK-mediated phosphorylation of the activation domain promotes transactivation, and this is counteracted by Grg4; in development, Pax2 is essential for nephric lineage specification (together with Pax8), renal mesenchymal-to-epithelial transition, optic fissure closure, and cochlear morphogenesis, while its expression is regulated upstream by WT1 (repression), p53, TLX, BMP7/SHH (via TLX), and angiotensin II/AT2R/JAK2-STAT signaling, and its protein stability is negatively regulated post-translationally by PHD3-mediated targeting for proteasomal destruction."},"narrative":{"teleology":[{"year":1993,"claim":"Deregulated Pax2 expression in transgenic mice established that PAX2 must be tightly regulated for normal kidney epithelial differentiation, revealing it as a dosage-sensitive developmental regulator rather than simply required for kidney induction.","evidence":"Transgenic mice with constitutive Pax2 expression showing nephrotic syndrome-like histology","pmids":["8383297"],"confidence":"High","gaps":["Target genes mediating the gain-of-function phenotype were unknown","Whether the effect was cell-autonomous in specific nephron segments was not determined"]},{"year":1995,"claim":"The discovery that WT1 directly represses Pax2 transcription via binding in the 5' leader established the first upstream regulator of PAX2 and linked PAX2 silencing to podocyte differentiation.","evidence":"DNase I footprinting of WT1 on Pax2 promoter and CAT reporter assays in co-transfection experiments","pmids":["7720589"],"confidence":"High","gaps":["Whether WT1 repression is sufficient for Pax2 downregulation in vivo was not tested by WT1 conditional deletion at this point"]},{"year":1996,"claim":"Pax2 knockout mice revealed its indispensable role in optic fissure closure, cochlear development, and optic chiasm formation, defining the scope of PAX2 developmental requirements beyond kidney.","evidence":"Pax2-null mice analyzed by paint-fill, histology, and gene expression","pmids":["8951055"],"confidence":"High","gaps":["Downstream target genes in eye and ear were not identified","Cell-autonomous versus non-autonomous effects were not resolved"]},{"year":1996,"claim":"Mapping of the PAX2 transactivation domain (aa 279–373) and identification of the octapeptide as an intrinsic repression domain established the modular architecture governing PAX2's dual activator/repressor function.","evidence":"GAL4 fusion deletion mapping with reporter assays in tissue culture","pmids":["8702876"],"confidence":"High","gaps":["Cofactors mediating octapeptide-dependent repression were not yet identified","Post-translational modifications of the activation domain were unknown"]},{"year":2000,"claim":"Identification of PTIP as a direct binding partner of the PAX2 activation domain linked PAX2 to active chromatin and histone-modifying machinery, providing the first mechanistic explanation for how PAX2 activates transcription.","evidence":"Yeast two-hybrid, in vitro pulldown, and co-localization in nuclear matrix fractions","pmids":["10908331"],"confidence":"High","gaps":["The specific histone modifications deposited via PTIP at PAX2 target genes were not determined","Whether PTIP is required for all PAX2-dependent activation was untested"]},{"year":2002,"claim":"Pax2/Pax8 double-knockout and Pax2 misexpression experiments demonstrated that Pax2 (with Pax8) is the earliest specification factor for the entire nephric lineage, resolving its position at the top of the kidney developmental hierarchy.","evidence":"Double-mutant mice lacking all nephric structures; retroviral Pax2 misexpression inducing ectopic nephric tissue in chick","pmids":["12435636"],"confidence":"High","gaps":["Direct transcriptional targets mediating nephric specification (beyond Lim1 and c-Ret) were not identified","Relative contributions of Pax2 versus Pax8 were not fully resolved"]},{"year":2003,"claim":"The finding that Groucho/Grg4 suppresses PAX2 transactivation by specifically blocking JNK-mediated phosphorylation of the activation domain — independently of histone deacetylation — revealed the molecular switch converting PAX2 from activator to repressor.","evidence":"Co-IP, in vitro kinase assay, reporter assays with HDAC inhibitors and mutagenesis","pmids":["14532124"],"confidence":"High","gaps":["The JNK phosphorylation sites on PAX2 were not mapped","Whether Grg4 recruitment occurs at all PAX2 target loci was unknown"]},{"year":2005,"claim":"Direct PAX2 binding to and activation of the WNT4 promoter connected PAX2 to the mesenchymal-to-epithelial transition signal, identifying the first direct downstream effector linking PAX2 to nephron induction.","evidence":"EMSA, reporter assays, and reduced Wnt4 mRNA in Pax2 heterozygous kidneys","pmids":["16368682"],"confidence":"High","gaps":["Whether PAX2 is sufficient for WNT4 activation in the absence of cofactors was not established","Other PAX2 targets required for MET were not mapped"]},{"year":2008,"claim":"PAX2 was shown to mediate ER-dependent ERBB2 repression in breast cancer, with PAX2 and AIB-1/SRC-3 competing at the ERBB2 locus, establishing PAX2 as a determinant of tamoxifen response and expanding its role beyond development.","evidence":"ChIP, co-IP, reporter assays, and siRNA knockdown in human breast cancer cell lines","pmids":["19005469"],"confidence":"High","gaps":["Structural basis of PAX2–AIB-1 competition at the ERBB2 element was not resolved","Whether PAX2 represses ERBB2 in normal breast epithelium was unknown"]},{"year":2010,"claim":"Characterization of a PAX2 disease missense mutation (T74A) as a hypomorphic allele with reduced transactivation and protein stability — without loss of DNA binding — revealed that PAX2-associated renal disease can arise from quantitative functional impairment rather than complete loss of DNA recognition.","evidence":"Reporter assays, in vitro binding, protein stability analysis, and mouse knock-in model","pmids":["20221250"],"confidence":"Medium","gaps":["The mechanism by which T74A reduces protein stability was not determined","Whether all renal-coloboma mutations act as hypomorphs was not systematically tested"]},{"year":2015,"claim":"Identification of PPM1B as the phosphatase within the Groucho repressor complex that dephosphorylates the PAX2 activation domain and displaces PTIP completed the activator-to-repressor switch mechanism, showing that H3K4 methylation status at PAX2 targets is dynamically controlled by the balance between JNK phosphorylation and PPM1B dephosphorylation.","evidence":"Co-IP, ChIP, reporter assays, siRNA knockdown of PPM1B, histone methylation analysis","pmids":["25631048"],"confidence":"High","gaps":["Whether PPM1B activity is itself regulated in a tissue-specific manner was not explored","The full set of loci where the PTIP/PPM1B switch operates genome-wide was not mapped"]},{"year":2020,"claim":"Inducible Pax2/Pax8 deletion in adult kidney demonstrated a maintained role for these factors in regulating urine concentration through urea transporter and aquaporin expression, extending PAX2 function from developmental patterning to adult homeostasis.","evidence":"Conditional double KO in adult mice with gene expression profiling and ChIP for histone methyltransferase recruitment","pmids":["32381599"],"confidence":"Medium","gaps":["Individual contributions of Pax2 versus Pax8 to adult collecting duct gene regulation were not separated","Whether PAX2 directly binds Slc14a2 regulatory elements (as opposed to Pax8) was not resolved"]},{"year":null,"claim":"A genome-wide map of direct PAX2 binding sites and the structural basis for its context-dependent switch between activation and repression remain to be determined.","evidence":"","pmids":[],"confidence":"Low","gaps":["No genome-wide ChIP-seq for PAX2 across developmental stages has been reported in the timeline","No crystal structure of PAX2 paired domain bound to a physiological target site is described","How tissue-specific cofactor availability determines activator versus repressor output at individual loci is unresolved"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0003677","term_label":"DNA binding","supporting_discovery_ids":[5,6,9,17,27]},{"term_id":"GO:0140110","term_label":"transcription regulator activity","supporting_discovery_ids":[3,5,7,8,9,10,11,12,19,26]}],"localization":[{"term_id":"GO:0005634","term_label":"nucleus","supporting_discovery_ids":[6,17]}],"pathway":[{"term_id":"R-HSA-1266738","term_label":"Developmental Biology","supporting_discovery_ids":[0,1,2,22,23]},{"term_id":"R-HSA-162582","term_label":"Signal Transduction","supporting_discovery_ids":[9,19,21]},{"term_id":"R-HSA-4839726","term_label":"Chromatin organization","supporting_discovery_ids":[6,8]}],"complexes":[],"partners":["PTIP","GRG4","PPM1B","WT1","PHD3","AIB1","TLX","ASH2L"],"other_free_text":[]},"mechanistic_narrative":"PAX2 is a paired-domain transcription factor that plays essential roles in kidney, eye, ear, and midbrain-hindbrain boundary development by controlling nephric lineage specification, mesenchymal-to-epithelial transition, optic fissure closure, and cochlear morphogenesis [PMID:8951055, PMID:12435636, PMID:8383297]. PAX2 binds DNA through its paired domain and activates transcription of target genes including WNT4, WNT5A, NAIP, Brn1, ADAM10, and IL-5 via its C-terminal activation domain (residues 279–373), which recruits the BRCT-domain adaptor PTIP to engage histone methyltransferase complexes; JNK-mediated phosphorylation of this domain promotes transactivation [PMID:8702876, PMID:10908331, PMID:16368682, PMID:14532124]. PAX2 is converted from an activator to a repressor by Groucho/TLE family corepressors, which recruit the phosphatase PPM1B to dephosphorylate the activation domain, displacing PTIP and inhibiting H3K4 methylation at target loci [PMID:14532124, PMID:25631048]. Loss-of-function mutations in PAX2 cause renal-coloboma syndrome and focal segmental glomerulosclerosis through haploinsufficiency or dominant-negative impairment of DNA binding and transactivation [PMID:20221250, PMID:24676634]."},"prefetch_data":{"uniprot":{"accession":"Q02962","full_name":"Paired box protein Pax-2","aliases":[],"length_aa":417,"mass_kda":44.7,"function":"Transcription factor that may have a role in kidney cell differentiation (PubMed:24676634). Has a critical role in the development of the urogenital tract, the eyes, and the CNS","subcellular_location":"Nucleus","url":"https://www.uniprot.org/uniprotkb/Q02962/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/PAX2","classification":"Not Classified","n_dependent_lines":3,"n_total_lines":1208,"dependency_fraction":0.0024834437086092716},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[],"url":"https://opencell.sf.czbiohub.org/search/PAX2","total_profiled":1310},"omim":[{"mim_id":"620164","title":"ZINC FINGER- AND BTB DOMAIN-CONTAINING PROTEIN 26; ZBTB26","url":"https://www.omim.org/entry/620164"},{"mim_id":"616741","title":"PR DOMAIN-CONTAINING PROTEIN 13; PRDM13","url":"https://www.omim.org/entry/616741"},{"mim_id":"616002","title":"FOCAL SEGMENTAL GLOMERULOSCLEROSIS 7; FSGS7","url":"https://www.omim.org/entry/616002"},{"mim_id":"611608","title":"MICRO RNA 183; MIR183","url":"https://www.omim.org/entry/611608"},{"mim_id":"611607","title":"MICRO RNA 182; MIR182","url":"https://www.omim.org/entry/611607"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Supported","locations":[{"location":"Nucleoplasm","reliability":"Supported"}],"tissue_specificity":"Group enriched","tissue_distribution":"Detected in some","driving_tissues":[{"tissue":"epididymis","ntpm":28.0},{"tissue":"kidney","ntpm":94.2}],"url":"https://www.proteinatlas.org/search/PAX2"},"hgnc":{"alias_symbol":["PAX-2"],"prev_symbol":[]},"alphafold":{"accession":"Q02962","domains":[{"cath_id":"1.10.10.10","chopping":"17-74","consensus_level":"high","plddt":95.4114,"start":17,"end":74},{"cath_id":"1.10.10.10","chopping":"92-140","consensus_level":"high","plddt":93.4849,"start":92,"end":140}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q02962","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q02962-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q02962-F1-predicted_aligned_error_v6.png","plddt_mean":60.94},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=PAX2","jax_strain_url":"https://www.jax.org/strain/search?query=PAX2"},"sequence":{"accession":"Q02962","fasta_url":"https://rest.uniprot.org/uniprotkb/Q02962.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q02962/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q02962"}},"corpus_meta":[{"pmid":"8951055","id":"PMC_8951055","title":"Pax2 contributes to inner ear patterning and optic nerve trajectory.","date":"1996","source":"Development (Cambridge, England)","url":"https://pubmed.ncbi.nlm.nih.gov/8951055","citation_count":492,"is_preprint":false},{"pmid":"12435636","id":"PMC_12435636","title":"Nephric lineage specification by Pax2 and Pax8.","date":"2002","source":"Genes & development","url":"https://pubmed.ncbi.nlm.nih.gov/12435636","citation_count":410,"is_preprint":false},{"pmid":"1977575","id":"PMC_1977575","title":"Spatially and temporally restricted expression of Pax2 during murine neurogenesis.","date":"1990","source":"Development (Cambridge, England)","url":"https://pubmed.ncbi.nlm.nih.gov/1977575","citation_count":371,"is_preprint":false},{"pmid":"8383297","id":"PMC_8383297","title":"Deregulation of Pax-2 expression in transgenic mice generates severe kidney abnormalities.","date":"1993","source":"Nature","url":"https://pubmed.ncbi.nlm.nih.gov/8383297","citation_count":260,"is_preprint":false},{"pmid":"19005469","id":"PMC_19005469","title":"Regulation of ERBB2 by oestrogen receptor-PAX2 determines response to tamoxifen.","date":"2008","source":"Nature","url":"https://pubmed.ncbi.nlm.nih.gov/19005469","citation_count":247,"is_preprint":false},{"pmid":"15083520","id":"PMC_15083520","title":"Generation of Pax2-Cre mice by modification of a Pax2 bacterial artificial chromosome.","date":"2004","source":"Genesis (New York, N.Y. : 2000)","url":"https://pubmed.ncbi.nlm.nih.gov/15083520","citation_count":246,"is_preprint":false},{"pmid":"7720589","id":"PMC_7720589","title":"Repression of Pax-2 by WT1 during normal kidney development.","date":"1995","source":"Development (Cambridge, England)","url":"https://pubmed.ncbi.nlm.nih.gov/7720589","citation_count":233,"is_preprint":false},{"pmid":"16355216","id":"PMC_16355216","title":"Hypomethylation-linked activation of PAX2 mediates tamoxifen-stimulated endometrial carcinogenesis.","date":"2005","source":"Nature","url":"https://pubmed.ncbi.nlm.nih.gov/16355216","citation_count":218,"is_preprint":false},{"pmid":"17314325","id":"PMC_17314325","title":"Pax2 and pax8 regulate branching morphogenesis and nephron differentiation in the developing kidney.","date":"2007","source":"Journal of the American Society of Nephrology : JASN","url":"https://pubmed.ncbi.nlm.nih.gov/17314325","citation_count":181,"is_preprint":false},{"pmid":"9159136","id":"PMC_9159136","title":"Cooperation of Pax2 and Pax5 in midbrain and cerebellum development.","date":"1997","source":"Proceedings of the National Academy of Sciences of the United States of America","url":"https://pubmed.ncbi.nlm.nih.gov/9159136","citation_count":143,"is_preprint":false},{"pmid":"15242798","id":"PMC_15242798","title":"The role of Pax2 in mouse inner ear development.","date":"2004","source":"Developmental biology","url":"https://pubmed.ncbi.nlm.nih.gov/15242798","citation_count":142,"is_preprint":false},{"pmid":"20727173","id":"PMC_20727173","title":"Pax2 and Pax8 cooperate in mouse inner ear morphogenesis and innervation.","date":"2010","source":"BMC developmental biology","url":"https://pubmed.ncbi.nlm.nih.gov/20727173","citation_count":127,"is_preprint":false},{"pmid":"11793341","id":"PMC_11793341","title":"Expression of the transcription factors GATA3 and Pax2 during development of the mammalian inner ear.","date":"2002","source":"The Journal of comparative neurology","url":"https://pubmed.ncbi.nlm.nih.gov/11793341","citation_count":124,"is_preprint":false},{"pmid":"9486533","id":"PMC_9486533","title":"Xenopus Pax-2 displays multiple splice forms during embryogenesis and pronephric kidney development.","date":"1997","source":"Mechanisms of development","url":"https://pubmed.ncbi.nlm.nih.gov/9486533","citation_count":121,"is_preprint":false},{"pmid":"10466411","id":"PMC_10466411","title":"Renal-coloboma syndrome: a multi-system developmental disorder caused by PAX2 mutations.","date":"1999","source":"Clinical genetics","url":"https://pubmed.ncbi.nlm.nih.gov/10466411","citation_count":120,"is_preprint":false},{"pmid":"20597068","id":"PMC_20597068","title":"Secretory cell outgrowth, PAX2 and serous carcinogenesis in the Fallopian tube.","date":"2010","source":"The Journal of pathology","url":"https://pubmed.ncbi.nlm.nih.gov/20597068","citation_count":119,"is_preprint":false},{"pmid":"10706625","id":"PMC_10706625","title":"The orphan nuclear receptor Tlx regulates Pax2 and is essential for vision.","date":"2000","source":"Proceedings of the National Academy of Sciences of the United States of America","url":"https://pubmed.ncbi.nlm.nih.gov/10706625","citation_count":107,"is_preprint":false},{"pmid":"20562848","id":"PMC_20562848","title":"High-grade fimbrial-ovarian carcinomas are unified by altered p53, PTEN and PAX2 expression.","date":"2010","source":"Modern pathology : an official journal of the United States and Canadian Academy of Pathology, Inc","url":"https://pubmed.ncbi.nlm.nih.gov/20562848","citation_count":100,"is_preprint":false},{"pmid":"10535325","id":"PMC_10535325","title":"Pax2 in development and renal disease.","date":"1999","source":"The International journal of developmental biology","url":"https://pubmed.ncbi.nlm.nih.gov/10535325","citation_count":95,"is_preprint":false},{"pmid":"24676634","id":"PMC_24676634","title":"Mutations in PAX2 associate with adult-onset FSGS.","date":"2014","source":"Journal of the American Society of Nephrology : JASN","url":"https://pubmed.ncbi.nlm.nih.gov/24676634","citation_count":94,"is_preprint":false},{"pmid":"21380624","id":"PMC_21380624","title":"HNF1B and PAX2 mutations are a common cause of renal hypodysplasia in the CKiD cohort.","date":"2011","source":"Pediatric nephrology (Berlin, Germany)","url":"https://pubmed.ncbi.nlm.nih.gov/21380624","citation_count":93,"is_preprint":false},{"pmid":"10694420","id":"PMC_10694420","title":"Reduced Pax2 gene dosage increases apoptosis and slows the progression of renal cystic disease.","date":"2000","source":"Developmental biology","url":"https://pubmed.ncbi.nlm.nih.gov/10694420","citation_count":92,"is_preprint":false},{"pmid":"14568547","id":"PMC_14568547","title":"Zebrafish hhex, nk2.1a, and pax2.1 regulate thyroid growth and differentiation downstream of Nodal-dependent transcription factors.","date":"2003","source":"Developmental biology","url":"https://pubmed.ncbi.nlm.nih.gov/14568547","citation_count":89,"is_preprint":false},{"pmid":"11807024","id":"PMC_11807024","title":"The activation and maintenance of Pax2 expression at the mid-hindbrain boundary is controlled by separate enhancers.","date":"2002","source":"Development (Cambridge, England)","url":"https://pubmed.ncbi.nlm.nih.gov/11807024","citation_count":85,"is_preprint":false},{"pmid":"18634777","id":"PMC_18634777","title":"Ptf1a, Lbx1 and Pax2 coordinate glycinergic and peptidergic transmitter phenotypes in dorsal spinal inhibitory neurons.","date":"2008","source":"Developmental biology","url":"https://pubmed.ncbi.nlm.nih.gov/18634777","citation_count":82,"is_preprint":false},{"pmid":"19525924","id":"PMC_19525924","title":"PAX2 expression in low malignant potential ovarian tumors and low-grade ovarian serous carcinomas.","date":"2009","source":"Modern pathology : an official journal of the United States and Canadian Academy of Pathology, Inc","url":"https://pubmed.ncbi.nlm.nih.gov/19525924","citation_count":78,"is_preprint":false},{"pmid":"31553714","id":"PMC_31553714","title":"Exosomal MiR-744 Inhibits Proliferation and Sorafenib Chemoresistance in Hepatocellular Carcinoma by Targeting PAX2.","date":"2019","source":"Medical science monitor : international medical journal of experimental and clinical research","url":"https://pubmed.ncbi.nlm.nih.gov/31553714","citation_count":78,"is_preprint":false},{"pmid":"12444203","id":"PMC_12444203","title":"Involvement of Pax-2 in the action of activin A on tubular cell regeneration.","date":"2002","source":"Journal of the American Society of Nephrology : JASN","url":"https://pubmed.ncbi.nlm.nih.gov/12444203","citation_count":73,"is_preprint":false},{"pmid":"14532124","id":"PMC_14532124","title":"Groucho suppresses Pax2 transactivation by inhibition of JNK-mediated phosphorylation.","date":"2003","source":"The EMBO journal","url":"https://pubmed.ncbi.nlm.nih.gov/14532124","citation_count":72,"is_preprint":false},{"pmid":"10908331","id":"PMC_10908331","title":"PTIP, a novel BRCT domain-containing protein interacts with Pax2 and is associated with active chromatin.","date":"2000","source":"Nucleic acids research","url":"https://pubmed.ncbi.nlm.nih.gov/10908331","citation_count":70,"is_preprint":false},{"pmid":"11093271","id":"PMC_11093271","title":"PAX2 mutations in renal-coloboma syndrome: mutational hotspot and germline mosaicism.","date":"2000","source":"European journal of human genetics : EJHG","url":"https://pubmed.ncbi.nlm.nih.gov/11093271","citation_count":66,"is_preprint":false},{"pmid":"10906468","id":"PMC_10906468","title":"Pax2, Otx2, Gbx2 and Fgf8 expression in early otic vesicle development.","date":"2000","source":"Mechanisms of development","url":"https://pubmed.ncbi.nlm.nih.gov/10906468","citation_count":63,"is_preprint":false},{"pmid":"19951611","id":"PMC_19951611","title":"Expression of CD133, PAX2, ESA, and GPR30 in invasive ductal breast carcinomas.","date":"2009","source":"Chinese medical journal","url":"https://pubmed.ncbi.nlm.nih.gov/19951611","citation_count":63,"is_preprint":false},{"pmid":"11850818","id":"PMC_11850818","title":"Expression of the PAX2 oncogene in human breast cancer and its role in progesterone-dependent mammary growth.","date":"2002","source":"Oncogene","url":"https://pubmed.ncbi.nlm.nih.gov/11850818","citation_count":62,"is_preprint":false},{"pmid":"8702876","id":"PMC_8702876","title":"Mapping of Pax-2 transcription activation domains.","date":"1996","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/8702876","citation_count":61,"is_preprint":false},{"pmid":"10662641","id":"PMC_10662641","title":"Pax2 and homeodomain proteins cooperatively regulate a 435 bp enhancer of the mouse Pax5 gene at the midbrain-hindbrain boundary.","date":"2000","source":"Development (Cambridge, England)","url":"https://pubmed.ncbi.nlm.nih.gov/10662641","citation_count":61,"is_preprint":false},{"pmid":"7586754","id":"PMC_7586754","title":"Involvement of wnt1 and pax2 in the formation of the midbrain-hindbrain boundary in the zebrafish gastrula.","date":"1995","source":"Developmental genetics","url":"https://pubmed.ncbi.nlm.nih.gov/7586754","citation_count":60,"is_preprint":false},{"pmid":"10446345","id":"PMC_10446345","title":"Roles of Pax-2 in initiation of the chick tectal development.","date":"1999","source":"Brain research. Developmental brain research","url":"https://pubmed.ncbi.nlm.nih.gov/10446345","citation_count":59,"is_preprint":false},{"pmid":"15872005","id":"PMC_15872005","title":"Identification of Pax2-regulated genes by expression profiling of the mid-hindbrain organizer region.","date":"2005","source":"Development (Cambridge, England)","url":"https://pubmed.ncbi.nlm.nih.gov/15872005","citation_count":57,"is_preprint":false},{"pmid":"20643116","id":"PMC_20643116","title":"Pax2 coordinates epithelial morphogenesis and cell fate in the inner ear.","date":"2010","source":"Developmental biology","url":"https://pubmed.ncbi.nlm.nih.gov/20643116","citation_count":55,"is_preprint":false},{"pmid":"16368682","id":"PMC_16368682","title":"PAX2 activates WNT4 expression during mammalian kidney development.","date":"2005","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/16368682","citation_count":55,"is_preprint":false},{"pmid":"8626478","id":"PMC_8626478","title":"Identification of novel Pax-2 binding sites by chromatin precipitation.","date":"1996","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/8626478","citation_count":53,"is_preprint":false},{"pmid":"16049068","id":"PMC_16049068","title":"Multicystic dysplastic kidney and variable phenotype in a family with a novel deletion mutation of PAX2.","date":"2005","source":"Journal of the American Society of Nephrology : JASN","url":"https://pubmed.ncbi.nlm.nih.gov/16049068","citation_count":47,"is_preprint":false},{"pmid":"21880579","id":"PMC_21880579","title":"The transcription factor PAX2 regulates ADAM10 expression in renal cell carcinoma.","date":"2011","source":"Carcinogenesis","url":"https://pubmed.ncbi.nlm.nih.gov/21880579","citation_count":46,"is_preprint":false},{"pmid":"9874314","id":"PMC_9874314","title":"The role of PAX2 in normal and abnormal development of the urinary tract.","date":"1998","source":"Pediatric nephrology (Berlin, Germany)","url":"https://pubmed.ncbi.nlm.nih.gov/9874314","citation_count":44,"is_preprint":false},{"pmid":"30804206","id":"PMC_30804206","title":"Inhibition of soluble epoxide hydrolase attenuates a high-fat diet-mediated renal injury by activating PAX2 and AMPK.","date":"2019","source":"Proceedings of the National Academy of Sciences of the United States of America","url":"https://pubmed.ncbi.nlm.nih.gov/30804206","citation_count":43,"is_preprint":false},{"pmid":"10900085","id":"PMC_10900085","title":"Expression of Pax2 and patterning of the chick inner ear.","date":"1999","source":"Journal of neurocytology","url":"https://pubmed.ncbi.nlm.nih.gov/10900085","citation_count":42,"is_preprint":false},{"pmid":"30511741","id":"PMC_30511741","title":"PAX2 in endometrial carcinogenesis and in differential diagnosis of endometrial hyperplasia: A systematic review and meta-analysis of diagnostic accuracy.","date":"2019","source":"Acta obstetricia et gynecologica Scandinavica","url":"https://pubmed.ncbi.nlm.nih.gov/30511741","citation_count":42,"is_preprint":false},{"pmid":"14627715","id":"PMC_14627715","title":"Role of Pax2 in apoptosis resistance and proinvasive phenotype of Kaposi's sarcoma cells.","date":"2003","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/14627715","citation_count":42,"is_preprint":false},{"pmid":"8827071","id":"PMC_8827071","title":"Pax-2, kidney development, and oncogenesis.","date":"1996","source":"Medical and pediatric oncology","url":"https://pubmed.ncbi.nlm.nih.gov/8827071","citation_count":41,"is_preprint":false},{"pmid":"22138676","id":"PMC_22138676","title":"PAX2 in human kidney malformations and disease.","date":"2011","source":"Pediatric nephrology (Berlin, Germany)","url":"https://pubmed.ncbi.nlm.nih.gov/22138676","citation_count":41,"is_preprint":false},{"pmid":"16436683","id":"PMC_16436683","title":"Expression of Pax2 in human renal tumor-derived endothelial cells sustains apoptosis resistance and angiogenesis.","date":"2006","source":"The American journal of pathology","url":"https://pubmed.ncbi.nlm.nih.gov/16436683","citation_count":41,"is_preprint":false},{"pmid":"22080059","id":"PMC_22080059","title":"PAX2-null secretory cell outgrowths in the oviduct and their relationship to pelvic serous cancer.","date":"2011","source":"Modern pathology : an official journal of the United States and Canadian Academy of Pathology, Inc","url":"https://pubmed.ncbi.nlm.nih.gov/22080059","citation_count":41,"is_preprint":false},{"pmid":"15569307","id":"PMC_15569307","title":"Angiotensin II stimulates Pax-2 in rat kidney proximal tubular cells: impact on proliferation and apoptosis.","date":"2004","source":"Kidney international","url":"https://pubmed.ncbi.nlm.nih.gov/15569307","citation_count":41,"is_preprint":false},{"pmid":"17173889","id":"PMC_17173889","title":"Pax2 regulates neuronal-glial cell fate choice in the embryonic optic nerve.","date":"2006","source":"Developmental biology","url":"https://pubmed.ncbi.nlm.nih.gov/17173889","citation_count":41,"is_preprint":false},{"pmid":"17021039","id":"PMC_17021039","title":"Pax2/5/8 proteins promote cell survival in C. elegans.","date":"2006","source":"Development (Cambridge, England)","url":"https://pubmed.ncbi.nlm.nih.gov/17021039","citation_count":40,"is_preprint":false},{"pmid":"26571382","id":"PMC_26571382","title":"Association of PAX2 and Other Gene Mutations with the Clinical Manifestations of Renal Coloboma Syndrome.","date":"2015","source":"PloS one","url":"https://pubmed.ncbi.nlm.nih.gov/26571382","citation_count":39,"is_preprint":false},{"pmid":"22511595","id":"PMC_22511595","title":"Hnf1b and Pax2 cooperate to control different pathways in kidney and ureter morphogenesis.","date":"2012","source":"Human molecular genetics","url":"https://pubmed.ncbi.nlm.nih.gov/22511595","citation_count":38,"is_preprint":false},{"pmid":"31522607","id":"PMC_31522607","title":"miR-744-5p Inhibits Non-Small Cell Lung Cancer Proliferation and Invasion by Directly Targeting PAX2.","date":"2019","source":"Technology in cancer research & treatment","url":"https://pubmed.ncbi.nlm.nih.gov/31522607","citation_count":38,"is_preprint":false},{"pmid":"16631587","id":"PMC_16631587","title":"An inducible mouse model for PAX2-dependent glomerular disease: insights into a complex pathogenesis.","date":"2006","source":"Current biology : CB","url":"https://pubmed.ncbi.nlm.nih.gov/16631587","citation_count":38,"is_preprint":false},{"pmid":"8482415","id":"PMC_8482415","title":"Aberrant expression of Pax-2 in Danforth's short tail (Sd) mice.","date":"1993","source":"Developmental biology","url":"https://pubmed.ncbi.nlm.nih.gov/8482415","citation_count":37,"is_preprint":false},{"pmid":"31060108","id":"PMC_31060108","title":"Diverse phenotypes in children with PAX2-related disorder.","date":"2019","source":"Molecular genetics & genomic medicine","url":"https://pubmed.ncbi.nlm.nih.gov/31060108","citation_count":37,"is_preprint":false},{"pmid":"34545858","id":"PMC_34545858","title":"Reliable Identification of Endometrial Precancers Through Combined Pax2, β-Catenin, and Pten Immunohistochemistry.","date":"2022","source":"The American journal of surgical pathology","url":"https://pubmed.ncbi.nlm.nih.gov/34545858","citation_count":35,"is_preprint":false},{"pmid":"22984579","id":"PMC_22984579","title":"A p53-Pax2 pathway in kidney development: implications for nephrogenesis.","date":"2012","source":"PloS one","url":"https://pubmed.ncbi.nlm.nih.gov/22984579","citation_count":35,"is_preprint":false},{"pmid":"9459485","id":"PMC_9459485","title":"Effects of PAX2 expression in a human fetal kidney (HEK293) cell line.","date":"1998","source":"Biochimica et biophysica acta","url":"https://pubmed.ncbi.nlm.nih.gov/9459485","citation_count":34,"is_preprint":false},{"pmid":"22617288","id":"PMC_22617288","title":"Evolution of a tissue-specific silencer underlies divergence in the expression of pax2 and pax8 paralogues.","date":"2012","source":"Nature communications","url":"https://pubmed.ncbi.nlm.nih.gov/22617288","citation_count":33,"is_preprint":false},{"pmid":"28094913","id":"PMC_28094913","title":"Inhibition of Pax2 Transcription Activation with a Small Molecule that Targets the DNA Binding Domain.","date":"2017","source":"ACS chemical biology","url":"https://pubmed.ncbi.nlm.nih.gov/28094913","citation_count":33,"is_preprint":false},{"pmid":"19048125","id":"PMC_19048125","title":"WNT5A is regulated by PAX2 and may be involved in blastemal predominant Wilms tumorigenesis.","date":"2008","source":"Neoplasia (New York, N.Y.)","url":"https://pubmed.ncbi.nlm.nih.gov/19048125","citation_count":32,"is_preprint":false},{"pmid":"25446030","id":"PMC_25446030","title":"Pax8 and Pax2 are specifically required at different steps of Xenopus pronephros development.","date":"2014","source":"Developmental biology","url":"https://pubmed.ncbi.nlm.nih.gov/25446030","citation_count":31,"is_preprint":false},{"pmid":"24141260","id":"PMC_24141260","title":"Cotransfection of Pax2 and Math1 promote in situ cochlear hair cell regeneration after neomycin insult.","date":"2013","source":"Scientific reports","url":"https://pubmed.ncbi.nlm.nih.gov/24141260","citation_count":30,"is_preprint":false},{"pmid":"19505455","id":"PMC_19505455","title":"BMP7 and SHH regulate Pax2 in mouse retinal astrocytes by relieving TLX repression.","date":"2009","source":"Developmental biology","url":"https://pubmed.ncbi.nlm.nih.gov/19505455","citation_count":30,"is_preprint":false},{"pmid":"25130537","id":"PMC_25130537","title":"The PAX2-null immunophenotype defines multiple lineages with common expression signatures in benign and neoplastic oviductal epithelium.","date":"2014","source":"The Journal of pathology","url":"https://pubmed.ncbi.nlm.nih.gov/25130537","citation_count":29,"is_preprint":false},{"pmid":"29272992","id":"PMC_29272992","title":"From Otic Induction to Hair Cell Production: Pax2EGFP Cell Line Illuminates Key Stages of Development in Mouse Inner Ear Organoid Model.","date":"2018","source":"Stem cells and development","url":"https://pubmed.ncbi.nlm.nih.gov/29272992","citation_count":28,"is_preprint":false},{"pmid":"7569406","id":"PMC_7569406","title":"Transcription factors in renal development: the WT1 and Pax-2 story.","date":"1995","source":"Seminars in nephrology","url":"https://pubmed.ncbi.nlm.nih.gov/7569406","citation_count":27,"is_preprint":false},{"pmid":"25613757","id":"PMC_25613757","title":"Upregulation of PAX2 promotes the metastasis of esophageal cancer through interleukin-5.","date":"2015","source":"Cellular physiology and biochemistry : international journal of experimental cellular physiology, biochemistry, and pharmacology","url":"https://pubmed.ncbi.nlm.nih.gov/25613757","citation_count":27,"is_preprint":false},{"pmid":"23716939","id":"PMC_23716939","title":"Conditional deletion of the human ortholog gene Dicer1 in Pax2-Cre expression domain impairs orofacial development.","date":"2012","source":"Indian journal of human genetics","url":"https://pubmed.ncbi.nlm.nih.gov/23716939","citation_count":27,"is_preprint":false},{"pmid":"25631048","id":"PMC_25631048","title":"The Groucho-associated phosphatase PPM1B displaces Pax transactivation domain interacting protein (PTIP) to switch the transcription factor Pax2 from a transcriptional activator to a repressor.","date":"2015","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/25631048","citation_count":27,"is_preprint":false},{"pmid":"30096791","id":"PMC_30096791","title":"UnPAXing the Divergent Roles of PAX2 and PAX8 in High-Grade Serous Ovarian Cancer.","date":"2018","source":"Cancers","url":"https://pubmed.ncbi.nlm.nih.gov/30096791","citation_count":26,"is_preprint":false},{"pmid":"9712525","id":"PMC_9712525","title":"Expression of PAX2 gene during human development.","date":"1998","source":"The International journal of developmental biology","url":"https://pubmed.ncbi.nlm.nih.gov/9712525","citation_count":25,"is_preprint":false},{"pmid":"22807381","id":"PMC_22807381","title":"Utility of PAX8 and PAX2 immunohistochemistry in the identification of renal cell carcinoma in diagnostic cytology.","date":"2010","source":"Diagnostic cytopathology","url":"https://pubmed.ncbi.nlm.nih.gov/22807381","citation_count":25,"is_preprint":false},{"pmid":"32381599","id":"PMC_32381599","title":"Pax2 and Pax8 Proteins Regulate Urea Transporters and Aquaporins to Control Urine Concentration in the Adult Kidney.","date":"2020","source":"Journal of the American Society of Nephrology : JASN","url":"https://pubmed.ncbi.nlm.nih.gov/32381599","citation_count":23,"is_preprint":false},{"pmid":"32203253","id":"PMC_32203253","title":"Clinical and genetic variability of PAX2-related disorder in the Japanese population.","date":"2020","source":"Journal of human genetics","url":"https://pubmed.ncbi.nlm.nih.gov/32203253","citation_count":23,"is_preprint":false},{"pmid":"22972769","id":"PMC_22972769","title":"Pax2 modulates proliferation during specification of the otic and epibranchial placodes.","date":"2012","source":"Developmental dynamics : an official publication of the American Association of Anatomists","url":"https://pubmed.ncbi.nlm.nih.gov/22972769","citation_count":23,"is_preprint":false},{"pmid":"34908837","id":"PMC_34908837","title":"The Role of PAX2 in Neurodevelopment and Disease.","date":"2021","source":"Neuropsychiatric disease and treatment","url":"https://pubmed.ncbi.nlm.nih.gov/34908837","citation_count":21,"is_preprint":false},{"pmid":"26373819","id":"PMC_26373819","title":"Divergent Roles of PAX2 in the Etiology and Progression of Ovarian Cancer.","date":"2015","source":"Cancer prevention research (Philadelphia, Pa.)","url":"https://pubmed.ncbi.nlm.nih.gov/26373819","citation_count":21,"is_preprint":false},{"pmid":"9321680","id":"PMC_9321680","title":"Pax-2 in the chiasm.","date":"1997","source":"Cell and tissue research","url":"https://pubmed.ncbi.nlm.nih.gov/9321680","citation_count":21,"is_preprint":false},{"pmid":"32279431","id":"PMC_32279431","title":"ASH2L is involved in promotion of endometrial cancer progression via upregulation of PAX2 transcription.","date":"2020","source":"Cancer science","url":"https://pubmed.ncbi.nlm.nih.gov/32279431","citation_count":21,"is_preprint":false},{"pmid":"23137159","id":"PMC_23137159","title":"Signaling pathways of PAX2 and its role in renal interstitial fibrosis and glomerulosclerosis.","date":"2012","source":"Journal of receptor and signal transduction research","url":"https://pubmed.ncbi.nlm.nih.gov/23137159","citation_count":20,"is_preprint":false},{"pmid":"16735463","id":"PMC_16735463","title":"Neuronal apoptosis inhibitory protein is expressed in developing kidney and is regulated by PAX2.","date":"2006","source":"American journal of physiology. Renal physiology","url":"https://pubmed.ncbi.nlm.nih.gov/16735463","citation_count":20,"is_preprint":false},{"pmid":"23060065","id":"PMC_23060065","title":"Value of PAX2 immunostaining in tumor diagnosis: a review and update.","date":"2012","source":"Advances in anatomic pathology","url":"https://pubmed.ncbi.nlm.nih.gov/23060065","citation_count":19,"is_preprint":false},{"pmid":"25473752","id":"PMC_25473752","title":"Pax2 expression in simultaneously diagnosed WHO and EIN classification systems.","date":"2015","source":"International journal of gynecological pathology : official journal of the International Society of Gynecological Pathologists","url":"https://pubmed.ncbi.nlm.nih.gov/25473752","citation_count":19,"is_preprint":false},{"pmid":"20171202","id":"PMC_20171202","title":"En2, Pax2/5 and Tcf-4 transcription factors cooperate in patterning the Xenopus brain.","date":"2010","source":"Developmental biology","url":"https://pubmed.ncbi.nlm.nih.gov/20171202","citation_count":19,"is_preprint":false},{"pmid":"20221250","id":"PMC_20221250","title":"Papillorenal syndrome-causing missense mutations in PAX2/Pax2 result in hypomorphic alleles in mouse and human.","date":"2010","source":"PLoS genetics","url":"https://pubmed.ncbi.nlm.nih.gov/20221250","citation_count":19,"is_preprint":false},{"pmid":"17020758","id":"PMC_17020758","title":"The Pax2/5/8 gene egl-38 coordinates organogenesis of the C. elegans egg-laying system.","date":"2006","source":"Developmental biology","url":"https://pubmed.ncbi.nlm.nih.gov/17020758","citation_count":19,"is_preprint":false},{"pmid":"35018885","id":"PMC_35018885","title":"Chromatin topology defines estradiol-primed progesterone receptor and PAX2 binding in endometrial cancer cells.","date":"2022","source":"eLife","url":"https://pubmed.ncbi.nlm.nih.gov/35018885","citation_count":18,"is_preprint":false},{"pmid":"28426529","id":"PMC_28426529","title":"Diagnostic Utility of Pax8, Pax2, and NGFR Immunohistochemical Expression in Pediatric Renal Tumors.","date":"2018","source":"Applied immunohistochemistry & molecular morphology : AIMM","url":"https://pubmed.ncbi.nlm.nih.gov/28426529","citation_count":18,"is_preprint":false},{"pmid":"21575608","id":"PMC_21575608","title":"Prolyl hydroxylase domain protein 3 targets Pax2 for destruction.","date":"2011","source":"Biochemical and biophysical research communications","url":"https://pubmed.ncbi.nlm.nih.gov/21575608","citation_count":18,"is_preprint":false},{"pmid":"18056486","id":"PMC_18056486","title":"PAX2 expression by HHV-8-infected endothelial cells induced a proangiogenic and proinvasive phenotype.","date":"2007","source":"Blood","url":"https://pubmed.ncbi.nlm.nih.gov/18056486","citation_count":17,"is_preprint":false},{"pmid":"27991925","id":"PMC_27991925","title":"PAX2 function, regulation and targeting in fallopian tube-derived high-grade serous ovarian cancer.","date":"2016","source":"Oncogene","url":"https://pubmed.ncbi.nlm.nih.gov/27991925","citation_count":17,"is_preprint":false},{"pmid":"12690448","id":"PMC_12690448","title":"Mutations in lozenge and D-Pax2 invoke ectopic patterned cell death in the developing Drosophila eye using distinct mechanisms.","date":"2003","source":"Development genes and evolution","url":"https://pubmed.ncbi.nlm.nih.gov/12690448","citation_count":17,"is_preprint":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":46491,"output_tokens":8061,"usd":0.130194},"stage2":{"model":"claude-opus-4-6","input_tokens":11901,"output_tokens":3086,"usd":0.204983},"total_usd":0.335177,"stage1_batch_id":"msgbatch_012ZiiCUBfB62NCTQd4Bk1Jo","stage2_batch_id":"msgbatch_01Xuqq9aUHoQouS7UVGZNStZ","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 1996,\n      \"finding\": \"Loss-of-function (knockout) of Pax2 in mice results in agenesis of the optic chiasma (ipsilateral optic tracts), coloboma due to failure of optic fissure closure, and agenesis of the cochlea and spiral ganglion, establishing Pax2 as a major regulator of patterning and morphogenesis in the eye and inner ear.\",\n      \"method\": \"Pax2 null mutant mice; paint-fill, gene expression analysis, histology\",\n      \"journal\": \"Development\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — clean KO with defined cellular phenotypes; replicated across multiple subsequent studies\",\n      \"pmids\": [\"8951055\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2002,\n      \"finding\": \"Pax2 and Pax8 together are required to specify the nephric lineage: double-mutant mouse embryos lacking both genes fail to form the pronephros or any subsequent nephric structures, fail to undergo mesenchymal-epithelial transition, and fail to initiate Lim1 and c-Ret expression. Retroviral misexpression of Pax2 alone was sufficient to induce ectopic nephric structures in chick intermediate mesoderm.\",\n      \"method\": \"Pax2/Pax8 double-mutant mice; retroviral misexpression in chick embryos; gene expression analysis\",\n      \"journal\": \"Genes & Development\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — reciprocal gain/loss-of-function with defined molecular and cellular readouts; multiple orthogonal methods\",\n      \"pmids\": [\"12435636\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1993,\n      \"finding\": \"Deregulated (gain-of-function) Pax-2 expression in transgenic mice causes histologically abnormal, dysfunctional renal epithelium with properties similar to congenital nephrotic syndrome, demonstrating that repression of Pax-2 is required for normal kidney development and that persistent Pax-2 expression restricts differentiation potential of renal epithelial cells.\",\n      \"method\": \"Transgenic mice with deregulated Pax-2 expression; histological and functional analysis\",\n      \"journal\": \"Nature\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — clean gain-of-function with defined phenotype, replicated in four independent transgenic embryos/one line\",\n      \"pmids\": [\"8383297\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2008,\n      \"finding\": \"PAX2 acts as a crucial mediator of estrogen receptor (ER)-dependent transcriptional repression of ERBB2/HER-2 in response to tamoxifen in breast cancer cells; PAX2 and the ER co-activator AIB-1/SRC-3 compete for binding and regulation of ERBB2 transcription at a cis-regulatory element within the ERBB2 gene.\",\n      \"method\": \"ChIP, co-IP, reporter assays, siRNA knockdown in human breast cancer cell lines\",\n      \"journal\": \"Nature\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — multiple orthogonal methods (ChIP, co-IP, reporter assay, KD) in a single rigorous study\",\n      \"pmids\": [\"19005469\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1995,\n      \"finding\": \"WT1 protein directly represses Pax-2 transcription by binding to three high-affinity sites in the 5' untranslated Pax-2 leader sequence, as demonstrated by DNase I footprinting and co-transfection/reporter assays; this coincides with down-regulation of Pax-2 in developing podocyte precursors.\",\n      \"method\": \"DNase I footprinting, co-transfection with CAT reporter constructs, immunostaining\",\n      \"journal\": \"Development\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 — in vitro binding assay + functional reporter assay + in vivo expression correlation\",\n      \"pmids\": [\"7720589\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1996,\n      \"finding\": \"Pax-2 transactivation requires amino acids 279–373 in the C-terminus; the conserved octapeptide sequence acts as a repression domain that down-modulates Pax-2 transactivation in heterologous contexts.\",\n      \"method\": \"Deletion/mutation mapping with GAL4 fusion reporter assays in tissue culture cells\",\n      \"journal\": \"Journal of Biological Chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 — domain mapping by mutagenesis with functional reporter assay\",\n      \"pmids\": [\"8702876\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2000,\n      \"finding\": \"PTIP, a novel BRCT domain-containing protein, directly binds to the Pax2 activation domain (but not when the octapeptide repression domain is present), as shown by yeast two-hybrid, in vitro binding, and co-localization in tissue culture nuclei/active chromatin/nuclear matrix fraction, linking Pax2 to active chromatin machinery.\",\n      \"method\": \"Yeast two-hybrid, in vitro pulldown, co-localization in tissue culture cells, nuclear fractionation\",\n      \"journal\": \"Nucleic Acids Research\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — reciprocal binding demonstrated by multiple methods; interaction confirmed in cells\",\n      \"pmids\": [\"10908331\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2003,\n      \"finding\": \"The Groucho/TLE family protein Grg4 interacts with Pax2 to suppress transactivation by specifically inhibiting JNK-mediated phosphorylation of the Pax2 activation domain; this suppression depends on Pax2 binding to its target DNA and is independent of histone deacetylation.\",\n      \"method\": \"Co-IP, in vitro kinase assay, reporter assay, mutagenesis, HDAC inhibitor treatment\",\n      \"journal\": \"EMBO Journal\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 — in vitro kinase assay + co-IP + reporter assay with mutagenesis; multiple orthogonal methods\",\n      \"pmids\": [\"14532124\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"The phosphatase PPM1B is a component of the Groucho4 repressor complex recruited by Pax2 to chromatin; PPM1B dephosphorylates the Pax2 activation domain and displaces the adaptor protein PTIP, thereby inhibiting H3K4 methylation and switching Pax2 from a transcriptional activator to a repressor. Loss of PPM1B prevents Groucho-mediated gene repression.\",\n      \"method\": \"Co-IP, ChIP, reporter assays, siRNA knockdown, histone methylation analysis\",\n      \"journal\": \"Journal of Biological Chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 — multiple orthogonal methods establishing enzymatic mechanism with functional consequence\",\n      \"pmids\": [\"25631048\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2005,\n      \"finding\": \"PAX2 directly activates WNT4 transcription during kidney development by binding to three specific recognition motifs in the WNT4 promoter, as shown by EMSA, co-transfection reporter assays, and reduced Wnt4 mRNA in heterozygous Pax2 mutant mouse kidneys.\",\n      \"method\": \"EMSA, co-transfection reporter assay, RT-PCR in Pax2 heterozygous fetal kidneys\",\n      \"journal\": \"Journal of Biological Chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 — in vitro DNA binding + reporter assay + in vivo genetic confirmation\",\n      \"pmids\": [\"16368682\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2006,\n      \"finding\": \"PAX2 directly binds the neuronal apoptosis inhibitory protein (NAIP) gene promoter and activates NAIP transcription (~7-fold in vitro; 4-fold increase in stably transfected HEK293 cells); Naip mRNA is reduced 50% in heterozygous Pax2 mutant mice, and NAIP suppresses caspase-3/7-mediated apoptosis in collecting duct cells.\",\n      \"method\": \"EMSA, reporter assay, stable transfection, RT-PCR in Pax2 mutant mice, caspase activity assay\",\n      \"journal\": \"American Journal of Physiology: Renal Physiology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 — in vitro DNA binding + reporter + in vivo genetic confirmation with functional apoptosis readout\",\n      \"pmids\": [\"16735463\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2006,\n      \"finding\": \"Inducible podocyte-specific expression of PAX2 in adult mice represses WT1 and consequently reduces nephrin expression, causing end-stage renal failure; recruitment of the Groucho-related protein TLE4 may convert Pax2 into a transcriptional repressor of Wt1.\",\n      \"method\": \"Inducible transgenic mouse model (Cre-lox), immunostaining, gene expression analysis\",\n      \"journal\": \"Current Biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — inducible in vivo model with defined molecular targets and phenotypic readout\",\n      \"pmids\": [\"16631587\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2005,\n      \"finding\": \"Pax2 directly regulates Brn1 (Pou3f3) transcription at the mid-hindbrain boundary via two functional Pax2-binding sites in the Brn1 promoter and upstream regulatory element, as shown by reporter assay; Brn1 in turn is implicated in Fgf8 gene regulation.\",\n      \"method\": \"cDNA microarray with FACS-sorted GFP+ cells from Pax2-/- embryos, lacZ reporter transgene analysis, mutagenesis of Pax2-binding sites, dominant-negative electroporation in chick\",\n      \"journal\": \"Development\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — expression profiling combined with functional reporter assay and mutagenesis\",\n      \"pmids\": [\"15872005\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2000,\n      \"finding\": \"Pax2 and homeodomain proteins cooperatively regulate the Pax5 mhb enhancer through direct binding; mutation of the Pax2/5/8 binding site in the Pax5 enhancer reduces transgene expression at the midbrain-hindbrain boundary, and Pax2 mutant embryos show reduced Pax5 expression specifically in regions dependent on the Pax-binding site.\",\n      \"method\": \"Transgenic reporter assay, site-directed mutagenesis of enhancer binding sites, protein binding assays with mhb-specific extracts, analysis in Pax2 mutant embryos\",\n      \"journal\": \"Development\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 — protein binding + functional mutagenesis + in vivo genetic validation\",\n      \"pmids\": [\"10662641\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2002,\n      \"finding\": \"The activation and maintenance of Pax2 expression at the midbrain-hindbrain boundary are controlled by separate enhancers: an early enhancer (~-3.7 kb, dependent on homeodomain/POU binding sites including Oct3/4) and two late enhancers (~-4.1 kb and ~-2.8 kb); the proximal late enhancer contains a functional Pax2/5/8-binding site mediating auto- and cross-regulatory maintenance.\",\n      \"method\": \"Transgenic reporter analysis, site-directed mutagenesis, BAC transgene deletion analysis, Oct3/4 binding assay\",\n      \"journal\": \"Development\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 — functional enhancer dissection with mutagenesis and in vivo transgenic validation\",\n      \"pmids\": [\"11807024\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"p53 directly occupies chromatin regions of the Pax2 promoter and gene in embryonic kidneys (ChIP-Seq), stimulates Pax2 promoter activity in transfection assays, and p53 knockout mice show reduced Pax2 in nephron progenitors; reducing p53 gene dosage worsens renal hypoplasia in Pax2+/- mice, establishing a p53–Pax2 epistatic relationship in nephrogenesis.\",\n      \"method\": \"ChIP-Seq, transient transfection reporter assay, p53 KO and conditional KO mice, siRNA knockdown in cultured metanephric mesenchyme cells\",\n      \"journal\": \"PLoS One\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 — ChIP-Seq + reporter assay + multiple genetic models with defined phenotypic readout\",\n      \"pmids\": [\"22984579\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2000,\n      \"finding\": \"Tlx (orphan nuclear receptor) directly regulates Pax2 transcription: Tlx binds a conserved site in the Pax2 promoter, Tlx-null mice show reduced Pax2 expression, and Pax2 is identified as a direct transcriptional target of Tlx in retinal development.\",\n      \"method\": \"Tlx targeted knockout mice, P19 neural precursor screen, promoter binding assay, sequence conservation analysis\",\n      \"journal\": \"PNAS\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — in vivo genetic evidence + promoter binding, but functional reporter assay with mutagenesis not detailed\",\n      \"pmids\": [\"10706625\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1996,\n      \"finding\": \"Pax-2 proteins (2A and 2B isoforms) bind DNA through the paired domain with similar specificity; chromatin immunoprecipitation from embryonic neural tube identified novel in vivo Pax-2 binding sites sharing homology with Pax-5 and Pax-2 consensus sequences.\",\n      \"method\": \"Chromatin immunoprecipitation from embryonic neural tube, in vitro DNA binding assays with recombinant Pax-2\",\n      \"journal\": \"Journal of Biological Chemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — ChIP from native tissue + in vitro binding validation; early chromatin precipitation method\",\n      \"pmids\": [\"8626478\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"PHD3 (prolyl hydroxylase domain protein 3) physically binds to Pax2 protein and mediates its proteasomal destruction; inhibition of PHD3 hydroxylase activity increases Pax2 protein but not mRNA levels, identifying PHD3 as a post-translational negative regulator of Pax2 stability.\",\n      \"method\": \"Co-IP, PHD3 inhibitor treatment, Western blot for Pax2 protein vs. mRNA levels\",\n      \"journal\": \"Biochemical and Biophysical Research Communications\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 — single lab, co-IP + inhibitor treatment; proteasomal mechanism inferred but not fully reconstituted\",\n      \"pmids\": [\"21575608\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2008,\n      \"finding\": \"PAX2 directly binds to and transactivates the WNT5A promoter in HEK293 cells, as shown by transactivation assays and EMSA; reduced WNT5A expression in Wilms tumor correlates with blastemal predominance.\",\n      \"method\": \"Chromatin enrichment, ChIP, EMSA, transactivation assay in HEK293 cells\",\n      \"journal\": \"Neoplasia\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — EMSA + functional reporter assay in a single study\",\n      \"pmids\": [\"19048125\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"PAX2 binds to the ADAM10 promoter and regulates ADAM10 protein expression in renal cancer cells; PAX2 silencing leads to reduced ADAM10, reduced L1-CAM shedding, altered EMT markers, and activation of PI3K/Akt pathway via L1-CAM.\",\n      \"method\": \"ChIP (PAX2 binding to ADAM10 promoter), siRNA knockdown, Western blot, invasion/migration assays\",\n      \"journal\": \"Carcinogenesis\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2–3 — ChIP evidence for direct binding + functional downstream readouts in a single study\",\n      \"pmids\": [\"21880579\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2004,\n      \"finding\": \"Angiotensin II stimulates Pax-2 gene expression in rat proximal tubular cells via the AT2 receptor and the JAK2/STAT signaling pathway; cells lacking Pax-2 are prone to apoptosis rather than proliferation, and stable sense Pax-2 increases proliferation while antisense Pax-2 reduces it.\",\n      \"method\": \"Western blot, RT-PCR, pharmacological inhibitors (PD123319, AG490, genistein), stable transfection, TUNEL, BrdU assays\",\n      \"journal\": \"Kidney International\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — pharmacological pathway dissection + stable transfection with functional readouts in a single study\",\n      \"pmids\": [\"15569307\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"Pax2 controls inner ear placode morphogenesis by regulating apical localization of N-cadherin and N-CAM: in the absence of Pax2, otic progenitors lose apically localized N-cadherin and N-CAM and fail to elongate, while misexpression of Pax2 leads to ectopic activation of both adhesion molecules. Pax2 regulates cell shape independently from otic cell identity.\",\n      \"method\": \"Loss-of-function (morpholino/knockout), gain-of-function (misexpression), immunostaining for N-cadherin and N-CAM in chick otic placode\",\n      \"journal\": \"Developmental Biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — reciprocal gain/loss-of-function with molecular target identification\",\n      \"pmids\": [\"20643116\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2006,\n      \"finding\": \"Pax2 overexpression in the optic nerve is sufficient to block neuronal differentiation and promote astroglial development; Pax2 expression in optic nerve progenitors is maintained by a Sonic hedgehog–FGF signaling cascade.\",\n      \"method\": \"Electroporation-based overexpression in chick optic nerve/neural tube, in vitro signaling pathway inhibition, loss-of-function explant cultures\",\n      \"journal\": \"Developmental Biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — gain-of-function with defined cell fate readout; signaling pathway dissected by inhibitors\",\n      \"pmids\": [\"17173889\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"BMP7 and SHH activate Pax2 expression in mouse retinal astrocyte precursors by relieving repression by TLX; BMP and SHH pathway members interact with TLX to derepress Pax2 expression.\",\n      \"method\": \"In vitro retinal astrocyte precursor cultures, BMP7/SHH treatment, pathway inhibition, co-immunoprecipitation of pathway components with TLX\",\n      \"journal\": \"Developmental Biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2–3 — in vitro pathway analysis with interaction data; mechanism partially characterized\",\n      \"pmids\": [\"19505455\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2006,\n      \"finding\": \"In C. elegans, Pax2/5/8-related proteins (egl-38 and pax-2) promote cell survival by acting as transcriptional regulators of ced-9, the C. elegans bcl-2 gene, as shown by genetic and molecular experiments.\",\n      \"method\": \"Genetic epistasis analysis, molecular/expression studies in C. elegans\",\n      \"journal\": \"Development\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — genetic epistasis with molecular readout in a well-established model; ortholog with conserved function\",\n      \"pmids\": [\"17021039\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"PAX2 directly binds to two sites in the IL-5 promoter and stimulates IL-5 promoter activity and expression in esophageal cancer cells, as confirmed by ChIP; IL-5 is identified as a PAX2 effector mediating tumor metastasis.\",\n      \"method\": \"ChIP, luciferase reporter assay, mRNA microarray, shRNA knockdown\",\n      \"journal\": \"Cellular Physiology and Biochemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2–3 — ChIP + reporter assay confirming direct binding and transcriptional activation\",\n      \"pmids\": [\"25613757\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"A small molecule (EG1) identified by virtual screening of a Pax2 paired domain homology model inhibits Pax2-DNA binding with Kd 1.35–1.5 µM, blocks Pax2-mediated transactivation in cell-based assays, inhibits embryonic kidney development in a Pax2-dependent manner, and reduces proliferation of Pax2-positive cancer cell lines.\",\n      \"method\": \"Virtual screen on Pax2 paired domain homology model, in vitro DNA binding assay, cell-based transactivation assay, ex vivo kidney culture\",\n      \"journal\": \"ACS Chemical Biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1–2 — structural model + in vitro binding + cell-based assay + ex vivo functional test\",\n      \"pmids\": [\"28094913\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"Pax2 and Pax8 regulate urine concentration in the adult kidney by controlling expression of urea transporters (Slc14a2) and aquaporins in the inner and outer medulla; Pax8 expression is induced by high-salt in collecting duct cells and activates Slc14a2 by recruiting a histone methyltransferase complex to the promoter. Mice with induced double deletion develop severe polyuria.\",\n      \"method\": \"Inducible conditional KO of Pax2/Pax8 in adult mice, gene expression profiling, ChIP for histone methyltransferase recruitment\",\n      \"journal\": \"Journal of the American Society of Nephrology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — in vivo inducible KO with defined molecular targets; mechanistic confirmation by ChIP\",\n      \"pmids\": [\"32381599\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"PAX2 missense mutations in the paired domain (e.g., p.T74A) reduce Pax2 transactivation activity and protein stability without affecting nuclear localization, steady-state mRNA, or DNA consensus binding in vitro, indicating that PAX2/Pax2 disease alleles can act as hypomorphic alleles.\",\n      \"method\": \"Reporter assay (transactivation), in vitro DNA binding assay, protein stability analysis, mouse knock-in model\",\n      \"journal\": \"PLoS Genetics\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1–2 — functional mutagenesis + in vivo mouse model; mechanistic dissection of pathogenic variants\",\n      \"pmids\": [\"20221250\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"FSGS-associated PAX2 mutations perturb PAX2 function by affecting proper DNA binding and transactivation activity, or by altering interaction of PAX2 with repressor proteins, resulting in enhanced repressor activity; mutations can cause disease through haploinsufficiency and dominant negative effects.\",\n      \"method\": \"In vitro functional studies (DNA binding, transactivation assays), in silico structural modeling\",\n      \"journal\": \"Journal of the American Society of Nephrology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1–3 — in vitro functional assays with structural support, single study\",\n      \"pmids\": [\"24676634\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1998,\n      \"finding\": \"In HEK293 cells stably expressing PAX2, PAX2 increases WT1 and E-cadherin expression (~2-fold and ~7-fold respectively) and strongly suppresses vimentin expression (to ~8% of control), mimicking aspects of mesenchymal-to-epithelial transition during nephrogenesis.\",\n      \"method\": \"Stable tetracycline-regulatable transfection in HEK293 cells, RT-PCR, Western blot\",\n      \"journal\": \"Biochimica et Biophysica Acta\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2–3 — stable expression system with multiple gene expression readouts; single lab\",\n      \"pmids\": [\"9459485\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2002,\n      \"finding\": \"Pax2 expression is upregulated in tubular cells during renal regeneration after ischemia; activin A signaling (via follistatin-sensitive pathway) modulates the growth of Pax2-positive proliferating tubular progenitor-like cells, and activin A reduces Pax2 expression in cultured metanephroi and in LLC-PK1 cells.\",\n      \"method\": \"Immunostaining in ischemic rat kidneys, follistatin/activin A administration in vivo, metanephros culture, dominant-negative receptor transfection in LLC-PK1 cells\",\n      \"journal\": \"Journal of the American Society of Nephrology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2–3 — in vivo and in vitro systems with genetic manipulation; mechanistic link established between activin A signaling and Pax2 expression\",\n      \"pmids\": [\"12444203\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"Pax2 suppression in the posterior placodal area (PPA) reduces cell proliferation, and both over-expression and repression of Pax2 produce smaller otocysts and reduced epibranchial placodes, indicating Pax2 functions in maintaining cell cycle proliferation during PPA maintenance.\",\n      \"method\": \"Gain-of-function and loss-of-function (electroporation/morpholino) in chick embryos, cell cycle analysis (BrdU, pH3)\",\n      \"journal\": \"Developmental Dynamics\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — reciprocal gain/loss-of-function with cell cycle readout\",\n      \"pmids\": [\"22972769\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2005,\n      \"finding\": \"Tamoxifen-mediated activation of PAX2 in endometrial carcinomas (but not normal endometrium) is associated with cancer-linked hypomethylation of the PAX2 promoter; PAX2 is crucially involved in cell proliferation and carcinogenesis in the endometrium.\",\n      \"method\": \"Promoter methylation analysis, reporter assays, siRNA knockdown in endometrial carcinoma cell lines\",\n      \"journal\": \"Nature\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — epigenetic mechanism established with functional cell proliferation readout; single study\",\n      \"pmids\": [\"16355216\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"ASH2L associates with ERα and is recruited to cis-regulatory elements of PAX2, altering histone H3K4me3 and H3K27me3 levels to enhance ERα-mediated transactivation of PAX2 in endometrial cancer cells.\",\n      \"method\": \"ChIP-seq, co-IP (ASH2L–ERα), siRNA knockdown, histone modification analysis\",\n      \"journal\": \"Cancer Science\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — ChIP-seq + co-IP + histone modification readout in a single study\",\n      \"pmids\": [\"32279431\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"PAX2 is a paired-domain transcription factor that binds specific DNA sequences through its paired domain and acts as either a transcriptional activator or repressor depending on cofactor context: it activates target genes (including WNT4, WNT5A, NAIP, ADAM10, Brn1, IL-5) by recruiting the PTIP adaptor and histone methyltransferase complexes, while it is switched to a repressor by Groucho/TLE proteins whose recruitment is facilitated by the phosphatase PPM1B dephosphorylating the Pax2 activation domain; JNK-mediated phosphorylation of the activation domain promotes transactivation, and this is counteracted by Grg4; in development, Pax2 is essential for nephric lineage specification (together with Pax8), renal mesenchymal-to-epithelial transition, optic fissure closure, and cochlear morphogenesis, while its expression is regulated upstream by WT1 (repression), p53, TLX, BMP7/SHH (via TLX), and angiotensin II/AT2R/JAK2-STAT signaling, and its protein stability is negatively regulated post-translationally by PHD3-mediated targeting for proteasomal destruction.\"\n}\n```","stage2_raw":"```json\n{\n  \"mechanistic_narrative\": \"PAX2 is a paired-domain transcription factor that plays essential roles in kidney, eye, ear, and midbrain-hindbrain boundary development by controlling nephric lineage specification, mesenchymal-to-epithelial transition, optic fissure closure, and cochlear morphogenesis [PMID:8951055, PMID:12435636, PMID:8383297]. PAX2 binds DNA through its paired domain and activates transcription of target genes including WNT4, WNT5A, NAIP, Brn1, ADAM10, and IL-5 via its C-terminal activation domain (residues 279–373), which recruits the BRCT-domain adaptor PTIP to engage histone methyltransferase complexes; JNK-mediated phosphorylation of this domain promotes transactivation [PMID:8702876, PMID:10908331, PMID:16368682, PMID:14532124]. PAX2 is converted from an activator to a repressor by Groucho/TLE family corepressors, which recruit the phosphatase PPM1B to dephosphorylate the activation domain, displacing PTIP and inhibiting H3K4 methylation at target loci [PMID:14532124, PMID:25631048]. Loss-of-function mutations in PAX2 cause renal-coloboma syndrome and focal segmental glomerulosclerosis through haploinsufficiency or dominant-negative impairment of DNA binding and transactivation [PMID:20221250, PMID:24676634].\",\n  \"teleology\": [\n    {\n      \"year\": 1993,\n      \"claim\": \"Deregulated Pax2 expression in transgenic mice established that PAX2 must be tightly regulated for normal kidney epithelial differentiation, revealing it as a dosage-sensitive developmental regulator rather than simply required for kidney induction.\",\n      \"evidence\": \"Transgenic mice with constitutive Pax2 expression showing nephrotic syndrome-like histology\",\n      \"pmids\": [\"8383297\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Target genes mediating the gain-of-function phenotype were unknown\", \"Whether the effect was cell-autonomous in specific nephron segments was not determined\"]\n    },\n    {\n      \"year\": 1995,\n      \"claim\": \"The discovery that WT1 directly represses Pax2 transcription via binding in the 5' leader established the first upstream regulator of PAX2 and linked PAX2 silencing to podocyte differentiation.\",\n      \"evidence\": \"DNase I footprinting of WT1 on Pax2 promoter and CAT reporter assays in co-transfection experiments\",\n      \"pmids\": [\"7720589\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Whether WT1 repression is sufficient for Pax2 downregulation in vivo was not tested by WT1 conditional deletion at this point\"]\n    },\n    {\n      \"year\": 1996,\n      \"claim\": \"Pax2 knockout mice revealed its indispensable role in optic fissure closure, cochlear development, and optic chiasm formation, defining the scope of PAX2 developmental requirements beyond kidney.\",\n      \"evidence\": \"Pax2-null mice analyzed by paint-fill, histology, and gene expression\",\n      \"pmids\": [\"8951055\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Downstream target genes in eye and ear were not identified\", \"Cell-autonomous versus non-autonomous effects were not resolved\"]\n    },\n    {\n      \"year\": 1996,\n      \"claim\": \"Mapping of the PAX2 transactivation domain (aa 279–373) and identification of the octapeptide as an intrinsic repression domain established the modular architecture governing PAX2's dual activator/repressor function.\",\n      \"evidence\": \"GAL4 fusion deletion mapping with reporter assays in tissue culture\",\n      \"pmids\": [\"8702876\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Cofactors mediating octapeptide-dependent repression were not yet identified\", \"Post-translational modifications of the activation domain were unknown\"]\n    },\n    {\n      \"year\": 2000,\n      \"claim\": \"Identification of PTIP as a direct binding partner of the PAX2 activation domain linked PAX2 to active chromatin and histone-modifying machinery, providing the first mechanistic explanation for how PAX2 activates transcription.\",\n      \"evidence\": \"Yeast two-hybrid, in vitro pulldown, and co-localization in nuclear matrix fractions\",\n      \"pmids\": [\"10908331\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"The specific histone modifications deposited via PTIP at PAX2 target genes were not determined\", \"Whether PTIP is required for all PAX2-dependent activation was untested\"]\n    },\n    {\n      \"year\": 2002,\n      \"claim\": \"Pax2/Pax8 double-knockout and Pax2 misexpression experiments demonstrated that Pax2 (with Pax8) is the earliest specification factor for the entire nephric lineage, resolving its position at the top of the kidney developmental hierarchy.\",\n      \"evidence\": \"Double-mutant mice lacking all nephric structures; retroviral Pax2 misexpression inducing ectopic nephric tissue in chick\",\n      \"pmids\": [\"12435636\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Direct transcriptional targets mediating nephric specification (beyond Lim1 and c-Ret) were not identified\", \"Relative contributions of Pax2 versus Pax8 were not fully resolved\"]\n    },\n    {\n      \"year\": 2003,\n      \"claim\": \"The finding that Groucho/Grg4 suppresses PAX2 transactivation by specifically blocking JNK-mediated phosphorylation of the activation domain — independently of histone deacetylation — revealed the molecular switch converting PAX2 from activator to repressor.\",\n      \"evidence\": \"Co-IP, in vitro kinase assay, reporter assays with HDAC inhibitors and mutagenesis\",\n      \"pmids\": [\"14532124\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"The JNK phosphorylation sites on PAX2 were not mapped\", \"Whether Grg4 recruitment occurs at all PAX2 target loci was unknown\"]\n    },\n    {\n      \"year\": 2005,\n      \"claim\": \"Direct PAX2 binding to and activation of the WNT4 promoter connected PAX2 to the mesenchymal-to-epithelial transition signal, identifying the first direct downstream effector linking PAX2 to nephron induction.\",\n      \"evidence\": \"EMSA, reporter assays, and reduced Wnt4 mRNA in Pax2 heterozygous kidneys\",\n      \"pmids\": [\"16368682\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Whether PAX2 is sufficient for WNT4 activation in the absence of cofactors was not established\", \"Other PAX2 targets required for MET were not mapped\"]\n    },\n    {\n      \"year\": 2008,\n      \"claim\": \"PAX2 was shown to mediate ER-dependent ERBB2 repression in breast cancer, with PAX2 and AIB-1/SRC-3 competing at the ERBB2 locus, establishing PAX2 as a determinant of tamoxifen response and expanding its role beyond development.\",\n      \"evidence\": \"ChIP, co-IP, reporter assays, and siRNA knockdown in human breast cancer cell lines\",\n      \"pmids\": [\"19005469\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Structural basis of PAX2–AIB-1 competition at the ERBB2 element was not resolved\", \"Whether PAX2 represses ERBB2 in normal breast epithelium was unknown\"]\n    },\n    {\n      \"year\": 2010,\n      \"claim\": \"Characterization of a PAX2 disease missense mutation (T74A) as a hypomorphic allele with reduced transactivation and protein stability — without loss of DNA binding — revealed that PAX2-associated renal disease can arise from quantitative functional impairment rather than complete loss of DNA recognition.\",\n      \"evidence\": \"Reporter assays, in vitro binding, protein stability analysis, and mouse knock-in model\",\n      \"pmids\": [\"20221250\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"The mechanism by which T74A reduces protein stability was not determined\", \"Whether all renal-coloboma mutations act as hypomorphs was not systematically tested\"]\n    },\n    {\n      \"year\": 2015,\n      \"claim\": \"Identification of PPM1B as the phosphatase within the Groucho repressor complex that dephosphorylates the PAX2 activation domain and displaces PTIP completed the activator-to-repressor switch mechanism, showing that H3K4 methylation status at PAX2 targets is dynamically controlled by the balance between JNK phosphorylation and PPM1B dephosphorylation.\",\n      \"evidence\": \"Co-IP, ChIP, reporter assays, siRNA knockdown of PPM1B, histone methylation analysis\",\n      \"pmids\": [\"25631048\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Whether PPM1B activity is itself regulated in a tissue-specific manner was not explored\", \"The full set of loci where the PTIP/PPM1B switch operates genome-wide was not mapped\"]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"Inducible Pax2/Pax8 deletion in adult kidney demonstrated a maintained role for these factors in regulating urine concentration through urea transporter and aquaporin expression, extending PAX2 function from developmental patterning to adult homeostasis.\",\n      \"evidence\": \"Conditional double KO in adult mice with gene expression profiling and ChIP for histone methyltransferase recruitment\",\n      \"pmids\": [\"32381599\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Individual contributions of Pax2 versus Pax8 to adult collecting duct gene regulation were not separated\", \"Whether PAX2 directly binds Slc14a2 regulatory elements (as opposed to Pax8) was not resolved\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"A genome-wide map of direct PAX2 binding sites and the structural basis for its context-dependent switch between activation and repression remain to be determined.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Low\",\n      \"gaps\": [\"No genome-wide ChIP-seq for PAX2 across developmental stages has been reported in the timeline\", \"No crystal structure of PAX2 paired domain bound to a physiological target site is described\", \"How tissue-specific cofactor availability determines activator versus repressor output at individual loci is unresolved\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0003677\", \"supporting_discovery_ids\": [5, 6, 9, 17, 27]},\n      {\"term_id\": \"GO:0140110\", \"supporting_discovery_ids\": [3, 5, 7, 8, 9, 10, 11, 12, 19, 26]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005634\", \"supporting_discovery_ids\": [6, 17]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"GO:0074160\", \"supporting_discovery_ids\": [3, 5, 7, 8, 9, 12, 26]},\n      {\"term_id\": \"R-HSA-1266738\", \"supporting_discovery_ids\": [0, 1, 2, 22, 23]},\n      {\"term_id\": \"R-HSA-162582\", \"supporting_discovery_ids\": [9, 19, 21]},\n      {\"term_id\": \"R-HSA-4839726\", \"supporting_discovery_ids\": [6, 8]}\n    ],\n    \"complexes\": [],\n    \"partners\": [\n      \"PTIP\",\n      \"GRG4\",\n      \"PPM1B\",\n      \"WT1\",\n      \"PHD3\",\n      \"AIB1\",\n      \"TLX\",\n      \"ASH2L\"\n    ],\n    \"other_free_text\": []\n  }\n}\n```"}