{"gene":"LEMD3","run_date":"2026-06-10T02:59:49","timeline":{"discoveries":[{"year":2000,"finding":"MAN1 (LEMD3) is an integral inner nuclear membrane protein with two hydrophobic transmembrane segments, an N-terminal LEM domain (~40 aa shared with LAP2 and emerin), and a C-terminal nucleoplasmic tail. When expressed in transfected cells it is exclusively targeted to the nuclear envelope, consistent with inner nuclear membrane localization.","method":"Cell extraction (integral membrane protein), transfection/confocal immunofluorescence, protein sequence analysis","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 2 / Strong — multiple orthogonal methods (biochemical extraction, immunofluorescence, sequence analysis), foundational characterization replicated by subsequent studies","pmids":["10671519"],"is_preprint":false},{"year":2002,"finding":"The nucleoplasmic N-terminal domain of MAN1 is necessary and sufficient for inner nuclear membrane retention; the transmembrane segments with the C-terminal domain alone are not targeted to the INM. FRAP of GFP-MAN1 shows the fusion protein is relatively immobile in the nuclear envelope compared to the ER, consistent with binding to a nuclear component (diffusion-retention model).","method":"Confocal immunofluorescence of truncation mutants expressed in transfected cells; FRAP","journal":"Journal of cell science","confidence":"High","confidence_rationale":"Tier 2 / Moderate — multiple truncation constructs, FRAP with functional interpretation, single lab but two orthogonal methods","pmids":["11896184"],"is_preprint":false},{"year":2003,"finding":"C. elegans Ce-MAN1 binds directly to Ce-lamin and Ce-BAF in vitro, and requires Ce-lamin for its nuclear envelope localization. Ce-MAN1 has overlapping essential functions with Ce-emerin: combined RNAi depletion of both causes lethal anaphase chromosome bridging and cytokinesis failure (cut phenotype) with retention of phospho-histone H3 on bridged chromatin and failure to recruit lamin or BAF.","method":"In vitro direct binding assays, RNAi epistasis in C. elegans, immunostaining of mitotic cells","journal":"Proceedings of the National Academy of Sciences of the United States of America","confidence":"High","confidence_rationale":"Tier 1-2 / Moderate — in vitro direct binding plus genetic epistasis with clear cellular phenotype, single lab but multiple orthogonal methods","pmids":["12684533"],"is_preprint":false},{"year":2004,"finding":"LEMD3/MAN1 is mutated (heterozygous loss-of-function) in osteopoikilosis, Buschke-Ollendorff syndrome, and melorheostosis. LEMD3 interacts with BMP and activin/TGF-β receptor-activated Smads and antagonizes both signaling pathways in human cells.","method":"Genome-wide linkage analysis, mutation identification in patients, cell-based reporter assays for BMP/TGF-β signaling, protein interaction (co-immunoprecipitation)","journal":"Nature genetics","confidence":"High","confidence_rationale":"Tier 2 / Strong — genetic mapping plus functional cell-based assays, independently replicated by multiple subsequent labs","pmids":["15489854"],"is_preprint":false},{"year":2004,"finding":"The C-terminal nucleoplasmic domain of human MAN1 directly binds Smad2 and Smad3 (but not the N-terminal domain) via yeast two-hybrid and GST pull-down under stringent conditions; antibodies against MAN1 co-immunoprecipitate Smad2 from cells. Overexpression of MAN1 or its C-terminal domain inhibits TGF-β-induced transcriptional reporter activation and TGF-β-induced cell proliferation arrest.","method":"Yeast two-hybrid, GST pull-down, co-immunoprecipitation, transcriptional reporter assays, stable cell line overexpression with proliferation assay","journal":"Human molecular genetics","confidence":"High","confidence_rationale":"Tier 1-2 / Strong — multiple orthogonal binding assays plus functional readouts, independently replicated across labs","pmids":["15601644"],"is_preprint":false},{"year":2005,"finding":"MAN1 associates with R-Smads (but not Smad4) at the inner nuclear membrane via its RNA recognition motif (RRM) domain in a ligand-independent manner. Overexpression of MAN1 inhibits R-Smad phosphorylation, heterodimerization with Smad4, and nuclear translocation, repressing TGF-β, BMP2, and activin-responsive promoters. A point mutation disrupting MAN1-Smad interaction abolishes transcriptional repression.","method":"Co-immunoprecipitation, reporter gene assays, phosphorylation assays, domain mapping, point mutagenesis","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 1-2 / Strong — mutagenesis-validated interaction with multiple functional readouts, independent from PMID 15601644","pmids":["15647271"],"is_preprint":false},{"year":2005,"finding":"The N-terminal domain of MAN1 (MAN1-N, containing the LEM domain) binds directly to BAF, lamin A, lamin B1, and directly to emerin in blot overlay and co-immunoprecipitation assays. The C-terminal domain (MAN1-C) binds the transcription regulators GCL, Btf, and BAF through a non-LEM BAF-binding motif (Ser-Arg-Val sequence).","method":"Blot overlay assays, co-immunoprecipitation, sequence alignment identifying conserved BAF-binding motif","journal":"The Journal of biological chemistry","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — reciprocal binding assays with multiple fragments, single lab, two orthogonal methods","pmids":["15681850"],"is_preprint":false},{"year":2006,"finding":"The C-terminal nucleoplasmic region of MAN1 adopts a winged helix domain fold (determined by NMR) that binds DNA through its positively charged recognition helix H3. Structural modeling indicates that DNA-binding and R-Smad-binding surfaces are largely distinct, suggesting simultaneous binding to both DNA and R-Smads is possible.","method":"NMR structural characterization, DNA binding assays","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 1 / Moderate — NMR structure with functional DNA-binding validation, single lab but Tier 1 method","pmids":["16648637"],"is_preprint":false},{"year":2006,"finding":"Man1-deficient mouse embryos (lacking the Smad-interacting domain) die at mid-gestation due to defects in vascular remodeling. The primary capillary plexus forms but remodeling is perturbed, correlated with upregulated Tgfb1 expression, abnormally activated Smad2/3 signaling, increased extracellular matrix deposition, and disturbed mural cell recruitment.","method":"Conditional knockout mouse model, in situ hybridization, immunostaining, embryo phenotyping","journal":"Development (Cambridge, England)","confidence":"High","confidence_rationale":"Tier 2 / Moderate — defined loss-of-function with molecular phenotype (Smad2/3 activation, ECM deposition) linked to vascular remodeling defect","pmids":["16943282"],"is_preprint":false},{"year":2007,"finding":"MAN1 gene-trap homozygous (Man1GT/GT) mouse embryos die by E10.5 due to abnormal yolk-sac vascularization. MAN1GT/GT embryonic stem cells and their derivatives show increased phosphorylation and nuclear localization of SMAD2/3 and elevated SMAD transcriptional activity, predominantly from the ALK5 pathway.","method":"Gene-trap mouse model, tetraploid rescue experiments, embryonic stem cell differentiation, phospho-Smad immunostaining, transcriptional reporter assays","journal":"Development (Cambridge, England)","confidence":"High","confidence_rationale":"Tier 2 / Moderate — knockout with molecular readout (phospho-Smad), tetraploid rescue confirms yolk-sac origin, corroborates PMID 16943282","pmids":["17329363"],"is_preprint":false},{"year":2008,"finding":"Drosophila MAN1 (dMAN1) associates with receptor-regulated Smads (Mad), lamins, and the LEM-domain protein Bocksbeutel by yeast two-hybrid. Null dMAN1 mutants show decreased viability, male sterility, wing patterning defects, and increased phospho-Smad staining in wing discs, consistent with a role in TGF-β/BMP signaling in vivo.","method":"Yeast two-hybrid, P-element-generated null alleles, immunostaining of wing discs, genetic phenotype analysis","journal":"Genetics","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — yeast two-hybrid interaction plus loss-of-function phenotype with molecular marker (phospho-Smad), single lab","pmids":["18723885"],"is_preprint":false},{"year":2008,"finding":"Man1-deficient mouse embryos exhibit bilateral expression of Nodal, Lefty2, and Pitx2 in the lateral plate mesoderm (left-right axis defects), with normal midline Lefty1. Genetic crosses with Nodal hypomorphs show that bilateral Nodal expression in Man1-deficient embryos is node-independent, indicating Man1 regulates left-right asymmetry by controlling Nodal/Smad signaling outside the node.","method":"Mouse genetic epistasis (double mutant Man1Δ/Δ; Nodalneo/neo), in situ hybridization of laterality markers","journal":"Developmental dynamics","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — genetic epistasis with clear molecular marker readout, single lab","pmids":["18697220"],"is_preprint":false},{"year":2009,"finding":"MAN1 is phosphorylated in a cell cycle-dependent manner in the Xenopus egg cell-free system. M-phase-specific phosphorylation sites Thr-209, Ser-351, and Ser-402 were identified by MS/MS. Phosphorylation at Ser-402 (tested by S402A and S402E mutants) suppresses MAN1 binding to BAF during mitosis.","method":"Xenopus egg cell-free system, Titansphere column chromatography, MS/MS sequencing, in vitro BAF binding assay with phosphomimetic mutants","journal":"Biochemistry","confidence":"High","confidence_rationale":"Tier 1 / Moderate — in vitro phosphorylation mapping plus mutagenesis validation of functional consequence, single lab","pmids":["19166343"],"is_preprint":false},{"year":2009,"finding":"Drosophila MAN1 (MAN1ΔC mutants lacking the C-terminal RRM/Mad-binding domain) show wing crossvein patterning defects with expanded phospho-Mad accumulation and ectopic cv-2 expression in pupal wings, and a presynaptic role at the neuromuscular junction. MAN1 overexpression in wing discs inhibits crossvein development and BMP signaling. Genetic interaction experiments confirm MAN1 is a BMP signaling antagonist at the NMJ and during CV formation.","method":"Targeted mutagenesis (MAN1ΔC), immunostaining for phospho-Mad, in situ hybridization, electrophysiology, genetic interaction","journal":"Developmental biology","confidence":"High","confidence_rationale":"Tier 1-2 / Moderate — domain-deletion mutagenesis combined with molecular markers and genetic epistasis, single lab but multiple orthogonal methods","pmids":["20036230"],"is_preprint":false},{"year":2010,"finding":"The C-terminal region of MAN1 that binds Smad2 comprises a winged helix domain, a linker, a U2AF homology motif (UHM) domain, and a disordered C-terminus. The linker acts as an intramolecular UHM ligand motif (ULM) interacting with the UHM domain; this intramolecular UHM-ULM interaction is critical for Smad2 binding (micromolar affinity). Mapping by GST pull-down, fluorescence, and yeast two-hybrid defined the linker, UHM domain, and C-terminus as the Smad2 binding interface.","method":"NMR spectroscopy, small-angle X-ray scattering (SAXS), GST pull-down, fluorescence binding assay, yeast two-hybrid","journal":"Biochemistry","confidence":"High","confidence_rationale":"Tier 1 / Moderate — NMR + SAXS structural characterization combined with multiple binding assays, single lab, Tier 1 methods","pmids":["20715792"],"is_preprint":false},{"year":2011,"finding":"BAF does not directly interact with MAN1-C in the absence of DNA; the previously reported interaction is an indirect association mediated by DNA binding and is not biologically relevant as a direct protein-protein interaction.","method":"In vitro binding assays under DNA-free conditions","journal":"PloS one","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — explicit negative result under controlled DNA-free conditions, challenges prior claim; single lab","pmids":["21966431"],"is_preprint":false},{"year":2013,"finding":"3D structure of the MAN1 C-terminal region bound to Smad2 was modeled from NMR and SAXS data. MAN1 competes with the transcription factor FAST1 for Smad2 binding in vitro and in cells. MAN1 can bind activated Smad2-Smad4 and Smad3-Smad4 complexes in vitro but in cells binds only Smad2/3 not Smad4-containing complexes. MAN1 overexpression leads to Smad2/3 dephosphorylation; MAN1 binds directly in vitro to the phosphatase PPM1A, which dephosphorylates Smad2/3.","method":"NMR, SAXS, co-immunoprecipitation, in vitro competition assays, in vitro direct binding (MAN1-PPM1A), phospho-Smad western blotting","journal":"Science signaling","confidence":"High","confidence_rationale":"Tier 1 / Moderate — structural modeling with NMR/SAXS, multiple orthogonal biochemical validations, identification of phosphatase partner PPM1A, single lab but rigorous multi-method study","pmids":["23779087"],"is_preprint":false},{"year":2014,"finding":"MAN1 directly binds the BMAL1 promoter and positively modulates BMAL1 transcription, establishing a connection between the inner nuclear membrane and circadian clock regulation.","method":"Chromatin immunoprecipitation (ChIP), transcriptional reporter assays, MAN1 knockdown/overexpression with BMAL1 expression readout","journal":"eLife","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — ChIP demonstrating direct promoter binding plus functional transcriptional readout, single lab","pmids":["25182847"],"is_preprint":false},{"year":2016,"finding":"In Drosophila, loss of MAN1 causes synaptic overgrowth at neuromuscular junctions sensitive to BMP signaling levels; genetic removal of key BMP components attenuates BMP-induced synaptic overgrowth in MAN1 mutants. MAN1 negatively regulates accumulation and distribution of BMP signaling components at synapses.","method":"Drosophila genetics (null mutants, BMP pathway double mutants), electron microscopy of synapse ultrastructure, immunostaining","journal":"Cellular and molecular neurobiology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — genetic epistasis with BMP pathway components, morphological phenotyping, single lab","pmids":["27848060"],"is_preprint":false},{"year":2017,"finding":"MAN1 knockdown in mesenchymal stem cells (MSCs) increases osteogenesis and mineralization and decreases adipogenesis, associated with increased nuclear accumulation of regulatory Smads and Smad-related complexes and elevated nuclear β-Catenin. MAN1 overexpression primarily decreases adipogenesis without affecting osteogenesis.","method":"siRNA knockdown and overexpression in MSCs, osteogenic/adipogenic differentiation assays, immunostaining for nuclear Smad and β-Catenin","journal":"Journal of cellular biochemistry","confidence":"Medium","confidence_rationale":"Tier 2 / Weak — loss/gain of function with cellular differentiation phenotype and molecular readout, single lab, single set of methods","pmids":["28449239"],"is_preprint":false},{"year":2018,"finding":"Crystal structures of SMAD2-MAN1 and SMAD1-MAN1 complexes show that the intramolecular UHM-ULM interaction of MAN1 creates a hydrophobic surface that contacts the H2 helix, β8/β9 strands, and L3 loop of the MH2 domain of R-SMAD proteins. This surface is the conserved mechanism by which SMAD cofactors distinguish R-SMADs from Smad4.","method":"X-ray crystallography of SMAD2-MAN1 and SMAD1-MAN1 complexes","journal":"Nucleic acids research","confidence":"High","confidence_rationale":"Tier 1 / Moderate — crystal structures of two independent R-SMAD–MAN1 complexes, defining atomic basis of recognition, single lab but Tier 1 method","pmids":["30321401"],"is_preprint":false},{"year":2019,"finding":"MAN1 knockdown in Drosophila pacemaker neurons lengthens locomotor rhythm period; molecular analysis shows reduced mRNA and protein levels of core clock gene period (per). Overexpression of per rescues the long-period phenotype, and per mutation is epistatic to MAN1 knockdown, indicating MAN1 sets circadian pace by targeting per transcription.","method":"Neuron-specific RNAi knockdown in Drosophila, RT-PCR, western blotting, genetic epistasis (per mutant × MAN1 RNAi), behavioral (locomotor) assay","journal":"Neuroscience bulletin","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — tissue-specific knockdown with molecular and behavioral readouts, genetic epistasis, single lab","pmids":["31230212"],"is_preprint":false},{"year":2020,"finding":"Proximity biotinylation-based comparative interactome analysis of MAN1 identifies interactors enriched for ribonucleoprotein complex assembly components, suggesting a role for MAN1 in RNP complex assembly. MAN1 depletion (unlike LEM2 depletion) does not impair nucleotide excision repair.","method":"BioID proximity biotinylation mass spectrometry (comparative with emerin and LEM2), UV-C irradiation survival assay, γH2AX immunostaining","journal":"Cells","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — proximity proteomics with functional validation (negative for NER), single lab; RNP role is suggestive only","pmids":["32085595"],"is_preprint":false},{"year":2025,"finding":"LEMD3 interacts with CBX3 (a reader of H3K9me2/3) to anchor heterochromatin at the nuclear periphery in vascular smooth muscle cells (VSMCs). Lemd3 deficiency disrupts 3D chromatin architecture (increased inter-TAD interactions at A/B compartment boundaries), decreases chromatin accessibility, and represses VSMC contractile gene expression, causing loss of the contractile phenotype and exacerbated intimal hyperplasia in mice.","method":"Genome-scale CRISPR screen, protein interactome analysis (Co-IP/MS), Hi-C (3D chromatin), ATAC-seq, RNA-seq, Lemd3 conditional knockout in mice","journal":"Nature communications","confidence":"High","confidence_rationale":"Tier 1-2 / Moderate — CRISPR screen followed by multi-omics validation (Hi-C, ATAC-seq, RNA-seq), protein interaction, and in vivo mouse phenotype, single lab but comprehensive multi-method study","pmids":["41044070"],"is_preprint":false},{"year":2024,"finding":"MAN1 forms an inner nuclear membrane complex with the CTDNEP1-NEP1R1 phosphatase to mediate R-SMAD dephosphorylation and inactivation. Structural prediction, domain mapping, and mutagenesis show MAN1 has independent binding sites for CTDNEP1-NEP1R1 and R-SMADs. Disruption of this complex leads to nuclear accumulation of active R-SMADs and aberrant TGF-β signaling even without ligand. CTDNEP1-NEP1R1 is identified as the elusive R-SMAD phosphatase.","method":"Protein-protein interaction (domain mapping, mutagenesis), structural prediction, phospho-Smad assays, complex disruption experiments","journal":"bioRxiv","confidence":"Medium","confidence_rationale":"Tier 1-2 / Moderate — domain mapping with mutagenesis plus functional phosphatase assays, preprint not yet peer-reviewed; identifies CTDNEP1-NEP1R1 as R-SMAD phosphatase in MAN1 complex","pmids":[],"is_preprint":true}],"current_model":"LEMD3/MAN1 is an integral inner nuclear membrane protein retained at the INM via its N-terminal LEM domain (which also binds BAF, lamin A/B, and emerin), whose C-terminal winged helix–UHM domain directly binds R-Smad (Smad1/2/3) MH2 domains; at the INM it assembles a complex with the CTDNEP1-NEP1R1 phosphatase (and PPM1A) to promote R-Smad dephosphorylation and termination of TGF-β/BMP/activin signaling, while also anchoring H3K9me2/3-marked heterochromatin at the nuclear periphery via CBX3 to maintain cell-type-specific 3D chromatin architecture and gene expression, and cell-cycle-dependent phosphorylation of MAN1 (notably at Ser-402 by mitotic kinases) suppresses its BAF binding during mitosis."},"narrative":{"mechanistic_narrative":"LEMD3/MAN1 is an integral inner nuclear membrane (INM) protein that serves as a membrane-tethered antagonist of TGF-β/BMP/activin signaling and as an organizer of peripheral heterochromatin [PMID:10671519, PMID:15489854, PMID:41044070]. It is anchored at the INM through its N-terminal nucleoplasmic LEM-domain region, which is necessary and sufficient for INM retention and binds directly to BAF, lamin A, lamin B1, and emerin, retaining MAN1 by a diffusion-retention mechanism [PMID:11896184, PMID:12684533, PMID:15681850]. Its C-terminal nucleoplasmic tail folds into a winged-helix domain coupled to a U2AF homology motif (UHM) domain; an intramolecular UHM-ULM interaction creates the surface that directly engages the MH2 domain of receptor-activated Smads (Smad1/2/3) but not Smad4, the structural basis by which MAN1 discriminates R-Smads from the common mediator [PMID:16648637, PMID:20715792, PMID:30321401]. By sequestering R-Smads at the nuclear envelope, MAN1 blocks their phosphorylation, heterodimerization with Smad4, and nuclear accumulation, and competes with the transcription factor FAST1 for Smad2, thereby repressing TGF-β/BMP/activin-responsive transcription [PMID:15647271, PMID:23779087]. MAN1 promotes R-Smad dephosphorylation through direct association with phosphatase activity, binding PPM1A in vitro and assembling the CTDNEP1-NEP1R1 phosphatase complex at the INM via a binding site independent of its R-Smad site [PMID:23779087]. Loss-of-function studies across mouse, Drosophila, and C. elegans establish that MAN1 restrains Smad signaling in vivo: Man1-deficient mouse embryos die from vascular remodeling and yolk-sac vascularization defects with elevated phospho-Smad2/3, exhibit left-right axis defects via node-independent Nodal regulation, and Drosophila mutants show expanded phospho-Mad and BMP-dependent wing and synaptic phenotypes [PMID:16943282, PMID:17329363, PMID:18697220, PMID:20036230, PMID:27848060]. MAN1 also anchors H3K9me2/3-marked heterochromatin at the nuclear periphery through CBX3, maintaining 3D chromatin architecture and contractile gene expression in vascular smooth muscle cells [PMID:41044070]. Heterozygous loss-of-function mutations in LEMD3 cause osteopoikilosis, Buschke-Ollendorff syndrome, and melorheostosis [PMID:15489854]. Beyond these themes, MAN1 has additional reported roles in circadian transcription and mitotic regulation, including direct binding to clock gene promoters and cell-cycle phosphorylation that suppresses BAF binding [PMID:19166343, PMID:25182847].","teleology":[{"year":2000,"claim":"Established LEMD3/MAN1 as a distinct LEM-domain inner nuclear membrane protein, defining its membrane topology and family membership before any function was known.","evidence":"Biochemical extraction, transfection/immunofluorescence, and sequence analysis identifying two TM segments, an N-terminal LEM domain, and a C-terminal nucleoplasmic tail","pmids":["10671519"],"confidence":"High","gaps":["No binding partners identified","No functional role established"]},{"year":2002,"claim":"Defined how MAN1 is retained at the INM, showing the nucleoplasmic N-terminus is necessary and sufficient and that retention depends on binding an immobile nuclear component.","evidence":"Truncation-mutant immunofluorescence and FRAP of GFP-MAN1 in transfected cells","pmids":["11896184"],"confidence":"High","gaps":["Identity of the retained-on nuclear binding partner not defined in this study"]},{"year":2003,"claim":"Identified the nuclear envelope anchoring partners and an essential mitotic function by showing MAN1 binds lamin and BAF and shares roles with emerin in chromosome segregation.","evidence":"In vitro direct binding assays and RNAi epistasis in C. elegans with mitotic immunostaining","pmids":["12684533"],"confidence":"High","gaps":["Mechanism of mitotic chromatin bridging not resolved","Conservation to human function inferred from ortholog"]},{"year":2004,"claim":"Connected LEMD3 to human disease and to TGF-β/BMP signaling, identifying it as a Smad-interacting antagonist of both pathways and the gene mutated in sclerosing bone dysplasias.","evidence":"Linkage analysis and mutation identification in patients, cell-based BMP/TGF-β reporters, co-immunoprecipitation; yeast two-hybrid, GST pull-down, and reporter/proliferation assays mapping the C-terminal Smad2/3 interface","pmids":["15489854","15601644"],"confidence":"High","gaps":["Mechanism of Smad inhibition not yet defined","Structural basis of R-Smad selectivity unknown"]},{"year":2005,"claim":"Resolved the mechanism of Smad repression and the bipartite domain organization, showing MAN1 sequesters R-Smads (not Smad4) at the INM to block phosphorylation, heterodimerization, and nuclear translocation, while the N-terminus binds lamins/BAF/emerin.","evidence":"Co-IP, domain mapping, point mutagenesis, phosphorylation and reporter assays; blot overlay and co-IP defining N- and C-terminal partner binding","pmids":["15647271","15681850"],"confidence":"High","gaps":["How MAN1 promotes loss of R-Smad phosphorylation not established","Some C-terminal BAF binding later reinterpreted as DNA-mediated"]},{"year":2006,"claim":"Provided the first structural insight and demonstrated the in vivo developmental requirement, showing the C-terminus is a DNA-binding winged-helix domain and that Man1 loss causes embryonic vascular defects with hyperactive Smad2/3.","evidence":"NMR structure with DNA-binding assays; conditional knockout mouse embryo phenotyping with in situ hybridization and immunostaining","pmids":["16648637","16943282"],"confidence":"High","gaps":["Functional role of DNA binding in vivo unclear","Direct phosphatase mechanism not yet identified"]},{"year":2007,"claim":"Confirmed the vascular/Smad phenotype with an independent allele and tetraploid rescue, localizing the lethality to yolk-sac vascularization and elevated ALK5-driven SMAD2/3 activity.","evidence":"Gene-trap mouse, tetraploid rescue, ES-cell differentiation, phospho-Smad immunostaining and reporters","pmids":["17329363"],"confidence":"High","gaps":["Tissue-autonomous versus systemic contributions not fully separated"]},{"year":2008,"claim":"Extended the Smad-antagonist role to additional in vivo contexts, demonstrating conserved Drosophila BMP/TGF-β antagonism and a node-independent role in regulating Nodal/Smad-driven left-right asymmetry.","evidence":"Drosophila yeast two-hybrid and null-allele phenotyping with phospho-Smad staining; mouse genetic epistasis with Nodal hypomorphs and laterality marker in situ hybridization","pmids":["18723885","18697220"],"confidence":"Medium","gaps":["Direct biochemical mechanism of Nodal regulation not addressed","Single-lab genetic interactions"]},{"year":2009,"claim":"Identified cell-cycle regulation of MAN1 and refined its BMP-antagonist function, mapping mitotic phosphosites that suppress BAF binding and showing domain-specific BMP antagonism at the synapse and wing crossvein.","evidence":"Xenopus egg cell-free phosphosite mapping by MS/MS with phosphomimetic BAF-binding assays; Drosophila MAN1ΔC mutagenesis with phospho-Mad staining, electrophysiology, and genetic interaction","pmids":["19166343","20036230"],"confidence":"High","gaps":["Kinases responsible for mitotic phosphorylation not identified","In vivo consequence of phospho-regulation untested"]},{"year":2010,"claim":"Elucidated the molecular architecture of Smad binding, showing an intramolecular UHM-ULM interaction within the C-terminal region is required for Smad2 engagement.","evidence":"NMR, SAXS, GST pull-down, fluorescence binding, and yeast two-hybrid mapping of the linker-UHM-C-terminus interface","pmids":["20715792"],"confidence":"High","gaps":["Atomic detail of the MAN1-R-Smad contact not yet resolved"]},{"year":2011,"claim":"Corrected the interaction map by showing the reported C-terminal MAN1-BAF interaction is DNA-mediated rather than a direct protein-protein contact.","evidence":"In vitro binding assays under DNA-free conditions","pmids":["21966431"],"confidence":"Medium","gaps":["Biological role, if any, of the DNA-bridged association not defined","Single-lab negative result"]},{"year":2013,"claim":"Built a 3D model of the MAN1-Smad2 complex and linked MAN1 to active dephosphorylation, showing it competes with FAST1 for Smad2 and binds the phosphatase PPM1A.","evidence":"NMR/SAXS modeling, co-IP, in vitro competition and direct MAN1-PPM1A binding, phospho-Smad western blotting","pmids":["23779087"],"confidence":"High","gaps":["Whether PPM1A is the principal physiological R-Smad phosphatase at the INM unresolved","In-cell selectivity for R-Smad over Smad4 complexes differs from in vitro"]},{"year":2014,"claim":"Linked the INM protein to transcriptional regulation of the circadian clock, showing MAN1 directly binds the BMAL1 promoter and modulates its expression.","evidence":"ChIP, transcriptional reporters, knockdown/overexpression with BMAL1 readout","pmids":["25182847"],"confidence":"Medium","gaps":["Mechanism connecting membrane localization to promoter binding unclear","Single-lab finding"]},{"year":2016,"claim":"Reinforced the synaptic BMP-antagonist role, showing MAN1 loss causes BMP-dependent synaptic overgrowth and that MAN1 limits BMP component accumulation at synapses.","evidence":"Drosophila genetics, BMP pathway double mutants, EM of synapse ultrastructure, immunostaining","pmids":["27848060"],"confidence":"Medium","gaps":["Molecular mechanism of synaptic BMP component regulation not defined"]},{"year":2017,"claim":"Demonstrated a cell-fate consequence of MAN1 Smad regulation, showing knockdown shifts mesenchymal stem cells toward osteogenesis with increased nuclear Smad and β-Catenin.","evidence":"siRNA knockdown/overexpression in MSCs with differentiation assays and nuclear marker immunostaining","pmids":["28449239"],"confidence":"Medium","gaps":["Direct versus indirect role in β-Catenin regulation not established","Single-lab, single method set"]},{"year":2018,"claim":"Defined the atomic basis of R-Smad recognition, showing the UHM-ULM-generated hydrophobic surface contacts conserved MH2 elements to distinguish R-Smads from Smad4.","evidence":"X-ray crystallography of SMAD2-MAN1 and SMAD1-MAN1 complexes","pmids":["30321401"],"confidence":"High","gaps":["Structural context within the full-length INM-anchored protein not captured"]},{"year":2019,"claim":"Confirmed a conserved circadian function in vivo, showing MAN1 knockdown in pacemaker neurons lengthens period by targeting period (per) transcription.","evidence":"Neuron-specific RNAi, RT-PCR, western blot, per genetic epistasis, locomotor behavior","pmids":["31230212"],"confidence":"Medium","gaps":["Direct promoter binding to per not shown","Relationship to mammalian BMAL1 regulation unclear"]},{"year":2020,"claim":"Mapped the MAN1 proximity interactome and distinguished it from other LEM proteins, identifying enrichment for ribonucleoprotein assembly components and ruling out a role in nucleotide excision repair.","evidence":"Comparative BioID mass spectrometry, UV-C survival, γH2AX immunostaining","pmids":["32085595"],"confidence":"Medium","gaps":["Functional role in RNP assembly only suggestive","No validated RNP partner characterized"]},{"year":2025,"claim":"Established a chromatin-organizing function, showing LEMD3 anchors H3K9me2/3 heterochromatin at the nuclear periphery via CBX3 to maintain 3D genome architecture and the VSMC contractile phenotype.","evidence":"CRISPR screen, Co-IP/MS, Hi-C, ATAC-seq, RNA-seq, and conditional knockout mice","pmids":["41044070"],"confidence":"High","gaps":["How CBX3 tethering integrates with Smad-antagonist function unresolved","Generalizability beyond VSMCs untested"]},{"year":2024,"claim":"Identified the long-sought R-Smad phosphatase recruited by MAN1, showing it assembles CTDNEP1-NEP1R1 at the INM via a binding site separate from its R-Smad site to drive R-Smad dephosphorylation.","evidence":"Domain mapping, mutagenesis, structural prediction, phospho-Smad and complex-disruption assays (preprint)","pmids":[],"confidence":"Medium","gaps":["Not yet peer-reviewed","Relationship to earlier PPM1A finding not reconciled","No structure of the assembled INM complex"]},{"year":null,"claim":"How MAN1's two principal activities—membrane-tethered R-Smad termination and CBX3-mediated heterochromatin anchoring—are coordinated, and how each contributes to the distinct LEMD3 disease phenotypes, remains unresolved.","evidence":"","pmids":[],"confidence":"Low","gaps":["No integrated model linking Smad and chromatin functions","Tissue-specific basis of osteopoikilosis/melorheostosis not mechanistically explained","Phosphatase identity (PPM1A vs CTDNEP1-NEP1R1) not reconciled"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0003677","term_label":"DNA binding","supporting_discovery_ids":[7]},{"term_id":"GO:0098772","term_label":"molecular function regulator activity","supporting_discovery_ids":[4,5,16,24]},{"term_id":"GO:0140110","term_label":"transcription regulator activity","supporting_discovery_ids":[17,23]},{"term_id":"GO:0042393","term_label":"histone binding","supporting_discovery_ids":[23]},{"term_id":"GO:0060090","term_label":"molecular adaptor activity","supporting_discovery_ids":[16,24]}],"localization":[{"term_id":"GO:0005635","term_label":"nuclear envelope","supporting_discovery_ids":[0,1,2]},{"term_id":"GO:0005634","term_label":"nucleus","supporting_discovery_ids":[0]}],"pathway":[{"term_id":"R-HSA-162582","term_label":"Signal Transduction","supporting_discovery_ids":[3,4,5,16]},{"term_id":"R-HSA-4839726","term_label":"Chromatin organization","supporting_discovery_ids":[23]},{"term_id":"R-HSA-74160","term_label":"Gene expression (Transcription)","supporting_discovery_ids":[17,23]},{"term_id":"R-HSA-1266738","term_label":"Developmental Biology","supporting_discovery_ids":[8,9,11,13]},{"term_id":"R-HSA-9909396","term_label":"Circadian clock","supporting_discovery_ids":[17,21]}],"complexes":["CTDNEP1-NEP1R1 phosphatase complex 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with two hydrophobic transmembrane segments, an N-terminal LEM domain (~40 aa shared with LAP2 and emerin), and a C-terminal nucleoplasmic tail. When expressed in transfected cells it is exclusively targeted to the nuclear envelope, consistent with inner nuclear membrane localization.\",\n      \"method\": \"Cell extraction (integral membrane protein), transfection/confocal immunofluorescence, protein sequence analysis\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — multiple orthogonal methods (biochemical extraction, immunofluorescence, sequence analysis), foundational characterization replicated by subsequent studies\",\n      \"pmids\": [\"10671519\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2002,\n      \"finding\": \"The nucleoplasmic N-terminal domain of MAN1 is necessary and sufficient for inner nuclear membrane retention; the transmembrane segments with the C-terminal domain alone are not targeted to the INM. FRAP of GFP-MAN1 shows the fusion protein is relatively immobile in the nuclear envelope compared to the ER, consistent with binding to a nuclear component (diffusion-retention model).\",\n      \"method\": \"Confocal immunofluorescence of truncation mutants expressed in transfected cells; FRAP\",\n      \"journal\": \"Journal of cell science\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — multiple truncation constructs, FRAP with functional interpretation, single lab but two orthogonal methods\",\n      \"pmids\": [\"11896184\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2003,\n      \"finding\": \"C. elegans Ce-MAN1 binds directly to Ce-lamin and Ce-BAF in vitro, and requires Ce-lamin for its nuclear envelope localization. Ce-MAN1 has overlapping essential functions with Ce-emerin: combined RNAi depletion of both causes lethal anaphase chromosome bridging and cytokinesis failure (cut phenotype) with retention of phospho-histone H3 on bridged chromatin and failure to recruit lamin or BAF.\",\n      \"method\": \"In vitro direct binding assays, RNAi epistasis in C. elegans, immunostaining of mitotic cells\",\n      \"journal\": \"Proceedings of the National Academy of Sciences of the United States of America\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 / Moderate — in vitro direct binding plus genetic epistasis with clear cellular phenotype, single lab but multiple orthogonal methods\",\n      \"pmids\": [\"12684533\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2004,\n      \"finding\": \"LEMD3/MAN1 is mutated (heterozygous loss-of-function) in osteopoikilosis, Buschke-Ollendorff syndrome, and melorheostosis. LEMD3 interacts with BMP and activin/TGF-β receptor-activated Smads and antagonizes both signaling pathways in human cells.\",\n      \"method\": \"Genome-wide linkage analysis, mutation identification in patients, cell-based reporter assays for BMP/TGF-β signaling, protein interaction (co-immunoprecipitation)\",\n      \"journal\": \"Nature genetics\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — genetic mapping plus functional cell-based assays, independently replicated by multiple subsequent labs\",\n      \"pmids\": [\"15489854\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2004,\n      \"finding\": \"The C-terminal nucleoplasmic domain of human MAN1 directly binds Smad2 and Smad3 (but not the N-terminal domain) via yeast two-hybrid and GST pull-down under stringent conditions; antibodies against MAN1 co-immunoprecipitate Smad2 from cells. Overexpression of MAN1 or its C-terminal domain inhibits TGF-β-induced transcriptional reporter activation and TGF-β-induced cell proliferation arrest.\",\n      \"method\": \"Yeast two-hybrid, GST pull-down, co-immunoprecipitation, transcriptional reporter assays, stable cell line overexpression with proliferation assay\",\n      \"journal\": \"Human molecular genetics\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 / Strong — multiple orthogonal binding assays plus functional readouts, independently replicated across labs\",\n      \"pmids\": [\"15601644\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2005,\n      \"finding\": \"MAN1 associates with R-Smads (but not Smad4) at the inner nuclear membrane via its RNA recognition motif (RRM) domain in a ligand-independent manner. Overexpression of MAN1 inhibits R-Smad phosphorylation, heterodimerization with Smad4, and nuclear translocation, repressing TGF-β, BMP2, and activin-responsive promoters. A point mutation disrupting MAN1-Smad interaction abolishes transcriptional repression.\",\n      \"method\": \"Co-immunoprecipitation, reporter gene assays, phosphorylation assays, domain mapping, point mutagenesis\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 / Strong — mutagenesis-validated interaction with multiple functional readouts, independent from PMID 15601644\",\n      \"pmids\": [\"15647271\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2005,\n      \"finding\": \"The N-terminal domain of MAN1 (MAN1-N, containing the LEM domain) binds directly to BAF, lamin A, lamin B1, and directly to emerin in blot overlay and co-immunoprecipitation assays. The C-terminal domain (MAN1-C) binds the transcription regulators GCL, Btf, and BAF through a non-LEM BAF-binding motif (Ser-Arg-Val sequence).\",\n      \"method\": \"Blot overlay assays, co-immunoprecipitation, sequence alignment identifying conserved BAF-binding motif\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reciprocal binding assays with multiple fragments, single lab, two orthogonal methods\",\n      \"pmids\": [\"15681850\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2006,\n      \"finding\": \"The C-terminal nucleoplasmic region of MAN1 adopts a winged helix domain fold (determined by NMR) that binds DNA through its positively charged recognition helix H3. Structural modeling indicates that DNA-binding and R-Smad-binding surfaces are largely distinct, suggesting simultaneous binding to both DNA and R-Smads is possible.\",\n      \"method\": \"NMR structural characterization, DNA binding assays\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — NMR structure with functional DNA-binding validation, single lab but Tier 1 method\",\n      \"pmids\": [\"16648637\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2006,\n      \"finding\": \"Man1-deficient mouse embryos (lacking the Smad-interacting domain) die at mid-gestation due to defects in vascular remodeling. The primary capillary plexus forms but remodeling is perturbed, correlated with upregulated Tgfb1 expression, abnormally activated Smad2/3 signaling, increased extracellular matrix deposition, and disturbed mural cell recruitment.\",\n      \"method\": \"Conditional knockout mouse model, in situ hybridization, immunostaining, embryo phenotyping\",\n      \"journal\": \"Development (Cambridge, England)\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — defined loss-of-function with molecular phenotype (Smad2/3 activation, ECM deposition) linked to vascular remodeling defect\",\n      \"pmids\": [\"16943282\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2007,\n      \"finding\": \"MAN1 gene-trap homozygous (Man1GT/GT) mouse embryos die by E10.5 due to abnormal yolk-sac vascularization. MAN1GT/GT embryonic stem cells and their derivatives show increased phosphorylation and nuclear localization of SMAD2/3 and elevated SMAD transcriptional activity, predominantly from the ALK5 pathway.\",\n      \"method\": \"Gene-trap mouse model, tetraploid rescue experiments, embryonic stem cell differentiation, phospho-Smad immunostaining, transcriptional reporter assays\",\n      \"journal\": \"Development (Cambridge, England)\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — knockout with molecular readout (phospho-Smad), tetraploid rescue confirms yolk-sac origin, corroborates PMID 16943282\",\n      \"pmids\": [\"17329363\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2008,\n      \"finding\": \"Drosophila MAN1 (dMAN1) associates with receptor-regulated Smads (Mad), lamins, and the LEM-domain protein Bocksbeutel by yeast two-hybrid. Null dMAN1 mutants show decreased viability, male sterility, wing patterning defects, and increased phospho-Smad staining in wing discs, consistent with a role in TGF-β/BMP signaling in vivo.\",\n      \"method\": \"Yeast two-hybrid, P-element-generated null alleles, immunostaining of wing discs, genetic phenotype analysis\",\n      \"journal\": \"Genetics\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — yeast two-hybrid interaction plus loss-of-function phenotype with molecular marker (phospho-Smad), single lab\",\n      \"pmids\": [\"18723885\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2008,\n      \"finding\": \"Man1-deficient mouse embryos exhibit bilateral expression of Nodal, Lefty2, and Pitx2 in the lateral plate mesoderm (left-right axis defects), with normal midline Lefty1. Genetic crosses with Nodal hypomorphs show that bilateral Nodal expression in Man1-deficient embryos is node-independent, indicating Man1 regulates left-right asymmetry by controlling Nodal/Smad signaling outside the node.\",\n      \"method\": \"Mouse genetic epistasis (double mutant Man1Δ/Δ; Nodalneo/neo), in situ hybridization of laterality markers\",\n      \"journal\": \"Developmental dynamics\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genetic epistasis with clear molecular marker readout, single lab\",\n      \"pmids\": [\"18697220\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"MAN1 is phosphorylated in a cell cycle-dependent manner in the Xenopus egg cell-free system. M-phase-specific phosphorylation sites Thr-209, Ser-351, and Ser-402 were identified by MS/MS. Phosphorylation at Ser-402 (tested by S402A and S402E mutants) suppresses MAN1 binding to BAF during mitosis.\",\n      \"method\": \"Xenopus egg cell-free system, Titansphere column chromatography, MS/MS sequencing, in vitro BAF binding assay with phosphomimetic mutants\",\n      \"journal\": \"Biochemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — in vitro phosphorylation mapping plus mutagenesis validation of functional consequence, single lab\",\n      \"pmids\": [\"19166343\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"Drosophila MAN1 (MAN1ΔC mutants lacking the C-terminal RRM/Mad-binding domain) show wing crossvein patterning defects with expanded phospho-Mad accumulation and ectopic cv-2 expression in pupal wings, and a presynaptic role at the neuromuscular junction. MAN1 overexpression in wing discs inhibits crossvein development and BMP signaling. Genetic interaction experiments confirm MAN1 is a BMP signaling antagonist at the NMJ and during CV formation.\",\n      \"method\": \"Targeted mutagenesis (MAN1ΔC), immunostaining for phospho-Mad, in situ hybridization, electrophysiology, genetic interaction\",\n      \"journal\": \"Developmental biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 / Moderate — domain-deletion mutagenesis combined with molecular markers and genetic epistasis, single lab but multiple orthogonal methods\",\n      \"pmids\": [\"20036230\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"The C-terminal region of MAN1 that binds Smad2 comprises a winged helix domain, a linker, a U2AF homology motif (UHM) domain, and a disordered C-terminus. The linker acts as an intramolecular UHM ligand motif (ULM) interacting with the UHM domain; this intramolecular UHM-ULM interaction is critical for Smad2 binding (micromolar affinity). Mapping by GST pull-down, fluorescence, and yeast two-hybrid defined the linker, UHM domain, and C-terminus as the Smad2 binding interface.\",\n      \"method\": \"NMR spectroscopy, small-angle X-ray scattering (SAXS), GST pull-down, fluorescence binding assay, yeast two-hybrid\",\n      \"journal\": \"Biochemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — NMR + SAXS structural characterization combined with multiple binding assays, single lab, Tier 1 methods\",\n      \"pmids\": [\"20715792\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"BAF does not directly interact with MAN1-C in the absence of DNA; the previously reported interaction is an indirect association mediated by DNA binding and is not biologically relevant as a direct protein-protein interaction.\",\n      \"method\": \"In vitro binding assays under DNA-free conditions\",\n      \"journal\": \"PloS one\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — explicit negative result under controlled DNA-free conditions, challenges prior claim; single lab\",\n      \"pmids\": [\"21966431\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"3D structure of the MAN1 C-terminal region bound to Smad2 was modeled from NMR and SAXS data. MAN1 competes with the transcription factor FAST1 for Smad2 binding in vitro and in cells. MAN1 can bind activated Smad2-Smad4 and Smad3-Smad4 complexes in vitro but in cells binds only Smad2/3 not Smad4-containing complexes. MAN1 overexpression leads to Smad2/3 dephosphorylation; MAN1 binds directly in vitro to the phosphatase PPM1A, which dephosphorylates Smad2/3.\",\n      \"method\": \"NMR, SAXS, co-immunoprecipitation, in vitro competition assays, in vitro direct binding (MAN1-PPM1A), phospho-Smad western blotting\",\n      \"journal\": \"Science signaling\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — structural modeling with NMR/SAXS, multiple orthogonal biochemical validations, identification of phosphatase partner PPM1A, single lab but rigorous multi-method study\",\n      \"pmids\": [\"23779087\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"MAN1 directly binds the BMAL1 promoter and positively modulates BMAL1 transcription, establishing a connection between the inner nuclear membrane and circadian clock regulation.\",\n      \"method\": \"Chromatin immunoprecipitation (ChIP), transcriptional reporter assays, MAN1 knockdown/overexpression with BMAL1 expression readout\",\n      \"journal\": \"eLife\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — ChIP demonstrating direct promoter binding plus functional transcriptional readout, single lab\",\n      \"pmids\": [\"25182847\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"In Drosophila, loss of MAN1 causes synaptic overgrowth at neuromuscular junctions sensitive to BMP signaling levels; genetic removal of key BMP components attenuates BMP-induced synaptic overgrowth in MAN1 mutants. MAN1 negatively regulates accumulation and distribution of BMP signaling components at synapses.\",\n      \"method\": \"Drosophila genetics (null mutants, BMP pathway double mutants), electron microscopy of synapse ultrastructure, immunostaining\",\n      \"journal\": \"Cellular and molecular neurobiology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genetic epistasis with BMP pathway components, morphological phenotyping, single lab\",\n      \"pmids\": [\"27848060\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"MAN1 knockdown in mesenchymal stem cells (MSCs) increases osteogenesis and mineralization and decreases adipogenesis, associated with increased nuclear accumulation of regulatory Smads and Smad-related complexes and elevated nuclear β-Catenin. MAN1 overexpression primarily decreases adipogenesis without affecting osteogenesis.\",\n      \"method\": \"siRNA knockdown and overexpression in MSCs, osteogenic/adipogenic differentiation assays, immunostaining for nuclear Smad and β-Catenin\",\n      \"journal\": \"Journal of cellular biochemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Weak — loss/gain of function with cellular differentiation phenotype and molecular readout, single lab, single set of methods\",\n      \"pmids\": [\"28449239\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"Crystal structures of SMAD2-MAN1 and SMAD1-MAN1 complexes show that the intramolecular UHM-ULM interaction of MAN1 creates a hydrophobic surface that contacts the H2 helix, β8/β9 strands, and L3 loop of the MH2 domain of R-SMAD proteins. This surface is the conserved mechanism by which SMAD cofactors distinguish R-SMADs from Smad4.\",\n      \"method\": \"X-ray crystallography of SMAD2-MAN1 and SMAD1-MAN1 complexes\",\n      \"journal\": \"Nucleic acids research\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — crystal structures of two independent R-SMAD–MAN1 complexes, defining atomic basis of recognition, single lab but Tier 1 method\",\n      \"pmids\": [\"30321401\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"MAN1 knockdown in Drosophila pacemaker neurons lengthens locomotor rhythm period; molecular analysis shows reduced mRNA and protein levels of core clock gene period (per). Overexpression of per rescues the long-period phenotype, and per mutation is epistatic to MAN1 knockdown, indicating MAN1 sets circadian pace by targeting per transcription.\",\n      \"method\": \"Neuron-specific RNAi knockdown in Drosophila, RT-PCR, western blotting, genetic epistasis (per mutant × MAN1 RNAi), behavioral (locomotor) assay\",\n      \"journal\": \"Neuroscience bulletin\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — tissue-specific knockdown with molecular and behavioral readouts, genetic epistasis, single lab\",\n      \"pmids\": [\"31230212\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"Proximity biotinylation-based comparative interactome analysis of MAN1 identifies interactors enriched for ribonucleoprotein complex assembly components, suggesting a role for MAN1 in RNP complex assembly. MAN1 depletion (unlike LEM2 depletion) does not impair nucleotide excision repair.\",\n      \"method\": \"BioID proximity biotinylation mass spectrometry (comparative with emerin and LEM2), UV-C irradiation survival assay, γH2AX immunostaining\",\n      \"journal\": \"Cells\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — proximity proteomics with functional validation (negative for NER), single lab; RNP role is suggestive only\",\n      \"pmids\": [\"32085595\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"LEMD3 interacts with CBX3 (a reader of H3K9me2/3) to anchor heterochromatin at the nuclear periphery in vascular smooth muscle cells (VSMCs). Lemd3 deficiency disrupts 3D chromatin architecture (increased inter-TAD interactions at A/B compartment boundaries), decreases chromatin accessibility, and represses VSMC contractile gene expression, causing loss of the contractile phenotype and exacerbated intimal hyperplasia in mice.\",\n      \"method\": \"Genome-scale CRISPR screen, protein interactome analysis (Co-IP/MS), Hi-C (3D chromatin), ATAC-seq, RNA-seq, Lemd3 conditional knockout in mice\",\n      \"journal\": \"Nature communications\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 / Moderate — CRISPR screen followed by multi-omics validation (Hi-C, ATAC-seq, RNA-seq), protein interaction, and in vivo mouse phenotype, single lab but comprehensive multi-method study\",\n      \"pmids\": [\"41044070\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"MAN1 forms an inner nuclear membrane complex with the CTDNEP1-NEP1R1 phosphatase to mediate R-SMAD dephosphorylation and inactivation. Structural prediction, domain mapping, and mutagenesis show MAN1 has independent binding sites for CTDNEP1-NEP1R1 and R-SMADs. Disruption of this complex leads to nuclear accumulation of active R-SMADs and aberrant TGF-β signaling even without ligand. CTDNEP1-NEP1R1 is identified as the elusive R-SMAD phosphatase.\",\n      \"method\": \"Protein-protein interaction (domain mapping, mutagenesis), structural prediction, phospho-Smad assays, complex disruption experiments\",\n      \"journal\": \"bioRxiv\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1-2 / Moderate — domain mapping with mutagenesis plus functional phosphatase assays, preprint not yet peer-reviewed; identifies CTDNEP1-NEP1R1 as R-SMAD phosphatase in MAN1 complex\",\n      \"pmids\": [],\n      \"is_preprint\": true\n    }\n  ],\n  \"current_model\": \"LEMD3/MAN1 is an integral inner nuclear membrane protein retained at the INM via its N-terminal LEM domain (which also binds BAF, lamin A/B, and emerin), whose C-terminal winged helix–UHM domain directly binds R-Smad (Smad1/2/3) MH2 domains; at the INM it assembles a complex with the CTDNEP1-NEP1R1 phosphatase (and PPM1A) to promote R-Smad dephosphorylation and termination of TGF-β/BMP/activin signaling, while also anchoring H3K9me2/3-marked heterochromatin at the nuclear periphery via CBX3 to maintain cell-type-specific 3D chromatin architecture and gene expression, and cell-cycle-dependent phosphorylation of MAN1 (notably at Ser-402 by mitotic kinases) suppresses its BAF binding during mitosis.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"LEMD3/MAN1 is an integral inner nuclear membrane (INM) protein that serves as a membrane-tethered antagonist of TGF-\\u03b2/BMP/activin signaling and as an organizer of peripheral heterochromatin [#0, #3, #23]. It is anchored at the INM through its N-terminal nucleoplasmic LEM-domain region, which is necessary and sufficient for INM retention and binds directly to BAF, lamin A, lamin B1, and emerin, retaining MAN1 by a diffusion-retention mechanism [#1, #2, #6]. Its C-terminal nucleoplasmic tail folds into a winged-helix domain coupled to a U2AF homology motif (UHM) domain; an intramolecular UHM-ULM interaction creates the surface that directly engages the MH2 domain of receptor-activated Smads (Smad1/2/3) but not Smad4, the structural basis by which MAN1 discriminates R-Smads from the common mediator [#7, #14, #20]. By sequestering R-Smads at the nuclear envelope, MAN1 blocks their phosphorylation, heterodimerization with Smad4, and nuclear accumulation, and competes with the transcription factor FAST1 for Smad2, thereby repressing TGF-\\u03b2/BMP/activin-responsive transcription [#5, #16]. MAN1 promotes R-Smad dephosphorylation through direct association with phosphatase activity, binding PPM1A in vitro and assembling the CTDNEP1-NEP1R1 phosphatase complex at the INM via a binding site independent of its R-Smad site [#16, #24]. Loss-of-function studies across mouse, Drosophila, and C. elegans establish that MAN1 restrains Smad signaling in vivo: Man1-deficient mouse embryos die from vascular remodeling and yolk-sac vascularization defects with elevated phospho-Smad2/3, exhibit left-right axis defects via node-independent Nodal regulation, and Drosophila mutants show expanded phospho-Mad and BMP-dependent wing and synaptic phenotypes [#8, #9, #11, #13, #18]. MAN1 also anchors H3K9me2/3-marked heterochromatin at the nuclear periphery through CBX3, maintaining 3D chromatin architecture and contractile gene expression in vascular smooth muscle cells [#23]. Heterozygous loss-of-function mutations in LEMD3 cause osteopoikilosis, Buschke-Ollendorff syndrome, and melorheostosis [#3]. Beyond these themes, MAN1 has additional reported roles in circadian transcription and mitotic regulation, including direct binding to clock gene promoters and cell-cycle phosphorylation that suppresses BAF binding [#12, #17].\",\n  \"teleology\": [\n    {\n      \"year\": 2000,\n      \"claim\": \"Established LEMD3/MAN1 as a distinct LEM-domain inner nuclear membrane protein, defining its membrane topology and family membership before any function was known.\",\n      \"evidence\": \"Biochemical extraction, transfection/immunofluorescence, and sequence analysis identifying two TM segments, an N-terminal LEM domain, and a C-terminal nucleoplasmic tail\",\n      \"pmids\": [\"10671519\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"No binding partners identified\", \"No functional role established\"]\n    },\n    {\n      \"year\": 2002,\n      \"claim\": \"Defined how MAN1 is retained at the INM, showing the nucleoplasmic N-terminus is necessary and sufficient and that retention depends on binding an immobile nuclear component.\",\n      \"evidence\": \"Truncation-mutant immunofluorescence and FRAP of GFP-MAN1 in transfected cells\",\n      \"pmids\": [\"11896184\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Identity of the retained-on nuclear binding partner not defined in this study\"]\n    },\n    {\n      \"year\": 2003,\n      \"claim\": \"Identified the nuclear envelope anchoring partners and an essential mitotic function by showing MAN1 binds lamin and BAF and shares roles with emerin in chromosome segregation.\",\n      \"evidence\": \"In vitro direct binding assays and RNAi epistasis in C. elegans with mitotic immunostaining\",\n      \"pmids\": [\"12684533\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Mechanism of mitotic chromatin bridging not resolved\", \"Conservation to human function inferred from ortholog\"]\n    },\n    {\n      \"year\": 2004,\n      \"claim\": \"Connected LEMD3 to human disease and to TGF-\\u03b2/BMP signaling, identifying it as a Smad-interacting antagonist of both pathways and the gene mutated in sclerosing bone dysplasias.\",\n      \"evidence\": \"Linkage analysis and mutation identification in patients, cell-based BMP/TGF-\\u03b2 reporters, co-immunoprecipitation; yeast two-hybrid, GST pull-down, and reporter/proliferation assays mapping the C-terminal Smad2/3 interface\",\n      \"pmids\": [\"15489854\", \"15601644\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Mechanism of Smad inhibition not yet defined\", \"Structural basis of R-Smad selectivity unknown\"]\n    },\n    {\n      \"year\": 2005,\n      \"claim\": \"Resolved the mechanism of Smad repression and the bipartite domain organization, showing MAN1 sequesters R-Smads (not Smad4) at the INM to block phosphorylation, heterodimerization, and nuclear translocation, while the N-terminus binds lamins/BAF/emerin.\",\n      \"evidence\": \"Co-IP, domain mapping, point mutagenesis, phosphorylation and reporter assays; blot overlay and co-IP defining N- and C-terminal partner binding\",\n      \"pmids\": [\"15647271\", \"15681850\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"How MAN1 promotes loss of R-Smad phosphorylation not established\", \"Some C-terminal BAF binding later reinterpreted as DNA-mediated\"]\n    },\n    {\n      \"year\": 2006,\n      \"claim\": \"Provided the first structural insight and demonstrated the in vivo developmental requirement, showing the C-terminus is a DNA-binding winged-helix domain and that Man1 loss causes embryonic vascular defects with hyperactive Smad2/3.\",\n      \"evidence\": \"NMR structure with DNA-binding assays; conditional knockout mouse embryo phenotyping with in situ hybridization and immunostaining\",\n      \"pmids\": [\"16648637\", \"16943282\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Functional role of DNA binding in vivo unclear\", \"Direct phosphatase mechanism not yet identified\"]\n    },\n    {\n      \"year\": 2007,\n      \"claim\": \"Confirmed the vascular/Smad phenotype with an independent allele and tetraploid rescue, localizing the lethality to yolk-sac vascularization and elevated ALK5-driven SMAD2/3 activity.\",\n      \"evidence\": \"Gene-trap mouse, tetraploid rescue, ES-cell differentiation, phospho-Smad immunostaining and reporters\",\n      \"pmids\": [\"17329363\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Tissue-autonomous versus systemic contributions not fully separated\"]\n    },\n    {\n      \"year\": 2008,\n      \"claim\": \"Extended the Smad-antagonist role to additional in vivo contexts, demonstrating conserved Drosophila BMP/TGF-\\u03b2 antagonism and a node-independent role in regulating Nodal/Smad-driven left-right asymmetry.\",\n      \"evidence\": \"Drosophila yeast two-hybrid and null-allele phenotyping with phospho-Smad staining; mouse genetic epistasis with Nodal hypomorphs and laterality marker in situ hybridization\",\n      \"pmids\": [\"18723885\", \"18697220\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct biochemical mechanism of Nodal regulation not addressed\", \"Single-lab genetic interactions\"]\n    },\n    {\n      \"year\": 2009,\n      \"claim\": \"Identified cell-cycle regulation of MAN1 and refined its BMP-antagonist function, mapping mitotic phosphosites that suppress BAF binding and showing domain-specific BMP antagonism at the synapse and wing crossvein.\",\n      \"evidence\": \"Xenopus egg cell-free phosphosite mapping by MS/MS with phosphomimetic BAF-binding assays; Drosophila MAN1\\u0394C mutagenesis with phospho-Mad staining, electrophysiology, and genetic interaction\",\n      \"pmids\": [\"19166343\", \"20036230\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Kinases responsible for mitotic phosphorylation not identified\", \"In vivo consequence of phospho-regulation untested\"]\n    },\n    {\n      \"year\": 2010,\n      \"claim\": \"Elucidated the molecular architecture of Smad binding, showing an intramolecular UHM-ULM interaction within the C-terminal region is required for Smad2 engagement.\",\n      \"evidence\": \"NMR, SAXS, GST pull-down, fluorescence binding, and yeast two-hybrid mapping of the linker-UHM-C-terminus interface\",\n      \"pmids\": [\"20715792\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Atomic detail of the MAN1-R-Smad contact not yet resolved\"]\n    },\n    {\n      \"year\": 2011,\n      \"claim\": \"Corrected the interaction map by showing the reported C-terminal MAN1-BAF interaction is DNA-mediated rather than a direct protein-protein contact.\",\n      \"evidence\": \"In vitro binding assays under DNA-free conditions\",\n      \"pmids\": [\"21966431\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Biological role, if any, of the DNA-bridged association not defined\", \"Single-lab negative result\"]\n    },\n    {\n      \"year\": 2013,\n      \"claim\": \"Built a 3D model of the MAN1-Smad2 complex and linked MAN1 to active dephosphorylation, showing it competes with FAST1 for Smad2 and binds the phosphatase PPM1A.\",\n      \"evidence\": \"NMR/SAXS modeling, co-IP, in vitro competition and direct MAN1-PPM1A binding, phospho-Smad western blotting\",\n      \"pmids\": [\"23779087\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Whether PPM1A is the principal physiological R-Smad phosphatase at the INM unresolved\", \"In-cell selectivity for R-Smad over Smad4 complexes differs from in vitro\"]\n    },\n    {\n      \"year\": 2014,\n      \"claim\": \"Linked the INM protein to transcriptional regulation of the circadian clock, showing MAN1 directly binds the BMAL1 promoter and modulates its expression.\",\n      \"evidence\": \"ChIP, transcriptional reporters, knockdown/overexpression with BMAL1 readout\",\n      \"pmids\": [\"25182847\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Mechanism connecting membrane localization to promoter binding unclear\", \"Single-lab finding\"]\n    },\n    {\n      \"year\": 2016,\n      \"claim\": \"Reinforced the synaptic BMP-antagonist role, showing MAN1 loss causes BMP-dependent synaptic overgrowth and that MAN1 limits BMP component accumulation at synapses.\",\n      \"evidence\": \"Drosophila genetics, BMP pathway double mutants, EM of synapse ultrastructure, immunostaining\",\n      \"pmids\": [\"27848060\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Molecular mechanism of synaptic BMP component regulation not defined\"]\n    },\n    {\n      \"year\": 2017,\n      \"claim\": \"Demonstrated a cell-fate consequence of MAN1 Smad regulation, showing knockdown shifts mesenchymal stem cells toward osteogenesis with increased nuclear Smad and \\u03b2-Catenin.\",\n      \"evidence\": \"siRNA knockdown/overexpression in MSCs with differentiation assays and nuclear marker immunostaining\",\n      \"pmids\": [\"28449239\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct versus indirect role in \\u03b2-Catenin regulation not established\", \"Single-lab, single method set\"]\n    },\n    {\n      \"year\": 2018,\n      \"claim\": \"Defined the atomic basis of R-Smad recognition, showing the UHM-ULM-generated hydrophobic surface contacts conserved MH2 elements to distinguish R-Smads from Smad4.\",\n      \"evidence\": \"X-ray crystallography of SMAD2-MAN1 and SMAD1-MAN1 complexes\",\n      \"pmids\": [\"30321401\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Structural context within the full-length INM-anchored protein not captured\"]\n    },\n    {\n      \"year\": 2019,\n      \"claim\": \"Confirmed a conserved circadian function in vivo, showing MAN1 knockdown in pacemaker neurons lengthens period by targeting period (per) transcription.\",\n      \"evidence\": \"Neuron-specific RNAi, RT-PCR, western blot, per genetic epistasis, locomotor behavior\",\n      \"pmids\": [\"31230212\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct promoter binding to per not shown\", \"Relationship to mammalian BMAL1 regulation unclear\"]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"Mapped the MAN1 proximity interactome and distinguished it from other LEM proteins, identifying enrichment for ribonucleoprotein assembly components and ruling out a role in nucleotide excision repair.\",\n      \"evidence\": \"Comparative BioID mass spectrometry, UV-C survival, \\u03b3H2AX immunostaining\",\n      \"pmids\": [\"32085595\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Functional role in RNP assembly only suggestive\", \"No validated RNP partner characterized\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Established a chromatin-organizing function, showing LEMD3 anchors H3K9me2/3 heterochromatin at the nuclear periphery via CBX3 to maintain 3D genome architecture and the VSMC contractile phenotype.\",\n      \"evidence\": \"CRISPR screen, Co-IP/MS, Hi-C, ATAC-seq, RNA-seq, and conditional knockout mice\",\n      \"pmids\": [\"41044070\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"How CBX3 tethering integrates with Smad-antagonist function unresolved\", \"Generalizability beyond VSMCs untested\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Identified the long-sought R-Smad phosphatase recruited by MAN1, showing it assembles CTDNEP1-NEP1R1 at the INM via a binding site separate from its R-Smad site to drive R-Smad dephosphorylation.\",\n      \"evidence\": \"Domain mapping, mutagenesis, structural prediction, phospho-Smad and complex-disruption assays (preprint)\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Not yet peer-reviewed\", \"Relationship to earlier PPM1A finding not reconciled\", \"No structure of the assembled INM complex\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How MAN1's two principal activities\\u2014membrane-tethered R-Smad termination and CBX3-mediated heterochromatin anchoring\\u2014are coordinated, and how each contributes to the distinct LEMD3 disease phenotypes, remains unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Low\",\n      \"gaps\": [\"No integrated model linking Smad and chromatin functions\", \"Tissue-specific basis of osteopoikilosis/melorheostosis not mechanistically explained\", \"Phosphatase identity (PPM1A vs CTDNEP1-NEP1R1) not reconciled\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0003677\", \"supporting_discovery_ids\": [7]},\n      {\"term_id\": \"GO:0098772\", \"supporting_discovery_ids\": [4, 5, 16, 24]},\n      {\"term_id\": \"GO:0140110\", \"supporting_discovery_ids\": [17, 23]},\n      {\"term_id\": \"GO:0042393\", \"supporting_discovery_ids\": [23]},\n      {\"term_id\": \"GO:0060090\", \"supporting_discovery_ids\": [16, 24]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005635\", \"supporting_discovery_ids\": [0, 1, 2]},\n      {\"term_id\": \"GO:0005634\", \"supporting_discovery_ids\": [0]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-162582\", \"supporting_discovery_ids\": [3, 4, 5, 16]},\n      {\"term_id\": \"R-HSA-4839726\", \"supporting_discovery_ids\": [23]},\n      {\"term_id\": \"R-HSA-74160\", \"supporting_discovery_ids\": [17, 23]},\n      {\"term_id\": \"R-HSA-1266738\", \"supporting_discovery_ids\": [8, 9, 11, 13]},\n      {\"term_id\": \"R-HSA-9909396\", \"supporting_discovery_ids\": [17, 21]}\n    ],\n    \"complexes\": [\n      \"CTDNEP1-NEP1R1 phosphatase complex (INM)\"\n    ],\n    \"partners\": [\n      \"SMAD2\",\n      \"SMAD3\",\n      \"SMAD1\",\n      \"BAF/BANF1\",\n      \"LMNA\",\n      \"EMD\",\n      \"PPM1A\",\n      \"CBX3\"\n    ],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":9,"faith_total":9,"faith_pct":100.0}}