{"gene":"PEX2","run_date":"2026-06-10T05:19:53","timeline":{"discoveries":[{"year":2009,"finding":"PEX2 (along with PEX10 and PEX12) functions as a RING-domain E3 ubiquitin-protein isopeptide ligase in peroxisomal matrix protein import. Specifically, PEX2 mediates Ubc4-dependent polyubiquitination of the import receptor Pex5, targeting it for proteasomal degradation, while PEX12 mediates Pex4-dependent monoubiquitination of Pex5 for receptor recycling.","method":"In vitro ubiquitin ligase activity assays, RING domain functional analysis, identification of cognate E2 enzymes (Ubc4 vs Pex4) for each RING peroxin","journal":"Molecular and cellular biology","confidence":"High","confidence_rationale":"Tier 1 / Strong — in vitro ubiquitin ligase assay with defined E2 partners and specific substrates, replicated across multiple RING peroxins in same study","pmids":["19687296"],"is_preprint":false},{"year":2016,"finding":"Mammalian PEX2 is the E3 ubiquitin ligase responsible for pexophagy: its expression causes gross ubiquitination of peroxisomes and their degradation via an NBR1-dependent autophagic process. PEX5 and PMP70 are identified as direct substrates ubiquitinated by PEX2 during amino acid starvation. PEX2 expression is upregulated during amino acid starvation and rapamycin treatment, indicating that mTORC1 pathway controls pexophagy by regulating PEX2 levels.","method":"PEX2 overexpression with ubiquitination assays, NBR1 knockdown rescue experiments, substrate identification (PEX5 and PMP70), mTOR pathway inhibitor treatment, in vivo animal model validation","journal":"The Journal of cell biology","confidence":"High","confidence_rationale":"Tier 2 / Strong — multiple orthogonal methods (ubiquitination assay, substrate identification, pathway manipulation, in vivo validation), published in high-impact journal","pmids":["27597759"],"is_preprint":false},{"year":1997,"finding":"Targeted deletion of PEX2 in mice abolishes functional peroxisome assembly (leaving only empty membrane ghosts), causes accumulation of very long chain fatty acids, deficient plasmalogens, disordered neuronal migration in cerebral cortex, and neonatal lethality, establishing PEX2 as essential for peroxisomal biogenesis and function in vivo.","method":"Gene targeting/knockout in mice, biochemical analysis (VLCFA, plasmalogens), immunohistochemistry, neuroanatomical analysis","journal":"The Journal of cell biology","confidence":"High","confidence_rationale":"Tier 2 / Strong — clean knockout with defined biochemical and cellular phenotypes, replicated in multiple subsequent studies","pmids":["9382874"],"is_preprint":false},{"year":2000,"finding":"A missense mutation changing cysteine-258 to tyrosine in the RING finger motif of PEX2 selectively abolishes PTS1-dependent peroxisomal protein import while leaving PTS2-dependent import (e.g., 3-ketoacyl-CoA thiolase) intact, demonstrating that the RING finger domain is specifically required for the PTS1 import pathway.","method":"Site-directed mutagenesis of RING finger domain, immunocytochemical localization of PTS1 and PTS2 cargo proteins in CHO mutant cells and stable transformants with wild-type or mutant PEX2 cDNA","journal":"Biochemical and biophysical research communications","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — active-site mutagenesis with functional readout in cell-based assay, rescue experiments, single lab","pmids":["10772890"],"is_preprint":false},{"year":2003,"finding":"The minimum peroxisomal membrane targeting signal of human PEX2 consists of an internal 30 amino acid region (AA130–159) plus the first transmembrane domain; the targeting motif 'KX6(I/L)X(L/F/I)LK(L/F/I)' within this region is essential, and mutations in it mislocalize PEX2 to the cytosol. The second transmembrane domain increases targeting efficiency but does not contain specific targeting information.","method":"GFP-fusion deletion constructs expressed in COS-7 cells with intracellular localization determination; motif mutagenesis; chimeric construct with heterologous transmembrane domain","journal":"European journal of cell biology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — systematic deletion and mutagenesis analysis in cell-based assay, single lab, multiple constructs tested","pmids":["12751901"],"is_preprint":false},{"year":1998,"finding":"Overexpression of PMP70 (a 70 kDa peroxisomal membrane protein) suppresses the peroxisome biogenesis defect caused by PEX2 mutations in CHO cells, restoring catalase latency, catalase localization, and VLCFA beta-oxidation, suggesting a functional interaction between PEX2 and PMP70 in the peroxisome membrane. A disease-causing mutant allele of PMP70 did not rescue, confirming specificity.","method":"Expression of PMP70 in PEX2-deficient CHO cell clones, subcellular catalase latency assay, immunohistochemical localization of catalase, VLCFA beta-oxidation assay","journal":"European journal of cell biology","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — functional rescue assay with multiple readouts, mutant PMP70 control, single lab","pmids":["9765053"],"is_preprint":false},{"year":2000,"finding":"PEX2 encodes a 35-kDa peroxisomal membrane protein with two membrane-spanning domains and a C-terminal RING finger motif exposed to the cytosol. Mutations truncating the protein and removing both transmembrane domains and the RING domain cause severe disease, while a mutation disrupting only the C-terminal RING finger domain (del642G) causes milder phenotype with residual peroxisome assembly, demonstrating that the transmembrane domains are critical for peroxisome assembly and the C-terminal RING finger domain modulates import efficiency.","method":"Patient mutation characterization, expression of mutated PEX2 in PEX2-deficient CHO cells, immunocytochemistry for catalase-containing peroxisomes","journal":"Biochemical and biophysical research communications","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — domain function assigned via patient mutations and cell complementation assay, single lab","pmids":["10652207"],"is_preprint":false},{"year":2002,"finding":"PEX2 functions in the peroxisomal RING-finger complex downstream of both PEX5 (PTS1 receptor) and PEX7 (PTS2 receptor), making it required for import of both PTS1 and PTS2 proteins. Genetic epistasis in Podospora anserina shows that pex2 deletion causes both metabolic (oleic acid growth) and developmental (meiotic commitment) defects, and that PEX2 has functions beyond those of the PTS1/PTS2 receptors.","method":"Genetic epistasis analysis in Podospora anserina (single and double knockouts of pex2, pex5, pex7), immunofluorescence and GFP staining for peroxisome biogenesis, growth assays","journal":"Molecular microbiology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — genetic epistasis with multiple mutant combinations and orthogonal readouts, single organism/lab","pmids":["16987176"],"is_preprint":false},{"year":2002,"finding":"PEX2 protein functions differentially in two steps of thiolase (PTS2 cargo) maturation: its RING finger domain (Cys258) is required for the final maturation/processing step of thiolase precursor, while a distinct domain supports initial peroxisomal docking/association of the precursor. CHO cells with Pex2pC258Y mutation accumulate thiolase precursor in peroxisomes rather than excluding it to cytosol, in contrast to complete truncation mutants.","method":"SDS-PAGE analysis of thiolase precursor form, salt wash, sodium carbonate extraction, proteinase K protection assay, differential digitonin permeabilization with immunofluorescence in five PEX2 CHO mutant cell lines","journal":"Biochimica et biophysica acta","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — multiple biochemical methods (membrane association, protease protection, size analysis) across multiple defined mutant cell lines, single lab","pmids":["12031794"],"is_preprint":false},{"year":2002,"finding":"A novel PEX2 point mutation (Arg50 nonsense) in CHO cells produces a unique phenotype: defective catalase import but temperature-sensitive PTS1 and PTS2 import (normal at 37°C, abrogated at 39°C), demonstrating that catalase import and general PTS1/PTS2 import are mechanistically separable functions of PEX2.","method":"Mutagenesis screen in CHO cells, temperature-shift experiments, immunolocalization of catalase and PTS1/PTS2 cargo proteins, sequencing of PEX2 mutation","journal":"Biochemical and biophysical research communications","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — temperature-sensitive allele with clear separation of import activities, single lab","pmids":["12054689"],"is_preprint":false},{"year":1996,"finding":"The Pichia pastoris PER6 gene product (Per6p), a homolog of human PAF-1/PEX2, is a peroxisomal integral membrane protein with a C3HC4 RING motif; loss of PER6 causes absence of morphologically recognizable peroxisomes and cytosolic mislocalization of peroxisomal matrix proteins, establishing the conserved role of this peroxin family in peroxisome biogenesis. Per6p is correctly targeted to mammalian peroxisomes, demonstrating evolutionary conservation of targeting.","method":"Gene cloning and functional complementation, immunolocalization, fractionation, cross-species targeting experiment (Per6p expressed in mammalian cells)","journal":"Molecular and cellular biology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — loss-of-function phenotype plus heterologous targeting experiment, ortholog data consistent with mammalian PEX2 function","pmids":["8628321"],"is_preprint":false},{"year":2025,"finding":"In yeast, the Pex2/Pex10/Pex12 E3-ubiquitin ligase complex assembles with the Pex5/Pex8 complex to initiate receptor recycling after cargo release into peroxisomes, as supported by structural and functional evidence showing that Pex8 interaction with Pex5 N-terminal domain is required for peroxisomal protein translocation and enables downstream assembly with the RING E3 complex.","method":"Cryo-EM/structural analysis of Pex8-Pex5 complex, functional translocation assays, mutagenesis of interaction interface","journal":"bioRxiv","confidence":"Medium","confidence_rationale":"Tier 1 / Moderate — structural data plus mutagenesis in yeast ortholog system, preprint not yet peer-reviewed, places PEX2 complex in receptor recycling pathway","pmids":["bio_10.1101_2025.08.30.673231"],"is_preprint":true}],"current_model":"PEX2 is a peroxisomal integral membrane protein containing two transmembrane domains and a cytoplasmic C3HC4 RING finger domain that functions as an E3 ubiquitin ligase: it mediates Ubc4-dependent polyubiquitination of the import receptor PEX5 to trigger its proteasomal degradation during normal import receptor recycling, and during nutrient starvation it ubiquitinates PEX5 and PMP70 to signal pexophagy via an NBR1-dependent autophagic pathway; the RING domain is also required for PTS1-dependent matrix protein import, while the transmembrane domains are essential for peroxisome membrane assembly, and together the Pex2/Pex10/Pex12 RING complex acts downstream of cargo/receptor recognition to coordinate cargo translocation and receptor recycling."},"narrative":{"mechanistic_narrative":"PEX2 is a peroxisomal integral membrane protein essential for peroxisome biogenesis and matrix protein import, acting through a cytosol-exposed C3HC4 RING finger that confers E3 ubiquitin ligase activity [PMID:19687296, PMID:9382874]. Together with the RING peroxins PEX10 and PEX12, PEX2 mediates Ubc4-dependent polyubiquitination of the PTS1 import receptor PEX5, targeting it for proteasomal degradation as part of receptor recycling downstream of cargo recognition [PMID:19687296]. Structurally, the protein spans the membrane twice via two transmembrane domains that carry its membrane-targeting information and are critical for peroxisome assembly, while the RING domain modulates import efficiency [PMID:12751901, PMID:10652207]; a point mutation in the RING motif (Cys258) selectively abolishes PTS1-dependent import and blocks the final maturation step of PTS2 cargo such as thiolase, showing that distinct PEX2 functions govern docking, translocation, and receptor handling [PMID:10772890, PMID:12031794]. PEX2 also serves as the E3 ligase for pexophagy: under amino acid starvation it ubiquitinates PEX5 and PMP70 to drive NBR1-dependent autophagic degradation of peroxisomes, with its expression controlled by mTORC1 signaling [PMID:27597759]. Loss of PEX2 in mice abolishes functional peroxisome assembly, leaving only membrane ghosts, and causes very long chain fatty acid accumulation, plasmalogen deficiency, disordered neuronal migration, and neonatal lethality, and PEX2-truncating mutations cause severe peroxisome biogenesis disease in humans [PMID:9382874, PMID:10652207].","teleology":[{"year":1996,"claim":"Established that the PEX2 family is a conserved peroxisomal integral membrane protein with a RING motif required for peroxisome biogenesis, answering whether this peroxin is needed for organelle formation.","evidence":"Gene cloning, loss-of-function, fractionation, and cross-species targeting of the Pichia pastoris PER6/PEX2 homolog","pmids":["8628321"],"confidence":"Medium","gaps":["Did not define the biochemical activity of the RING motif","Ortholog-based; mammalian mechanism not directly tested"]},{"year":1997,"claim":"Demonstrated in vivo that PEX2 is essential for functional peroxisome assembly and for peroxisomal lipid metabolism and brain development, establishing physiological consequences of its loss.","evidence":"PEX2 knockout mice with VLCFA/plasmalogen biochemistry and neuroanatomical analysis","pmids":["9382874"],"confidence":"High","gaps":["Did not resolve the molecular step PEX2 performs in import","Mechanism linking assembly defect to neuronal migration unaddressed"]},{"year":2000,"claim":"Separated the functional contributions of the transmembrane region and the RING domain, showing transmembrane domains drive assembly while the RING finger tunes import efficiency.","evidence":"Patient mutation characterization and complementation in PEX2-deficient CHO cells","pmids":["10652207","10772890"],"confidence":"Medium","gaps":["Molecular activity of the RING domain not yet defined","How the RING domain affects import efficiency mechanistically unclear"]},{"year":2002,"claim":"Resolved that PEX2 acts downstream of both PTS1 and PTS2 receptors and contributes to multiple separable import steps, including thiolase maturation and a temperature-sensitive, catalase-specific import function.","evidence":"Genetic epistasis in Podospora anserina and biochemical/protease-protection analysis of multiple CHO PEX2 mutant alleles","pmids":["16987176","12031794","12054689"],"confidence":"Medium","gaps":["Did not identify the enzymatic mechanism distinguishing these steps","Single-organism/lab evidence for each separable function"]},{"year":2003,"claim":"Defined the peroxisomal membrane targeting signal of PEX2, answering how the protein reaches the peroxisome membrane.","evidence":"GFP-fusion deletion and motif mutagenesis in COS-7 cells","pmids":["12751901"],"confidence":"Medium","gaps":["Targeting machinery recognizing the motif not identified","Single lab, cell-based assay only"]},{"year":2009,"claim":"Identified PEX2 as a RING E3 ligase that polyubiquitinates PEX5 for proteasomal degradation via Ubc4, defining its molecular activity within the import/recycling cycle.","evidence":"In vitro ubiquitin ligase assays with defined E2 partners across the RING peroxins","pmids":["19687296"],"confidence":"High","gaps":["Did not define how E3 activity is regulated in vivo","Relationship to membrane assembly function not integrated"]},{"year":2016,"claim":"Showed PEX2 is the E3 ligase driving pexophagy, ubiquitinating PEX5 and PMP70 under starvation to trigger NBR1-dependent autophagy under mTORC1 control, extending its role from import recycling to organelle turnover.","evidence":"PEX2 overexpression ubiquitination assays, NBR1 knockdown rescue, substrate identification, mTOR inhibitor treatment, and in vivo validation","pmids":["27597759"],"confidence":"High","gaps":["How a single ligase switches between recycling and pexophagy substrates unresolved","Precise mTORC1-to-PEX2 transcriptional link not defined"]},{"year":2025,"claim":"Placed the Pex2/Pex10/Pex12 RING complex into the structural sequence of receptor recycling, showing it assembles with the Pex5/Pex8 complex after cargo release.","evidence":"Cryo-EM/structural analysis and translocation/mutagenesis assays in yeast (preprint)","pmids":["bio_10.1101_2025.08.30.673231"],"confidence":"Medium","gaps":["Preprint, not peer-reviewed","Yeast ortholog system; mammalian complex architecture not directly shown"]},{"year":null,"claim":"How PEX2 substrate choice and activity are switched between routine receptor recycling and starvation-induced pexophagy at the molecular level remains unresolved.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No mechanism defining recycling vs. pexophagy substrate selection","Structural basis of mammalian RING complex assembly not established"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0016874","term_label":"ligase activity","supporting_discovery_ids":[0,1]},{"term_id":"GO:0140096","term_label":"catalytic activity, acting on a protein","supporting_discovery_ids":[0,1]}],"localization":[],"pathway":[{"term_id":"R-HSA-9609507","term_label":"Protein localization","supporting_discovery_ids":[0,3,7]},{"term_id":"R-HSA-9612973","term_label":"Autophagy","supporting_discovery_ids":[1]},{"term_id":"R-HSA-1852241","term_label":"Organelle biogenesis and maintenance","supporting_discovery_ids":[2,10]}],"complexes":["Pex2/Pex10/Pex12 RING E3 ligase complex"],"partners":["PEX10","PEX12","PEX5","PMP70","NBR1","PEX7","PEX8"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"P28328","full_name":"Peroxisome biogenesis factor 2","aliases":["35 kDa peroxisomal membrane protein","Peroxin-2","Peroxisomal membrane protein 3","Peroxisome assembly factor 1","PAF-1","RING finger protein 72"],"length_aa":305,"mass_kda":34.8,"function":"E3 ubiquitin-protein ligase component of a retrotranslocation channel required for peroxisome organization by mediating export of the PEX5 receptor from peroxisomes to the cytosol, thereby promoting PEX5 recycling (PubMed:24662292). The retrotranslocation channel is composed of PEX2, PEX10 and PEX12; each subunit contributing transmembrane segments that coassemble into an open channel that specifically allows the passage of PEX5 through the peroxisomal membrane (By similarity). PEX2 also regulates peroxisome organization by acting as a E3 ubiquitin-protein ligase (By similarity). PEX2 ubiquitinates PEX5 during its passage through the retrotranslocation channel: catalyzes monoubiquitination of PEX5 at 'Cys-11', a modification that acts as a signal for PEX5 extraction into the cytosol (By similarity). Required for pexophagy in response to starvation by mediating ubiquitination of peroxisomal proteins, such as PEX5 and ABCD3/PMP70 (PubMed:27597759). Also involved in the response to reactive oxygen species (ROS) by mediating 'Lys-48'-linked polyubiquitination and subsequent degradation of PNPLA2/ATGL, thereby regulating lipolysis (PubMed:34903883)","subcellular_location":"Peroxisome membrane","url":"https://www.uniprot.org/uniprotkb/P28328/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/PEX2","classification":"Not Classified","n_dependent_lines":44,"n_total_lines":1208,"dependency_fraction":0.03642384105960265},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[],"url":"https://opencell.sf.czbiohub.org/search/PEX2","total_profiled":1310},"omim":[{"mim_id":"614885","title":"PEROXISOME BIOGENESIS DISORDER 11B; PBD11B","url":"https://www.omim.org/entry/614885"},{"mim_id":"614870","title":"PEROXISOME BIOGENESIS DISORDER 6A (ZELLWEGER); PBD6A","url":"https://www.omim.org/entry/614870"},{"mim_id":"614867","title":"PEROXISOME BIOGENESIS DISORDER 5B; PBD5B","url":"https://www.omim.org/entry/614867"},{"mim_id":"614866","title":"PEROXISOME BIOGENESIS DISORDER 5A (ZELLWEGER); PBD5A","url":"https://www.omim.org/entry/614866"},{"mim_id":"614230","title":"CHROMOSOME 8q21.11 DELETION SYNDROME","url":"https://www.omim.org/entry/614230"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Supported","locations":[{"location":"Vesicles","reliability":"Supported"},{"location":"Nucleoplasm","reliability":"Additional"}],"tissue_specificity":"Low tissue specificity","tissue_distribution":"Detected in all","driving_tissues":[],"url":"https://www.proteinatlas.org/search/PEX2"},"hgnc":{"alias_symbol":["PMP35","PAF-1","RNF72","ZWS3"],"prev_symbol":["PXMP3"]},"alphafold":{"accession":"P28328","domains":[{"cath_id":"-","chopping":"2-183","consensus_level":"high","plddt":86.0515,"start":2,"end":183},{"cath_id":"3.30.40.10","chopping":"241-296","consensus_level":"medium","plddt":80.3534,"start":241,"end":296}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/P28328","model_url":"https://alphafold.ebi.ac.uk/files/AF-P28328-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-P28328-F1-predicted_aligned_error_v6.png","plddt_mean":80.38},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=PEX2","jax_strain_url":"https://www.jax.org/strain/search?query=PEX2"},"sequence":{"accession":"P28328","fasta_url":"https://rest.uniprot.org/uniprotkb/P28328.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/P28328/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/P28328"}},"corpus_meta":[{"pmid":"19687296","id":"PMC_19687296","title":"Pex2 and pex12 function as protein-ubiquitin ligases in peroxisomal protein import.","date":"2009","source":"Molecular and cellular biology","url":"https://pubmed.ncbi.nlm.nih.gov/19687296","citation_count":164,"is_preprint":false},{"pmid":"27597759","id":"PMC_27597759","title":"PEX2 is the E3 ubiquitin ligase required for pexophagy during starvation.","date":"2016","source":"The Journal of cell biology","url":"https://pubmed.ncbi.nlm.nih.gov/27597759","citation_count":152,"is_preprint":false},{"pmid":"9382874","id":"PMC_9382874","title":"Targeted deletion of the PEX2 peroxisome assembly gene in mice provides a model for Zellweger syndrome, a human neuronal migration disorder.","date":"1997","source":"The Journal of cell biology","url":"https://pubmed.ncbi.nlm.nih.gov/9382874","citation_count":130,"is_preprint":false},{"pmid":"12746876","id":"PMC_12746876","title":"Abnormal cerebellar histogenesis in PEX2 Zellweger mice reflects multiple neuronal defects induced by peroxisome deficiency.","date":"2003","source":"The Journal of comparative neurology","url":"https://pubmed.ncbi.nlm.nih.gov/12746876","citation_count":59,"is_preprint":false},{"pmid":"17393522","id":"PMC_17393522","title":"Bile acid treatment alters hepatic disease and bile acid transport in peroxisome-deficient PEX2 Zellweger mice.","date":"2007","source":"Hepatology (Baltimore, Md.)","url":"https://pubmed.ncbi.nlm.nih.gov/17393522","citation_count":57,"is_preprint":false},{"pmid":"8628321","id":"PMC_8628321","title":"The Pichia pastoris PER6 gene product is a peroxisomal integral membrane protein essential for peroxisome biogenesis and has sequence similarity to the Zellweger syndrome protein PAF-1.","date":"1996","source":"Molecular and cellular biology","url":"https://pubmed.ncbi.nlm.nih.gov/8628321","citation_count":55,"is_preprint":false},{"pmid":"16987176","id":"PMC_16987176","title":"The peroxisomal import proteins PEX2, PEX5 and PEX7 are differently involved in Podospora anserina sexual 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MASLD by regulating liver ABCD2/PEX2/ATGL axis-mediated fatty acid metabolic reprogramming.","date":"2025","source":"Phytomedicine : international journal of phytotherapy and phytopharmacology","url":"https://pubmed.ncbi.nlm.nih.gov/40674914","citation_count":7,"is_preprint":false},{"pmid":"8043297","id":"PMC_8043297","title":"Structure and expression of mammalian peroxisome assembly factor-1 (PMP35) genes.","date":"1994","source":"Biochemical medicine and metabolic biology","url":"https://pubmed.ncbi.nlm.nih.gov/8043297","citation_count":7,"is_preprint":false},{"pmid":"12054689","id":"PMC_12054689","title":"A novel pex2 mutant: catalase-deficient but temperature-sensitive PTS1 and PTS2 import.","date":"2002","source":"Biochemical and biophysical research communications","url":"https://pubmed.ncbi.nlm.nih.gov/12054689","citation_count":7,"is_preprint":false},{"pmid":"10891359","id":"PMC_10891359","title":"Genomic organization and characterization of human PEX2 encoding a 35-kDa peroxisomal membrane protein.","date":"2000","source":"Biochemical and biophysical research communications","url":"https://pubmed.ncbi.nlm.nih.gov/10891359","citation_count":5,"is_preprint":false},{"pmid":"23590336","id":"PMC_23590336","title":"A deleterious mutation in the PEX2 gene causes Zellweger syndrome in individuals of Ashkenazi Jewish descent.","date":"2013","source":"Clinical genetics","url":"https://pubmed.ncbi.nlm.nih.gov/23590336","citation_count":5,"is_preprint":false},{"pmid":"12031794","id":"PMC_12031794","title":"Different accumulations of 3-ketoacyl-CoA thiolase precursor in peroxisomes of Chinese hamster ovary cells harboring a dysfunction in the PEX2 protein.","date":"2002","source":"Biochimica et biophysica acta","url":"https://pubmed.ncbi.nlm.nih.gov/12031794","citation_count":5,"is_preprint":false},{"pmid":"7512952","id":"PMC_7512952","title":"Genetic evidence supporting the role of peroxisome assembly factor (PAF)-1 in peroxisome biogenesis. Polymerase chain reaction detection of a missense mutation in PAF-1 of Chinese hamster ovary cells.","date":"1994","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/7512952","citation_count":3,"is_preprint":false},{"pmid":"9643362","id":"PMC_9643362","title":"Metabolic fate of platelet-activating factor (PAF, 1-O-alkyl-2-acetyl-sn-glycero-3-phosphocholine) and lyso-PAF (1-O-alkyl-2-lyso-sn-glycero-3-phosphocholine) in FRTL5 cells.","date":"1998","source":"Journal of lipid research","url":"https://pubmed.ncbi.nlm.nih.gov/9643362","citation_count":2,"is_preprint":false},{"pmid":"40621817","id":"PMC_40621817","title":"Distinguishing PEX2 and PEX16 gene variant severity for mild, severe and atypical peroxisome biogenesis disorders.","date":"2025","source":"Disease models & mechanisms","url":"https://pubmed.ncbi.nlm.nih.gov/40621817","citation_count":1,"is_preprint":false},{"pmid":"41815956","id":"PMC_41815956","title":"Dysregulated lipid metabolism and hypomyelination in postnatal peroxisome-deficient Pex2 knockout Zellweger mice.","date":"2026","source":"Frontiers in molecular neuroscience","url":"https://pubmed.ncbi.nlm.nih.gov/41815956","citation_count":0,"is_preprint":false},{"pmid":null,"id":"bio_10.1101_2025.08.30.673231","title":"Structure of Pex8 in complex with peroxisomal receptor Pex5 reveals its essential role in peroxisomal cargo translocation","date":"2025-09-02","source":"bioRxiv","url":"https://doi.org/10.1101/2025.08.30.673231","citation_count":0,"is_preprint":true},{"pmid":null,"id":"bio_10.1101_2024.11.14.623590","title":"Distinguishing  <i>PEX</i>  gene variant severity for mild, severe, and atypical peroxisome biogenesis disorders in  <i>Drosophila</i>","date":"2024-11-15","source":"bioRxiv","url":"https://doi.org/10.1101/2024.11.14.623590","citation_count":0,"is_preprint":true},{"pmid":null,"id":"bio_10.1101_2024.09.23.614586","title":"Genetic analysis of the X-linked Adrenoleukodystrophy  <i>ABCD1 gene</i>  in  <i>Drosophila</i>  uncovers a role in Peroxisomal dynamics","date":"2024-09-25","source":"bioRxiv","url":"https://doi.org/10.1101/2024.09.23.614586","citation_count":0,"is_preprint":true}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":19738,"output_tokens":3501,"usd":0.055864,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":11029,"output_tokens":2869,"usd":0.063435,"stage2_stop_reason":"end_turn"},"total_usd":0.119299,"stage1_batch_id":"msgbatch_013a8chtv3AWyTqv4z4sEF4C","stage2_batch_id":"msgbatch_01AHsuW63vinsvuTgzmQ3n62","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2009,\n      \"finding\": \"PEX2 (along with PEX10 and PEX12) functions as a RING-domain E3 ubiquitin-protein isopeptide ligase in peroxisomal matrix protein import. Specifically, PEX2 mediates Ubc4-dependent polyubiquitination of the import receptor Pex5, targeting it for proteasomal degradation, while PEX12 mediates Pex4-dependent monoubiquitination of Pex5 for receptor recycling.\",\n      \"method\": \"In vitro ubiquitin ligase activity assays, RING domain functional analysis, identification of cognate E2 enzymes (Ubc4 vs Pex4) for each RING peroxin\",\n      \"journal\": \"Molecular and cellular biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — in vitro ubiquitin ligase assay with defined E2 partners and specific substrates, replicated across multiple RING peroxins in same study\",\n      \"pmids\": [\"19687296\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"Mammalian PEX2 is the E3 ubiquitin ligase responsible for pexophagy: its expression causes gross ubiquitination of peroxisomes and their degradation via an NBR1-dependent autophagic process. PEX5 and PMP70 are identified as direct substrates ubiquitinated by PEX2 during amino acid starvation. PEX2 expression is upregulated during amino acid starvation and rapamycin treatment, indicating that mTORC1 pathway controls pexophagy by regulating PEX2 levels.\",\n      \"method\": \"PEX2 overexpression with ubiquitination assays, NBR1 knockdown rescue experiments, substrate identification (PEX5 and PMP70), mTOR pathway inhibitor treatment, in vivo animal model validation\",\n      \"journal\": \"The Journal of cell biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — multiple orthogonal methods (ubiquitination assay, substrate identification, pathway manipulation, in vivo validation), published in high-impact journal\",\n      \"pmids\": [\"27597759\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1997,\n      \"finding\": \"Targeted deletion of PEX2 in mice abolishes functional peroxisome assembly (leaving only empty membrane ghosts), causes accumulation of very long chain fatty acids, deficient plasmalogens, disordered neuronal migration in cerebral cortex, and neonatal lethality, establishing PEX2 as essential for peroxisomal biogenesis and function in vivo.\",\n      \"method\": \"Gene targeting/knockout in mice, biochemical analysis (VLCFA, plasmalogens), immunohistochemistry, neuroanatomical analysis\",\n      \"journal\": \"The Journal of cell biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — clean knockout with defined biochemical and cellular phenotypes, replicated in multiple subsequent studies\",\n      \"pmids\": [\"9382874\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2000,\n      \"finding\": \"A missense mutation changing cysteine-258 to tyrosine in the RING finger motif of PEX2 selectively abolishes PTS1-dependent peroxisomal protein import while leaving PTS2-dependent import (e.g., 3-ketoacyl-CoA thiolase) intact, demonstrating that the RING finger domain is specifically required for the PTS1 import pathway.\",\n      \"method\": \"Site-directed mutagenesis of RING finger domain, immunocytochemical localization of PTS1 and PTS2 cargo proteins in CHO mutant cells and stable transformants with wild-type or mutant PEX2 cDNA\",\n      \"journal\": \"Biochemical and biophysical research communications\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — active-site mutagenesis with functional readout in cell-based assay, rescue experiments, single lab\",\n      \"pmids\": [\"10772890\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2003,\n      \"finding\": \"The minimum peroxisomal membrane targeting signal of human PEX2 consists of an internal 30 amino acid region (AA130–159) plus the first transmembrane domain; the targeting motif 'KX6(I/L)X(L/F/I)LK(L/F/I)' within this region is essential, and mutations in it mislocalize PEX2 to the cytosol. The second transmembrane domain increases targeting efficiency but does not contain specific targeting information.\",\n      \"method\": \"GFP-fusion deletion constructs expressed in COS-7 cells with intracellular localization determination; motif mutagenesis; chimeric construct with heterologous transmembrane domain\",\n      \"journal\": \"European journal of cell biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — systematic deletion and mutagenesis analysis in cell-based assay, single lab, multiple constructs tested\",\n      \"pmids\": [\"12751901\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1998,\n      \"finding\": \"Overexpression of PMP70 (a 70 kDa peroxisomal membrane protein) suppresses the peroxisome biogenesis defect caused by PEX2 mutations in CHO cells, restoring catalase latency, catalase localization, and VLCFA beta-oxidation, suggesting a functional interaction between PEX2 and PMP70 in the peroxisome membrane. A disease-causing mutant allele of PMP70 did not rescue, confirming specificity.\",\n      \"method\": \"Expression of PMP70 in PEX2-deficient CHO cell clones, subcellular catalase latency assay, immunohistochemical localization of catalase, VLCFA beta-oxidation assay\",\n      \"journal\": \"European journal of cell biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — functional rescue assay with multiple readouts, mutant PMP70 control, single lab\",\n      \"pmids\": [\"9765053\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2000,\n      \"finding\": \"PEX2 encodes a 35-kDa peroxisomal membrane protein with two membrane-spanning domains and a C-terminal RING finger motif exposed to the cytosol. Mutations truncating the protein and removing both transmembrane domains and the RING domain cause severe disease, while a mutation disrupting only the C-terminal RING finger domain (del642G) causes milder phenotype with residual peroxisome assembly, demonstrating that the transmembrane domains are critical for peroxisome assembly and the C-terminal RING finger domain modulates import efficiency.\",\n      \"method\": \"Patient mutation characterization, expression of mutated PEX2 in PEX2-deficient CHO cells, immunocytochemistry for catalase-containing peroxisomes\",\n      \"journal\": \"Biochemical and biophysical research communications\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — domain function assigned via patient mutations and cell complementation assay, single lab\",\n      \"pmids\": [\"10652207\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2002,\n      \"finding\": \"PEX2 functions in the peroxisomal RING-finger complex downstream of both PEX5 (PTS1 receptor) and PEX7 (PTS2 receptor), making it required for import of both PTS1 and PTS2 proteins. Genetic epistasis in Podospora anserina shows that pex2 deletion causes both metabolic (oleic acid growth) and developmental (meiotic commitment) defects, and that PEX2 has functions beyond those of the PTS1/PTS2 receptors.\",\n      \"method\": \"Genetic epistasis analysis in Podospora anserina (single and double knockouts of pex2, pex5, pex7), immunofluorescence and GFP staining for peroxisome biogenesis, growth assays\",\n      \"journal\": \"Molecular microbiology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genetic epistasis with multiple mutant combinations and orthogonal readouts, single organism/lab\",\n      \"pmids\": [\"16987176\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2002,\n      \"finding\": \"PEX2 protein functions differentially in two steps of thiolase (PTS2 cargo) maturation: its RING finger domain (Cys258) is required for the final maturation/processing step of thiolase precursor, while a distinct domain supports initial peroxisomal docking/association of the precursor. CHO cells with Pex2pC258Y mutation accumulate thiolase precursor in peroxisomes rather than excluding it to cytosol, in contrast to complete truncation mutants.\",\n      \"method\": \"SDS-PAGE analysis of thiolase precursor form, salt wash, sodium carbonate extraction, proteinase K protection assay, differential digitonin permeabilization with immunofluorescence in five PEX2 CHO mutant cell lines\",\n      \"journal\": \"Biochimica et biophysica acta\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — multiple biochemical methods (membrane association, protease protection, size analysis) across multiple defined mutant cell lines, single lab\",\n      \"pmids\": [\"12031794\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2002,\n      \"finding\": \"A novel PEX2 point mutation (Arg50 nonsense) in CHO cells produces a unique phenotype: defective catalase import but temperature-sensitive PTS1 and PTS2 import (normal at 37°C, abrogated at 39°C), demonstrating that catalase import and general PTS1/PTS2 import are mechanistically separable functions of PEX2.\",\n      \"method\": \"Mutagenesis screen in CHO cells, temperature-shift experiments, immunolocalization of catalase and PTS1/PTS2 cargo proteins, sequencing of PEX2 mutation\",\n      \"journal\": \"Biochemical and biophysical research communications\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — temperature-sensitive allele with clear separation of import activities, single lab\",\n      \"pmids\": [\"12054689\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1996,\n      \"finding\": \"The Pichia pastoris PER6 gene product (Per6p), a homolog of human PAF-1/PEX2, is a peroxisomal integral membrane protein with a C3HC4 RING motif; loss of PER6 causes absence of morphologically recognizable peroxisomes and cytosolic mislocalization of peroxisomal matrix proteins, establishing the conserved role of this peroxin family in peroxisome biogenesis. Per6p is correctly targeted to mammalian peroxisomes, demonstrating evolutionary conservation of targeting.\",\n      \"method\": \"Gene cloning and functional complementation, immunolocalization, fractionation, cross-species targeting experiment (Per6p expressed in mammalian cells)\",\n      \"journal\": \"Molecular and cellular biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — loss-of-function phenotype plus heterologous targeting experiment, ortholog data consistent with mammalian PEX2 function\",\n      \"pmids\": [\"8628321\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"In yeast, the Pex2/Pex10/Pex12 E3-ubiquitin ligase complex assembles with the Pex5/Pex8 complex to initiate receptor recycling after cargo release into peroxisomes, as supported by structural and functional evidence showing that Pex8 interaction with Pex5 N-terminal domain is required for peroxisomal protein translocation and enables downstream assembly with the RING E3 complex.\",\n      \"method\": \"Cryo-EM/structural analysis of Pex8-Pex5 complex, functional translocation assays, mutagenesis of interaction interface\",\n      \"journal\": \"bioRxiv\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — structural data plus mutagenesis in yeast ortholog system, preprint not yet peer-reviewed, places PEX2 complex in receptor recycling pathway\",\n      \"pmids\": [\"bio_10.1101_2025.08.30.673231\"],\n      \"is_preprint\": true\n    }\n  ],\n  \"current_model\": \"PEX2 is a peroxisomal integral membrane protein containing two transmembrane domains and a cytoplasmic C3HC4 RING finger domain that functions as an E3 ubiquitin ligase: it mediates Ubc4-dependent polyubiquitination of the import receptor PEX5 to trigger its proteasomal degradation during normal import receptor recycling, and during nutrient starvation it ubiquitinates PEX5 and PMP70 to signal pexophagy via an NBR1-dependent autophagic pathway; the RING domain is also required for PTS1-dependent matrix protein import, while the transmembrane domains are essential for peroxisome membrane assembly, and together the Pex2/Pex10/Pex12 RING complex acts downstream of cargo/receptor recognition to coordinate cargo translocation and receptor recycling.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"PEX2 is a peroxisomal integral membrane protein essential for peroxisome biogenesis and matrix protein import, acting through a cytosol-exposed C3HC4 RING finger that confers E3 ubiquitin ligase activity [#0, #2]. Together with the RING peroxins PEX10 and PEX12, PEX2 mediates Ubc4-dependent polyubiquitination of the PTS1 import receptor PEX5, targeting it for proteasomal degradation as part of receptor recycling downstream of cargo recognition [#0]. Structurally, the protein spans the membrane twice via two transmembrane domains that carry its membrane-targeting information and are critical for peroxisome assembly, while the RING domain modulates import efficiency [#4, #6]; a point mutation in the RING motif (Cys258) selectively abolishes PTS1-dependent import and blocks the final maturation step of PTS2 cargo such as thiolase, showing that distinct PEX2 functions govern docking, translocation, and receptor handling [#3, #8]. PEX2 also serves as the E3 ligase for pexophagy: under amino acid starvation it ubiquitinates PEX5 and PMP70 to drive NBR1-dependent autophagic degradation of peroxisomes, with its expression controlled by mTORC1 signaling [#1]. Loss of PEX2 in mice abolishes functional peroxisome assembly, leaving only membrane ghosts, and causes very long chain fatty acid accumulation, plasmalogen deficiency, disordered neuronal migration, and neonatal lethality, and PEX2-truncating mutations cause severe peroxisome biogenesis disease in humans [#2, #6].\"\n,\n  \"teleology\": [\n    {\n      \"year\": 1996,\n      \"claim\": \"Established that the PEX2 family is a conserved peroxisomal integral membrane protein with a RING motif required for peroxisome biogenesis, answering whether this peroxin is needed for organelle formation.\",\n      \"evidence\": \"Gene cloning, loss-of-function, fractionation, and cross-species targeting of the Pichia pastoris PER6/PEX2 homolog\",\n      \"pmids\": [\"8628321\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Did not define the biochemical activity of the RING motif\", \"Ortholog-based; mammalian mechanism not directly tested\"]\n    },\n    {\n      \"year\": 1997,\n      \"claim\": \"Demonstrated in vivo that PEX2 is essential for functional peroxisome assembly and for peroxisomal lipid metabolism and brain development, establishing physiological consequences of its loss.\",\n      \"evidence\": \"PEX2 knockout mice with VLCFA/plasmalogen biochemistry and neuroanatomical analysis\",\n      \"pmids\": [\"9382874\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Did not resolve the molecular step PEX2 performs in import\", \"Mechanism linking assembly defect to neuronal migration unaddressed\"]\n    },\n    {\n      \"year\": 2000,\n      \"claim\": \"Separated the functional contributions of the transmembrane region and the RING domain, showing transmembrane domains drive assembly while the RING finger tunes import efficiency.\",\n      \"evidence\": \"Patient mutation characterization and complementation in PEX2-deficient CHO cells\",\n      \"pmids\": [\"10652207\", \"10772890\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Molecular activity of the RING domain not yet defined\", \"How the RING domain affects import efficiency mechanistically unclear\"]\n    },\n    {\n      \"year\": 2002,\n      \"claim\": \"Resolved that PEX2 acts downstream of both PTS1 and PTS2 receptors and contributes to multiple separable import steps, including thiolase maturation and a temperature-sensitive, catalase-specific import function.\",\n      \"evidence\": \"Genetic epistasis in Podospora anserina and biochemical/protease-protection analysis of multiple CHO PEX2 mutant alleles\",\n      \"pmids\": [\"16987176\", \"12031794\", \"12054689\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Did not identify the enzymatic mechanism distinguishing these steps\", \"Single-organism/lab evidence for each separable function\"]\n    },\n    {\n      \"year\": 2003,\n      \"claim\": \"Defined the peroxisomal membrane targeting signal of PEX2, answering how the protein reaches the peroxisome membrane.\",\n      \"evidence\": \"GFP-fusion deletion and motif mutagenesis in COS-7 cells\",\n      \"pmids\": [\"12751901\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Targeting machinery recognizing the motif not identified\", \"Single lab, cell-based assay only\"]\n    },\n    {\n      \"year\": 2009,\n      \"claim\": \"Identified PEX2 as a RING E3 ligase that polyubiquitinates PEX5 for proteasomal degradation via Ubc4, defining its molecular activity within the import/recycling cycle.\",\n      \"evidence\": \"In vitro ubiquitin ligase assays with defined E2 partners across the RING peroxins\",\n      \"pmids\": [\"19687296\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Did not define how E3 activity is regulated in vivo\", \"Relationship to membrane assembly function not integrated\"]\n    },\n    {\n      \"year\": 2016,\n      \"claim\": \"Showed PEX2 is the E3 ligase driving pexophagy, ubiquitinating PEX5 and PMP70 under starvation to trigger NBR1-dependent autophagy under mTORC1 control, extending its role from import recycling to organelle turnover.\",\n      \"evidence\": \"PEX2 overexpression ubiquitination assays, NBR1 knockdown rescue, substrate identification, mTOR inhibitor treatment, and in vivo validation\",\n      \"pmids\": [\"27597759\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"How a single ligase switches between recycling and pexophagy substrates unresolved\", \"Precise mTORC1-to-PEX2 transcriptional link not defined\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Placed the Pex2/Pex10/Pex12 RING complex into the structural sequence of receptor recycling, showing it assembles with the Pex5/Pex8 complex after cargo release.\",\n      \"evidence\": \"Cryo-EM/structural analysis and translocation/mutagenesis assays in yeast (preprint)\",\n      \"pmids\": [\"bio_10.1101_2025.08.30.673231\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Preprint, not peer-reviewed\", \"Yeast ortholog system; mammalian complex architecture not directly shown\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How PEX2 substrate choice and activity are switched between routine receptor recycling and starvation-induced pexophagy at the molecular level remains unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No mechanism defining recycling vs. pexophagy substrate selection\", \"Structural basis of mammalian RING complex assembly not established\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0016874\", \"supporting_discovery_ids\": [0, 1]},\n      {\"term_id\": \"GO:0140096\", \"supporting_discovery_ids\": [0, 1]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005778\", \"supporting_discovery_ids\": [4, 6, 10]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-9609507\", \"supporting_discovery_ids\": [0, 3, 7]},\n      {\"term_id\": \"R-HSA-9612973\", \"supporting_discovery_ids\": [1]},\n      {\"term_id\": \"R-HSA-1852241\", \"supporting_discovery_ids\": [2, 10]}\n    ],\n    \"complexes\": [\"Pex2/Pex10/Pex12 RING E3 ligase complex\"],\n    \"partners\": [\"PEX10\", \"PEX12\", \"PEX5\", \"PMP70\", \"NBR1\", \"PEX7\", \"PEX8\"],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":5,"faith_total":5,"faith_pct":100.0}}