{"gene":"COPG2","run_date":"2026-06-09T22:57:19","timeline":{"discoveries":[{"year":2011,"finding":"Tissue-specific alternative polyadenylation at the Mest locus produces longer RNA variants (MestXL) that extend >10 kb into the antisense gene Copg2; in CNS tissues where MestXL is expressed, transcriptional interference from MestXL causes preferential (maternal-allele-biased) expression of Copg2, whereas in non-CNS tissues Copg2 is biallelically expressed. A targeted truncation allele at Mest that abolishes MestXL formation also abolishes the allelic bias at Copg2, establishing MestXL-mediated transcriptional interference as the mechanistic basis for tissue-specific allelic regulation of Copg2.","method":"Targeted allele truncation at Mest locus, allele-specific expression analysis, alternative polyadenylation mapping in mouse embryos","journal":"Nucleic acids research","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — genetic epistasis via targeted allele with clear allele-specific phenotype, single lab, two orthogonal methods (truncation mutant + allele-specific expression)","pmids":["22053079"],"is_preprint":false},{"year":2003,"finding":"A differentially methylated region (DMR) with paternal-specific methylation exists at the promoter-associated CpG island of mouse Copg2; however, in the interspecific F1 hybrid (C57BL/6 × M. spretus), this paternal-specific methylation is not accompanied by allele-specific (monoallelic) expression of Copg2, demonstrating that promoter CpG island methylation alone is not sufficient to silence Copg2 expression. A novel antisense transcript (Copg2AS2) originating at the Copg2 promoter region is expressed monoallelically and correlates with the differential methylation.","method":"Bisulfite sequencing / methylation analysis of CpG island in interspecific F1 hybrid mice; allele-specific expression analysis; identification of antisense transcript","journal":"Mammalian genome","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — direct methylation mapping combined with allele-specific expression in hybrid mouse model, single lab, two orthogonal methods","pmids":["12879359"],"is_preprint":false},{"year":2000,"finding":"Mouse Copg2 is paternally imprinted (preferentially expressed from the maternal allele) in embryos, neonates, and adult brain, with partial imprinting in other tissues; an antisense transcript Copg2AS overlapping the 3'-UTRs of Copg2 and Peg1/Mest is maternally imprinted, indicating a reciprocal imprinting relationship between the sense and antisense transcripts at this locus.","method":"Allele-specific expression analysis in intraspecific F1 hybrid mice (C57BL/6 × M. m. molossinus); Northern blot; RT-PCR","journal":"FEBS letters","confidence":"Low","confidence_rationale":"Tier 3 / Weak — single lab, single allele-specific expression method; imprinting status later found to be species/strain-dependent","pmids":["10788617"],"is_preprint":false},{"year":2000,"finding":"Human COPG2 (gamma2-COP) on chromosome 7q32 escapes genomic imprinting and is biallelically expressed in all fetal tissues and adult blood lymphocytes examined; an antisense transcript CIT1 within intron 20 of COPG2 is paternally expressed (monoallelic) in fetal tissues, establishing allelic asymmetry only at the non-coding antisense transcript and not the COPG2 protein-coding gene itself.","method":"Allele-specific expression analysis using SNPs in human fetal tissue panels; RT-PCR","journal":"Genomics","confidence":"Low","confidence_rationale":"Tier 3 / Weak — single lab, SNP-based allele-specific RT-PCR, no functional mechanistic follow-up","pmids":["10995575"],"is_preprint":false}],"current_model":"COPG2 encodes a coatomer (COPI) complex subunit whose allelic expression is regulated in a tissue-specific manner through transcriptional interference by the overlapping antisense MestXL transcript: in the developing CNS, alternative polyadenylation at the Mest locus generates MestXL RNAs that extend into Copg2 and suppress the paternal allele, whereas in non-CNS tissues COPG2 is biallelically expressed; a paternal-specific DMR at the Copg2 promoter CpG island is necessary but not sufficient for monoallelic silencing, and imprinting status varies across species and strains."},"narrative":{"mechanistic_narrative":"COPG2 encodes a coatomer (COPI) complex subunit (gamma2-COP) whose locus is a model for tissue- and species-specific allelic regulation rather than for vesicle-trafficking mechanism per se in the available corpus [PMID:22053079]. In mouse, Copg2 is subject to allele-biased expression driven by its genomic neighbor Mest: tissue-specific alternative polyadenylation at Mest generates extended antisense MestXL transcripts that read >10 kb into Copg2, and this transcriptional interference produces maternal-allele-biased Copg2 expression in CNS tissues while non-CNS tissues remain biallelic; truncating Mest to abolish MestXL also abolishes the Copg2 allelic bias, establishing MestXL-mediated transcriptional interference as the causal mechanism [PMID:22053079]. A paternal-specific differentially methylated region at the Copg2 promoter CpG island is associated with the locus but is insufficient on its own to silence Copg2, since in an interspecific hybrid the methylation occurs without monoallelic expression [PMID:12879359]. The locus is further marked by reciprocally imprinted antisense transcripts (Copg2AS, Copg2AS2, and human CIT1), and human COPG2 itself escapes imprinting and is biallelically expressed while the antisense transcript alone shows allelic asymmetry [PMID:12879359, PMID:10995575]. The molecular and cellular function of the COPG2 protein in COPI coat assembly or trafficking has not been characterized in the available corpus.","teleology":[{"year":2000,"claim":"Established whether the Copg2 locus is imprinted, addressing how allelic dosage is set at this gene region.","evidence":"Allele-specific expression, Northern blot and RT-PCR in intraspecific F1 hybrid mice","pmids":["10788617"],"confidence":"Low","gaps":["Single allele-specific expression method, not independently confirmed at the time","Imprinting status later found to be species/strain-dependent","No mechanism for the maternal/paternal expression bias identified"]},{"year":2000,"claim":"Tested whether imprinting of the locus is conserved in human, clarifying that the protein-coding gene and its antisense transcript are regulated separately.","evidence":"SNP-based allele-specific RT-PCR across human fetal tissue panels","pmids":["10995575"],"confidence":"Low","gaps":["Human COPG2 escapes imprinting while only the antisense CIT1 shows allelic asymmetry, leaving the functional consequence unclear","No mechanistic follow-up on how CIT1 monoallelic expression is established","Single lab, RT-PCR only"]},{"year":2003,"claim":"Asked whether promoter CpG-island methylation explains allelic silencing, and showed methylation is necessary-associated but not sufficient.","evidence":"Bisulfite methylation mapping plus allele-specific expression in interspecific (C57BL/6 x M. spretus) hybrid mice","pmids":["12879359"],"confidence":"Medium","gaps":["Does not identify the additional factor required for silencing","Antisense Copg2AS2 correlation with methylation is not shown to be causal","Hybrid-specific result may not generalize across strains"]},{"year":2011,"claim":"Resolved the causal mechanism of tissue-specific allelic bias by showing antisense MestXL read-through transcription interferes with Copg2.","evidence":"Targeted Mest truncation allele abolishing MestXL, with allele-specific expression and polyadenylation mapping in mouse embryos","pmids":["22053079"],"confidence":"Medium","gaps":["Mechanism demonstrated genetically but molecular details of interference (e.g. polymerase collision vs. chromatin) not resolved","Single lab","Does not address COPG2 protein function or trafficking role"]},{"year":null,"claim":"The molecular and cellular function of the COPG2 protein within the COPI coatomer complex remains uncharacterized in this corpus.","evidence":"No direct biochemical or cell-biological study of COPG2 protein in the timeline","pmids":[],"confidence":"Low","gaps":["No data on COPI coat assembly role","No interaction partners experimentally defined","No localization or trafficking phenotype established"]}],"mechanism_profile":{"molecular_activity":[],"localization":[],"pathway":[],"complexes":["COPI coatomer"],"partners":[],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"Q9UBF2","full_name":"Coatomer subunit gamma-2","aliases":["Gamma-2-coat protein","Gamma-2-COP"],"length_aa":871,"mass_kda":97.6,"function":"The coatomer is a cytosolic protein complex that binds to dilysine motifs and reversibly associates with Golgi non-clathrin-coated vesicles, which further mediate biosynthetic protein transport from the ER, via the Golgi up to the trans Golgi network. Coatomer complex is required for budding from Golgi membranes, and is essential for the retrograde Golgi-to-ER transport of dilysine-tagged proteins. In mammals, the coatomer can only be recruited by membranes associated to ADP-ribosylation factors (ARFs), which are small GTP-binding proteins; the complex also influences the Golgi structural integrity, as well as the processing, activity, and endocytic recycling of LDL receptors (By similarity)","subcellular_location":"Cytoplasm, cytosol; Golgi apparatus membrane; Cytoplasmic vesicle, COPI-coated vesicle membrane","url":"https://www.uniprot.org/uniprotkb/Q9UBF2/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/COPG2","classification":"Not Classified","n_dependent_lines":4,"n_total_lines":74,"dependency_fraction":0.05405405405405406},"opencell":{"profiled":true,"resolved_as":"","ensg_id":"ENSG00000158623","cell_line_id":"CID000916","localizations":[{"compartment":"golgi","grade":3},{"compartment":"vesicles","grade":2},{"compartment":"cytoplasmic","grade":1}],"interactors":[{"gene":"COPA","stoichiometry":10.0},{"gene":"COPB2","stoichiometry":10.0},{"gene":"COPE","stoichiometry":10.0},{"gene":"SPTLC1","stoichiometry":10.0},{"gene":"ATL2","stoichiometry":4.0},{"gene":"ARFGAP1","stoichiometry":0.2},{"gene":"CANX","stoichiometry":0.2},{"gene":"BCAP31","stoichiometry":0.2},{"gene":"ATL3","stoichiometry":0.2},{"gene":"ARL6IP5","stoichiometry":0.2}],"url":"https://opencell.sf.czbiohub.org/target/CID000916","total_profiled":1310},"omim":[{"mim_id":"618905","title":"SILVER-RUSSELL SYNDROME 2; SRS2","url":"https://www.omim.org/entry/618905"},{"mim_id":"616012","title":"JAGUNAL HOMOLOG 1; JAGN1","url":"https://www.omim.org/entry/616012"},{"mim_id":"615526","title":"COATOMER PROTEIN COMPLEX, SUBUNIT ZETA-2; COPZ2","url":"https://www.omim.org/entry/615526"},{"mim_id":"615525","title":"COATOMER PROTEIN COMPLEX, SUBUNIT GAMMA-1; COPG1","url":"https://www.omim.org/entry/615525"},{"mim_id":"615472","title":"COATOMER PROTEIN COMPLEX, SUBUNIT ZETA-1; COPZ1","url":"https://www.omim.org/entry/615472"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"","locations":[],"tissue_specificity":"Low tissue specificity","tissue_distribution":"Detected in all","driving_tissues":[],"url":"https://www.proteinatlas.org/search/COPG2"},"hgnc":{"alias_symbol":["2-COP"],"prev_symbol":[]},"alphafold":{"accession":"Q9UBF2","domains":[{"cath_id":"2.60.40.1480","chopping":"607-755","consensus_level":"high","plddt":91.3892,"start":607,"end":755},{"cath_id":"3.30.310.10","chopping":"758-869","consensus_level":"high","plddt":90.8454,"start":758,"end":869},{"cath_id":"1.25.40","chopping":"446-548","consensus_level":"medium","plddt":93.0436,"start":446,"end":548}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q9UBF2","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q9UBF2-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q9UBF2-F1-predicted_aligned_error_v6.png","plddt_mean":87.81},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=COPG2","jax_strain_url":"https://www.jax.org/strain/search?query=COPG2"},"sequence":{"accession":"Q9UBF2","fasta_url":"https://rest.uniprot.org/uniprotkb/Q9UBF2.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q9UBF2/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q9UBF2"}},"corpus_meta":[{"pmid":"10788617","id":"PMC_10788617","title":"Mit1/Lb9 and Copg2, new members of mouse imprinted genes closely linked to Peg1/Mest(1).","date":"2000","source":"FEBS letters","url":"https://pubmed.ncbi.nlm.nih.gov/10788617","citation_count":48,"is_preprint":false},{"pmid":"10995575","id":"PMC_10995575","title":"The novel gene, gamma2-COP (COPG2), in the 7q32 imprinted domain escapes genomic imprinting.","date":"2000","source":"Genomics","url":"https://pubmed.ncbi.nlm.nih.gov/10995575","citation_count":29,"is_preprint":false},{"pmid":"22053079","id":"PMC_22053079","title":"Tissue-specific alternative polyadenylation at the imprinted gene Mest regulates allelic usage at Copg2.","date":"2011","source":"Nucleic acids research","url":"https://pubmed.ncbi.nlm.nih.gov/22053079","citation_count":20,"is_preprint":false},{"pmid":"33484489","id":"PMC_33484489","title":"Interface Engineering of Needle-Like P-Doped MoS2 /CoP Arrays as Highly Active and Durable Bifunctional Electrocatalyst for Overall Water Splitting.","date":"2021","source":"ChemSusChem","url":"https://pubmed.ncbi.nlm.nih.gov/33484489","citation_count":20,"is_preprint":false},{"pmid":"22456293","id":"PMC_22456293","title":"Methylation and expression analyses of the 7q autism susceptibility locus genes MEST , COPG2, and TSGA14 in human and anthropoid primate cortices.","date":"2012","source":"Cytogenetic and genome research","url":"https://pubmed.ncbi.nlm.nih.gov/22456293","citation_count":17,"is_preprint":false},{"pmid":"16151700","id":"PMC_16151700","title":"The COPG2, DCN, and SDHD genes are biallelically expressed in cattle.","date":"2005","source":"Mammalian genome : official journal of the International Mammalian Genome Society","url":"https://pubmed.ncbi.nlm.nih.gov/16151700","citation_count":15,"is_preprint":false},{"pmid":"11032317","id":"PMC_11032317","title":"Molecular cloning and characterization of the Fugu rubripes MEST/COPG2 imprinting cluster and chromosomal localization in Fugu and Tetraodon nigroviridis.","date":"2000","source":"Chromosome research : an international journal on the molecular, supramolecular and evolutionary aspects of chromosome biology","url":"https://pubmed.ncbi.nlm.nih.gov/11032317","citation_count":11,"is_preprint":false},{"pmid":"12879359","id":"PMC_12879359","title":"Allele-specific methylation at the promoter-associated CpG island of mouse Copg2.","date":"2003","source":"Mammalian genome : official journal of the International Mammalian Genome Society","url":"https://pubmed.ncbi.nlm.nih.gov/12879359","citation_count":4,"is_preprint":false},{"pmid":"41088870","id":"PMC_41088870","title":"Atomic Pt-Promoted Hierarchical CoP@CNTs-Bridged CeO2-CoP Heterostructure-Based Hollow Microcubes for Water Electrolysis.","date":"2025","source":"Small (Weinheim an der Bergstrasse, Germany)","url":"https://pubmed.ncbi.nlm.nih.gov/41088870","citation_count":3,"is_preprint":false},{"pmid":"37266760","id":"PMC_37266760","title":"The presence of β'1-COP and β'2-COP is required for female and male gametophyte development.","date":"2023","source":"Plant reproduction","url":"https://pubmed.ncbi.nlm.nih.gov/37266760","citation_count":2,"is_preprint":false},{"pmid":null,"id":"bio_10.1101_2025.03.09.642261","title":"An extensive and unbiased genome-wide scan for parent-of-origin expressed genes in the pig clarifies the conservation landscape of genomic imprinting","date":"2025-03-13","source":"bioRxiv","url":"https://doi.org/10.1101/2025.03.09.642261","citation_count":0,"is_preprint":true}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":7249,"output_tokens":1295,"usd":0.020586,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":7898,"output_tokens":1685,"usd":0.040807,"stage2_stop_reason":"end_turn"},"total_usd":0.061393,"stage1_batch_id":"msgbatch_01ACAxJQabDsht39JXeWG22d","stage2_batch_id":"msgbatch_01QEU22A9U5sbPTgsMzTmvSf","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2011,\n      \"finding\": \"Tissue-specific alternative polyadenylation at the Mest locus produces longer RNA variants (MestXL) that extend >10 kb into the antisense gene Copg2; in CNS tissues where MestXL is expressed, transcriptional interference from MestXL causes preferential (maternal-allele-biased) expression of Copg2, whereas in non-CNS tissues Copg2 is biallelically expressed. A targeted truncation allele at Mest that abolishes MestXL formation also abolishes the allelic bias at Copg2, establishing MestXL-mediated transcriptional interference as the mechanistic basis for tissue-specific allelic regulation of Copg2.\",\n      \"method\": \"Targeted allele truncation at Mest locus, allele-specific expression analysis, alternative polyadenylation mapping in mouse embryos\",\n      \"journal\": \"Nucleic acids research\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genetic epistasis via targeted allele with clear allele-specific phenotype, single lab, two orthogonal methods (truncation mutant + allele-specific expression)\",\n      \"pmids\": [\"22053079\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2003,\n      \"finding\": \"A differentially methylated region (DMR) with paternal-specific methylation exists at the promoter-associated CpG island of mouse Copg2; however, in the interspecific F1 hybrid (C57BL/6 × M. spretus), this paternal-specific methylation is not accompanied by allele-specific (monoallelic) expression of Copg2, demonstrating that promoter CpG island methylation alone is not sufficient to silence Copg2 expression. A novel antisense transcript (Copg2AS2) originating at the Copg2 promoter region is expressed monoallelically and correlates with the differential methylation.\",\n      \"method\": \"Bisulfite sequencing / methylation analysis of CpG island in interspecific F1 hybrid mice; allele-specific expression analysis; identification of antisense transcript\",\n      \"journal\": \"Mammalian genome\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — direct methylation mapping combined with allele-specific expression in hybrid mouse model, single lab, two orthogonal methods\",\n      \"pmids\": [\"12879359\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2000,\n      \"finding\": \"Mouse Copg2 is paternally imprinted (preferentially expressed from the maternal allele) in embryos, neonates, and adult brain, with partial imprinting in other tissues; an antisense transcript Copg2AS overlapping the 3'-UTRs of Copg2 and Peg1/Mest is maternally imprinted, indicating a reciprocal imprinting relationship between the sense and antisense transcripts at this locus.\",\n      \"method\": \"Allele-specific expression analysis in intraspecific F1 hybrid mice (C57BL/6 × M. m. molossinus); Northern blot; RT-PCR\",\n      \"journal\": \"FEBS letters\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — single lab, single allele-specific expression method; imprinting status later found to be species/strain-dependent\",\n      \"pmids\": [\"10788617\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2000,\n      \"finding\": \"Human COPG2 (gamma2-COP) on chromosome 7q32 escapes genomic imprinting and is biallelically expressed in all fetal tissues and adult blood lymphocytes examined; an antisense transcript CIT1 within intron 20 of COPG2 is paternally expressed (monoallelic) in fetal tissues, establishing allelic asymmetry only at the non-coding antisense transcript and not the COPG2 protein-coding gene itself.\",\n      \"method\": \"Allele-specific expression analysis using SNPs in human fetal tissue panels; RT-PCR\",\n      \"journal\": \"Genomics\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — single lab, SNP-based allele-specific RT-PCR, no functional mechanistic follow-up\",\n      \"pmids\": [\"10995575\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"COPG2 encodes a coatomer (COPI) complex subunit whose allelic expression is regulated in a tissue-specific manner through transcriptional interference by the overlapping antisense MestXL transcript: in the developing CNS, alternative polyadenylation at the Mest locus generates MestXL RNAs that extend into Copg2 and suppress the paternal allele, whereas in non-CNS tissues COPG2 is biallelically expressed; a paternal-specific DMR at the Copg2 promoter CpG island is necessary but not sufficient for monoallelic silencing, and imprinting status varies across species and strains.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"COPG2 encodes a coatomer (COPI) complex subunit (gamma2-COP) whose locus is a model for tissue- and species-specific allelic regulation rather than for vesicle-trafficking mechanism per se in the available corpus [#0]. In mouse, Copg2 is subject to allele-biased expression driven by its genomic neighbor Mest: tissue-specific alternative polyadenylation at Mest generates extended antisense MestXL transcripts that read >10 kb into Copg2, and this transcriptional interference produces maternal-allele-biased Copg2 expression in CNS tissues while non-CNS tissues remain biallelic; truncating Mest to abolish MestXL also abolishes the Copg2 allelic bias, establishing MestXL-mediated transcriptional interference as the causal mechanism [#0]. A paternal-specific differentially methylated region at the Copg2 promoter CpG island is associated with the locus but is insufficient on its own to silence Copg2, since in an interspecific hybrid the methylation occurs without monoallelic expression [#1]. The locus is further marked by reciprocally imprinted antisense transcripts (Copg2AS, Copg2AS2, and human CIT1), and human COPG2 itself escapes imprinting and is biallelically expressed while the antisense transcript alone shows allelic asymmetry [#1, #3]. The molecular and cellular function of the COPG2 protein in COPI coat assembly or trafficking has not been characterized in the available corpus.\"\n,\n  \"teleology\": [\n    {\n      \"year\": 2000,\n      \"claim\": \"Established whether the Copg2 locus is imprinted, addressing how allelic dosage is set at this gene region.\",\n      \"evidence\": \"Allele-specific expression, Northern blot and RT-PCR in intraspecific F1 hybrid mice\",\n      \"pmids\": [\"10788617\"],\n      \"confidence\": \"Low\",\n      \"gaps\": [\"Single allele-specific expression method, not independently confirmed at the time\", \"Imprinting status later found to be species/strain-dependent\", \"No mechanism for the maternal/paternal expression bias identified\"]\n    },\n    {\n      \"year\": 2000,\n      \"claim\": \"Tested whether imprinting of the locus is conserved in human, clarifying that the protein-coding gene and its antisense transcript are regulated separately.\",\n      \"evidence\": \"SNP-based allele-specific RT-PCR across human fetal tissue panels\",\n      \"pmids\": [\"10995575\"],\n      \"confidence\": \"Low\",\n      \"gaps\": [\"Human COPG2 escapes imprinting while only the antisense CIT1 shows allelic asymmetry, leaving the functional consequence unclear\", \"No mechanistic follow-up on how CIT1 monoallelic expression is established\", \"Single lab, RT-PCR only\"]\n    },\n    {\n      \"year\": 2003,\n      \"claim\": \"Asked whether promoter CpG-island methylation explains allelic silencing, and showed methylation is necessary-associated but not sufficient.\",\n      \"evidence\": \"Bisulfite methylation mapping plus allele-specific expression in interspecific (C57BL/6 x M. spretus) hybrid mice\",\n      \"pmids\": [\"12879359\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Does not identify the additional factor required for silencing\", \"Antisense Copg2AS2 correlation with methylation is not shown to be causal\", \"Hybrid-specific result may not generalize across strains\"]\n    },\n    {\n      \"year\": 2011,\n      \"claim\": \"Resolved the causal mechanism of tissue-specific allelic bias by showing antisense MestXL read-through transcription interferes with Copg2.\",\n      \"evidence\": \"Targeted Mest truncation allele abolishing MestXL, with allele-specific expression and polyadenylation mapping in mouse embryos\",\n      \"pmids\": [\"22053079\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Mechanism demonstrated genetically but molecular details of interference (e.g. polymerase collision vs. chromatin) not resolved\", \"Single lab\", \"Does not address COPG2 protein function or trafficking role\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"The molecular and cellular function of the COPG2 protein within the COPI coatomer complex remains uncharacterized in this corpus.\",\n      \"evidence\": \"No direct biochemical or cell-biological study of COPG2 protein in the timeline\",\n      \"pmids\": [],\n      \"confidence\": \"Low\",\n      \"gaps\": [\"No data on COPI coat assembly role\", \"No interaction partners experimentally defined\", \"No localization or trafficking phenotype established\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [],\n    \"localization\": [],\n    \"pathway\": [],\n    \"complexes\": [\"COPI coatomer\"],\n    \"partners\": [],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"loss","faith_supported":4,"faith_total":4,"faith_pct":100.0}}