{"gene":"MACO1","run_date":"2026-06-10T02:59:50","timeline":{"discoveries":[{"year":2011,"finding":"MACO-1 (macoilin) is expressed broadly and specifically in the nervous system of C. elegans and localizes to the rough endoplasmic reticulum; it is excluded from dendrites and axons. Loss of maco-1 causes resistance to the cholinesterase inhibitor aldicarb and sensitivity to levamisole, indicating pre-synaptic defects. In maco-1 mutants, the O2-sensing neuron PQR fails to generate Ca2+ responses to rising O2, a defect that mirrors mutations in egl-19 (L-type voltage-gated Ca2+ channel α1 subunit), leading to the conclusion that macoilin acts in the ER to regulate assembly or trafficking of ion channels or ion channel regulators.","method":"Fluorescent protein localization, in vivo Ca2+ imaging, pharmacological assays (aldicarb/levamisole), genetic epistasis with egl-19/nca-1/nca-2 mutants","journal":"PLoS genetics","confidence":"High","confidence_rationale":"Tier 2 / Strong — multiple orthogonal methods (live imaging, pharmacology, genetic epistasis) in one study, independently replicated in a second concurrent publication (PMID:21589894)","pmids":["21437263"],"is_preprint":false},{"year":2011,"finding":"Human macoilin (MACO1/TMEM57) and C. elegans MACO-1 both localize primarily to the rough endoplasmic reticulum. Expression of human macoilin in the C. elegans nervous system weakly rescues the thermotactic phenotype of maco-1 mutants, indicating functional conservation across species. maco-1 mutants show defective Ca2+ responses in AFD thermosensory neurons and AIY interneurons to thermal stimuli.","method":"Subcellular fractionation/localization, cross-species rescue by human MACO1 expression, in vivo Ca2+ imaging of AFD and AIY neurons","journal":"PLoS genetics","confidence":"High","confidence_rationale":"Tier 2 / Strong — localization with functional consequence, cross-species rescue, Ca2+ imaging; replicates ER localization finding of PMID:21437263","pmids":["21589894"],"is_preprint":false},{"year":2017,"finding":"MACO-1 functions downstream of the TIR-1/JNK-1 pathway to regulate forgetting of olfactory adaptation in C. elegans. Genetic screening identified maco-1 as a suppressor of the tir-1 gain-of-function excessive-forgetting phenotype. MACO-1 and the SCD-2/HEN-1 receptor tyrosine kinase–ligand pair act in parallel genetic pathways; only MACO-1 regulates forgetting of adaptation to isoamyl alcohol (sensed by different neuron types). Ca2+ imaging showed that odor-evoked Ca2+ response attenuation is sustained longer in maco-1 mutants, indicating that MACO-1 promotes recovery of sensory responses after conditioning.","method":"Forward genetic suppressor screen, double-mutant epistasis analysis, in vivo Ca2+ imaging, temporal neuronal silencing with histamine-gated chloride channels","journal":"The Journal of neuroscience","confidence":"High","confidence_rationale":"Tier 2 / Moderate — genetic epistasis plus Ca2+ imaging, multiple orthogonal methods in single lab","pmids":["28924007"],"is_preprint":false},{"year":2016,"finding":"maco-1 is required for pheromone-induced dauer formation in C. elegans, placing MACO-1 in the pathway for detection, transmission, or integration of ascaroside pheromone signals.","method":"Forward genetic screen (unbiased EMS mutagenesis), dauer formation assays","journal":"G3 (Bethesda, Md.)","confidence":"Medium","confidence_rationale":"Tier 3 / Weak — single genetic screen with phenotypic readout, no direct molecular mechanism established","pmids":["26976437"],"is_preprint":false},{"year":2020,"finding":"The C. elegans gene maco-1 is the target of P. aeruginosa PA14 non-coding small RNA P11; knockdown/loss of maco-1 is required for bacterially-induced pathogen avoidance behavior and its transgenerational inheritance. The RNAi and piRNA pathways, the germline, and the ASI neuron are all required for this behavior, placing maco-1 downstream of a trans-kingdom sRNA silencing pathway.","method":"Bacterial sRNA purification and feeding, RNAi knockdown, loss-of-function genetics, behavioral assays (avoidance), epistasis with RNAi/piRNA pathway mutants","journal":"Nature","confidence":"High","confidence_rationale":"Tier 2 / Strong — necessity and sufficiency of P11 sRNA shown, maco-1 loss-of-function required for avoidance, pathway placement via epistasis, replicated in subsequent independent studies","pmids":["32908307"],"is_preprint":false},{"year":2024,"finding":"A P. vranovensis small RNA, Pv1, with 16-nt complementarity to an exon of C. elegans maco-1 is both necessary and sufficient to induce learned avoidance of P. vranovensis and its transgenerational inheritance, confirming that maco-1 downregulation by bacterial sRNAs is a conserved mechanism used by distinct Pseudomonas species.","method":"Bacterial sRNA sequencing, sRNA deletion and rescue (necessity/sufficiency), behavioral avoidance assays, transgenerational inheritance assays","journal":"PLoS genetics","confidence":"High","confidence_rationale":"Tier 2 / Strong — necessity and sufficiency demonstrated with clean genetic experiments, independent replication of the maco-1 sRNA-targeting mechanism","pmids":["38547071"],"is_preprint":false},{"year":2025,"finding":"VAB-1 loss reduces maco-1 expression, and knockdown of both vab-1 and maco-1 induces P. fluorescens avoidance, placing both genes in the same bacterial sRNA-targeted pathogenic avoidance pathway. This genetic interaction places MACO-1 downstream of or parallel to VAB-1 in the avoidance circuit.","method":"RNAi knockdown, genetic epistasis, expression analysis, behavioral avoidance assays","journal":"Science advances","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — epistasis and expression analysis in single lab, but mechanistic detail of MACO-1's placement relative to VAB-1 is based on expression level changes rather than direct biochemical interaction","pmids":["40267186"],"is_preprint":false},{"year":2002,"finding":"The mouse orthologue of FLJ10747 (MACO1) shows slightly higher expression in testis relative to other tissues, and subcellular localization experiments indicate a strong nuclear localization, in contrast to SMP1 which is cytoplasmic.","method":"Tissue distribution analysis, subcellular localization by genomic/expression analysis of syntenic region","journal":"Gene","confidence":"Low","confidence_rationale":"Tier 3 / Weak — single study, method details minimal in abstract, only localization reported with no functional consequence described","pmids":["12459264"],"is_preprint":false}],"current_model":"MACO1 (macoilin/TMEM57) encodes a conserved multi-transmembrane ER-resident protein expressed specifically in neurons, where it acts within the endoplasmic reticulum to regulate ion channel assembly or trafficking (particularly involving the L-type Ca2+ channel EGL-19), thereby controlling neuronal excitability, sensory Ca2+ responses, and behaviors including O2 sensing, thermotaxis, olfactory adaptation forgetting, and pheromone-induced dauer formation; in C. elegans, maco-1 is also the molecular target of bacterial pathogen-derived small RNAs (PA14-P11, Pv1) that silence its expression via the RNAi/piRNA pathway to induce transgenerational learned avoidance of pathogens."},"narrative":{"mechanistic_narrative":"MACO1 (macoilin/TMEM57) encodes a conserved multi-transmembrane protein of the rough endoplasmic reticulum that is expressed broadly and specifically in the nervous system, where it controls neuronal excitability and sensory signaling [PMID:21437263, PMID:21589894]. In C. elegans, loss of maco-1 produces presynaptic neurotransmission defects (aldicarb resistance, levamisole sensitivity) and abolishes the rising-O2 Ca2+ response of the PQR sensory neuron in a manner mirroring mutation of the L-type voltage-gated Ca2+ channel α1 subunit egl-19, supporting a model in which macoilin acts within the ER to regulate the assembly or trafficking of ion channels or their regulators [PMID:21437263]. ER localization and a neuronal function are conserved: human MACO1 localizes to the rough ER and weakly rescues the thermotaxis defect of maco-1 mutants, which themselves show altered thermosensory Ca2+ responses in AFD and AIY neurons [PMID:21589894]. Through this control of sensory Ca2+ dynamics, MACO-1 acts downstream of the TIR-1/JNK-1 pathway to promote recovery of attenuated odor-evoked responses, thereby driving forgetting of olfactory adaptation, and is also required for pheromone-induced dauer formation [PMID:28924007, PMID:26976437]. Independently, maco-1 is the molecular endpoint of a trans-kingdom small-RNA silencing mechanism: small RNAs from Pseudomonas species (PA14-derived P11; P. vranovensis Pv1) bear complementarity to maco-1 and downregulate it via the RNAi/piRNA pathway to drive learned, transgenerationally inherited pathogen avoidance, a circuit in which maco-1 acts downstream of or parallel to the VAB-1 receptor [PMID:32908307, PMID:38547071, PMID:40267186].","teleology":[{"year":2011,"claim":"Established macoilin as a neuron-specific rough-ER protein whose loss disrupts presynaptic function and sensory Ca2+ responses, generating the model that it regulates ion channel assembly/trafficking from the ER.","evidence":"Fluorescent localization, in vivo Ca2+ imaging of PQR, aldicarb/levamisole pharmacology, and genetic epistasis with egl-19/nca-1/nca-2 in C. elegans","pmids":["21437263"],"confidence":"High","gaps":["No direct biochemical demonstration that macoilin binds or chaperones EGL-19 or other channels","Mechanism distinguishing assembly versus trafficking not resolved"]},{"year":2011,"claim":"Demonstrated cross-species conservation of ER localization and neuronal function, showing human MACO1 can substitute for the worm protein in thermotaxis.","evidence":"Subcellular localization, cross-species rescue by human MACO1 expression, and Ca2+ imaging of AFD/AIY neurons","pmids":["21589894"],"confidence":"High","gaps":["Rescue was only weak/partial","Human MACO1 molecular activity not directly assayed in a mammalian system"]},{"year":2016,"claim":"Placed MACO-1 in pheromone signaling by showing it is required for ascaroside-pheromone-induced dauer formation.","evidence":"Forward EMS genetic screen and dauer formation assays in C. elegans","pmids":["26976437"],"confidence":"Medium","gaps":["No molecular mechanism linking MACO-1 to pheromone detection/integration","Site of action within the dauer pathway undefined"]},{"year":2017,"claim":"Connected MACO-1 to a defined signaling pathway by showing it acts downstream of TIR-1/JNK-1 to promote recovery of sensory Ca2+ responses and forgetting of olfactory adaptation.","evidence":"Forward suppressor screen, double-mutant epistasis, in vivo Ca2+ imaging, and histamine-gated chloride channel neuronal silencing","pmids":["28924007"],"confidence":"High","gaps":["How ER-localized MACO-1 mechanistically restores Ca2+ response recovery is unknown","Relationship between this role and channel trafficking not established"]},{"year":2020,"claim":"Identified maco-1 as the silencing target of a bacterial non-coding small RNA, defining it as the genetic endpoint of a trans-kingdom RNAi/piRNA pathway driving heritable pathogen avoidance.","evidence":"PA14 sRNA purification and feeding, RNAi knockdown, loss-of-function genetics, and behavioral/transgenerational assays with RNAi/piRNA pathway epistasis","pmids":["32908307"],"confidence":"High","gaps":["How reduced MACO-1 in specific neurons translates to avoidance behavior not mechanistically resolved","Link between ER/channel function and avoidance circuit not established"]},{"year":2024,"claim":"Generalized the sRNA-targeting mechanism by showing a distinct Pseudomonas species uses an independent small RNA (Pv1) complementary to maco-1 to induce heritable avoidance.","evidence":"Bacterial sRNA sequencing, sRNA deletion/rescue for necessity and sufficiency, and transgenerational avoidance assays","pmids":["38547071"],"confidence":"High","gaps":["Whether other pathogens converge on maco-1 broadly unknown","Downstream consequences of maco-1 downregulation on neuronal physiology not measured"]},{"year":2025,"claim":"Positioned MACO-1 relative to the VAB-1 receptor within the avoidance circuit, showing VAB-1 loss reduces maco-1 expression and combined knockdown induces avoidance.","evidence":"RNAi knockdown, genetic epistasis, expression analysis, and behavioral avoidance assays","pmids":["40267186"],"confidence":"Medium","gaps":["Placement inferred from expression-level changes, not direct biochemical interaction","Whether VAB-1 regulates maco-1 directly or indirectly unknown"]},{"year":null,"claim":"The biochemical activity of macoilin at the ER — its direct binding partners, the channels it assembles or traffics, and the molecular basis of its conserved neuronal function in mammals — remains undefined.","evidence":"","pmids":[],"confidence":"Low","gaps":["No identified direct physical substrate or interactor","No structural or domain-level mechanism","Mammalian (human MACO1) cellular function not characterized beyond ER localization"]}],"mechanism_profile":{"molecular_activity":[],"localization":[{"term_id":"GO:0005783","term_label":"endoplasmic reticulum","supporting_discovery_ids":[0,1]}],"pathway":[{"term_id":"R-HSA-112316","term_label":"Neuronal System","supporting_discovery_ids":[0,2]}],"complexes":[],"partners":[],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"Q8N5G2","full_name":"Macoilin","aliases":["Macoilin-1","Transmembrane protein 57"],"length_aa":664,"mass_kda":76.2,"function":"Plays a role in the regulation of neuronal activity","subcellular_location":"Nucleus membrane; Cell projection, axon; Rough endoplasmic reticulum membrane","url":"https://www.uniprot.org/uniprotkb/Q8N5G2/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/MACO1","classification":"Not Classified","n_dependent_lines":4,"n_total_lines":1208,"dependency_fraction":0.0033112582781456954},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[{"gene":"CERS6","stoichiometry":10.0},{"gene":"CERS5","stoichiometry":0.2},{"gene":"TMED10","stoichiometry":0.2},{"gene":"CCDC47","stoichiometry":0.2}],"url":"https://opencell.sf.czbiohub.org/search/MACO1","total_profiled":1310},"omim":[{"mim_id":"610301","title":"MACOILIN 1; MACO1","url":"https://www.omim.org/entry/610301"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Approved","locations":[{"location":"Cytosol","reliability":"Approved"}],"tissue_specificity":"Low tissue specificity","tissue_distribution":"Detected in all","driving_tissues":[],"url":"https://www.proteinatlas.org/search/MACO1"},"hgnc":{"alias_symbol":["FLJ10747"],"prev_symbol":["TMEM57"]},"alphafold":{"accession":"Q8N5G2","domains":[{"cath_id":"-","chopping":"23-200","consensus_level":"high","plddt":74.3501,"start":23,"end":200}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q8N5G2","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q8N5G2-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q8N5G2-F1-predicted_aligned_error_v6.png","plddt_mean":66.19},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=MACO1","jax_strain_url":"https://www.jax.org/strain/search?query=MACO1"},"sequence":{"accession":"Q8N5G2","fasta_url":"https://rest.uniprot.org/uniprotkb/Q8N5G2.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q8N5G2/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q8N5G2"}},"corpus_meta":[{"pmid":"32908307","id":"PMC_32908307","title":"C. elegans interprets bacterial non-coding RNAs to learn pathogenic avoidance.","date":"2020","source":"Nature","url":"https://pubmed.ncbi.nlm.nih.gov/32908307","citation_count":165,"is_preprint":false},{"pmid":"22291609","id":"PMC_22291609","title":"A genome-wide association scan on the levels of markers of inflammation in Sardinians reveals associations that underpin its complex regulation.","date":"2012","source":"PLoS genetics","url":"https://pubmed.ncbi.nlm.nih.gov/22291609","citation_count":130,"is_preprint":false},{"pmid":"21860704","id":"PMC_21860704","title":"Implications of discoveries from genome-wide association studies in current cardiovascular practice.","date":"2011","source":"World journal of cardiology","url":"https://pubmed.ncbi.nlm.nih.gov/21860704","citation_count":60,"is_preprint":false},{"pmid":"38547071","id":"PMC_38547071","title":"A natural bacterial pathogen of C. elegans uses a small RNA to induce transgenerational inheritance of learned avoidance.","date":"2024","source":"PLoS genetics","url":"https://pubmed.ncbi.nlm.nih.gov/38547071","citation_count":29,"is_preprint":false},{"pmid":"21437263","id":"PMC_21437263","title":"Macoilin, a conserved nervous system-specific ER membrane protein that regulates neuronal excitability.","date":"2011","source":"PLoS genetics","url":"https://pubmed.ncbi.nlm.nih.gov/21437263","citation_count":26,"is_preprint":false},{"pmid":"28924007","id":"PMC_28924007","title":"Multiple Signaling Pathways Coordinately Regulate Forgetting of Olfactory Adaptation through Control of Sensory Responses in Caenorhabditis elegans.","date":"2017","source":"The Journal of neuroscience : the official journal of the Society for Neuroscience","url":"https://pubmed.ncbi.nlm.nih.gov/28924007","citation_count":24,"is_preprint":false},{"pmid":"21589894","id":"PMC_21589894","title":"Novel and conserved protein macoilin is required for diverse neuronal functions in Caenorhabditis elegans.","date":"2011","source":"PLoS 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cohort.","date":"2013","source":"The pharmacogenomics journal","url":"https://pubmed.ncbi.nlm.nih.gov/23856853","citation_count":5,"is_preprint":false},{"pmid":"30275893","id":"PMC_30275893","title":"An efficient analytic approach in genome-wide identification of methylation quantitative trait loci response to fenofibrate treatment.","date":"2018","source":"BMC proceedings","url":"https://pubmed.ncbi.nlm.nih.gov/30275893","citation_count":3,"is_preprint":false},{"pmid":"40267186","id":"PMC_40267186","title":"C. elegans transgenerational avoidance of P. fluorescens is mediated by the Pfs1 sRNA and vab-1.","date":"2025","source":"Science advances","url":"https://pubmed.ncbi.nlm.nih.gov/40267186","citation_count":2,"is_preprint":false},{"pmid":"38826453","id":"PMC_38826453","title":"Pseudomonas fluorescens 15 small RNA Pfs1 mediates transgenerational epigenetic inheritance of pathogen avoidance in C. elegans through the Ephrin receptor VAB-1.","date":"2024","source":"bioRxiv : the preprint server for biology","url":"https://pubmed.ncbi.nlm.nih.gov/38826453","citation_count":2,"is_preprint":false},{"pmid":"37503135","id":"PMC_37503135","title":"A natural bacterial pathogen of C. elegans uses a small RNA to induce transgenerational inheritance of learned avoidance.","date":"2023","source":"bioRxiv : the preprint server for biology","url":"https://pubmed.ncbi.nlm.nih.gov/37503135","citation_count":1,"is_preprint":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":11740,"output_tokens":2245,"usd":0.034447,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":9349,"output_tokens":2620,"usd":0.056122,"stage2_stop_reason":"end_turn"},"total_usd":0.090569,"stage1_batch_id":"msgbatch_01BbTCMyrRPyhtEq6b1MdwCN","stage2_batch_id":"msgbatch_011dEed5bbxYvTAaQWKJevxu","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2011,\n      \"finding\": \"MACO-1 (macoilin) is expressed broadly and specifically in the nervous system of C. elegans and localizes to the rough endoplasmic reticulum; it is excluded from dendrites and axons. Loss of maco-1 causes resistance to the cholinesterase inhibitor aldicarb and sensitivity to levamisole, indicating pre-synaptic defects. In maco-1 mutants, the O2-sensing neuron PQR fails to generate Ca2+ responses to rising O2, a defect that mirrors mutations in egl-19 (L-type voltage-gated Ca2+ channel α1 subunit), leading to the conclusion that macoilin acts in the ER to regulate assembly or trafficking of ion channels or ion channel regulators.\",\n      \"method\": \"Fluorescent protein localization, in vivo Ca2+ imaging, pharmacological assays (aldicarb/levamisole), genetic epistasis with egl-19/nca-1/nca-2 mutants\",\n      \"journal\": \"PLoS genetics\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — multiple orthogonal methods (live imaging, pharmacology, genetic epistasis) in one study, independently replicated in a second concurrent publication (PMID:21589894)\",\n      \"pmids\": [\"21437263\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"Human macoilin (MACO1/TMEM57) and C. elegans MACO-1 both localize primarily to the rough endoplasmic reticulum. Expression of human macoilin in the C. elegans nervous system weakly rescues the thermotactic phenotype of maco-1 mutants, indicating functional conservation across species. maco-1 mutants show defective Ca2+ responses in AFD thermosensory neurons and AIY interneurons to thermal stimuli.\",\n      \"method\": \"Subcellular fractionation/localization, cross-species rescue by human MACO1 expression, in vivo Ca2+ imaging of AFD and AIY neurons\",\n      \"journal\": \"PLoS genetics\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — localization with functional consequence, cross-species rescue, Ca2+ imaging; replicates ER localization finding of PMID:21437263\",\n      \"pmids\": [\"21589894\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"MACO-1 functions downstream of the TIR-1/JNK-1 pathway to regulate forgetting of olfactory adaptation in C. elegans. Genetic screening identified maco-1 as a suppressor of the tir-1 gain-of-function excessive-forgetting phenotype. MACO-1 and the SCD-2/HEN-1 receptor tyrosine kinase–ligand pair act in parallel genetic pathways; only MACO-1 regulates forgetting of adaptation to isoamyl alcohol (sensed by different neuron types). Ca2+ imaging showed that odor-evoked Ca2+ response attenuation is sustained longer in maco-1 mutants, indicating that MACO-1 promotes recovery of sensory responses after conditioning.\",\n      \"method\": \"Forward genetic suppressor screen, double-mutant epistasis analysis, in vivo Ca2+ imaging, temporal neuronal silencing with histamine-gated chloride channels\",\n      \"journal\": \"The Journal of neuroscience\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genetic epistasis plus Ca2+ imaging, multiple orthogonal methods in single lab\",\n      \"pmids\": [\"28924007\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"maco-1 is required for pheromone-induced dauer formation in C. elegans, placing MACO-1 in the pathway for detection, transmission, or integration of ascaroside pheromone signals.\",\n      \"method\": \"Forward genetic screen (unbiased EMS mutagenesis), dauer formation assays\",\n      \"journal\": \"G3 (Bethesda, Md.)\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Weak — single genetic screen with phenotypic readout, no direct molecular mechanism established\",\n      \"pmids\": [\"26976437\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"The C. elegans gene maco-1 is the target of P. aeruginosa PA14 non-coding small RNA P11; knockdown/loss of maco-1 is required for bacterially-induced pathogen avoidance behavior and its transgenerational inheritance. The RNAi and piRNA pathways, the germline, and the ASI neuron are all required for this behavior, placing maco-1 downstream of a trans-kingdom sRNA silencing pathway.\",\n      \"method\": \"Bacterial sRNA purification and feeding, RNAi knockdown, loss-of-function genetics, behavioral assays (avoidance), epistasis with RNAi/piRNA pathway mutants\",\n      \"journal\": \"Nature\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — necessity and sufficiency of P11 sRNA shown, maco-1 loss-of-function required for avoidance, pathway placement via epistasis, replicated in subsequent independent studies\",\n      \"pmids\": [\"32908307\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"A P. vranovensis small RNA, Pv1, with 16-nt complementarity to an exon of C. elegans maco-1 is both necessary and sufficient to induce learned avoidance of P. vranovensis and its transgenerational inheritance, confirming that maco-1 downregulation by bacterial sRNAs is a conserved mechanism used by distinct Pseudomonas species.\",\n      \"method\": \"Bacterial sRNA sequencing, sRNA deletion and rescue (necessity/sufficiency), behavioral avoidance assays, transgenerational inheritance assays\",\n      \"journal\": \"PLoS genetics\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — necessity and sufficiency demonstrated with clean genetic experiments, independent replication of the maco-1 sRNA-targeting mechanism\",\n      \"pmids\": [\"38547071\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"VAB-1 loss reduces maco-1 expression, and knockdown of both vab-1 and maco-1 induces P. fluorescens avoidance, placing both genes in the same bacterial sRNA-targeted pathogenic avoidance pathway. This genetic interaction places MACO-1 downstream of or parallel to VAB-1 in the avoidance circuit.\",\n      \"method\": \"RNAi knockdown, genetic epistasis, expression analysis, behavioral avoidance assays\",\n      \"journal\": \"Science advances\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — epistasis and expression analysis in single lab, but mechanistic detail of MACO-1's placement relative to VAB-1 is based on expression level changes rather than direct biochemical interaction\",\n      \"pmids\": [\"40267186\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2002,\n      \"finding\": \"The mouse orthologue of FLJ10747 (MACO1) shows slightly higher expression in testis relative to other tissues, and subcellular localization experiments indicate a strong nuclear localization, in contrast to SMP1 which is cytoplasmic.\",\n      \"method\": \"Tissue distribution analysis, subcellular localization by genomic/expression analysis of syntenic region\",\n      \"journal\": \"Gene\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — single study, method details minimal in abstract, only localization reported with no functional consequence described\",\n      \"pmids\": [\"12459264\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"MACO1 (macoilin/TMEM57) encodes a conserved multi-transmembrane ER-resident protein expressed specifically in neurons, where it acts within the endoplasmic reticulum to regulate ion channel assembly or trafficking (particularly involving the L-type Ca2+ channel EGL-19), thereby controlling neuronal excitability, sensory Ca2+ responses, and behaviors including O2 sensing, thermotaxis, olfactory adaptation forgetting, and pheromone-induced dauer formation; in C. elegans, maco-1 is also the molecular target of bacterial pathogen-derived small RNAs (PA14-P11, Pv1) that silence its expression via the RNAi/piRNA pathway to induce transgenerational learned avoidance of pathogens.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"MACO1 (macoilin/TMEM57) encodes a conserved multi-transmembrane protein of the rough endoplasmic reticulum that is expressed broadly and specifically in the nervous system, where it controls neuronal excitability and sensory signaling [#0, #1]. In C. elegans, loss of maco-1 produces presynaptic neurotransmission defects (aldicarb resistance, levamisole sensitivity) and abolishes the rising-O2 Ca2+ response of the PQR sensory neuron in a manner mirroring mutation of the L-type voltage-gated Ca2+ channel α1 subunit egl-19, supporting a model in which macoilin acts within the ER to regulate the assembly or trafficking of ion channels or their regulators [#0]. ER localization and a neuronal function are conserved: human MACO1 localizes to the rough ER and weakly rescues the thermotaxis defect of maco-1 mutants, which themselves show altered thermosensory Ca2+ responses in AFD and AIY neurons [#1]. Through this control of sensory Ca2+ dynamics, MACO-1 acts downstream of the TIR-1/JNK-1 pathway to promote recovery of attenuated odor-evoked responses, thereby driving forgetting of olfactory adaptation, and is also required for pheromone-induced dauer formation [#2, #3]. Independently, maco-1 is the molecular endpoint of a trans-kingdom small-RNA silencing mechanism: small RNAs from Pseudomonas species (PA14-derived P11; P. vranovensis Pv1) bear complementarity to maco-1 and downregulate it via the RNAi/piRNA pathway to drive learned, transgenerationally inherited pathogen avoidance, a circuit in which maco-1 acts downstream of or parallel to the VAB-1 receptor [#4, #5, #6].\",\n  \"teleology\": [\n    {\n      \"year\": 2011,\n      \"claim\": \"Established macoilin as a neuron-specific rough-ER protein whose loss disrupts presynaptic function and sensory Ca2+ responses, generating the model that it regulates ion channel assembly/trafficking from the ER.\",\n      \"evidence\": \"Fluorescent localization, in vivo Ca2+ imaging of PQR, aldicarb/levamisole pharmacology, and genetic epistasis with egl-19/nca-1/nca-2 in C. elegans\",\n      \"pmids\": [\"21437263\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"No direct biochemical demonstration that macoilin binds or chaperones EGL-19 or other channels\", \"Mechanism distinguishing assembly versus trafficking not resolved\"]\n    },\n    {\n      \"year\": 2011,\n      \"claim\": \"Demonstrated cross-species conservation of ER localization and neuronal function, showing human MACO1 can substitute for the worm protein in thermotaxis.\",\n      \"evidence\": \"Subcellular localization, cross-species rescue by human MACO1 expression, and Ca2+ imaging of AFD/AIY neurons\",\n      \"pmids\": [\"21589894\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Rescue was only weak/partial\", \"Human MACO1 molecular activity not directly assayed in a mammalian system\"]\n    },\n    {\n      \"year\": 2016,\n      \"claim\": \"Placed MACO-1 in pheromone signaling by showing it is required for ascaroside-pheromone-induced dauer formation.\",\n      \"evidence\": \"Forward EMS genetic screen and dauer formation assays in C. elegans\",\n      \"pmids\": [\"26976437\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No molecular mechanism linking MACO-1 to pheromone detection/integration\", \"Site of action within the dauer pathway undefined\"]\n    },\n    {\n      \"year\": 2017,\n      \"claim\": \"Connected MACO-1 to a defined signaling pathway by showing it acts downstream of TIR-1/JNK-1 to promote recovery of sensory Ca2+ responses and forgetting of olfactory adaptation.\",\n      \"evidence\": \"Forward suppressor screen, double-mutant epistasis, in vivo Ca2+ imaging, and histamine-gated chloride channel neuronal silencing\",\n      \"pmids\": [\"28924007\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"How ER-localized MACO-1 mechanistically restores Ca2+ response recovery is unknown\", \"Relationship between this role and channel trafficking not established\"]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"Identified maco-1 as the silencing target of a bacterial non-coding small RNA, defining it as the genetic endpoint of a trans-kingdom RNAi/piRNA pathway driving heritable pathogen avoidance.\",\n      \"evidence\": \"PA14 sRNA purification and feeding, RNAi knockdown, loss-of-function genetics, and behavioral/transgenerational assays with RNAi/piRNA pathway epistasis\",\n      \"pmids\": [\"32908307\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"How reduced MACO-1 in specific neurons translates to avoidance behavior not mechanistically resolved\", \"Link between ER/channel function and avoidance circuit not established\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Generalized the sRNA-targeting mechanism by showing a distinct Pseudomonas species uses an independent small RNA (Pv1) complementary to maco-1 to induce heritable avoidance.\",\n      \"evidence\": \"Bacterial sRNA sequencing, sRNA deletion/rescue for necessity and sufficiency, and transgenerational avoidance assays\",\n      \"pmids\": [\"38547071\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Whether other pathogens converge on maco-1 broadly unknown\", \"Downstream consequences of maco-1 downregulation on neuronal physiology not measured\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Positioned MACO-1 relative to the VAB-1 receptor within the avoidance circuit, showing VAB-1 loss reduces maco-1 expression and combined knockdown induces avoidance.\",\n      \"evidence\": \"RNAi knockdown, genetic epistasis, expression analysis, and behavioral avoidance assays\",\n      \"pmids\": [\"40267186\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Placement inferred from expression-level changes, not direct biochemical interaction\", \"Whether VAB-1 regulates maco-1 directly or indirectly unknown\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"The biochemical activity of macoilin at the ER — its direct binding partners, the channels it assembles or traffics, and the molecular basis of its conserved neuronal function in mammals — remains undefined.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Low\",\n      \"gaps\": [\"No identified direct physical substrate or interactor\", \"No structural or domain-level mechanism\", \"Mammalian (human MACO1) cellular function not characterized beyond ER localization\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [],\n    \"localization\": [\n      {\"term_id\": \"GO:0005783\", \"supporting_discovery_ids\": [0, 1]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-112316\", \"supporting_discovery_ids\": [0, 2]}\n    ],\n    \"complexes\": [],\n    \"partners\": [],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"faith_supported":5,"faith_total":5,"faith_pct":100.0}}