{"gene":"NALF1","run_date":"2026-06-10T05:19:52","timeline":{"discoveries":[{"year":2013,"finding":"NLF-1 (NALF1 ortholog in C. elegans) is a conserved endoplasmic reticulum (ER) protein that promotes axonal localization of all NCA (NALCN) channel reporters; loss of NLF-1 reduces sodium leak current and hyperpolarizes resting membrane potential in premotor interneurons, decreasing rhythmic locomotion initiation.","method":"Loss-of-function genetics in C. elegans, electrophysiology (sodium leak current measurement), fluorescent reporter localization, behavioral assays","journal":"Neuron","confidence":"High","confidence_rationale":"Tier 2 / Strong — multiple orthogonal methods (electrophysiology, live imaging, behavioral assays, genetic epistasis) in a single rigorous study with clear mechanistic readouts","pmids":["23522043"],"is_preprint":false},{"year":2013,"finding":"Mouse NLF-1 (mNLF-1/FAM155A) functionally substitutes for C. elegans NLF-1 in vivo, physically interacts with the mammalian sodium leak channel NALCN in vitro, and potentiates sodium leak currents in primary cortical neuron cultures.","method":"Heterologous rescue in C. elegans, in vitro binding/pulldown assay, electrophysiology in primary cortical neuron cultures","journal":"Neuron","confidence":"High","confidence_rationale":"Tier 1-2 / Strong — in vitro interaction assay combined with functional electrophysiology and cross-species genetic rescue, multiple orthogonal methods in one study","pmids":["23522043"],"is_preprint":false},{"year":2020,"finding":"Robust functional expression of NALCN in heterologous systems requires co-expression of UNC79, UNC80, and FAM155A; the resulting NALCN channel complex is constitutively active, conducts monovalent cations, is blocked by extracellular divalent cations, and is modulated by membrane voltage.","method":"Heterologous expression with co-transfection, electrophysiology (whole-cell patch clamp), pharmacological manipulation of extracellular Ca2+","journal":"Science advances","confidence":"High","confidence_rationale":"Tier 1 / Moderate — reconstituted functional channel complex in heterologous system with electrophysiology and pharmacology; single lab but multiple orthogonal functional readouts","pmids":["32494638"],"is_preprint":false},{"year":2020,"finding":"Cryo-EM structure of rat NALCN and mouse FAM155A complex at 2.7 Å resolution reveals that FAM155A contacts NALCN via its extracellular cysteine-rich domain; the non-canonical selectivity filter of NALCN dictates sodium selectivity and calcium block; asymmetric voltage sensors confer voltage modulation.","method":"Cryo-EM structure determination at 2.7 Å resolution, structure-function analysis mapping disease mutations to domain interfaces","journal":"Nature communications","confidence":"High","confidence_rationale":"Tier 1 / Moderate — near-atomic cryo-EM structure with mechanistic interpretation of selectivity filter and voltage sensors; single lab but rigorous structural method","pmids":["33273469"],"is_preprint":false},{"year":2022,"finding":"Cryo-EM structure of the mammalian NALCN-FAM155A-UNC79-UNC80 quaternary complex reveals that UNC79-UNC80 form a large piler-shaped heterodimer tethered to NALCN intracellular loops via tripartite interactions; two of these interactions are essential for NALCN cell surface localization; one interaction relieves NALCN self-inhibition by displacing the auto-inhibitory CTD Interacting Helix (CIH) from its binding site.","method":"Cryo-EM structure determination of heterotetrameric complex, mutagenesis of interaction interfaces, cell surface localization assays","journal":"Nature communications","confidence":"High","confidence_rationale":"Tier 1 / Strong — cryo-EM structure combined with mutagenesis and functional localization assays defining specific molecular interactions and mechanism of NALCN modulation","pmids":["35550517"],"is_preprint":false},{"year":2017,"finding":"In Drosophila, developmental expression of Nlf-1 (NALF1 ortholog) is sufficient to promote robust rhythmic behavioral activity in adults; the NA/NALCN channel complex proteins produced during development persist in the adult brain with little decay for at least 5–7 days, indicating the channel complex is highly stable and that circadian regulation of NA channel function is mediated primarily by post-translational mechanisms independent of Nlf-1.","method":"Temperature-inducible tubulin-GAL80ts system for temporally restricted gene expression, behavioral rhythmicity assays, protein persistence assays in Drosophila head","journal":"Frontiers in cellular neuroscience","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — genetic temporal restriction with behavioral and biochemical readouts; single lab, two orthogonal approaches (behavior + protein stability)","pmids":["28634443"],"is_preprint":false},{"year":2025,"finding":"NALF1 protein is preferentially translated (not transcriptionally upregulated) in dorsal root ganglion neurons in a mouse model of paclitaxel-induced neuropathic pain; this translational upregulation is mediated by the RNA-binding protein HNRNP L, which binds a 14-base CA-rich element (CARE) in the Nalf1 3' UTR; genetic elimination of HNRNP L, the CARE motif, or the pore-forming NALCN subunit reduces pain amplification in vivo.","method":"Ribosome profiling (functional genomics), RNA-binding protein pulldown (HNRNP L binding to CARE), genetic knockout/CARE motif deletion in mice, behavioral pain assays","journal":"Pain","confidence":"High","confidence_rationale":"Tier 1-2 / Moderate — ribosome profiling identifying translational regulation, direct RNA-binding assay identifying CARE element, and in vivo genetic validation with functional pain readout; multiple orthogonal methods in single study","pmids":["40839605"],"is_preprint":false}],"current_model":"NALF1 (NLF-1/FAM155A) is an ER-resident extracellular/membrane-associated protein that forms the core complex with the NALCN sodium leak channel; it is required for proper trafficking and axonal/cell-surface localization of NALCN, potentiates sodium leak currents to maintain neuronal resting membrane potential, and its cryo-EM structure shows it contacts NALCN via a cysteine-rich extracellular domain; within the full NALCN-FAM155A-UNC79-UNC80 quaternary complex, UNC79-UNC80 relieve NALCN self-inhibition through interactions that depend on FAM155A-stabilized channel assembly; additionally, NALF1 translation in sensory neurons is post-transcriptionally regulated by HNRNP L via a 3' UTR CARE element, contributing to neuropathic pain."},"narrative":{"mechanistic_narrative":"NALF1 (NLF-1/FAM155A) is a conserved endoplasmic reticulum protein that functions as an obligate auxiliary subunit of the NALCN sodium leak channel, governing its trafficking and the sodium leak conductance that sets neuronal resting membrane potential [PMID:23522043]. First defined through its C. elegans ortholog NLF-1, the protein promotes axonal localization of NALCN channel reporters, and its loss reduces sodium leak current, hyperpolarizes premotor interneurons, and impairs rhythmic locomotion; the mouse ortholog rescues this defect, binds NALCN directly, and potentiates leak currents in cortical neurons [PMID:23522043]. Robust functional reconstitution of the constitutively active, monovalent-cation-conducting NALCN channel requires co-expression of FAM155A together with UNC79 and UNC80 [PMID:32494638]. Structurally, FAM155A contacts NALCN through its extracellular cysteine-rich domain, while UNC79-UNC80 form a heterodimer tethered to NALCN intracellular loops via tripartite interactions that are required for channel cell-surface localization and that relieve NALCN self-inhibition by displacing the auto-inhibitory CTD-interacting helix [PMID:33273469, PMID:35550517]. Beyond its channel role, Nalf1 expression is regulated post-transcriptionally: in dorsal root ganglion neurons, the RNA-binding protein HNRNP L binds a CA-rich element (CARE) in the Nalf1 3' UTR to drive preferential translation, and disrupting HNRNP L, the CARE motif, or NALCN reduces paclitaxel-induced neuropathic pain amplification [PMID:40839605].","teleology":[{"year":2013,"claim":"Established that NALF1 is an ER protein required for proper localization and function of the NALCN sodium leak channel, linking it causally to resting membrane potential and rhythmic behavior.","evidence":"Loss-of-function genetics, electrophysiology, reporter imaging, and behavioral assays in C. elegans, with cross-species heterologous rescue and in vitro binding plus electrophysiology for the mammalian ortholog","pmids":["23522043"],"confidence":"High","gaps":["The structural basis of the NALF1-NALCN interaction was not defined","How the ER-resident protein chaperones NALCN to the axon was not resolved at the molecular level"]},{"year":2017,"claim":"Showed that the NALCN/NALF1 channel complex is highly stable once assembled during development, implying that NALF1 acts in channel biogenesis rather than ongoing circadian modulation.","evidence":"Temperature-inducible temporal gene expression (GAL80ts), behavioral rhythmicity, and protein persistence assays in Drosophila","pmids":["28634443"],"confidence":"Medium","gaps":["Single-organism (Drosophila) finding not extended to mammalian channel turnover","The post-translational mechanisms that modulate the stable complex were not identified"]},{"year":2020,"claim":"Defined the minimal subunit requirements and biophysical properties of the functional NALCN complex, and resolved how FAM155A physically engages NALCN.","evidence":"Heterologous reconstitution with co-transfection and whole-cell patch clamp plus pharmacology; 2.7 Å cryo-EM structure of the rat NALCN-mouse FAM155A complex","pmids":["32494638","33273469"],"confidence":"High","gaps":["The structure captured NALCN-FAM155A without UNC79/UNC80, leaving the full assembly mechanism unresolved","How FAM155A's cysteine-rich domain contributes mechanistically to trafficking versus gating was not separated"]},{"year":2022,"claim":"Resolved the full quaternary complex and the mechanism by which auxiliary subunits control NALCN surface delivery and relieve its auto-inhibition.","evidence":"Cryo-EM of the NALCN-FAM155A-UNC79-UNC80 heterotetramer with interface mutagenesis and cell surface localization assays","pmids":["35550517"],"confidence":"High","gaps":["The dynamics of how the auto-inhibitory CIH is displaced during gating were not captured","FAM155A's specific contribution to relieving self-inhibition relative to UNC79-UNC80 was not isolated"]},{"year":2025,"claim":"Identified a post-transcriptional regulatory mechanism controlling NALF1 abundance in pain signaling, connecting it to neuropathic pain amplification.","evidence":"Ribosome profiling, RNA-binding protein pulldown mapping HNRNP L to a 3' UTR CARE element, and genetic knockout/CARE deletion with behavioral pain assays in mice","pmids":["40839605"],"confidence":"High","gaps":["Whether translational control of NALF1 alters NALCN surface levels in DRG neurons was not directly shown","The signaling that activates HNRNP L-mediated translation upon nerve injury was not defined"]},{"year":null,"claim":"How NALF1 mechanistically couples its ER residence and cysteine-rich extracellular domain to NALCN folding, surface trafficking, and gating remains incompletely separated from the contributions of UNC79/UNC80.","evidence":"","pmids":[],"confidence":"High","gaps":["No structure of NALF1 acting at the ER during NALCN biogenesis","The trafficking itinerary that delivers the complex to the axon is uncharacterized"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0098772","term_label":"molecular function regulator activity","supporting_discovery_ids":[1,2,4]}],"localization":[{"term_id":"GO:0005783","term_label":"endoplasmic reticulum","supporting_discovery_ids":[0]},{"term_id":"GO:0005886","term_label":"plasma membrane","supporting_discovery_ids":[3,4]}],"pathway":[{"term_id":"R-HSA-112316","term_label":"Neuronal System","supporting_discovery_ids":[0,1]}],"complexes":["NALCN-FAM155A-UNC79-UNC80 channel complex"],"partners":["NALCN","UNC79","UNC80","HNRNPL"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"B1AL88","full_name":"NALCN channel auxiliary factor 1","aliases":["Transmembrane protein FAM155A"],"length_aa":458,"mass_kda":51.5,"function":"Auxillary component of the NALCN sodium channel complex, a channel that regulates the resting membrane potential and controls neuronal excitability","subcellular_location":"Cell membrane","url":"https://www.uniprot.org/uniprotkb/B1AL88/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/NALF1","classification":"Not Classified","n_dependent_lines":2,"n_total_lines":1208,"dependency_fraction":0.0016556291390728477},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[],"url":"https://opencell.sf.czbiohub.org/search/NALF1","total_profiled":1310},"omim":[{"mim_id":"619899","title":"NALCN CHANNEL AUXILIARY FACTOR 1; NALF1","url":"https://www.omim.org/entry/619899"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"","locations":[],"tissue_specificity":"Tissue enhanced","tissue_distribution":"Detected in some","driving_tissues":[{"tissue":"brain","ntpm":8.5},{"tissue":"pituitary gland","ntpm":4.8}],"url":"https://www.proteinatlas.org/search/NALF1"},"hgnc":{"alias_symbol":["NLF-1"],"prev_symbol":["FAM155A"]},"alphafold":{"accession":"B1AL88","domains":[{"cath_id":"-","chopping":"169-192_216-378","consensus_level":"medium","plddt":76.7524,"start":169,"end":378}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/B1AL88","model_url":"https://alphafold.ebi.ac.uk/files/AF-B1AL88-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-B1AL88-F1-predicted_aligned_error_v6.png","plddt_mean":61.22},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=NALF1","jax_strain_url":"https://www.jax.org/strain/search?query=NALF1"},"sequence":{"accession":"B1AL88","fasta_url":"https://rest.uniprot.org/uniprotkb/B1AL88.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/B1AL88/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/B1AL88"}},"corpus_meta":[{"pmid":"24904279","id":"PMC_24904279","title":"The sodium leak channel, NALCN, 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Non-coding RNA Expression in Finnish and Russian Karelia Teenagers With Contrasting Risk of Allergy and Asthma.","date":"2022","source":"Frontiers in allergy","url":"https://pubmed.ncbi.nlm.nih.gov/35769561","citation_count":6,"is_preprint":false},{"pmid":"37067163","id":"PMC_37067163","title":"Novel nonsense mutation in UNC80 in a Turkish patient further validates the sociable skill and severe gastrointestinal problems as part of disease spectrum.","date":"2023","source":"American journal of medical genetics. 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loss of NLF-1 reduces sodium leak current and hyperpolarizes resting membrane potential in premotor interneurons, decreasing rhythmic locomotion initiation.\",\n      \"method\": \"Loss-of-function genetics in C. elegans, electrophysiology (sodium leak current measurement), fluorescent reporter localization, behavioral assays\",\n      \"journal\": \"Neuron\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — multiple orthogonal methods (electrophysiology, live imaging, behavioral assays, genetic epistasis) in a single rigorous study with clear mechanistic readouts\",\n      \"pmids\": [\"23522043\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"Mouse NLF-1 (mNLF-1/FAM155A) functionally substitutes for C. elegans NLF-1 in vivo, physically interacts with the mammalian sodium leak channel NALCN in vitro, and potentiates sodium leak currents in primary cortical neuron cultures.\",\n      \"method\": \"Heterologous rescue in C. elegans, in vitro binding/pulldown assay, electrophysiology in primary cortical neuron cultures\",\n      \"journal\": \"Neuron\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 / Strong — in vitro interaction assay combined with functional electrophysiology and cross-species genetic rescue, multiple orthogonal methods in one study\",\n      \"pmids\": [\"23522043\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"Robust functional expression of NALCN in heterologous systems requires co-expression of UNC79, UNC80, and FAM155A; the resulting NALCN channel complex is constitutively active, conducts monovalent cations, is blocked by extracellular divalent cations, and is modulated by membrane voltage.\",\n      \"method\": \"Heterologous expression with co-transfection, electrophysiology (whole-cell patch clamp), pharmacological manipulation of extracellular Ca2+\",\n      \"journal\": \"Science advances\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — reconstituted functional channel complex in heterologous system with electrophysiology and pharmacology; single lab but multiple orthogonal functional readouts\",\n      \"pmids\": [\"32494638\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"Cryo-EM structure of rat NALCN and mouse FAM155A complex at 2.7 Å resolution reveals that FAM155A contacts NALCN via its extracellular cysteine-rich domain; the non-canonical selectivity filter of NALCN dictates sodium selectivity and calcium block; asymmetric voltage sensors confer voltage modulation.\",\n      \"method\": \"Cryo-EM structure determination at 2.7 Å resolution, structure-function analysis mapping disease mutations to domain interfaces\",\n      \"journal\": \"Nature communications\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — near-atomic cryo-EM structure with mechanistic interpretation of selectivity filter and voltage sensors; single lab but rigorous structural method\",\n      \"pmids\": [\"33273469\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"Cryo-EM structure of the mammalian NALCN-FAM155A-UNC79-UNC80 quaternary complex reveals that UNC79-UNC80 form a large piler-shaped heterodimer tethered to NALCN intracellular loops via tripartite interactions; two of these interactions are essential for NALCN cell surface localization; one interaction relieves NALCN self-inhibition by displacing the auto-inhibitory CTD Interacting Helix (CIH) from its binding site.\",\n      \"method\": \"Cryo-EM structure determination of heterotetrameric complex, mutagenesis of interaction interfaces, cell surface localization assays\",\n      \"journal\": \"Nature communications\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — cryo-EM structure combined with mutagenesis and functional localization assays defining specific molecular interactions and mechanism of NALCN modulation\",\n      \"pmids\": [\"35550517\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"In Drosophila, developmental expression of Nlf-1 (NALF1 ortholog) is sufficient to promote robust rhythmic behavioral activity in adults; the NA/NALCN channel complex proteins produced during development persist in the adult brain with little decay for at least 5–7 days, indicating the channel complex is highly stable and that circadian regulation of NA channel function is mediated primarily by post-translational mechanisms independent of Nlf-1.\",\n      \"method\": \"Temperature-inducible tubulin-GAL80ts system for temporally restricted gene expression, behavioral rhythmicity assays, protein persistence assays in Drosophila head\",\n      \"journal\": \"Frontiers in cellular neuroscience\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genetic temporal restriction with behavioral and biochemical readouts; single lab, two orthogonal approaches (behavior + protein stability)\",\n      \"pmids\": [\"28634443\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"NALF1 protein is preferentially translated (not transcriptionally upregulated) in dorsal root ganglion neurons in a mouse model of paclitaxel-induced neuropathic pain; this translational upregulation is mediated by the RNA-binding protein HNRNP L, which binds a 14-base CA-rich element (CARE) in the Nalf1 3' UTR; genetic elimination of HNRNP L, the CARE motif, or the pore-forming NALCN subunit reduces pain amplification in vivo.\",\n      \"method\": \"Ribosome profiling (functional genomics), RNA-binding protein pulldown (HNRNP L binding to CARE), genetic knockout/CARE motif deletion in mice, behavioral pain assays\",\n      \"journal\": \"Pain\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 / Moderate — ribosome profiling identifying translational regulation, direct RNA-binding assay identifying CARE element, and in vivo genetic validation with functional pain readout; multiple orthogonal methods in single study\",\n      \"pmids\": [\"40839605\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"NALF1 (NLF-1/FAM155A) is an ER-resident extracellular/membrane-associated protein that forms the core complex with the NALCN sodium leak channel; it is required for proper trafficking and axonal/cell-surface localization of NALCN, potentiates sodium leak currents to maintain neuronal resting membrane potential, and its cryo-EM structure shows it contacts NALCN via a cysteine-rich extracellular domain; within the full NALCN-FAM155A-UNC79-UNC80 quaternary complex, UNC79-UNC80 relieve NALCN self-inhibition through interactions that depend on FAM155A-stabilized channel assembly; additionally, NALF1 translation in sensory neurons is post-transcriptionally regulated by HNRNP L via a 3' UTR CARE element, contributing to neuropathic pain.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"NALF1 (NLF-1/FAM155A) is a conserved endoplasmic reticulum protein that functions as an obligate auxiliary subunit of the NALCN sodium leak channel, governing its trafficking and the sodium leak conductance that sets neuronal resting membrane potential [#0, #1]. First defined through its C. elegans ortholog NLF-1, the protein promotes axonal localization of NALCN channel reporters, and its loss reduces sodium leak current, hyperpolarizes premotor interneurons, and impairs rhythmic locomotion; the mouse ortholog rescues this defect, binds NALCN directly, and potentiates leak currents in cortical neurons [#0, #1]. Robust functional reconstitution of the constitutively active, monovalent-cation-conducting NALCN channel requires co-expression of FAM155A together with UNC79 and UNC80 [#2]. Structurally, FAM155A contacts NALCN through its extracellular cysteine-rich domain, while UNC79-UNC80 form a heterodimer tethered to NALCN intracellular loops via tripartite interactions that are required for channel cell-surface localization and that relieve NALCN self-inhibition by displacing the auto-inhibitory CTD-interacting helix [#3, #4]. Beyond its channel role, Nalf1 expression is regulated post-transcriptionally: in dorsal root ganglion neurons, the RNA-binding protein HNRNP L binds a CA-rich element (CARE) in the Nalf1 3' UTR to drive preferential translation, and disrupting HNRNP L, the CARE motif, or NALCN reduces paclitaxel-induced neuropathic pain amplification [#6].\",\n  \"teleology\": [\n    {\n      \"year\": 2013,\n      \"claim\": \"Established that NALF1 is an ER protein required for proper localization and function of the NALCN sodium leak channel, linking it causally to resting membrane potential and rhythmic behavior.\",\n      \"evidence\": \"Loss-of-function genetics, electrophysiology, reporter imaging, and behavioral assays in C. elegans, with cross-species heterologous rescue and in vitro binding plus electrophysiology for the mammalian ortholog\",\n      \"pmids\": [\"23522043\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"The structural basis of the NALF1-NALCN interaction was not defined\",\n        \"How the ER-resident protein chaperones NALCN to the axon was not resolved at the molecular level\"\n      ]\n    },\n    {\n      \"year\": 2017,\n      \"claim\": \"Showed that the NALCN/NALF1 channel complex is highly stable once assembled during development, implying that NALF1 acts in channel biogenesis rather than ongoing circadian modulation.\",\n      \"evidence\": \"Temperature-inducible temporal gene expression (GAL80ts), behavioral rhythmicity, and protein persistence assays in Drosophila\",\n      \"pmids\": [\"28634443\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"Single-organism (Drosophila) finding not extended to mammalian channel turnover\",\n        \"The post-translational mechanisms that modulate the stable complex were not identified\"\n      ]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"Defined the minimal subunit requirements and biophysical properties of the functional NALCN complex, and resolved how FAM155A physically engages NALCN.\",\n      \"evidence\": \"Heterologous reconstitution with co-transfection and whole-cell patch clamp plus pharmacology; 2.7 Å cryo-EM structure of the rat NALCN-mouse FAM155A complex\",\n      \"pmids\": [\"32494638\", \"33273469\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"The structure captured NALCN-FAM155A without UNC79/UNC80, leaving the full assembly mechanism unresolved\",\n        \"How FAM155A's cysteine-rich domain contributes mechanistically to trafficking versus gating was not separated\"\n      ]\n    },\n    {\n      \"year\": 2022,\n      \"claim\": \"Resolved the full quaternary complex and the mechanism by which auxiliary subunits control NALCN surface delivery and relieve its auto-inhibition.\",\n      \"evidence\": \"Cryo-EM of the NALCN-FAM155A-UNC79-UNC80 heterotetramer with interface mutagenesis and cell surface localization assays\",\n      \"pmids\": [\"35550517\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"The dynamics of how the auto-inhibitory CIH is displaced during gating were not captured\",\n        \"FAM155A's specific contribution to relieving self-inhibition relative to UNC79-UNC80 was not isolated\"\n      ]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Identified a post-transcriptional regulatory mechanism controlling NALF1 abundance in pain signaling, connecting it to neuropathic pain amplification.\",\n      \"evidence\": \"Ribosome profiling, RNA-binding protein pulldown mapping HNRNP L to a 3' UTR CARE element, and genetic knockout/CARE deletion with behavioral pain assays in mice\",\n      \"pmids\": [\"40839605\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Whether translational control of NALF1 alters NALCN surface levels in DRG neurons was not directly shown\",\n        \"The signaling that activates HNRNP L-mediated translation upon nerve injury was not defined\"\n      ]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How NALF1 mechanistically couples its ER residence and cysteine-rich extracellular domain to NALCN folding, surface trafficking, and gating remains incompletely separated from the contributions of UNC79/UNC80.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"No structure of NALF1 acting at the ER during NALCN biogenesis\",\n        \"The trafficking itinerary that delivers the complex to the axon is uncharacterized\"\n      ]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0098772\", \"supporting_discovery_ids\": [1, 2, 4]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005783\", \"supporting_discovery_ids\": [0]},\n      {\"term_id\": \"GO:0005886\", \"supporting_discovery_ids\": [3, 4]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-112316\", \"supporting_discovery_ids\": [0, 1]}\n    ],\n    \"complexes\": [\n      \"NALCN-FAM155A-UNC79-UNC80 channel complex\"\n    ],\n    \"partners\": [\n      \"NALCN\",\n      \"UNC79\",\n      \"UNC80\",\n      \"HNRNPL\"\n    ],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":5,"faith_total":5,"faith_pct":100.0}}