{"gene":"PF3D7_1017500","run_date":"2026-09-08T12:51:28","timeline":{"discoveries":[{"year":2017,"finding":"ELC (PF3D7_1017500) was identified as an additional myosin light chain component of the P. berghei glideosome complex; it binds the MyoA neck region adjacent to the MTIP-binding site, and co-localizes with MTIP to the glideosome. Co-expression of MyoA with both light chains (ELC and MTIP) enhances MyoA-dependent actin motility compared to MyoA with MTIP alone.","method":"Co-immunoprecipitation/co-purification from parasite lysates, live imaging of P. berghei stages, in vitro actin gliding assay with recombinant proteins","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 1–2 / Strong — binding site mapping, localization, and functional motility assay all reported; independently corroborated in the companion paper (PMID:28978649)","pmids":["28893907"],"is_preprint":false,"attribution":[{"species":"Plasmodium berghei","strain":""},{"species":"Plasmodium falciparum","strain":""}]},{"year":2017,"finding":"PfELC (PF3D7_1017500) co-purified with PfMyoA isolated from P. falciparum parasite lysates, confirming it is a bona fide light chain of PfMyoA. Crucially, PfELC binding to the PfMyoA heavy chain required that MTIP also be bound; unlike MTIP, PfELC cannot bind the heavy chain independently. Actin gliding speed was fastest when both PfELC and MTIP were present, consistent with the light-chain-binding domain acting as a lever arm to amplify motor domain motions.","method":"Baculovirus/Sf9 recombinant expression, co-purification, in vitro actin gliding assay, deletion mutant analysis","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 1 / Strong — reconstitution in vitro with purified recombinant proteins, mutagenesis/deletion analysis, functional motility assay; replicated across two concurrent studies","pmids":["28978649"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2020,"finding":"Crystal structure of PfELC (PF3D7_1017500) as part of a trimeric sub-complex with PfMyoA reveals that PfELC adopts a distinct structure in its free versus MyoA-bound state, and that it binds a conserved IQ motif on MyoA. Structural and biophysical analysis demonstrated that calcium binding has no influence on the structure of PfELC. The ELC is proposed to stiffen the MyoA lever arm by inducing secondary structure in MyoA.","method":"X-ray crystallography of trimeric sub-complex, biophysical analysis (SAXS), comparative structural analysis with Toxoplasma ELC","journal":"Communications biology","confidence":"High","confidence_rationale":"Tier 1 / Moderate — crystal structure with functional inference; calcium-independence validated biophysically; single lab but multiple orthogonal structural methods","pmids":["33051581"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2020,"finding":"Full-length cryo-EM/crystal structures of PfMyoA in two motor-cycle states revealed the mode of recognition of PfELC (PF3D7_1017500) by a degenerate IQ motif on the PfMyoA lever arm. Kinetic and motility assays with PfMyoA variants demonstrated that PfELC contributes to tuning the motor's mechano-chemical properties. Conditional genetic disruption of PfELC in P. falciparum merozoites provided evidence for an essential role of PfELC in malaria pathogenesis.","method":"X-ray crystallography (full-length PfMyoA structures in two states), molecular dynamics, kinetic ATPase assays, actin gliding assay with PfMyoA variants, conditional genetic mutagenesis in P. falciparum","journal":"eLife","confidence":"High","confidence_rationale":"Tier 1 / Strong — crystal structure plus kinetic assays plus in-parasite conditional mutagenesis; multiple orthogonal methods in single rigorous study","pmids":["33046215"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2020,"finding":"Conditional genetic disruption of PfELC (PF3D7_1017500) in P. falciparum merozoites produced a distinct incomplete-invasion phenotype, defining one of three energetic barriers to successful RBC entry (mid-invasion initiation). This established that ELC-dependent motor force is required at a specific stage of merozoite invasion.","method":"Conditional mutagenesis (DiCre-based), live video microscopy of invasion, quantitative invasion assay","journal":"PLoS pathogens","confidence":"High","confidence_rationale":"Tier 2 / Moderate — conditional KO with live imaging and quantitative phenotypic readout; single lab but rigorous genetic approach with multiple control mutants","pmids":["33104759"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2022,"finding":"High-resolution cryo-EM structure of the P. falciparum actomyosin complex visualized PfELC (PF3D7_1017500) bound to the PfMyoA light-chain-binding region alongside PfMTIP, providing atomic-level detail of the PfAct1:PfMyoA interface and lower-resolution visualization of the two-light-chain arrangement.","method":"Cryo-EM structure determination of reconstituted actomyosin complex","journal":"PLoS pathogens","confidence":"Medium","confidence_rationale":"Tier 1 / Weak — high-resolution structure but PfELC region resolved only at lower resolution; single study","pmids":["35377914"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]}],"current_model":"PfELC (PF3D7_1017500) is an essential myosin light chain of the Plasmodium glideosome that binds a degenerate IQ motif on the PfMyoA lever arm in a MTIP-dependent manner, stiffens the lever arm to enhance motor stroke amplitude, and is required in vivo for full actomyosin force generation during merozoite invasion of red blood cells."},"narrative":{"mechanistic_narrative":"ELC (PF3D7_1017500) is an essential myosin light chain of the Plasmodium glideosome, the actomyosin motor that powers parasite gliding motility and merozoite invasion of red blood cells [PMID:28893907, PMID:33104759]. It functions as a second light chain of the class-XIV myosin PfMyoA, binding a degenerate IQ motif on the MyoA neck/lever-arm region adjacent to the MTIP-binding site and co-localizing with MTIP to the glideosome [PMID:28893907, PMID:33051581]. Unlike MTIP, ELC cannot associate with the MyoA heavy chain on its own; its binding is strictly dependent on prior MTIP engagement, and the two light chains together drive maximal actin gliding speed, consistent with ELC stiffening the MyoA lever arm — by inducing secondary structure in MyoA and thereby amplifying motor-domain motions — to tune the motor's mechano-chemical output [PMID:28978649, PMID:33051581, PMID:33046215]. This structural role is calcium-independent, as ELC structure is unaffected by calcium binding [PMID:33051581]. Conditional genetic disruption of ELC in P. falciparum merozoites produces an incomplete-invasion phenotype that defines a specific mid-invasion energetic barrier, establishing that ELC-dependent motor force is required in vivo for successful RBC entry and for malaria pathogenesis [PMID:33046215, PMID:33104759].","teleology":[{"year":2017,"claim":"Establishing that the glideosome myosin carries a second, previously unrecognized light chain answered whether MTIP alone constitutes the MyoA regulatory apparatus, revealing ELC as a distinct component that enhances motor output.","evidence":"Co-immunoprecipitation from P. berghei/P. falciparum lysates, live imaging, and in vitro actin gliding assays with recombinant proteins","pmids":["28893907","28978649"],"confidence":"High","gaps":["The structural basis of ELC binding to the MyoA neck was not resolved at this stage","Whether ELC is essential in vivo was not tested"],"attribution":[{"species":"Plasmodium berghei","strain":""},{"species":"Plasmodium falciparum","strain":""}]},{"year":2017,"claim":"Reconstitution with purified recombinant proteins established the hierarchy of light-chain assembly, showing ELC cannot bind the MyoA heavy chain independently and requires MTIP to be bound first, defining ELC as a lever-arm component that amplifies motor-domain motion.","evidence":"Baculovirus/Sf9 recombinant expression, co-purification, deletion-mutant analysis, and in vitro actin gliding assays","pmids":["28978649"],"confidence":"High","gaps":["Atomic mode of MyoA recognition by ELC not yet determined","Physiological consequence of losing ELC in the parasite untested"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2020,"claim":"Crystallographic and biophysical analysis answered how ELC engages MyoA and whether calcium regulates it, revealing binding to a conserved IQ motif, a conformational change between free and bound states, and calcium-independence — reframing ELC as a structural stiffener rather than a calcium sensor.","evidence":"X-ray crystallography of the trimeric PfMyoA sub-complex, SAXS, and comparative structural analysis with Toxoplasma ELC","pmids":["33051581"],"confidence":"High","gaps":["Single lab; full-length actomyosin context not visualized here","Quantitative link between lever-arm stiffening and force output not directly measured"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2020,"claim":"Full-length motor structures combined with kinetics and conditional genetics answered both how the degenerate IQ motif recognizes ELC and whether ELC matters in the living parasite, demonstrating ELC tunes the motor's mechano-chemistry and is essential for invasion.","evidence":"Full-length PfMyoA crystal structures in two motor-cycle states, molecular dynamics, kinetic ATPase and gliding assays with variants, and conditional mutagenesis in P. falciparum","pmids":["33046215"],"confidence":"High","gaps":["Precise quantitative contribution of ELC to in vivo force not isolated from other motor components","How ELC loss propagates to whole-glideosome function not fully dissected"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2020,"claim":"Conditional disruption with live imaging pinpointed the specific invasion stage that requires ELC, defining ELC-dependent motor force as one of three energetic barriers to RBC entry (mid-invasion initiation).","evidence":"DiCre-based conditional knockout, live video microscopy of invasion, and quantitative invasion assays","pmids":["33104759"],"confidence":"High","gaps":["Molecular mechanism linking ELC loss to the mid-invasion arrest not resolved","Whether residual invasion reflects partial motor function or a redundant pathway unclear"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2022,"claim":"Cryo-EM of the reconstituted actomyosin complex placed ELC within the assembled motor bound to the MyoA light-chain-binding region alongside MTIP, providing structural context for the two-light-chain arrangement on filamentous actin.","evidence":"Cryo-EM structure determination of the reconstituted P. falciparum actomyosin complex","pmids":["35377914"],"confidence":"Medium","gaps":["ELC region resolved only at lower resolution, limiting atomic interpretation","Single study; dynamic behavior of ELC across the power stroke not captured"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":null,"claim":"How ELC-dependent lever-arm stiffening is quantitatively converted into the force needed at the mid-invasion barrier, and whether ELC has any glideosome function beyond MyoA light-chain support, remain unresolved.","evidence":"","pmids":[],"confidence":"High","gaps":["No direct force measurement isolating the ELC contribution in intact merozoites","No evidence for ELC roles outside the PfMyoA complex in the available corpus","Regulation of ELC assembly onto MyoA in vivo not characterized"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]}],"mechanism_profile":{"molecular_activity":[],"localization":[],"pathway":[],"complexes":["Glideosome (PfMyoA motor complex with MTIP and ELC)","PfMyoA trimeric light-chain sub-complex (PfMyoA:MTIP:ELC)","PfAct1:PfMyoA actomyosin complex"],"partners":["PFMYOA / MYOA HEAVY CHAIN (BINDS DEGENERATE IQ MOTIF ON LEVER ARM)","MTIP (REQUIRED FOR ELC BINDING TO MYOA HEAVY CHAIN)","PFACT1 (AS PART OF THE ACTOMYOSIN COMPLEX)"],"other_free_text":["ELC binding to the MyoA heavy chain is dependent on prior MTIP binding; ELC cannot bind the heavy chain independently [#1]","ELC and MTIP together confer maximal actin gliding speed relative to MTIP alone [#0, #1]","ELC adopts distinct free versus MyoA-bound conformations and is proposed to stiffen the MyoA lever arm by inducing secondary structure in MyoA [#2]","ELC structure is calcium-independent [#2]","Conditional disruption in P. falciparum merozoites causes an incomplete-invasion phenotype defining a mid-invasion energetic barrier and is essential for pathogenesis [#3, #4]"]}},"prefetch_data":{},"corpus_meta":[{"pmid":"28893907","id":"PMC_28893907","title":"Compositional and expression analyses of the glideosome during the Plasmodium life cycle reveal an additional myosin light chain required for maximum motility.","date":"2017","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/28893907","citation_count":33,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["ELC"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"28978649","id":"PMC_28978649","title":"Reconstitution of the core of the malaria parasite glideosome with recombinant Plasmodium class XIV myosin A and Plasmodium actin.","date":"2017","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/28978649","citation_count":26,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["PfELC"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"33046215","id":"PMC_33046215","title":"Full-length Plasmodium falciparum myosin A and essential light chain PfELC structures provide new anti-malarial targets.","date":"2020","source":"eLife","url":"https://pubmed.ncbi.nlm.nih.gov/33046215","citation_count":24,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["PfELC"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"33104759","id":"PMC_33104759","title":"Actomyosin forces and the energetics of red blood cell invasion by the malaria parasite Plasmodium falciparum.","date":"2020","source":"PLoS pathogens","url":"https://pubmed.ncbi.nlm.nih.gov/33104759","citation_count":24,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["curated_ref"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"33051581","id":"PMC_33051581","title":"Structural role of essential light chains in the apicomplexan glideosome.","date":"2020","source":"Communications biology","url":"https://pubmed.ncbi.nlm.nih.gov/33051581","citation_count":17,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["ELC"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"35377914","id":"PMC_35377914","title":"High-resolution structures of malaria parasite actomyosin and actin filaments.","date":"2022","source":"PLoS pathogens","url":"https://pubmed.ncbi.nlm.nih.gov/35377914","citation_count":17,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["PfELC"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"37308472","id":"PMC_37308472","title":"Mechanism of small molecule inhibition of Plasmodium falciparum myosin A informs antimalarial drug design.","date":"2023","source":"Nature communications","url":"https://pubmed.ncbi.nlm.nih.gov/37308472","citation_count":16,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["curated_ref"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":6042,"output_tokens":1902,"usd":0.023328,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":6990,"output_tokens":3253,"usd":0.058138,"stage2_stop_reason":"end_turn"},"total_usd":0.081466,"stage1_batch_id":"msgbatch_01DisAaTypwmC8QwdMBuePHo","stage2_batch_id":"msgbatch_0184zxZTqxiEfdYYfPMfkqjb","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2017,\n      \"finding\": \"ELC (PF3D7_1017500) was identified as an additional myosin light chain component of the P. berghei glideosome complex; it binds the MyoA neck region adjacent to the MTIP-binding site, and co-localizes with MTIP to the glideosome. Co-expression of MyoA with both light chains (ELC and MTIP) enhances MyoA-dependent actin motility compared to MyoA with MTIP alone.\",\n      \"method\": \"Co-immunoprecipitation/co-purification from parasite lysates, live imaging of P. berghei stages, in vitro actin gliding assay with recombinant proteins\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 / Strong — binding site mapping, localization, and functional motility assay all reported; independently corroborated in the companion paper (PMID:28978649)\",\n      \"pmids\": [\"28893907\"],\n      \"is_preprint\": false,\n      \"attribution\": [\n        {\"species\": \"Plasmodium berghei\", \"strain\": \"\"},\n        {\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}\n      ]\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"PfELC (PF3D7_1017500) co-purified with PfMyoA isolated from P. falciparum parasite lysates, confirming it is a bona fide light chain of PfMyoA. Crucially, PfELC binding to the PfMyoA heavy chain required that MTIP also be bound; unlike MTIP, PfELC cannot bind the heavy chain independently. Actin gliding speed was fastest when both PfELC and MTIP were present, consistent with the light-chain-binding domain acting as a lever arm to amplify motor domain motions.\",\n      \"method\": \"Baculovirus/Sf9 recombinant expression, co-purification, in vitro actin gliding assay, deletion mutant analysis\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — reconstitution in vitro with purified recombinant proteins, mutagenesis/deletion analysis, functional motility assay; replicated across two concurrent studies\",\n      \"pmids\": [\"28978649\"],\n      \"is_preprint\": false,\n      \"attribution\": [\n        {\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}\n      ]\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"Crystal structure of PfELC (PF3D7_1017500) as part of a trimeric sub-complex with PfMyoA reveals that PfELC adopts a distinct structure in its free versus MyoA-bound state, and that it binds a conserved IQ motif on MyoA. Structural and biophysical analysis demonstrated that calcium binding has no influence on the structure of PfELC. The ELC is proposed to stiffen the MyoA lever arm by inducing secondary structure in MyoA.\",\n      \"method\": \"X-ray crystallography of trimeric sub-complex, biophysical analysis (SAXS), comparative structural analysis with Toxoplasma ELC\",\n      \"journal\": \"Communications biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — crystal structure with functional inference; calcium-independence validated biophysically; single lab but multiple orthogonal structural methods\",\n      \"pmids\": [\"33051581\"],\n      \"is_preprint\": false,\n      \"attribution\": [\n        {\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}\n      ]\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"Full-length cryo-EM/crystal structures of PfMyoA in two motor-cycle states revealed the mode of recognition of PfELC (PF3D7_1017500) by a degenerate IQ motif on the PfMyoA lever arm. Kinetic and motility assays with PfMyoA variants demonstrated that PfELC contributes to tuning the motor's mechano-chemical properties. Conditional genetic disruption of PfELC in P. falciparum merozoites provided evidence for an essential role of PfELC in malaria pathogenesis.\",\n      \"method\": \"X-ray crystallography (full-length PfMyoA structures in two states), molecular dynamics, kinetic ATPase assays, actin gliding assay with PfMyoA variants, conditional genetic mutagenesis in P. falciparum\",\n      \"journal\": \"eLife\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — crystal structure plus kinetic assays plus in-parasite conditional mutagenesis; multiple orthogonal methods in single rigorous study\",\n      \"pmids\": [\"33046215\"],\n      \"is_preprint\": false,\n      \"attribution\": [\n        {\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}\n      ]\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"Conditional genetic disruption of PfELC (PF3D7_1017500) in P. falciparum merozoites produced a distinct incomplete-invasion phenotype, defining one of three energetic barriers to successful RBC entry (mid-invasion initiation). This established that ELC-dependent motor force is required at a specific stage of merozoite invasion.\",\n      \"method\": \"Conditional mutagenesis (DiCre-based), live video microscopy of invasion, quantitative invasion assay\",\n      \"journal\": \"PLoS pathogens\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — conditional KO with live imaging and quantitative phenotypic readout; single lab but rigorous genetic approach with multiple control mutants\",\n      \"pmids\": [\"33104759\"],\n      \"is_preprint\": false,\n      \"attribution\": [\n        {\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}\n      ]\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"High-resolution cryo-EM structure of the P. falciparum actomyosin complex visualized PfELC (PF3D7_1017500) bound to the PfMyoA light-chain-binding region alongside PfMTIP, providing atomic-level detail of the PfAct1:PfMyoA interface and lower-resolution visualization of the two-light-chain arrangement.\",\n      \"method\": \"Cryo-EM structure determination of reconstituted actomyosin complex\",\n      \"journal\": \"PLoS pathogens\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1 / Weak — high-resolution structure but PfELC region resolved only at lower resolution; single study\",\n      \"pmids\": [\"35377914\"],\n      \"is_preprint\": false,\n      \"attribution\": [\n        {\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}\n      ]\n    }\n  ],\n  \"current_model\": \"PfELC (PF3D7_1017500) is an essential myosin light chain of the Plasmodium glideosome that binds a degenerate IQ motif on the PfMyoA lever arm in a MTIP-dependent manner, stiffens the lever arm to enhance motor stroke amplitude, and is required in vivo for full actomyosin force generation during merozoite invasion of red blood cells.\"\n}\n```","stage2_raw":"```json\n{\n  \"mechanistic_narrative\": \"ELC (PF3D7_1017500) is an essential myosin light chain of the Plasmodium glideosome, the actomyosin motor that powers parasite gliding motility and merozoite invasion of red blood cells [#0, #4]. It functions as a second light chain of the class-XIV myosin PfMyoA, binding a degenerate IQ motif on the MyoA neck/lever-arm region adjacent to the MTIP-binding site and co-localizing with MTIP to the glideosome [#0, #2]. Unlike MTIP, ELC cannot associate with the MyoA heavy chain on its own; its binding is strictly dependent on prior MTIP engagement, and the two light chains together drive maximal actin gliding speed, consistent with ELC stiffening the MyoA lever arm — by inducing secondary structure in MyoA and thereby amplifying motor-domain motions — to tune the motor's mechano-chemical output [#1, #2, #3]. This structural role is calcium-independent, as ELC structure is unaffected by calcium binding [#2]. Conditional genetic disruption of ELC in P. falciparum merozoites produces an incomplete-invasion phenotype that defines a specific mid-invasion energetic barrier, establishing that ELC-dependent motor force is required in vivo for successful RBC entry and for malaria pathogenesis [#3, #4].\",\n  \"teleology\": [\n    {\n      \"year\": 2017,\n      \"claim\": \"Establishing that the glideosome myosin carries a second, previously unrecognized light chain answered whether MTIP alone constitutes the MyoA regulatory apparatus, revealing ELC as a distinct component that enhances motor output.\",\n      \"evidence\": \"Co-immunoprecipitation from P. berghei/P. falciparum lysates, live imaging, and in vitro actin gliding assays with recombinant proteins\",\n      \"pmids\": [\"28893907\", \"28978649\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"The structural basis of ELC binding to the MyoA neck was not resolved at this stage\",\n        \"Whether ELC is essential in vivo was not tested\"\n      ],\n      \"attribution\": [\n        {\"species\": \"Plasmodium berghei\", \"strain\": \"\"},\n        {\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}\n      ]\n    },\n    {\n      \"year\": 2017,\n      \"claim\": \"Reconstitution with purified recombinant proteins established the hierarchy of light-chain assembly, showing ELC cannot bind the MyoA heavy chain independently and requires MTIP to be bound first, defining ELC as a lever-arm component that amplifies motor-domain motion.\",\n      \"evidence\": \"Baculovirus/Sf9 recombinant expression, co-purification, deletion-mutant analysis, and in vitro actin gliding assays\",\n      \"pmids\": [\"28978649\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Atomic mode of MyoA recognition by ELC not yet determined\",\n        \"Physiological consequence of losing ELC in the parasite untested\"\n      ],\n      \"attribution\": [\n        {\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}\n      ]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"Crystallographic and biophysical analysis answered how ELC engages MyoA and whether calcium regulates it, revealing binding to a conserved IQ motif, a conformational change between free and bound states, and calcium-independence — reframing ELC as a structural stiffener rather than a calcium sensor.\",\n      \"evidence\": \"X-ray crystallography of the trimeric PfMyoA sub-complex, SAXS, and comparative structural analysis with Toxoplasma ELC\",\n      \"pmids\": [\"33051581\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Single lab; full-length actomyosin context not visualized here\",\n        \"Quantitative link between lever-arm stiffening and force output not directly measured\"\n      ],\n      \"attribution\": [\n        {\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}\n      ]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"Full-length motor structures combined with kinetics and conditional genetics answered both how the degenerate IQ motif recognizes ELC and whether ELC matters in the living parasite, demonstrating ELC tunes the motor's mechano-chemistry and is essential for invasion.\",\n      \"evidence\": \"Full-length PfMyoA crystal structures in two motor-cycle states, molecular dynamics, kinetic ATPase and gliding assays with variants, and conditional mutagenesis in P. falciparum\",\n      \"pmids\": [\"33046215\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Precise quantitative contribution of ELC to in vivo force not isolated from other motor components\",\n        \"How ELC loss propagates to whole-glideosome function not fully dissected\"\n      ],\n      \"attribution\": [\n        {\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}\n      ]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"Conditional disruption with live imaging pinpointed the specific invasion stage that requires ELC, defining ELC-dependent motor force as one of three energetic barriers to RBC entry (mid-invasion initiation).\",\n      \"evidence\": \"DiCre-based conditional knockout, live video microscopy of invasion, and quantitative invasion assays\",\n      \"pmids\": [\"33104759\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Molecular mechanism linking ELC loss to the mid-invasion arrest not resolved\",\n        \"Whether residual invasion reflects partial motor function or a redundant pathway unclear\"\n      ],\n      \"attribution\": [\n        {\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}\n      ]\n    },\n    {\n      \"year\": 2022,\n      \"claim\": \"Cryo-EM of the reconstituted actomyosin complex placed ELC within the assembled motor bound to the MyoA light-chain-binding region alongside MTIP, providing structural context for the two-light-chain arrangement on filamentous actin.\",\n      \"evidence\": \"Cryo-EM structure determination of the reconstituted P. falciparum actomyosin complex\",\n      \"pmids\": [\"35377914\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"ELC region resolved only at lower resolution, limiting atomic interpretation\",\n        \"Single study; dynamic behavior of ELC across the power stroke not captured\"\n      ],\n      \"attribution\": [\n        {\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}\n      ]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How ELC-dependent lever-arm stiffening is quantitatively converted into the force needed at the mid-invasion barrier, and whether ELC has any glideosome function beyond MyoA light-chain support, remain unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"No direct force measurement isolating the ELC contribution in intact merozoites\",\n        \"No evidence for ELC roles outside the PfMyoA complex in the available corpus\",\n        \"Regulation of ELC assembly onto MyoA in vivo not characterized\"\n      ],\n      \"attribution\": [\n        {\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}\n      ]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0017022\", \"supporting_discovery_ids\": [0, 1, 2, 3, 5]},\n      {\"term_id\": \"GO:0032036\", \"supporting_discovery_ids\": [1, 2, 3]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0031430\", \"supporting_discovery_ids\": [0]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"GO:0030050\", \"supporting_discovery_ids\": [0, 1]},\n      {\"term_id\": \"GO:0044409\", \"supporting_discovery_ids\": [3, 4]}\n    ],\n    \"complexes\": [\n      \"Glideosome (PfMyoA motor complex with MTIP and ELC)\",\n      \"PfMyoA trimeric light-chain sub-complex (PfMyoA:MTIP:ELC)\",\n      \"PfAct1:PfMyoA actomyosin complex\"\n    ],\n    \"partners\": [\n      \"PfMyoA / MyoA heavy chain (binds degenerate IQ motif on lever arm)\",\n      \"MTIP (required for ELC binding to MyoA heavy chain)\",\n      \"PfAct1 (as part of the actomyosin complex)\"\n    ],\n    \"other_free_text\": [\n      \"ELC binding to the MyoA heavy chain is dependent on prior MTIP binding; ELC cannot bind the heavy chain independently [#1]\",\n      \"ELC and MTIP together confer maximal actin gliding speed relative to MTIP alone [#0, #1]\",\n      \"ELC adopts distinct free versus MyoA-bound conformations and is proposed to stiffen the MyoA lever arm by inducing secondary structure in MyoA [#2]\",\n      \"ELC structure is calcium-independent [#2]\",\n      \"Conditional disruption in P. falciparum merozoites causes an incomplete-invasion phenotype defining a mid-invasion energetic barrier and is essential for pathogenesis [#3, #4]\"\n    ]\n  }\n}\n```","audit_flag":null,"strains":[{"strain":"Pf3D7","gene_id":"PF3D7_1017500","name":null,"product":"myosin essential light chain ELC","uniprot_acc":null,"chromosome":null,"start_pos":null},{"strain":"PbANKA","gene_id":"PBANKA_0501800","name":null,"product":"myosin essential light chain ELC, putative","uniprot_acc":null,"chromosome":null,"start_pos":null}],"gene_symbol":"ELC","evaluation":null}