{"gene":"TG_218520","gene_symbol":"MIC6","run_date":"2026-09-08T11:06:34","timeline":{"discoveries":[{"year":2001,"finding":"MIC6 is a transmembrane micronemal protein that functions as an escorter for two soluble adhesins MIC1 and MIC4, targeting them to the micronemes. The sorting signal(s) reside in MIC6's cytoplasmic tail, while its association with MIC1 involves a lumenal EGF-like domain. MIC4 binds directly to MIC1 and behaves as a passive cargo molecule. MIC1 is absolutely required for the complex to exit early secretory compartments (quality control).","method":"Gene disruption (knockout) of MIC1, MIC4, and MIC6; domain mapping; immunofluorescence; secretory pathway analysis","journal":"The Journal of cell biology","confidence":"High","confidence_rationale":"Tier 2 / Strong — reciprocal genetic dissection with multiple knockouts, domain mapping, and functional trafficking assays; replicated and foundational study","pmids":["11157983"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2002,"finding":"MIC6 exhibits classical type I membrane topology during transport along the secretory pathway and in micronemes. MIC6 is proteolytically processed at its N-terminus, probably in the trans-Golgi network (cleavage site mapped). Additionally, MIC6 is proteolytically cleaved near its C-terminal transmembrane domain (intramembrane cleavage) upon microneme discharge at the parasite surface.","method":"Site-specific mutagenesis to map cleavage sites; pulse-chase and subcellular fractionation; fusion protein assays","journal":"Journal of cell science","confidence":"High","confidence_rationale":"Tier 1–2 / Strong — mutagenesis mapping of cleavage sites, topological analysis, replicated across multiple family members in same study","pmids":["11861763"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2002,"finding":"The intramembrane cleavage of MIC6 by micronemal protein protease MPP1 occurs within the membrane-spanning domain at a conserved site (IA↓GG motif conserved across apicomplexan microneme proteins). Fusion of surface antigen SAG1 with MIC6/MIC2 transmembrane domains showed the ectodomain is not required for cleavage site recognition, and MPP1 is constitutively active at the parasite surface.","method":"Site-directed mutagenesis of transmembrane domain; chimeric SAG1-TM fusion proteins; cleavage assays on parasite surface","journal":"The EMBO journal","confidence":"High","confidence_rationale":"Tier 1 / Strong — reconstitution with chimeric proteins, site-directed mutagenesis, multiple orthogonal constructs tested","pmids":["11927542"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2005,"finding":"Rhomboid proteases TgROM1, TgROM2, and TgROM5 are active serine proteases (cleave Drosophila Spitz substrate). TgROM2 cleaves chimeric proteins containing the transmembrane domains of TgMIC2 and TgMIC12, identifying rhomboids as candidate MPP1 enzymes responsible for intramembrane cleavage of microneme proteins including MIC6.","method":"Heterologous rhomboid cleavage assays with chimeric TM-domain substrates; characterization of six T. gondii rhomboid-like proteins","journal":"International journal for parasitology","confidence":"Medium","confidence_rationale":"Tier 1–2 / Weak — direct in vitro cleavage assay with chimeric MIC TM domains, but MIC6 TM domain specifically not tested (MIC2/MIC12 tested); single lab","pmids":["15913633"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2005,"finding":"The C-terminal galectin-like domain of MIC1 interacts with and stabilizes MIC6, providing the basis for a quality control mechanism for exit from early secretory compartments and trafficking of the MIC1-MIC4-MIC6 complex to micronemes. The N-terminal TSR1-like domains of MIC1 independently promote association with MIC4.","method":"Three-dimensional structure of MIC1 C-terminal domain (solved); binding assays; immunofluorescence; invasion assays with domain mutants","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 1 / Strong — crystal structure combined with functional binding assays and invasion assays; multiple orthogonal methods in one rigorous study","pmids":["16166092"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2008,"finding":"High-resolution NMR solution structure of the MIC6–MIC1 complex was determined, revealing two analogous interaction sites within separate EGF-like domains of MIC6 (EGF2 and EGF3). Both interactions are functional for host cell receptor recognition, confirmed by immunofluorescence and invasion assays. This defines a new mode of EGF domain recognition.","method":"NMR solution structure; immunofluorescence assays; host cell invasion assays","journal":"EMBO reports","confidence":"High","confidence_rationale":"Tier 1 / Strong — NMR structure plus functional validation by invasion assays; multiple orthogonal methods","pmids":["18818666"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2009,"finding":"The carboxy-terminal cytoplasmic domain (C domain) of MIC6 interacts with aldolase and the parasite cytoskeleton, revealing a link between the MIC1-MIC4-MIC6 adhesive complex and the actomyosin invasion machinery.","method":"GST pulldown of MIC6 cytoplasmic tail with T. gondii tachyzoite lysate; co-precipitation with aldolase","journal":"Parasitology research","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — pulldown assay confirmed interaction; replicated with both parasite lysate and recombinant aldolase; single lab","pmids":["19308454"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2010,"finding":"MIC6 binding to aldolase is dispensable for invasion (in contrast to AMA1 where aldolase-binding residues are essential). MIC6 is a substrate for rhomboid protease cleavage and lacks targeting information within its C-terminal domain for some trafficking steps, suggesting ectodomain-mediated interactions with unidentified proteins contribute to targeting.","method":"Mutagenesis of aldolase-binding residues; invasion assays; rhomboid cleavage susceptibility assays","journal":"Molecular microbiology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — functional mutagenesis of aldolase-binding site with invasion phenotype readout; single lab, two methods","pmids":["20545864"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2014,"finding":"Tryptophan W348 in the C-terminal cytoplasmic domain of MIC6 is the critical interaction site for aldolase binding. Mutation of W348 to valine (W348V) abolishes co-precipitation of aldolase from both T. gondii tachyzoite lysate and recombinant aldolase-His6.","method":"Site-directed mutagenesis (W348V); GST pulldown with parasite lysate and recombinant aldolase; SDS-PAGE and Western blotting","journal":"Zhongguo ji sheng chong xue yu ji sheng chong bing za zhi","confidence":"Medium","confidence_rationale":"Tier 1 / Weak — site-directed mutagenesis with in vitro binding assay; single lab, single method set","pmids":["25223060"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2015,"finding":"ROM4 (rhomboid protease 4) is responsible for shedding of MIC2 and MIC6; in rom4-ko parasites, intramembrane cleavage of MIC2 and MIC6 is abolished. ROM4-ko parasites predominantly engage in twirling motility and exhibit enhanced attachment but impaired invasion.","method":"Cre-recombinase-mediated gene knockout of ROM4; CRISPR-Cas9 knockout of ROM5; motility and invasion assays; substrate cleavage assays","journal":"Molecular microbiology","confidence":"High","confidence_rationale":"Tier 2 / Strong — genetic knockout with direct substrate cleavage assays and functional invasion/motility phenotypes; two proteases studied with complementary tools","pmids":["25846828"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2013,"finding":"MIC6 (together with MIC3), as an EGF domain-containing micronemal protein (EGF-MIC), promotes EGFR activation in host cells. Parasites deficient in MIC6 secretion (MIC1 ko) caused impaired EGFR-Akt activation, and recombinant MIC6 directly caused EGFR-Akt activation. This EGFR activation inhibits autophagic targeting of the parasitophorous vacuole, thereby preventing parasite killing.","method":"MIC1 ko and MIC3 ko parasites (deficient in EGF-MIC secretion); recombinant MIC6 stimulation of host cells; EGFR/Akt signaling readouts; LC3 accumulation assays; parasite killing assays","journal":"PLoS pathogens","confidence":"High","confidence_rationale":"Tier 2 / Strong — genetic knockouts combined with recombinant protein rescue and multiple signaling/functional readouts; single lab with orthogonal methods","pmids":["24367261"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2024,"finding":"TgMIC6 knockout in the Chinese 1 WH3 strain reduces virulence in vivo and in vitro. MIC6 enhances virulence by inhibiting host cell autophagy via activation of the EGFR-Akt-mTOR signaling pathway. Additionally, CD40L-mediated immunity partially restores control of WH3-Δmic6, indicating MIC6 also contributes to immune evasion of CD40L-dependent autophagy.","method":"CRISPR/Cas9-mediated MIC6 knockout in WH3 strain; mouse infection experiments; cytokine measurements; parasite proliferation assays; CD40L depletion with monoclonal antibody","journal":"International immunopharmacology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — CRISPR knockout with in vivo and in vitro functional phenotypes; single lab, multiple readouts but no direct biochemical mechanism confirmation","pmids":["39116491"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":"WH3"}]},{"year":2008,"finding":"NMR resonance assignments were completed for the galectin-like domain of MIC1 in complex with both the second and third EGF domains of MIC6, confirming two distinct EGF domain interaction sites on MIC6 for MIC1 binding.","method":"NMR spectroscopy (resonance assignment)","journal":"Biomolecular NMR assignments","confidence":"Medium","confidence_rationale":"Tier 1 / Weak — NMR structural assignment providing atomic-level evidence for two MIC6-EGF/MIC1 interaction sites; single lab, no functional follow-up in this paper","pmids":["19636898","19636901"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":""}]}],"current_model":"TgMIC6 is a type I transmembrane EGF domain-containing micronemal protein that acts as an escorter for soluble adhesins MIC1 and MIC4 to the micronemes (via a cytoplasmic tail sorting signal and EGF2/EGF3-mediated interaction with MIC1's galectin-like domain); upon secretion the complex bridges host cell receptors to the parasite, while the MIC6 cytoplasmic tail connects to the actomyosin motor via aldolase at W348; MIC6 is shed from the parasite surface by intramembrane cleavage within its transmembrane domain by ROM4; and MIC6's EGF domains activate host cell EGFR-Akt-mTOR signaling to suppress autophagy-mediated parasite killing."},"narrative":{"mechanistic_narrative":"TgMIC6 is a type I transmembrane micronemal protein of Toxoplasma gondii that organizes and traffics a heterotrimeric adhesive complex used for host cell invasion [PMID:11157983]. Through its lumenal EGF-like domains it recruits the soluble adhesin MIC1, which in turn binds MIC4 as passive cargo, and MIC6's cytoplasmic tail supplies the sorting signal that targets the assembled MIC1-MIC4-MIC6 complex to the micronemes [PMID:11157983]. Structural work resolved this recruitment at atomic resolution: two analogous sites within the EGF2 and EGF3 domains of MIC6 each engage the C-terminal galectin-like domain of MIC1, and this MIC1 interaction stabilizes MIC6 and provides quality control for exit from early secretory compartments [PMID:16166092, PMID:18818666]. During transport MIC6 is proteolytically matured at its N-terminus, and upon microneme discharge at the parasite surface it is shed by regulated intramembrane cleavage within its transmembrane domain at a conserved apicomplexan motif by the rhomboid protease ROM4 [PMID:11861763, PMID:11927542, PMID:25846828]. The MIC6 cytoplasmic tail links the adhesive complex to the actomyosin invasion motor by binding aldolase and the parasite cytoskeleton via a critical tryptophan residue W348, although this aldolase interaction is dispensable for invasion [PMID:19308454, PMID:20545864, PMID:25223060]. Beyond its role in invasion, MIC6 is a secreted virulence effector: its EGF domains activate host EGFR-Akt-mTOR signaling to suppress autophagy-mediated killing of the parasite, and knockout reduces virulence in vivo [PMID:24367261, PMID:39116491].","teleology":[{"year":2001,"claim":"Established that MIC6 is not merely a surface adhesin but the transmembrane escorter that traffics the soluble adhesins MIC1 and MIC4 to the micronemes, defining the architecture of an adhesive complex.","evidence":"Reciprocal gene disruption of MIC1/MIC4/MIC6, domain mapping and secretory pathway analysis in T. gondii","pmids":["11157983"],"confidence":"High","gaps":["Molecular identity of the EGF domain(s) mediating MIC1 binding not yet resolved","Cytoplasmic tail sorting signal not mapped to specific residues"],"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2002,"claim":"Defined MIC6 as a type I membrane protein subject to two distinct proteolytic events — N-terminal maturation and surface intramembrane cleavage — separating trafficking maturation from adhesin shedding.","evidence":"Site-specific mutagenesis of cleavage sites, pulse-chase, fractionation and fusion protein assays in T. gondii","pmids":["11861763"],"confidence":"High","gaps":["Protease responsible for intramembrane cleavage not identified","Functional consequence of shedding for invasion not tested"],"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2002,"claim":"Localized the intramembrane cleavage to a conserved IA↓GG motif within the transmembrane domain and showed the cleavage machinery (MPP1) is constitutively active at the surface and recognizes the TM domain independent of the ectodomain.","evidence":"Site-directed TM-domain mutagenesis and chimeric SAG1-TM fusion cleavage assays in T. gondii","pmids":["11927542"],"confidence":"High","gaps":["MPP1 enzyme not yet identified as a specific protease","Regulation of cleavage timing during discharge unresolved"],"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2005,"claim":"Identified rhomboid proteases as candidate MPP1 enzymes for microneme TM-domain cleavage, narrowing the search for the physiological MIC6 sheddase.","evidence":"Heterologous rhomboid cleavage assays with chimeric MIC TM-domain substrates in T. gondii","pmids":["15913633"],"confidence":"Medium","gaps":["MIC6 transmembrane domain specifically not tested (only MIC2/MIC12)","In vivo protease responsible for MIC6 shedding not established"],"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2005,"claim":"Provided the structural and functional basis for complex quality control by showing the MIC1 galectin-like domain binds and stabilizes MIC6, coupling assembly to secretory exit.","evidence":"Crystal structure of MIC1 C-terminal domain with binding, immunofluorescence and invasion assays in T. gondii","pmids":["16166092"],"confidence":"High","gaps":["MIC6 residues contacting MIC1 not yet defined","Stoichiometry of the assembled complex not addressed"],"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2008,"claim":"Resolved the MIC6-MIC1 interface at atomic resolution, revealing two analogous MIC1-binding sites in the EGF2 and EGF3 domains of MIC6 and defining a new mode of EGF domain recognition.","evidence":"NMR solution structure of the MIC6-MIC1 complex with resonance assignments, plus immunofluorescence and invasion assays in T. gondii","pmids":["18818666","19636898","19636901"],"confidence":"High","gaps":["Whether both EGF sites act cooperatively in vivo not resolved","Contribution of each site to receptor recognition versus complex stability not disentangled"],"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2009,"claim":"Connected the adhesive complex to the invasion motor by showing the MIC6 cytoplasmic tail binds aldolase and the parasite cytoskeleton.","evidence":"GST pulldown of the MIC6 cytoplasmic tail with tachyzoite lysate and recombinant aldolase in T. gondii","pmids":["19308454"],"confidence":"Medium","gaps":["Single-lab pulldown without genetic confirmation of functional relevance","Aldolase-binding residues not yet mapped"],"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2010,"claim":"Tested the functional necessity of the aldolase link and found it dispensable for invasion, distinguishing MIC6 from AMA1 and pointing to ectodomain-mediated interactions for some trafficking steps.","evidence":"Mutagenesis of aldolase-binding residues with invasion and rhomboid cleavage assays in T. gondii","pmids":["20545864"],"confidence":"Medium","gaps":["Identity of the ectodomain-interacting trafficking partners unknown","Redundant motor-linkage mechanisms not identified"],"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2014,"claim":"Pinpointed the aldolase-binding determinant to tryptophan W348 in the MIC6 cytoplasmic tail.","evidence":"Site-directed W348V mutagenesis with GST pulldown against parasite lysate and recombinant aldolase in T. gondii","pmids":["25223060"],"confidence":"Medium","gaps":["In vitro binding assay only; in vivo consequence of W348V not established","Single method set from a single lab"],"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2015,"claim":"Identified ROM4 as the physiological rhomboid protease that sheds MIC6 (and MIC2), linking surface intramembrane cleavage to the switch from attachment to productive invasion.","evidence":"Cre-mediated ROM4 knockout and CRISPR ROM5 knockout with substrate cleavage, motility and invasion assays in T. gondii","pmids":["25846828"],"confidence":"High","gaps":["Whether ROM4 is the sole MIC6 sheddase not fully excluded","Structural basis of ROM4 substrate selection for MIC6 not addressed"],"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2013,"claim":"Revealed a second, effector role for MIC6 beyond adhesion: its EGF domains directly activate host EGFR-Akt signaling to block autophagic targeting of the vacuole and prevent parasite killing.","evidence":"MIC1/MIC3 knockouts deficient in EGF-MIC secretion, recombinant MIC6 stimulation, EGFR/Akt readouts, LC3 and parasite killing assays in T. gondii","pmids":["24367261"],"confidence":"High","gaps":["Direct MIC6-EGFR binding interface not mapped","Whether the same EGF sites used for MIC1 binding engage EGFR unresolved"],"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2024,"claim":"Established MIC6 as an in vivo virulence factor in the Chinese 1 WH3 strain, acting through EGFR-Akt-mTOR-mediated autophagy suppression and contributing to evasion of CD40L-dependent immunity.","evidence":"CRISPR/Cas9 MIC6 knockout in WH3, mouse infection, cytokine and proliferation assays, and CD40L depletion in T. gondii WH3","pmids":["39116491"],"confidence":"Medium","gaps":["No direct biochemical confirmation of the signaling mechanism in this strain","Relative contribution of adhesion versus immune-evasion roles to virulence not separated"],"attribution":[{"species":"Toxoplasma gondii","strain":"WH3"}]},{"year":null,"claim":"How MIC6's EGF domains partition between their intramolecular role in MIC1 binding/complex assembly and their extracellular role in host EGFR activation remains unresolved.","evidence":"","pmids":[],"confidence":"Low","gaps":["No structural map of a MIC6-EGFR interaction","Ectodomain trafficking partners inferred but unidentified","Whether shed versus membrane-bound MIC6 mediates EGFR signaling not determined"],"attribution":[{"species":"Toxoplasma gondii","strain":""}]}],"mechanism_profile":{"molecular_activity":[],"localization":[],"pathway":[],"complexes":["MIC1-MIC4-MIC6 adhesive complex"],"partners":["MIC1 (GALECTIN-LIKE DOMAIN BINDS MIC6 EGF2/EGF3)","MIC4 (PASSIVE CARGO, BINDS MIC1)","ALDOLASE (BINDS MIC6 CYTOPLASMIC TAIL VIA W348)","PARASITE CYTOSKELETON / ACTOMYOSIN MOTOR","ROM4 (RHOMBOID PROTEASE SHEDDASE)","HOST EGFR"],"other_free_text":["N-terminal proteolytic maturation occurs probably in the trans-Golgi network [#1]","Intramembrane cleavage occurs at a conserved IA↓GG motif within the transmembrane domain [#2]","MPP1/rhomboid activity is constitutively active at the parasite surface and recognizes the TM domain independent of the ectodomain [#2]","Aldolase binding is dispensable for invasion, unlike AMA1 [#7]","In WH3 strain, MIC6 knockout reduces virulence and CD40L-mediated immunity partially restores control [#11]"]},"strain_conflicts":[]},"prefetch_data":{},"corpus_meta":[{"pmid":"11157983","id":"PMC_11157983","title":"Identification and characterization of an escorter for two secretory adhesins in Toxoplasma gondii.","date":"2001","source":"The Journal of cell biology","url":"https://pubmed.ncbi.nlm.nih.gov/11157983","citation_count":178,"is_preprint":false},{"pmid":"11566297","id":"PMC_11566297","title":"Microneme proteins: structural and functional 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strains.","date":"2024","source":"International immunopharmacology","url":"https://pubmed.ncbi.nlm.nih.gov/39116491","citation_count":2,"is_preprint":false},{"pmid":"26174829","id":"PMC_26174829","title":"Sequence Diversity in MIC6 Gene among Toxoplasma gondii Isolates from Different Hosts and Geographical Locations.","date":"2015","source":"The Korean journal of parasitology","url":"https://pubmed.ncbi.nlm.nih.gov/26174829","citation_count":1,"is_preprint":false},{"pmid":"19636901","id":"PMC_19636901","title":"Complete NMR assignments for the second EGF domain of MIC6 from Toxoplasma gondii and re-assignment in complex with the galectin-like domain of MIC1.","date":"2008","source":"Biomolecular NMR assignments","url":"https://pubmed.ncbi.nlm.nih.gov/19636901","citation_count":1,"is_preprint":false},{"pmid":"41459975","id":"PMC_41459975","title":"A novel anti-Toxoplasma peptide suppresses parasite invasion and rescues host autophagic defenses.","date":"2025","source":"Microbiology spectrum","url":"https://pubmed.ncbi.nlm.nih.gov/41459975","citation_count":1,"is_preprint":false},{"pmid":"25223060","id":"PMC_25223060","title":"[Protein interaction site of Toxoplasma gondii microneme protein 6 and aldolase determined by site-directed mutagenesis].","date":"2014","source":"Zhongguo ji sheng chong xue yu ji sheng chong bing za zhi = Chinese journal of parasitology & parasitic diseases","url":"https://pubmed.ncbi.nlm.nih.gov/25223060","citation_count":0,"is_preprint":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":19245,"output_tokens":3727,"usd":0.05682,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":9820,"output_tokens":5144,"usd":0.08885,"stage2_stop_reason":"end_turn"},"total_usd":0.14567,"stage1_batch_id":"msgbatch_01WokvBYTB6JLnYrpD4rXnyV","stage2_batch_id":"msgbatch_01M7hsQDvz6AqVC9DLVjQzzc","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2001,\n      \"finding\": \"MIC6 is a transmembrane micronemal protein that functions as an escorter for two soluble adhesins MIC1 and MIC4, targeting them to the micronemes. The sorting signal(s) reside in MIC6's cytoplasmic tail, while its association with MIC1 involves a lumenal EGF-like domain. MIC4 binds directly to MIC1 and behaves as a passive cargo molecule. MIC1 is absolutely required for the complex to exit early secretory compartments (quality control).\",\n      \"method\": \"Gene disruption (knockout) of MIC1, MIC4, and MIC6; domain mapping; immunofluorescence; secretory pathway analysis\",\n      \"journal\": \"The Journal of cell biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — reciprocal genetic dissection with multiple knockouts, domain mapping, and functional trafficking assays; replicated and foundational study\",\n      \"pmids\": [\"11157983\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2002,\n      \"finding\": \"MIC6 exhibits classical type I membrane topology during transport along the secretory pathway and in micronemes. MIC6 is proteolytically processed at its N-terminus, probably in the trans-Golgi network (cleavage site mapped). Additionally, MIC6 is proteolytically cleaved near its C-terminal transmembrane domain (intramembrane cleavage) upon microneme discharge at the parasite surface.\",\n      \"method\": \"Site-specific mutagenesis to map cleavage sites; pulse-chase and subcellular fractionation; fusion protein assays\",\n      \"journal\": \"Journal of cell science\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 / Strong — mutagenesis mapping of cleavage sites, topological analysis, replicated across multiple family members in same study\",\n      \"pmids\": [\"11861763\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2002,\n      \"finding\": \"The intramembrane cleavage of MIC6 by micronemal protein protease MPP1 occurs within the membrane-spanning domain at a conserved site (IA↓GG motif conserved across apicomplexan microneme proteins). Fusion of surface antigen SAG1 with MIC6/MIC2 transmembrane domains showed the ectodomain is not required for cleavage site recognition, and MPP1 is constitutively active at the parasite surface.\",\n      \"method\": \"Site-directed mutagenesis of transmembrane domain; chimeric SAG1-TM fusion proteins; cleavage assays on parasite surface\",\n      \"journal\": \"The EMBO journal\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — reconstitution with chimeric proteins, site-directed mutagenesis, multiple orthogonal constructs tested\",\n      \"pmids\": [\"11927542\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2005,\n      \"finding\": \"Rhomboid proteases TgROM1, TgROM2, and TgROM5 are active serine proteases (cleave Drosophila Spitz substrate). TgROM2 cleaves chimeric proteins containing the transmembrane domains of TgMIC2 and TgMIC12, identifying rhomboids as candidate MPP1 enzymes responsible for intramembrane cleavage of microneme proteins including MIC6.\",\n      \"method\": \"Heterologous rhomboid cleavage assays with chimeric TM-domain substrates; characterization of six T. gondii rhomboid-like proteins\",\n      \"journal\": \"International journal for parasitology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1–2 / Weak — direct in vitro cleavage assay with chimeric MIC TM domains, but MIC6 TM domain specifically not tested (MIC2/MIC12 tested); single lab\",\n      \"pmids\": [\"15913633\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2005,\n      \"finding\": \"The C-terminal galectin-like domain of MIC1 interacts with and stabilizes MIC6, providing the basis for a quality control mechanism for exit from early secretory compartments and trafficking of the MIC1-MIC4-MIC6 complex to micronemes. The N-terminal TSR1-like domains of MIC1 independently promote association with MIC4.\",\n      \"method\": \"Three-dimensional structure of MIC1 C-terminal domain (solved); binding assays; immunofluorescence; invasion assays with domain mutants\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — crystal structure combined with functional binding assays and invasion assays; multiple orthogonal methods in one rigorous study\",\n      \"pmids\": [\"16166092\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2008,\n      \"finding\": \"High-resolution NMR solution structure of the MIC6–MIC1 complex was determined, revealing two analogous interaction sites within separate EGF-like domains of MIC6 (EGF2 and EGF3). Both interactions are functional for host cell receptor recognition, confirmed by immunofluorescence and invasion assays. This defines a new mode of EGF domain recognition.\",\n      \"method\": \"NMR solution structure; immunofluorescence assays; host cell invasion assays\",\n      \"journal\": \"EMBO reports\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — NMR structure plus functional validation by invasion assays; multiple orthogonal methods\",\n      \"pmids\": [\"18818666\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"The carboxy-terminal cytoplasmic domain (C domain) of MIC6 interacts with aldolase and the parasite cytoskeleton, revealing a link between the MIC1-MIC4-MIC6 adhesive complex and the actomyosin invasion machinery.\",\n      \"method\": \"GST pulldown of MIC6 cytoplasmic tail with T. gondii tachyzoite lysate; co-precipitation with aldolase\",\n      \"journal\": \"Parasitology research\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — pulldown assay confirmed interaction; replicated with both parasite lysate and recombinant aldolase; single lab\",\n      \"pmids\": [\"19308454\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"MIC6 binding to aldolase is dispensable for invasion (in contrast to AMA1 where aldolase-binding residues are essential). MIC6 is a substrate for rhomboid protease cleavage and lacks targeting information within its C-terminal domain for some trafficking steps, suggesting ectodomain-mediated interactions with unidentified proteins contribute to targeting.\",\n      \"method\": \"Mutagenesis of aldolase-binding residues; invasion assays; rhomboid cleavage susceptibility assays\",\n      \"journal\": \"Molecular microbiology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — functional mutagenesis of aldolase-binding site with invasion phenotype readout; single lab, two methods\",\n      \"pmids\": [\"20545864\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"Tryptophan W348 in the C-terminal cytoplasmic domain of MIC6 is the critical interaction site for aldolase binding. Mutation of W348 to valine (W348V) abolishes co-precipitation of aldolase from both T. gondii tachyzoite lysate and recombinant aldolase-His6.\",\n      \"method\": \"Site-directed mutagenesis (W348V); GST pulldown with parasite lysate and recombinant aldolase; SDS-PAGE and Western blotting\",\n      \"journal\": \"Zhongguo ji sheng chong xue yu ji sheng chong bing za zhi\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1 / Weak — site-directed mutagenesis with in vitro binding assay; single lab, single method set\",\n      \"pmids\": [\"25223060\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"ROM4 (rhomboid protease 4) is responsible for shedding of MIC2 and MIC6; in rom4-ko parasites, intramembrane cleavage of MIC2 and MIC6 is abolished. ROM4-ko parasites predominantly engage in twirling motility and exhibit enhanced attachment but impaired invasion.\",\n      \"method\": \"Cre-recombinase-mediated gene knockout of ROM4; CRISPR-Cas9 knockout of ROM5; motility and invasion assays; substrate cleavage assays\",\n      \"journal\": \"Molecular microbiology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — genetic knockout with direct substrate cleavage assays and functional invasion/motility phenotypes; two proteases studied with complementary tools\",\n      \"pmids\": [\"25846828\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"MIC6 (together with MIC3), as an EGF domain-containing micronemal protein (EGF-MIC), promotes EGFR activation in host cells. Parasites deficient in MIC6 secretion (MIC1 ko) caused impaired EGFR-Akt activation, and recombinant MIC6 directly caused EGFR-Akt activation. This EGFR activation inhibits autophagic targeting of the parasitophorous vacuole, thereby preventing parasite killing.\",\n      \"method\": \"MIC1 ko and MIC3 ko parasites (deficient in EGF-MIC secretion); recombinant MIC6 stimulation of host cells; EGFR/Akt signaling readouts; LC3 accumulation assays; parasite killing assays\",\n      \"journal\": \"PLoS pathogens\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — genetic knockouts combined with recombinant protein rescue and multiple signaling/functional readouts; single lab with orthogonal methods\",\n      \"pmids\": [\"24367261\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"TgMIC6 knockout in the Chinese 1 WH3 strain reduces virulence in vivo and in vitro. MIC6 enhances virulence by inhibiting host cell autophagy via activation of the EGFR-Akt-mTOR signaling pathway. Additionally, CD40L-mediated immunity partially restores control of WH3-Δmic6, indicating MIC6 also contributes to immune evasion of CD40L-dependent autophagy.\",\n      \"method\": \"CRISPR/Cas9-mediated MIC6 knockout in WH3 strain; mouse infection experiments; cytokine measurements; parasite proliferation assays; CD40L depletion with monoclonal antibody\",\n      \"journal\": \"International immunopharmacology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — CRISPR knockout with in vivo and in vitro functional phenotypes; single lab, multiple readouts but no direct biochemical mechanism confirmation\",\n      \"pmids\": [\"39116491\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"WH3\"}]\n    },\n    {\n      \"year\": 2008,\n      \"finding\": \"NMR resonance assignments were completed for the galectin-like domain of MIC1 in complex with both the second and third EGF domains of MIC6, confirming two distinct EGF domain interaction sites on MIC6 for MIC1 binding.\",\n      \"method\": \"NMR spectroscopy (resonance assignment)\",\n      \"journal\": \"Biomolecular NMR assignments\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1 / Weak — NMR structural assignment providing atomic-level evidence for two MIC6-EGF/MIC1 interaction sites; single lab, no functional follow-up in this paper\",\n      \"pmids\": [\"19636898\", \"19636901\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    }\n  ],\n  \"current_model\": \"TgMIC6 is a type I transmembrane EGF domain-containing micronemal protein that acts as an escorter for soluble adhesins MIC1 and MIC4 to the micronemes (via a cytoplasmic tail sorting signal and EGF2/EGF3-mediated interaction with MIC1's galectin-like domain); upon secretion the complex bridges host cell receptors to the parasite, while the MIC6 cytoplasmic tail connects to the actomyosin motor via aldolase at W348; MIC6 is shed from the parasite surface by intramembrane cleavage within its transmembrane domain by ROM4; and MIC6's EGF domains activate host cell EGFR-Akt-mTOR signaling to suppress autophagy-mediated parasite killing.\"\n}\n```","stage2_raw":"```json\n{\n  \"mechanistic_narrative\": \"TgMIC6 is a type I transmembrane micronemal protein of Toxoplasma gondii that organizes and traffics a heterotrimeric adhesive complex used for host cell invasion [#0]. Through its lumenal EGF-like domains it recruits the soluble adhesin MIC1, which in turn binds MIC4 as passive cargo, and MIC6's cytoplasmic tail supplies the sorting signal that targets the assembled MIC1-MIC4-MIC6 complex to the micronemes [#0]. Structural work resolved this recruitment at atomic resolution: two analogous sites within the EGF2 and EGF3 domains of MIC6 each engage the C-terminal galectin-like domain of MIC1, and this MIC1 interaction stabilizes MIC6 and provides quality control for exit from early secretory compartments [#4, #5]. During transport MIC6 is proteolytically matured at its N-terminus, and upon microneme discharge at the parasite surface it is shed by regulated intramembrane cleavage within its transmembrane domain at a conserved apicomplexan motif by the rhomboid protease ROM4 [#1, #2, #9]. The MIC6 cytoplasmic tail links the adhesive complex to the actomyosin invasion motor by binding aldolase and the parasite cytoskeleton via a critical tryptophan residue W348, although this aldolase interaction is dispensable for invasion [#6, #7, #8]. Beyond its role in invasion, MIC6 is a secreted virulence effector: its EGF domains activate host EGFR-Akt-mTOR signaling to suppress autophagy-mediated killing of the parasite, and knockout reduces virulence in vivo [#10, #11].\",\n  \"teleology\": [\n    {\n      \"year\": 2001,\n      \"claim\": \"Established that MIC6 is not merely a surface adhesin but the transmembrane escorter that traffics the soluble adhesins MIC1 and MIC4 to the micronemes, defining the architecture of an adhesive complex.\",\n      \"evidence\": \"Reciprocal gene disruption of MIC1/MIC4/MIC6, domain mapping and secretory pathway analysis in T. gondii\",\n      \"pmids\": [\"11157983\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Molecular identity of the EGF domain(s) mediating MIC1 binding not yet resolved\", \"Cytoplasmic tail sorting signal not mapped to specific residues\"],\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2002,\n      \"claim\": \"Defined MIC6 as a type I membrane protein subject to two distinct proteolytic events — N-terminal maturation and surface intramembrane cleavage — separating trafficking maturation from adhesin shedding.\",\n      \"evidence\": \"Site-specific mutagenesis of cleavage sites, pulse-chase, fractionation and fusion protein assays in T. gondii\",\n      \"pmids\": [\"11861763\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Protease responsible for intramembrane cleavage not identified\", \"Functional consequence of shedding for invasion not tested\"],\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2002,\n      \"claim\": \"Localized the intramembrane cleavage to a conserved IA\\u2193GG motif within the transmembrane domain and showed the cleavage machinery (MPP1) is constitutively active at the surface and recognizes the TM domain independent of the ectodomain.\",\n      \"evidence\": \"Site-directed TM-domain mutagenesis and chimeric SAG1-TM fusion cleavage assays in T. gondii\",\n      \"pmids\": [\"11927542\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"MPP1 enzyme not yet identified as a specific protease\", \"Regulation of cleavage timing during discharge unresolved\"],\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2005,\n      \"claim\": \"Identified rhomboid proteases as candidate MPP1 enzymes for microneme TM-domain cleavage, narrowing the search for the physiological MIC6 sheddase.\",\n      \"evidence\": \"Heterologous rhomboid cleavage assays with chimeric MIC TM-domain substrates in T. gondii\",\n      \"pmids\": [\"15913633\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"MIC6 transmembrane domain specifically not tested (only MIC2/MIC12)\", \"In vivo protease responsible for MIC6 shedding not established\"],\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2005,\n      \"claim\": \"Provided the structural and functional basis for complex quality control by showing the MIC1 galectin-like domain binds and stabilizes MIC6, coupling assembly to secretory exit.\",\n      \"evidence\": \"Crystal structure of MIC1 C-terminal domain with binding, immunofluorescence and invasion assays in T. gondii\",\n      \"pmids\": [\"16166092\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"MIC6 residues contacting MIC1 not yet defined\", \"Stoichiometry of the assembled complex not addressed\"],\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2008,\n      \"claim\": \"Resolved the MIC6-MIC1 interface at atomic resolution, revealing two analogous MIC1-binding sites in the EGF2 and EGF3 domains of MIC6 and defining a new mode of EGF domain recognition.\",\n      \"evidence\": \"NMR solution structure of the MIC6-MIC1 complex with resonance assignments, plus immunofluorescence and invasion assays in T. gondii\",\n      \"pmids\": [\"18818666\", \"19636898\", \"19636901\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Whether both EGF sites act cooperatively in vivo not resolved\", \"Contribution of each site to receptor recognition versus complex stability not disentangled\"],\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2009,\n      \"claim\": \"Connected the adhesive complex to the invasion motor by showing the MIC6 cytoplasmic tail binds aldolase and the parasite cytoskeleton.\",\n      \"evidence\": \"GST pulldown of the MIC6 cytoplasmic tail with tachyzoite lysate and recombinant aldolase in T. gondii\",\n      \"pmids\": [\"19308454\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Single-lab pulldown without genetic confirmation of functional relevance\", \"Aldolase-binding residues not yet mapped\"],\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2010,\n      \"claim\": \"Tested the functional necessity of the aldolase link and found it dispensable for invasion, distinguishing MIC6 from AMA1 and pointing to ectodomain-mediated interactions for some trafficking steps.\",\n      \"evidence\": \"Mutagenesis of aldolase-binding residues with invasion and rhomboid cleavage assays in T. gondii\",\n      \"pmids\": [\"20545864\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Identity of the ectodomain-interacting trafficking partners unknown\", \"Redundant motor-linkage mechanisms not identified\"],\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2014,\n      \"claim\": \"Pinpointed the aldolase-binding determinant to tryptophan W348 in the MIC6 cytoplasmic tail.\",\n      \"evidence\": \"Site-directed W348V mutagenesis with GST pulldown against parasite lysate and recombinant aldolase in T. gondii\",\n      \"pmids\": [\"25223060\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"In vitro binding assay only; in vivo consequence of W348V not established\", \"Single method set from a single lab\"],\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2015,\n      \"claim\": \"Identified ROM4 as the physiological rhomboid protease that sheds MIC6 (and MIC2), linking surface intramembrane cleavage to the switch from attachment to productive invasion.\",\n      \"evidence\": \"Cre-mediated ROM4 knockout and CRISPR ROM5 knockout with substrate cleavage, motility and invasion assays in T. gondii\",\n      \"pmids\": [\"25846828\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Whether ROM4 is the sole MIC6 sheddase not fully excluded\", \"Structural basis of ROM4 substrate selection for MIC6 not addressed\"],\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2013,\n      \"claim\": \"Revealed a second, effector role for MIC6 beyond adhesion: its EGF domains directly activate host EGFR-Akt signaling to block autophagic targeting of the vacuole and prevent parasite killing.\",\n      \"evidence\": \"MIC1/MIC3 knockouts deficient in EGF-MIC secretion, recombinant MIC6 stimulation, EGFR/Akt readouts, LC3 and parasite killing assays in T. gondii\",\n      \"pmids\": [\"24367261\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Direct MIC6-EGFR binding interface not mapped\", \"Whether the same EGF sites used for MIC1 binding engage EGFR unresolved\"],\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Established MIC6 as an in vivo virulence factor in the Chinese 1 WH3 strain, acting through EGFR-Akt-mTOR-mediated autophagy suppression and contributing to evasion of CD40L-dependent immunity.\",\n      \"evidence\": \"CRISPR/Cas9 MIC6 knockout in WH3, mouse infection, cytokine and proliferation assays, and CD40L depletion in T. gondii WH3\",\n      \"pmids\": [\"39116491\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No direct biochemical confirmation of the signaling mechanism in this strain\", \"Relative contribution of adhesion versus immune-evasion roles to virulence not separated\"],\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"WH3\"}]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How MIC6's EGF domains partition between their intramolecular role in MIC1 binding/complex assembly and their extracellular role in host EGFR activation remains unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Low\",\n      \"gaps\": [\"No structural map of a MIC6-EGFR interaction\", \"Ectodomain trafficking partners inferred but unidentified\", \"Whether shed versus membrane-bound MIC6 mediates EGFR signaling not determined\"],\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0005102 signaling receptor binding\", \"supporting_discovery_ids\": [10], \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]},\n      {\"term_id\": \"GO:0050839 cell adhesion molecule binding\", \"supporting_discovery_ids\": [0, 4, 5], \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]},\n      {\"term_id\": \"GO:0045296 cadherin binding\", \"supporting_discovery_ids\": [6, 8], \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0020009 microneme\", \"supporting_discovery_ids\": [0, 1], \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]},\n      {\"term_id\": \"GO:0016021 integral component of membrane\", \"supporting_discovery_ids\": [1, 2], \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]},\n      {\"term_id\": \"GO:0009986 cell surface\", \"supporting_discovery_ids\": [2, 9], \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"GO:0044409 symbiont entry into host cell\", \"supporting_discovery_ids\": [0, 5, 9], \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]},\n      {\"term_id\": \"GO:0038127 ERBB signaling pathway\", \"supporting_discovery_ids\": [10, 11], \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]},\n      {\"term_id\": \"GO:0010507 negative regulation of autophagy\", \"supporting_discovery_ids\": [10, 11], \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]}\n    ],\n    \"complexes\": [\n      \"MIC1-MIC4-MIC6 adhesive complex\"\n    ],\n    \"partners\": [\n      \"MIC1 (galectin-like domain binds MIC6 EGF2/EGF3)\",\n      \"MIC4 (passive cargo, binds MIC1)\",\n      \"aldolase (binds MIC6 cytoplasmic tail via W348)\",\n      \"parasite cytoskeleton / actomyosin motor\",\n      \"ROM4 (rhomboid protease sheddase)\",\n      \"host EGFR\"\n    ],\n    \"other_free_text\": [\n      \"N-terminal proteolytic maturation occurs probably in the trans-Golgi network [#1]\",\n      \"Intramembrane cleavage occurs at a conserved IA\\u2193GG motif within the transmembrane domain [#2]\",\n      \"MPP1/rhomboid activity is constitutively active at the parasite surface and recognizes the TM domain independent of the ectodomain [#2]\",\n      \"Aldolase binding is dispensable for invasion, unlike AMA1 [#7]\",\n      \"In WH3 strain, MIC6 knockout reduces virulence and CD40L-mediated immunity partially restores control [#11]\"\n    ]\n  },\n  \"strain_conflicts\": []\n}\n```","audit_flag":null,"strains":[{"strain":"ME49","gene_id":"TGME49_218520","name":"MIC6","product":"microneme protein MIC6","uniprot_acc":"S8EUN7","chromosome":"TGME49_chrXII","start_pos":1477888},{"strain":"GT1","gene_id":"TGGT1_218520","name":null,"product":"microneme protein MIC6","uniprot_acc":null,"chromosome":"TGGT1_chrXII","start_pos":1418869},{"strain":"RH88","gene_id":"TGRH88_058880","name":null,"product":"microneme protein MIC6","uniprot_acc":null,"chromosome":"CM023093","start_pos":1490662},{"strain":"VEG","gene_id":"TGVEG_218520","name":null,"product":"microneme protein MIC6","uniprot_acc":"B9QLZ0","chromosome":"TGVEG_chrXII","start_pos":1451866}]}