{"gene":"TG_214940","gene_symbol":"M2AP","run_date":"2026-09-10T21:09:19","timeline":{"discoveries":[{"year":2001,"finding":"TgM2AP physically associates with TgMIC2, forming a complex within 15 min of synthesis. M2AP remains associated with MIC2 in the micronemes, on the parasite surface during invasion, and in the culture medium after release. M2AP is proteolytically processed: its propeptide is removed during transit through the Golgi, and a second cleavage occurs on the parasite surface after discharge from micronemes.","method":"Co-immunoprecipitation, pulse-chase labeling, immunofluorescence, immunoelectron microscopy","journal":"Molecular microbiology","confidence":"High","confidence_rationale":"Tier 2 / Strong — reciprocal co-IP with multiple orthogonal methods (Co-IP, pulse-chase, IEM), replicated in subsequent papers","pmids":["11532123"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2003,"finding":"Disruption of M2AP (knockout) caused >80% impairment in host cell entry. MIC2 partially accumulated in the ER and Golgi in M2AP-KO parasites, and rapid secretion of MIC2 upon host cell attachment was abolished, demonstrating that M2AP is required for correct trafficking and secretion of MIC2.","method":"Genetic knockout, immunofluorescence, invasion assays, secretion assays","journal":"The EMBO journal","confidence":"High","confidence_rationale":"Tier 2 / Strong — clean genetic KO with multiple orthogonal phenotypic readouts (invasion efficiency, MIC2 localization, secretion assay)","pmids":["12727875"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2003,"finding":"MIC2 and M2AP form a stable hexameric complex (~450 kDa) consisting of three alpha-beta dimers, as determined by native blue gels and gel filtration. The cytoplasmic C-domain of MIC2 is not required for protein trafficking or secretion, and mutant MIC2 lacking this domain is escorted to micronemes by association with endogenous wild-type MIC2.","method":"Native PAGE (blue native gels), gel filtration chromatography, transgenic parasite expression","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 1 / Moderate — biochemical reconstitution of complex stoichiometry using two orthogonal biophysical methods in a single focused study","pmids":["14670959"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2006,"finding":"Conditional suppression of MIC2 caused mistrafficking of M2AP, demonstrating mutual dependence: MIC2 is required for correct M2AP sorting to the micronemes, and M2AP is required for efficient MIC2 trafficking and secretion. MIC2-deficient parasites showed markedly defective host-cell attachment, loss of helical gliding motility, and were unable to establish lethal infection in mice.","method":"Conditional (anhydrotetracycline-regulated) expression system, knockout, immunofluorescence, invasion/attachment assays, murine infection model","journal":"PLoS pathogens","confidence":"High","confidence_rationale":"Tier 2 / Strong — conditional KO system with multiple orthogonal readouts replicated across labs","pmids":["16933991"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2006,"finding":"The M2AP propeptide and its proteolytic removal influence distinct aspects of MIC2-M2AP trafficking and function. ProM2AP traffics through endosomal compartments; deletion of the propeptide leads to defective trafficking near this site causing aberrant MIC2 processing and decreased secretion. Mutation of cleavage-site residues allows normal localization but reduces complex stability and secretion from micronemes. Both manipulations impair invasion and reduce virulence in vivo.","method":"Propeptide deletion and cleavage-site mutagenesis, immunofluorescence, invasion assays, in vivo murine virulence model","journal":"Molecular biology of the cell","confidence":"High","confidence_rationale":"Tier 2 / Strong — site-directed mutagenesis combined with multiple orthogonal assays (localization, secretion, invasion, in vivo) in a single study","pmids":["16914527"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2014,"finding":"The NMR solution structure of the globular domain of M2AP was solved; M2AP adopts a modified galectin fold similar to the C-terminal domain of MIC1. NMR and immunoprecipitation analyses showed that hydrophobic residues on one face of the M2AP galectin fold bind to the membrane-proximal sixth thrombospondin type I repeat domain (TSR6) of MIC2.","method":"NMR structure determination, immunoprecipitation","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 1 / Moderate — NMR structure with functional validation by immunoprecipitation, two orthogonal methods in one study","pmids":["25411252"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2014,"finding":"Crystal structures of proMIC2 and MIC2 N-terminal fragments (VWA + TSR1 domains) were solved. The MIC2-M2AP ectodomain complex is a highly elongated 1:1 monomer with M2AP bound to the TSR6 domain. The MIC2 VWA domain adopts a closed conformation in the crystal structure, and TSR1 contains a proline-rich disulfide-bonded pigtail loop overlapping the VWA domain.","method":"X-ray crystallography, biochemical binding assays","journal":"Proceedings of the National Academy of Sciences of the United States of America","confidence":"High","confidence_rationale":"Tier 1 / Strong — crystal structures of multiple domains with biochemical validation of complex stoichiometry","pmids":["24639528"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2023,"finding":"Crystal structures of M2AP alone and in complex with TSR6 of MIC2 were solved. TSR6 residue H620 is the hotspot at the center of the binding interface with M2AP. Residue Y602 of TSR6 is dynamic, equilibrating between layered and flipped-out states; M2AP binding shifts Y602 to the flipped-out state. The non-layered side of TSR6 mediates binding to M2AP.","method":"X-ray crystallography of M2AP alone and M2AP-TSR6 complex","journal":"Communications biology","confidence":"High","confidence_rationale":"Tier 1 / Moderate — crystal structures of both free and complexed forms with mutational mapping of hotspot residue","pmids":["37652989"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2011,"finding":"Forward targeting of M2AP to micronemes requires a valine residue at position +3 relative to signal peptidase cleavage in the propeptide. Mutagenesis of this valine abolished correct micronemal trafficking. Propeptide domains are functionally interchangeable between T. gondii MICs and with Eimeria tenella MIC5 propeptide, indicating a conserved mechanism.","method":"N-terminal deletion and point mutagenesis of propeptide, immunofluorescence-based trafficking assay","journal":"Traffic (Copenhagen, Denmark)","confidence":"High","confidence_rationale":"Tier 2 / Moderate — systematic mutagenesis identifying specific residue with interchangeability experiments across species","pmids":["21438967"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2008,"finding":"The M2AP propeptide functions as a forward-targeting element for micronemal trafficking. When the M2AP propeptide was exchanged for the MIC5 propeptide, correct trafficking was maintained, indicating propeptides are functionally interchangeable between microneme proteins.","method":"Propeptide exchange constructs, immunofluorescence localization","journal":"Biology of the cell","confidence":"Medium","confidence_rationale":"Tier 2 / Weak — single lab, functional propeptide swap experiment, single method","pmids":["17995454"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2005,"finding":"The M2AP propeptide is required for the MIC2-M2AP complex to exit from the early endosome. A cleavage-resistant M2AP mutant reached micronemes but could not be rapidly mobilized to the parasite surface. Both the propeptide deletion and cleavage-resistant mutants were unable to support normal parasite invasion and were partially attenuated in virulence. MIC2 was also shown to be required for correct M2AP sorting to micronemes.","method":"M2AP propeptide deletion and cleavage-resistant mutant expression in M2AP-KO background, conditional MIC2 expression, immunofluorescence, invasion assays, murine virulence model","journal":"Parasitology research","confidence":"High","confidence_rationale":"Tier 2 / Moderate — genetic complementation with defined mutants tested by multiple orthogonal methods including in vivo","pmids":["16385407"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2004,"finding":"An M2AP deletion mutant (m2ap KO) was used to show that the MIC2 adhesin specifically contributes to calmidazolium-stimulated gliding motility, implicating the MIC2-M2AP complex in calcium-regulated gliding.","method":"Deletion mutant phenotypic analysis, gliding motility assay with calmidazolium stimulation","journal":"Journal of cell science","confidence":"Medium","confidence_rationale":"Tier 2 / Weak — single lab, genetic KO with pharmacological stimulation, specific pathway placement for MIC2-M2AP in Ca2+-regulated motility","pmids":["15507483"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2004,"finding":"In the absence of TgMIC2, TgM2AP was incorrectly processed and mistargeted to the parasitophorous vacuole instead of the micronemes, demonstrating that MIC2 is required for correct M2AP maturation and trafficking. EtMIC1 (Eimeria tenella ortholog of MIC2) could substitute for TgMIC2 to allow parasite survival but could not fully restore M2AP trafficking or invasion efficiency.","method":"Trans-genera complementation (EtMIC1/EtMIC2 introduced into T. gondii), TgMIC2 knockout, immunofluorescence, invasion assays","journal":"Cellular microbiology","confidence":"High","confidence_rationale":"Tier 2 / Strong — genetic KO complemented by ortholog reconstitution, multiple orthogonal assays, replicated finding on MIC2-M2AP interdependence","pmids":["15236644"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2010,"finding":"TgSUB1 (a GPI-anchored microneme subtilisin protease) is responsible for proteolytic trimming of M2AP on the parasite surface after secretion. Parasites lacking TgSUB1 fail to process M2AP (and MIC2, MIC4) after surface release, leading to decreased cell attachment, reduced gliding, and lower invasion rates.","method":"TgSUB1 knockout and complementation (including GPI-anchor deletion mutant), secretion/processing assays, invasion and attachment assays","journal":"Cellular microbiology","confidence":"High","confidence_rationale":"Tier 2 / Strong — clean KO with complementation controls, multiple orthogonal readouts for the specific processing event","pmids":["20678172"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":""}]}],"current_model":"M2AP (TgM2AP) is a microneme protein that forms a stable heterohexameric complex (3 αβ dimers, ~450 kDa) with the transmembrane adhesin MIC2 through its modified galectin fold binding to the sixth TSR domain (TSR6) of MIC2; M2AP's propeptide acts as a forward-targeting signal (requiring a conserved aliphatic residue at +3) for transit through endosomal compartments to the micronemes, where the propeptide is removed by a Golgi/post-Golgi protease, and after surface discharge the mature form is further trimmed by the GPI-anchored subtilisin TgSUB1; MIC2 and M2AP are mutually dependent for correct trafficking and secretion, and the MIC2-M2AP complex is essential for rapid Ca2+-triggered microneme secretion, productive gliding motility (connecting to the actomyosin motor via aldolase/GAC interactions with MIC2's cytoplasmic tail), host cell attachment, and efficient invasion."},"narrative":{"mechanistic_narrative":"M2AP (microneme protein 2-associated protein) is a soluble microneme protein of Toxoplasma gondii that partners with the transmembrane adhesin MIC2 to enable host-cell attachment and invasion [PMID:11532123, PMID:12727875]. The two proteins assemble co-translationally into a stable ~450 kDa hexameric complex composed of three αβ dimers [PMID:11532123, PMID:14670959]; M2AP adopts a modified galectin fold that binds the membrane-proximal sixth thrombospondin type I repeat (TSR6) of MIC2 through hydrophobic residues on one face, with TSR6 residue H620 forming the interface hotspot and M2AP binding shifting TSR6 residue Y602 to a flipped-out state [PMID:25411252, PMID:24639528, PMID:37652989]. MIC2 and M2AP are mutually dependent for correct secretory trafficking: loss of M2AP causes MIC2 to accumulate in the ER/Golgi and abolishes rapid attachment-triggered secretion, while loss of MIC2 causes M2AP to be mis-processed and mistargeted to the parasitophorous vacuole [PMID:12727875, PMID:16933991, PMID:15236644]. The M2AP propeptide acts as a forward-targeting signal—requiring a valine at position +3 relative to signal-peptidase cleavage—that routes the complex through endosomal compartments to the micronemes, and its proteolytic removal enables the complex to exit the early endosome and be mobilized to the surface; after Ca2+-triggered discharge the mature protein is further trimmed on the parasite surface by the GPI-anchored subtilisin TgSUB1 [PMID:16914527, PMID:21438967, PMID:16385407, PMID:20678172]. Genetic disruption of M2AP impairs host-cell entry by more than 80% and, together with MIC2, links the complex to calcium-regulated gliding motility that drives productive invasion [PMID:12727875, PMID:15507483].","teleology":[{"year":2001,"claim":"Establishing that M2AP is a bona fide partner of MIC2 defined the first molecular context for its function and revealed a two-step proteolytic maturation program.","evidence":"Co-immunoprecipitation, pulse-chase labeling and immunoelectron microscopy in T. gondii","pmids":["11532123"],"confidence":"High","gaps":["Stoichiometry and structural basis of the association not yet defined","Identity of the processing proteases unknown"],"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2003,"claim":"Genetic knockout and complex characterization showed M2AP is functionally required for MIC2 trafficking/secretion and invasion, and that the two proteins form a defined 450 kDa hexamer.","evidence":"Genetic knockout with invasion/secretion assays and native PAGE/gel filtration in T. gondii","pmids":["12727875","14670959"],"confidence":"High","gaps":["Molecular determinants of the MIC2-M2AP interface unresolved","How the complex triggers rapid secretion not defined"],"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2005,"claim":"Propeptide deletion and cleavage-resistant mutants demonstrated that the M2AP propeptide gates early-endosome exit and that its removal is needed for surface mobilization, defining a trafficking checkpoint.","evidence":"Complementation of M2AP-KO with defined propeptide mutants, conditional MIC2 expression, invasion and murine virulence assays in T. gondii","pmids":["16385407"],"confidence":"High","gaps":["Protease removing the propeptide not identified","Precise endosomal compartment traversed not molecularly defined"],"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2004,"claim":"Trans-genera complementation and MIC2-null analysis established the mutual dependence of MIC2 and M2AP for correct maturation and micronemal targeting, and placed the complex in calcium-regulated gliding.","evidence":"MIC2 knockout with Eimeria ortholog complementation, and m2ap deletion tested in calmidazolium-stimulated gliding assays in T. gondii","pmids":["15236644","15507483"],"confidence":"Medium","gaps":["Mechanistic link from complex to the actomyosin motor not yet defined","Ortholog substitution incomplete for invasion"],"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2006,"claim":"Conditional MIC2 suppression and detailed propeptide/cleavage-site mutagenesis dissected how distinct trafficking steps controlled by the propeptide affect complex stability, secretion, and virulence.","evidence":"Anhydrotetracycline-regulated conditional expression, site-directed mutagenesis with localization/secretion/invasion and in vivo virulence assays in T. gondii","pmids":["16933991","16914527"],"confidence":"High","gaps":["Molecular receptor recognizing the propeptide signal unknown","Coupling to helical gliding at the mechanistic level unresolved"],"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2008,"claim":"Propeptide-exchange experiments showed the propeptide is a portable, interchangeable forward-targeting element shared among microneme proteins.","evidence":"Propeptide swap constructs with immunofluorescence localization in T. gondii","pmids":["17995454"],"confidence":"Medium","gaps":["Single-method, single-lab finding","Specific sequence determinant within the propeptide not yet mapped"],"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2010,"claim":"Identification of TgSUB1 as the surface protease that trims M2AP (and MIC2/MIC4) after discharge assigned the second processing event to a specific enzyme with functional consequences for attachment and invasion.","evidence":"TgSUB1 knockout and complementation including GPI-anchor mutant, processing/attachment/invasion assays in T. gondii","pmids":["20678172"],"confidence":"High","gaps":["Functional purpose of surface trimming for adhesion mechanics not fully defined"],"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2011,"claim":"Mutagenesis pinpointed a valine at the +3 position of the propeptide as the essential residue for micronemal forward targeting, with conservation across genera.","evidence":"N-terminal deletion and point mutagenesis with immunofluorescence trafficking assays and cross-species interchangeability in T. gondii","pmids":["21438967"],"confidence":"High","gaps":["Trafficking machinery reading the +3 aliphatic residue not identified"],"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2014,"claim":"Solution and crystal structures defined the M2AP galectin fold and the elongated MIC2-M2AP ectodomain architecture, localizing M2AP binding to MIC2 TSR6.","evidence":"NMR of the M2AP globular domain plus immunoprecipitation, and X-ray crystallography of proMIC2/MIC2 N-terminal fragments with binding assays in T. gondii","pmids":["25411252","24639528"],"confidence":"High","gaps":["Atomic detail of the M2AP-TSR6 interface not yet resolved at this stage","Conformational role of the VWA domain in adhesion unclear"],"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2023,"claim":"Crystal structures of free M2AP and the M2AP-TSR6 complex mapped the interface hotspot (H620) and revealed a conformational switch of TSR6 Y602 upon M2AP binding.","evidence":"X-ray crystallography of M2AP alone and in complex with MIC2 TSR6 with mutational mapping in T. gondii","pmids":["37652989"],"confidence":"High","gaps":["Functional consequence of the Y602 conformational switch for adhesion or motor engagement not established"],"attribution":[{"species":"Toxoplasma gondii","strain":""}]}],"mechanism_profile":{"molecular_activity":[],"localization":[],"pathway":[],"complexes":["MIC2-M2AP hexameric complex (~450 kDa, three αβ dimers)"],"partners":["TGMIC2 (VIA TSR6, HOTSPOT H620)","TGSUB1 (SUBTILISIN PROTEASE THAT TRIMS MATURE M2AP ON THE PARASITE SURFACE)"],"other_free_text":["M2AP adopts a modified galectin fold that binds MIC2 TSR6; M2AP binding shifts TSR6 residue Y602 to a flipped-out state [#5, #7]","The M2AP propeptide is a forward-targeting signal requiring a valine at the +3 position; propeptide cleavage gates early-endosome exit [#8, #10]","MIC2 and M2AP are mutually dependent for correct secretory trafficking and secretion [#1, #3, #12]","MIC2 (used as a marker) connects to the actomyosin motor via the glideosome-associated connector GAC and is subject to O-fucosylation by POFUT2; these findings concern MIC2 rather than M2AP directly [#14, #15, #16]"]},"strain_conflicts":[]},"prefetch_data":{},"corpus_meta":[{"pmid":"12727875","id":"PMC_12727875","title":"Rapid invasion of host cells by Toxoplasma requires secretion of the MIC2-M2AP adhesive protein complex.","date":"2003","source":"The EMBO journal","url":"https://pubmed.ncbi.nlm.nih.gov/12727875","citation_count":206,"is_preprint":false},{"pmid":"16933991","id":"PMC_16933991","title":"Toxoplasma MIC2 is a major determinant of invasion and virulence.","date":"2006","source":"PLoS pathogens","url":"https://pubmed.ncbi.nlm.nih.gov/16933991","citation_count":171,"is_preprint":false},{"pmid":"11532123","id":"PMC_11532123","title":"TgM2AP participates in Toxoplasma gondii invasion of host cells and is tightly associated with the adhesive protein TgMIC2.","date":"2001","source":"Molecular microbiology","url":"https://pubmed.ncbi.nlm.nih.gov/11532123","citation_count":97,"is_preprint":false},{"pmid":"15507483","id":"PMC_15507483","title":"Calcium-mediated protein secretion 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\"finding\": \"TgM2AP physically associates with TgMIC2, forming a complex within 15 min of synthesis. M2AP remains associated with MIC2 in the micronemes, on the parasite surface during invasion, and in the culture medium after release. M2AP is proteolytically processed: its propeptide is removed during transit through the Golgi, and a second cleavage occurs on the parasite surface after discharge from micronemes.\",\n      \"method\": \"Co-immunoprecipitation, pulse-chase labeling, immunofluorescence, immunoelectron microscopy\",\n      \"journal\": \"Molecular microbiology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — reciprocal co-IP with multiple orthogonal methods (Co-IP, pulse-chase, IEM), replicated in subsequent papers\",\n      \"pmids\": [\"11532123\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2003,\n      \"finding\": \"Disruption of M2AP (knockout) caused >80% impairment in host cell entry. MIC2 partially accumulated in the ER and Golgi in M2AP-KO parasites, and rapid secretion of MIC2 upon host cell attachment was abolished, demonstrating that M2AP is required for correct trafficking and secretion of MIC2.\",\n      \"method\": \"Genetic knockout, immunofluorescence, invasion assays, secretion assays\",\n      \"journal\": \"The EMBO journal\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — clean genetic KO with multiple orthogonal phenotypic readouts (invasion efficiency, MIC2 localization, secretion assay)\",\n      \"pmids\": [\"12727875\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2003,\n      \"finding\": \"MIC2 and M2AP form a stable hexameric complex (~450 kDa) consisting of three alpha-beta dimers, as determined by native blue gels and gel filtration. The cytoplasmic C-domain of MIC2 is not required for protein trafficking or secretion, and mutant MIC2 lacking this domain is escorted to micronemes by association with endogenous wild-type MIC2.\",\n      \"method\": \"Native PAGE (blue native gels), gel filtration chromatography, transgenic parasite expression\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — biochemical reconstitution of complex stoichiometry using two orthogonal biophysical methods in a single focused study\",\n      \"pmids\": [\"14670959\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2006,\n      \"finding\": \"Conditional suppression of MIC2 caused mistrafficking of M2AP, demonstrating mutual dependence: MIC2 is required for correct M2AP sorting to the micronemes, and M2AP is required for efficient MIC2 trafficking and secretion. MIC2-deficient parasites showed markedly defective host-cell attachment, loss of helical gliding motility, and were unable to establish lethal infection in mice.\",\n      \"method\": \"Conditional (anhydrotetracycline-regulated) expression system, knockout, immunofluorescence, invasion/attachment assays, murine infection model\",\n      \"journal\": \"PLoS pathogens\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — conditional KO system with multiple orthogonal readouts replicated across labs\",\n      \"pmids\": [\"16933991\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2006,\n      \"finding\": \"The M2AP propeptide and its proteolytic removal influence distinct aspects of MIC2-M2AP trafficking and function. ProM2AP traffics through endosomal compartments; deletion of the propeptide leads to defective trafficking near this site causing aberrant MIC2 processing and decreased secretion. Mutation of cleavage-site residues allows normal localization but reduces complex stability and secretion from micronemes. Both manipulations impair invasion and reduce virulence in vivo.\",\n      \"method\": \"Propeptide deletion and cleavage-site mutagenesis, immunofluorescence, invasion assays, in vivo murine virulence model\",\n      \"journal\": \"Molecular biology of the cell\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — site-directed mutagenesis combined with multiple orthogonal assays (localization, secretion, invasion, in vivo) in a single study\",\n      \"pmids\": [\"16914527\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"The NMR solution structure of the globular domain of M2AP was solved; M2AP adopts a modified galectin fold similar to the C-terminal domain of MIC1. NMR and immunoprecipitation analyses showed that hydrophobic residues on one face of the M2AP galectin fold bind to the membrane-proximal sixth thrombospondin type I repeat domain (TSR6) of MIC2.\",\n      \"method\": \"NMR structure determination, immunoprecipitation\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — NMR structure with functional validation by immunoprecipitation, two orthogonal methods in one study\",\n      \"pmids\": [\"25411252\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"Crystal structures of proMIC2 and MIC2 N-terminal fragments (VWA + TSR1 domains) were solved. The MIC2-M2AP ectodomain complex is a highly elongated 1:1 monomer with M2AP bound to the TSR6 domain. The MIC2 VWA domain adopts a closed conformation in the crystal structure, and TSR1 contains a proline-rich disulfide-bonded pigtail loop overlapping the VWA domain.\",\n      \"method\": \"X-ray crystallography, biochemical binding assays\",\n      \"journal\": \"Proceedings of the National Academy of Sciences of the United States of America\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — crystal structures of multiple domains with biochemical validation of complex stoichiometry\",\n      \"pmids\": [\"24639528\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"Crystal structures of M2AP alone and in complex with TSR6 of MIC2 were solved. TSR6 residue H620 is the hotspot at the center of the binding interface with M2AP. Residue Y602 of TSR6 is dynamic, equilibrating between layered and flipped-out states; M2AP binding shifts Y602 to the flipped-out state. The non-layered side of TSR6 mediates binding to M2AP.\",\n      \"method\": \"X-ray crystallography of M2AP alone and M2AP-TSR6 complex\",\n      \"journal\": \"Communications biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — crystal structures of both free and complexed forms with mutational mapping of hotspot residue\",\n      \"pmids\": [\"37652989\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"Forward targeting of M2AP to micronemes requires a valine residue at position +3 relative to signal peptidase cleavage in the propeptide. Mutagenesis of this valine abolished correct micronemal trafficking. Propeptide domains are functionally interchangeable between T. gondii MICs and with Eimeria tenella MIC5 propeptide, indicating a conserved mechanism.\",\n      \"method\": \"N-terminal deletion and point mutagenesis of propeptide, immunofluorescence-based trafficking assay\",\n      \"journal\": \"Traffic (Copenhagen, Denmark)\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — systematic mutagenesis identifying specific residue with interchangeability experiments across species\",\n      \"pmids\": [\"21438967\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2008,\n      \"finding\": \"The M2AP propeptide functions as a forward-targeting element for micronemal trafficking. When the M2AP propeptide was exchanged for the MIC5 propeptide, correct trafficking was maintained, indicating propeptides are functionally interchangeable between microneme proteins.\",\n      \"method\": \"Propeptide exchange constructs, immunofluorescence localization\",\n      \"journal\": \"Biology of the cell\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Weak — single lab, functional propeptide swap experiment, single method\",\n      \"pmids\": [\"17995454\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2005,\n      \"finding\": \"The M2AP propeptide is required for the MIC2-M2AP complex to exit from the early endosome. A cleavage-resistant M2AP mutant reached micronemes but could not be rapidly mobilized to the parasite surface. Both the propeptide deletion and cleavage-resistant mutants were unable to support normal parasite invasion and were partially attenuated in virulence. MIC2 was also shown to be required for correct M2AP sorting to micronemes.\",\n      \"method\": \"M2AP propeptide deletion and cleavage-resistant mutant expression in M2AP-KO background, conditional MIC2 expression, immunofluorescence, invasion assays, murine virulence model\",\n      \"journal\": \"Parasitology research\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genetic complementation with defined mutants tested by multiple orthogonal methods including in vivo\",\n      \"pmids\": [\"16385407\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2004,\n      \"finding\": \"An M2AP deletion mutant (m2ap KO) was used to show that the MIC2 adhesin specifically contributes to calmidazolium-stimulated gliding motility, implicating the MIC2-M2AP complex in calcium-regulated gliding.\",\n      \"method\": \"Deletion mutant phenotypic analysis, gliding motility assay with calmidazolium stimulation\",\n      \"journal\": \"Journal of cell science\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Weak — single lab, genetic KO with pharmacological stimulation, specific pathway placement for MIC2-M2AP in Ca2+-regulated motility\",\n      \"pmids\": [\"15507483\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2004,\n      \"finding\": \"In the absence of TgMIC2, TgM2AP was incorrectly processed and mistargeted to the parasitophorous vacuole instead of the micronemes, demonstrating that MIC2 is required for correct M2AP maturation and trafficking. EtMIC1 (Eimeria tenella ortholog of MIC2) could substitute for TgMIC2 to allow parasite survival but could not fully restore M2AP trafficking or invasion efficiency.\",\n      \"method\": \"Trans-genera complementation (EtMIC1/EtMIC2 introduced into T. gondii), TgMIC2 knockout, immunofluorescence, invasion assays\",\n      \"journal\": \"Cellular microbiology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — genetic KO complemented by ortholog reconstitution, multiple orthogonal assays, replicated finding on MIC2-M2AP interdependence\",\n      \"pmids\": [\"15236644\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"TgSUB1 (a GPI-anchored microneme subtilisin protease) is responsible for proteolytic trimming of M2AP on the parasite surface after secretion. Parasites lacking TgSUB1 fail to process M2AP (and MIC2, MIC4) after surface release, leading to decreased cell attachment, reduced gliding, and lower invasion rates.\",\n      \"method\": \"TgSUB1 knockout and complementation (including GPI-anchor deletion mutant), secretion/processing assays, invasion and attachment assays\",\n      \"journal\": \"Cellular microbiology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — clean KO with complementation controls, multiple orthogonal readouts for the specific processing event\",\n      \"pmids\": [\"20678172\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"The glideosome-associated connector (GAC/TgGAC) specifically associates with the transmembrane adhesin TgMIC2, bridging micronemal adhesins to the actomyosin system. GAC localizes to the apical pole and is required for gliding motility, invasion, and egress.\",\n      \"method\": \"Co-immunoprecipitation, immunofluorescence, conditional knockout\",\n      \"journal\": \"Cell host & microbe\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — Co-IP demonstrating specific MIC2-GAC interaction supported by KO phenotyping with multiple readouts, single lab\",\n      \"pmids\": [\"27978434\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"O-fucosylation of the TSR domains of MIC2 by protein O-fucosyltransferase 2 (POFUT2) is required for efficient processing of MIC2 and for normal parasite invasion. Disruption of POFUT2 or the GDP-fucose transporter (NST2) caused loss of MIC2 O-fucosylation, markedly reduced MIC2 cellular levels, and in 10-15% of vacuoles caused MIC2 to accumulate earlier in the secretory pathway rather than in micronemes. Invasion and attachment defects were comparable to Δmic2.\",\n      \"method\": \"Gene knockout of POFUT2 and NST2, MS analysis of glycosylation sites, immunofluorescence, invasion/attachment assays\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genetic KO combined with MS-based glycosite mapping and multiple phenotypic assays in a single study\",\n      \"pmids\": [\"30538131\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"Micronemes (tracked using MIC2 as a marker) are recycled from mother to daughter parasites via a highly dynamic F-actin network during intracellular replication. This recycling is F-actin-dependent, while de novo synthesis of micronemes is F-actin-independent. The residual body acts as a storage and sorting station for micronemal vesicles.\",\n      \"method\": \"Dual labeling of MIC2, super-resolution microscopy, F-actin perturbation\",\n      \"journal\": \"Nature communications\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — super-resolution live imaging with pharmacological perturbation, MIC2 used as marker for organelle recycling pathway\",\n      \"pmids\": [\"31519913\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    }\n  ],\n  \"current_model\": \"M2AP (TgM2AP) is a microneme protein that forms a stable heterohexameric complex (3 αβ dimers, ~450 kDa) with the transmembrane adhesin MIC2 through its modified galectin fold binding to the sixth TSR domain (TSR6) of MIC2; M2AP's propeptide acts as a forward-targeting signal (requiring a conserved aliphatic residue at +3) for transit through endosomal compartments to the micronemes, where the propeptide is removed by a Golgi/post-Golgi protease, and after surface discharge the mature form is further trimmed by the GPI-anchored subtilisin TgSUB1; MIC2 and M2AP are mutually dependent for correct trafficking and secretion, and the MIC2-M2AP complex is essential for rapid Ca2+-triggered microneme secretion, productive gliding motility (connecting to the actomyosin motor via aldolase/GAC interactions with MIC2's cytoplasmic tail), host cell attachment, and efficient invasion.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"M2AP (microneme protein 2-associated protein) is a soluble microneme protein of Toxoplasma gondii that partners with the transmembrane adhesin MIC2 to enable host-cell attachment and invasion [#0, #1]. The two proteins assemble co-translationally into a stable ~450 kDa hexameric complex composed of three \\u03b1\\u03b2 dimers [#0, #2]; M2AP adopts a modified galectin fold that binds the membrane-proximal sixth thrombospondin type I repeat (TSR6) of MIC2 through hydrophobic residues on one face, with TSR6 residue H620 forming the interface hotspot and M2AP binding shifting TSR6 residue Y602 to a flipped-out state [#5, #6, #7]. MIC2 and M2AP are mutually dependent for correct secretory trafficking: loss of M2AP causes MIC2 to accumulate in the ER/Golgi and abolishes rapid attachment-triggered secretion, while loss of MIC2 causes M2AP to be mis-processed and mistargeted to the parasitophorous vacuole [#1, #3, #12]. The M2AP propeptide acts as a forward-targeting signal\\u2014requiring a valine at position +3 relative to signal-peptidase cleavage\\u2014that routes the complex through endosomal compartments to the micronemes, and its proteolytic removal enables the complex to exit the early endosome and be mobilized to the surface; after Ca2+-triggered discharge the mature protein is further trimmed on the parasite surface by the GPI-anchored subtilisin TgSUB1 [#4, #8, #10, #13]. Genetic disruption of M2AP impairs host-cell entry by more than 80% and, together with MIC2, links the complex to calcium-regulated gliding motility that drives productive invasion [#1, #11].\",\n  \"teleology\": [\n    {\n      \"year\": 2001,\n      \"claim\": \"Establishing that M2AP is a bona fide partner of MIC2 defined the first molecular context for its function and revealed a two-step proteolytic maturation program.\",\n      \"evidence\": \"Co-immunoprecipitation, pulse-chase labeling and immunoelectron microscopy in T. gondii\",\n      \"pmids\": [\"11532123\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Stoichiometry and structural basis of the association not yet defined\", \"Identity of the processing proteases unknown\"],\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2003,\n      \"claim\": \"Genetic knockout and complex characterization showed M2AP is functionally required for MIC2 trafficking/secretion and invasion, and that the two proteins form a defined 450 kDa hexamer.\",\n      \"evidence\": \"Genetic knockout with invasion/secretion assays and native PAGE/gel filtration in T. gondii\",\n      \"pmids\": [\"12727875\", \"14670959\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Molecular determinants of the MIC2-M2AP interface unresolved\", \"How the complex triggers rapid secretion not defined\"],\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2005,\n      \"claim\": \"Propeptide deletion and cleavage-resistant mutants demonstrated that the M2AP propeptide gates early-endosome exit and that its removal is needed for surface mobilization, defining a trafficking checkpoint.\",\n      \"evidence\": \"Complementation of M2AP-KO with defined propeptide mutants, conditional MIC2 expression, invasion and murine virulence assays in T. gondii\",\n      \"pmids\": [\"16385407\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Protease removing the propeptide not identified\", \"Precise endosomal compartment traversed not molecularly defined\"],\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2004,\n      \"claim\": \"Trans-genera complementation and MIC2-null analysis established the mutual dependence of MIC2 and M2AP for correct maturation and micronemal targeting, and placed the complex in calcium-regulated gliding.\",\n      \"evidence\": \"MIC2 knockout with Eimeria ortholog complementation, and m2ap deletion tested in calmidazolium-stimulated gliding assays in T. gondii\",\n      \"pmids\": [\"15236644\", \"15507483\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Mechanistic link from complex to the actomyosin motor not yet defined\", \"Ortholog substitution incomplete for invasion\"],\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2006,\n      \"claim\": \"Conditional MIC2 suppression and detailed propeptide/cleavage-site mutagenesis dissected how distinct trafficking steps controlled by the propeptide affect complex stability, secretion, and virulence.\",\n      \"evidence\": \"Anhydrotetracycline-regulated conditional expression, site-directed mutagenesis with localization/secretion/invasion and in vivo virulence assays in T. gondii\",\n      \"pmids\": [\"16933991\", \"16914527\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Molecular receptor recognizing the propeptide signal unknown\", \"Coupling to helical gliding at the mechanistic level unresolved\"],\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2008,\n      \"claim\": \"Propeptide-exchange experiments showed the propeptide is a portable, interchangeable forward-targeting element shared among microneme proteins.\",\n      \"evidence\": \"Propeptide swap constructs with immunofluorescence localization in T. gondii\",\n      \"pmids\": [\"17995454\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Single-method, single-lab finding\", \"Specific sequence determinant within the propeptide not yet mapped\"],\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2010,\n      \"claim\": \"Identification of TgSUB1 as the surface protease that trims M2AP (and MIC2/MIC4) after discharge assigned the second processing event to a specific enzyme with functional consequences for attachment and invasion.\",\n      \"evidence\": \"TgSUB1 knockout and complementation including GPI-anchor mutant, processing/attachment/invasion assays in T. gondii\",\n      \"pmids\": [\"20678172\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Functional purpose of surface trimming for adhesion mechanics not fully defined\"],\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2011,\n      \"claim\": \"Mutagenesis pinpointed a valine at the +3 position of the propeptide as the essential residue for micronemal forward targeting, with conservation across genera.\",\n      \"evidence\": \"N-terminal deletion and point mutagenesis with immunofluorescence trafficking assays and cross-species interchangeability in T. gondii\",\n      \"pmids\": [\"21438967\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Trafficking machinery reading the +3 aliphatic residue not identified\"],\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2014,\n      \"claim\": \"Solution and crystal structures defined the M2AP galectin fold and the elongated MIC2-M2AP ectodomain architecture, localizing M2AP binding to MIC2 TSR6.\",\n      \"evidence\": \"NMR of the M2AP globular domain plus immunoprecipitation, and X-ray crystallography of proMIC2/MIC2 N-terminal fragments with binding assays in T. gondii\",\n      \"pmids\": [\"25411252\", \"24639528\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Atomic detail of the M2AP-TSR6 interface not yet resolved at this stage\", \"Conformational role of the VWA domain in adhesion unclear\"],\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Crystal structures of free M2AP and the M2AP-TSR6 complex mapped the interface hotspot (H620) and revealed a conformational switch of TSR6 Y602 upon M2AP binding.\",\n      \"evidence\": \"X-ray crystallography of M2AP alone and in complex with MIC2 TSR6 with mutational mapping in T. gondii\",\n      \"pmids\": [\"37652989\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Functional consequence of the Y602 conformational switch for adhesion or motor engagement not established\"],\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How the mature MIC2-M2AP complex mechanically transduces adhesion into the actomyosin-driven motility that powers invasion remains incompletely defined.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct role of M2AP (versus MIC2 alone) in engaging GAC/aldolase and the motor unresolved\", \"Regulatory input controlling the timing of surface trimming and complex disassembly unknown\"],\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0005515\", \"supporting_discovery_ids\": [0, 5, 6, 7], \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0020009\", \"supporting_discovery_ids\": [0, 1, 3], \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]},\n      {\"term_id\": \"GO:0009986\", \"supporting_discovery_ids\": [0, 13], \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]},\n      {\"term_id\": \"GO:0005768\", \"supporting_discovery_ids\": [4, 10], \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"GO:0044409\", \"supporting_discovery_ids\": [1, 3, 11], \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]},\n      {\"term_id\": \"GO:0071702\", \"supporting_discovery_ids\": [4, 8, 10], \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]}\n    ],\n    \"complexes\": [\n      \"MIC2-M2AP hexameric complex (~450 kDa, three \\u03b1\\u03b2 dimers)\"\n    ],\n    \"partners\": [\n      \"TgMIC2 (via TSR6, hotspot H620)\",\n      \"TgSUB1 (subtilisin protease that trims mature M2AP on the parasite surface)\"\n    ],\n    \"other_free_text\": [\n      \"M2AP adopts a modified galectin fold that binds MIC2 TSR6; M2AP binding shifts TSR6 residue Y602 to a flipped-out state [#5, #7]\",\n      \"The M2AP propeptide is a forward-targeting signal requiring a valine at the +3 position; propeptide cleavage gates early-endosome exit [#8, #10]\",\n      \"MIC2 and M2AP are mutually dependent for correct secretory trafficking and secretion [#1, #3, #12]\",\n      \"MIC2 (used as a marker) connects to the actomyosin motor via the glideosome-associated connector GAC and is subject to O-fucosylation by POFUT2; these findings concern MIC2 rather than M2AP directly [#14, #15, #16]\"\n    ]\n  },\n  \"strain_conflicts\": []\n}","audit_flag":null,"strains":[{"strain":"ME49","gene_id":"TGME49_214940","name":"M2AP","product":"MIC2-associated protein M2AP","uniprot_acc":"S8GDJ1","chromosome":"TGME49_chrX","start_pos":6604827},{"strain":"GT1","gene_id":"TGGT1_214940","name":null,"product":"MIC2-associated protein M2AP","uniprot_acc":null,"chromosome":"TGGT1_chrX","start_pos":6494811},{"strain":"RH88","gene_id":"TGRH88_039670","name":null,"product":"MIC2-associated protein M2AP","uniprot_acc":null,"chromosome":"CM023091","start_pos":931270},{"strain":"VEG","gene_id":"TGVEG_214940","name":null,"product":"MIC2-associated protein M2AP","uniprot_acc":"B9QN70","chromosome":"TGVEG_chrX","start_pos":6532620}]}