{"gene":"TG_278975","gene_symbol":"MCA2","run_date":"2026-09-08T14:08:30","timeline":{"discoveries":[{"year":2021,"finding":"MCA2 (together with MCA1) localizes to the cytoplasm with punctuated aggregation, and part of this aggregation is found on the inner membrane complex (IMC) of T. gondii, as determined by fluorescence localization experiments.","method":"Subcellular localization by fluorescence microscopy of transgenic strains","journal":"Parasites & vectors","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — direct localization experiment in transgenic parasites, single lab, reported for both MCA1 and MCA2 together","pmids":["34384491"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":"RHΔku80"}]},{"year":2021,"finding":"MCA1/MCA2 double knockout (but not either single knockout alone) causes reduced parasite proliferation and impaired endodyogeny, manifested as multiple nuclei and abnormal IMC1 expression in tachyzoites.","method":"Genetic knockout (MCA1/MCA2 double KO) with growth assays and microscopic analysis of nuclear content and IMC1 expression","journal":"Parasites & vectors","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — clean double KO with defined cellular phenotype, single lab, multiple readouts (growth, nuclear morphology, IMC1 expression)","pmids":["34384491"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":"RHΔku80"}]},{"year":2021,"finding":"MCA1 and MCA2 are required for IMC1 maturation: in the MCA1/MCA2 double-knockout strain, IMC1 becomes detergent-soluble (indicative of failure to form insoluble mature IMC1 polymer), establishing a functional link between these metacaspases and IMC1 processing/maturation.","method":"Detergent solubility assay of IMC1 in double-knockout parasites","journal":"Parasites & vectors","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — biochemical fractionation (detergent solubility) combined with KO, single lab","pmids":["34384491"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":"RHΔku80"}]},{"year":2021,"finding":"The MCA1/MCA2 double-knockout strain is more readily converted from tachyzoites to bradyzoites in vitro and is less virulent in mice, forming cysts in the brain and establishing chronic infection, indicating a combined role for MCA1 and MCA2 in stage conversion and pathogenesis.","method":"In vitro differentiation assay and mouse infection model with double-knockout strain","journal":"Parasites & vectors","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — KO with defined in vivo and in vitro phenotypic readouts, single lab","pmids":["34384491"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":"RHΔku80"}]},{"year":2020,"finding":"TgMCA2 knockout in the Pru strain results in increased proliferative capacity, while invasion and egress are unaffected, indicating MCA2 normally restrains tachyzoite proliferation but is not required for host cell invasion or egress.","method":"Gene knockout with proliferation, invasion, and egress assays","journal":"Parasitology research","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — clean KO with multiple defined functional readouts, single lab","pmids":["32468190"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":"Pru"}]},{"year":2020,"finding":"TgMCA2 is required for tachyzoite-to-bradyzoite differentiation in the Pru strain: Δmca2 tachyzoites fail to form bradyzoites in vitro, show significantly reduced transcription of bradyzoite-specific genes (BAG1, LDH2, SAG4A), and form no cysts in vivo, establishing MCA2 as a positive regulator of stage conversion.","method":"Gene knockout with in vitro differentiation assay, qRT-PCR of stage-specific genes, and mouse infection model (cyst detection)","journal":"Parasitology research","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — KO with multiple orthogonal readouts (morphology, gene expression, in vivo cysts), single lab","pmids":["32468190"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":"Pru"}]}],"current_model":"TgMCA2 is a cytoplasmic metacaspase (with partial IMC localization) that, redundantly with MCA1, promotes IMC1 maturation and endodyogeny in tachyzoites; it also acts as a positive regulator of tachyzoite-to-bradyzoite stage conversion by supporting expression of bradyzoite-specific genes, while its loss paradoxically increases tachyzoite proliferation without affecting invasion or egress."},"narrative":{"mechanistic_narrative":"TgMCA2 is a metacaspase of Toxoplasma gondii that, together with MCA1, contributes to daughter-cell formation during endodyogeny and to the regulation of tachyzoite-to-bradyzoite stage conversion [PMID:34384491, PMID:32468190]. The protein localizes predominantly to the cytoplasm as punctate aggregates, a portion of which associate with the inner membrane complex (IMC) [PMID:34384491]. MCA2 acts redundantly with MCA1 in cytokinesis: only the MCA1/MCA2 double knockout, not either single knockout, impairs proliferation and endodyogeny, producing multinucleate parasites with aberrant IMC1 expression, and abolishes formation of the detergent-insoluble mature IMC1 polymer — linking these metacaspases to IMC1 maturation [PMID:34384491]. MCA2 is also a positive regulator of differentiation: in the Pru strain, Δmca2 tachyzoites fail to form bradyzoites in vitro, show reduced transcription of the bradyzoite genes BAG1, LDH2 and SAG4A, and form no brain cysts in vivo, yet display increased proliferative capacity with normal invasion and egress [PMID:32468190]. Consistently, MCA1/MCA2 double-knockout parasites are less virulent, convert more readily to bradyzoites, and establish chronic brain-cyst infection [PMID:34384491]. The protease substrates and catalytic mechanism underlying these roles have not been characterized in the available corpus.","teleology":[{"year":2020,"claim":"Establishing whether MCA2 has a non-redundant role revealed that it restrains tachyzoite proliferation while being dispensable for invasion and egress, distinguishing its function from the host-cell entry/exit machinery.","evidence":"Single-gene knockout in the Pru strain with proliferation, invasion, and egress assays","pmids":["32468190"],"confidence":"Medium","gaps":["Mechanism by which MCA2 restrains proliferation not defined","No protease substrate identified","Catalytic requirement not tested"],"attribution":[{"species":"Toxoplasma gondii","strain":"Pru"}]},{"year":2020,"claim":"Testing MCA2's role in differentiation established it as a positive regulator of tachyzoite-to-bradyzoite conversion, connecting a metacaspase to stage-specific gene expression and cyst formation.","evidence":"Δmca2 knockout with in vitro differentiation, qRT-PCR of BAG1/LDH2/SAG4A, and mouse cyst-detection assays in the Pru strain","pmids":["32468190"],"confidence":"Medium","gaps":["How MCA2 promotes bradyzoite gene transcription is unknown","Direct targets in the differentiation pathway not identified","Whether protease activity is required for this role untested"],"attribution":[{"species":"Toxoplasma gondii","strain":"Pru"}]},{"year":2021,"claim":"Mapping subcellular localization placed MCA1/MCA2 in the cytoplasm with partial IMC association, providing a spatial rationale for their involvement in IMC-related processes.","evidence":"Fluorescence microscopy of transgenic RHΔku80 parasites","pmids":["34384491"],"confidence":"Medium","gaps":["Nature of the IMC association (direct vs. indirect) unresolved","MCA1 and MCA2 localizations reported together, not individually resolved"],"attribution":[{"species":"Toxoplasma gondii","strain":"RHΔku80"}]},{"year":2021,"claim":"Combining double knockout with morphology and biochemistry showed MCA1 and MCA2 act redundantly in endodyogeny and are required for IMC1 maturation, defining a molecular readout (loss of the insoluble IMC1 polymer) for their function.","evidence":"MCA1/MCA2 double knockout with growth assays, nuclear-content microscopy, IMC1 expression analysis, and IMC1 detergent-solubility fractionation in RHΔku80","pmids":["34384491"],"confidence":"Medium","gaps":["Whether MCA2 directly processes IMC1 not shown","Redundancy mechanism between MCA1 and MCA2 undefined","No catalytic-dead complementation to test protease dependence"],"attribution":[{"species":"Toxoplasma gondii","strain":"RHΔku80"}]},{"year":2021,"claim":"In vivo and in vitro assessment of the double knockout linked MCA1/MCA2 loss to enhanced bradyzoite conversion, reduced virulence, and chronic cyst formation, tying their cytokinesis role to pathogenesis outcomes.","evidence":"In vitro differentiation assay and mouse infection model with RHΔku80 double-knockout strain","pmids":["34384491"],"confidence":"Medium","gaps":["Direction of the conversion phenotype differs from single Δmca2 in Pru","Causal chain from IMC/endodyogeny defect to differentiation not established"],"attribution":[{"species":"Toxoplasma gondii","strain":"RHΔku80"}]},{"year":null,"claim":"The catalytic mechanism, direct proteolytic substrates, and the basis for redundancy with MCA1 remain unresolved.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No identified protease substrate for MCA2","No test of whether catalytic activity underlies proliferation, IMC1 maturation, or differentiation roles","No structural characterization"],"attribution":[]}],"mechanism_profile":{"molecular_activity":[],"localization":[],"pathway":[],"complexes":[],"partners":["MCA1 (FUNCTIONALLY REDUNDANT METACASPASE)","IMC1 (MATURATION SUBSTRATE/TARGET)"],"other_free_text":["MCA2 restrains tachyzoite proliferation; its loss increases proliferative capacity without affecting invasion or egress [#4]","MCA2 supports transcription of bradyzoite-specific genes BAG1, LDH2, and SAG4A and is required for cyst formation in vivo [#5]","MCA1/MCA2 loss reduces virulence and favors chronic brain-cyst infection in mice [#3]"]},"strain_conflicts":[{"aspect":"Effect of MCA2 loss on tachyzoite-to-bradyzoite conversion","claims":[{"attribution":[{"species":"Toxoplasma gondii","strain":"Pru"}],"claim":"Single Δmca2 fails to form bradyzoites in vitro and forms no cysts in vivo, with reduced bradyzoite-gene transcription, indicating MCA2 positively promotes conversion","supporting_discovery_ids":[5]},{"attribution":[{"species":"Toxoplasma gondii","strain":"RHΔku80"}],"claim":"MCA1/MCA2 double knockout converts more readily to bradyzoites and establishes chronic cyst infection","supporting_discovery_ids":[3]}]}]},"prefetch_data":{},"corpus_meta":[{"pmid":"34384491","id":"PMC_34384491","title":"Requirement of Toxoplasma gondii metacaspases for IMC1 maturation, endodyogeny and virulence in mice.","date":"2021","source":"Parasites & vectors","url":"https://pubmed.ncbi.nlm.nih.gov/34384491","citation_count":5,"is_preprint":false},{"pmid":"32468190","id":"PMC_32468190","title":"Toxoplasma gondii metacaspase 2 is an important factor that influences bradyzoite formation in the Pru strain.","date":"2020","source":"Parasitology research","url":"https://pubmed.ncbi.nlm.nih.gov/32468190","citation_count":3,"is_preprint":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":3643,"output_tokens":1518,"usd":0.016849,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":6647,"output_tokens":3084,"usd":0.055168,"stage2_stop_reason":"end_turn"},"total_usd":0.072017,"stage1_batch_id":"msgbatch_015xmQKDRqnTh9anE4m7LiD6","stage2_batch_id":"msgbatch_01JLpkFTVhoQBNgqHCKFrVVU","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2021,\n      \"finding\": \"MCA2 (together with MCA1) localizes to the cytoplasm with punctuated aggregation, and part of this aggregation is found on the inner membrane complex (IMC) of T. gondii, as determined by fluorescence localization experiments.\",\n      \"method\": \"Subcellular localization by fluorescence microscopy of transgenic strains\",\n      \"journal\": \"Parasites & vectors\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — direct localization experiment in transgenic parasites, single lab, reported for both MCA1 and MCA2 together\",\n      \"pmids\": [\"34384491\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"RHΔku80\"}]\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"MCA1/MCA2 double knockout (but not either single knockout alone) causes reduced parasite proliferation and impaired endodyogeny, manifested as multiple nuclei and abnormal IMC1 expression in tachyzoites.\",\n      \"method\": \"Genetic knockout (MCA1/MCA2 double KO) with growth assays and microscopic analysis of nuclear content and IMC1 expression\",\n      \"journal\": \"Parasites & vectors\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — clean double KO with defined cellular phenotype, single lab, multiple readouts (growth, nuclear morphology, IMC1 expression)\",\n      \"pmids\": [\"34384491\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"RHΔku80\"}]\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"MCA1 and MCA2 are required for IMC1 maturation: in the MCA1/MCA2 double-knockout strain, IMC1 becomes detergent-soluble (indicative of failure to form insoluble mature IMC1 polymer), establishing a functional link between these metacaspases and IMC1 processing/maturation.\",\n      \"method\": \"Detergent solubility assay of IMC1 in double-knockout parasites\",\n      \"journal\": \"Parasites & vectors\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — biochemical fractionation (detergent solubility) combined with KO, single lab\",\n      \"pmids\": [\"34384491\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"RHΔku80\"}]\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"The MCA1/MCA2 double-knockout strain is more readily converted from tachyzoites to bradyzoites in vitro and is less virulent in mice, forming cysts in the brain and establishing chronic infection, indicating a combined role for MCA1 and MCA2 in stage conversion and pathogenesis.\",\n      \"method\": \"In vitro differentiation assay and mouse infection model with double-knockout strain\",\n      \"journal\": \"Parasites & vectors\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — KO with defined in vivo and in vitro phenotypic readouts, single lab\",\n      \"pmids\": [\"34384491\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"RHΔku80\"}]\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"TgMCA2 knockout in the Pru strain results in increased proliferative capacity, while invasion and egress are unaffected, indicating MCA2 normally restrains tachyzoite proliferation but is not required for host cell invasion or egress.\",\n      \"method\": \"Gene knockout with proliferation, invasion, and egress assays\",\n      \"journal\": \"Parasitology research\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — clean KO with multiple defined functional readouts, single lab\",\n      \"pmids\": [\"32468190\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"Pru\"}]\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"TgMCA2 is required for tachyzoite-to-bradyzoite differentiation in the Pru strain: Δmca2 tachyzoites fail to form bradyzoites in vitro, show significantly reduced transcription of bradyzoite-specific genes (BAG1, LDH2, SAG4A), and form no cysts in vivo, establishing MCA2 as a positive regulator of stage conversion.\",\n      \"method\": \"Gene knockout with in vitro differentiation assay, qRT-PCR of stage-specific genes, and mouse infection model (cyst detection)\",\n      \"journal\": \"Parasitology research\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — KO with multiple orthogonal readouts (morphology, gene expression, in vivo cysts), single lab\",\n      \"pmids\": [\"32468190\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"Pru\"}]\n    }\n  ],\n  \"current_model\": \"TgMCA2 is a cytoplasmic metacaspase (with partial IMC localization) that, redundantly with MCA1, promotes IMC1 maturation and endodyogeny in tachyzoites; it also acts as a positive regulator of tachyzoite-to-bradyzoite stage conversion by supporting expression of bradyzoite-specific genes, while its loss paradoxically increases tachyzoite proliferation without affecting invasion or egress.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"TgMCA2 is a metacaspase of Toxoplasma gondii that, together with MCA1, contributes to daughter-cell formation during endodyogeny and to the regulation of tachyzoite-to-bradyzoite stage conversion [#1, #5]. The protein localizes predominantly to the cytoplasm as punctate aggregates, a portion of which associate with the inner membrane complex (IMC) [#0]. MCA2 acts redundantly with MCA1 in cytokinesis: only the MCA1/MCA2 double knockout, not either single knockout, impairs proliferation and endodyogeny, producing multinucleate parasites with aberrant IMC1 expression, and abolishes formation of the detergent-insoluble mature IMC1 polymer — linking these metacaspases to IMC1 maturation [#1, #2]. MCA2 is also a positive regulator of differentiation: in the Pru strain, \\u0394mca2 tachyzoites fail to form bradyzoites in vitro, show reduced transcription of the bradyzoite genes BAG1, LDH2 and SAG4A, and form no brain cysts in vivo, yet display increased proliferative capacity with normal invasion and egress [#4, #5]. Consistently, MCA1/MCA2 double-knockout parasites are less virulent, convert more readily to bradyzoites, and establish chronic brain-cyst infection [#3]. The protease substrates and catalytic mechanism underlying these roles have not been characterized in the available corpus.\",\n  \"teleology\": [\n    {\n      \"year\": 2020,\n      \"claim\": \"Establishing whether MCA2 has a non-redundant role revealed that it restrains tachyzoite proliferation while being dispensable for invasion and egress, distinguishing its function from the host-cell entry/exit machinery.\",\n      \"evidence\": \"Single-gene knockout in the Pru strain with proliferation, invasion, and egress assays\",\n      \"pmids\": [\"32468190\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Mechanism by which MCA2 restrains proliferation not defined\", \"No protease substrate identified\", \"Catalytic requirement not tested\"],\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"Pru\"}]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"Testing MCA2's role in differentiation established it as a positive regulator of tachyzoite-to-bradyzoite conversion, connecting a metacaspase to stage-specific gene expression and cyst formation.\",\n      \"evidence\": \"\\u0394mca2 knockout with in vitro differentiation, qRT-PCR of BAG1/LDH2/SAG4A, and mouse cyst-detection assays in the Pru strain\",\n      \"pmids\": [\"32468190\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"How MCA2 promotes bradyzoite gene transcription is unknown\", \"Direct targets in the differentiation pathway not identified\", \"Whether protease activity is required for this role untested\"],\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"Pru\"}]\n    },\n    {\n      \"year\": 2021,\n      \"claim\": \"Mapping subcellular localization placed MCA1/MCA2 in the cytoplasm with partial IMC association, providing a spatial rationale for their involvement in IMC-related processes.\",\n      \"evidence\": \"Fluorescence microscopy of transgenic RH\\u0394ku80 parasites\",\n      \"pmids\": [\"34384491\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Nature of the IMC association (direct vs. indirect) unresolved\", \"MCA1 and MCA2 localizations reported together, not individually resolved\"],\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"RH\\u0394ku80\"}]\n    },\n    {\n      \"year\": 2021,\n      \"claim\": \"Combining double knockout with morphology and biochemistry showed MCA1 and MCA2 act redundantly in endodyogeny and are required for IMC1 maturation, defining a molecular readout (loss of the insoluble IMC1 polymer) for their function.\",\n      \"evidence\": \"MCA1/MCA2 double knockout with growth assays, nuclear-content microscopy, IMC1 expression analysis, and IMC1 detergent-solubility fractionation in RH\\u0394ku80\",\n      \"pmids\": [\"34384491\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Whether MCA2 directly processes IMC1 not shown\", \"Redundancy mechanism between MCA1 and MCA2 undefined\", \"No catalytic-dead complementation to test protease dependence\"],\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"RH\\u0394ku80\"}]\n    },\n    {\n      \"year\": 2021,\n      \"claim\": \"In vivo and in vitro assessment of the double knockout linked MCA1/MCA2 loss to enhanced bradyzoite conversion, reduced virulence, and chronic cyst formation, tying their cytokinesis role to pathogenesis outcomes.\",\n      \"evidence\": \"In vitro differentiation assay and mouse infection model with RH\\u0394ku80 double-knockout strain\",\n      \"pmids\": [\"34384491\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direction of the conversion phenotype differs from single \\u0394mca2 in Pru\", \"Causal chain from IMC/endodyogeny defect to differentiation not established\"],\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"RH\\u0394ku80\"}]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"The catalytic mechanism, direct proteolytic substrates, and the basis for redundancy with MCA1 remain unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No identified protease substrate for MCA2\", \"No test of whether catalytic activity underlies proliferation, IMC1 maturation, or differentiation roles\", \"No structural characterization\"],\n      \"attribution\": []\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0004197\", \"supporting_discovery_ids\": [2], \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"RH\\u0394ku80\"}]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005737\", \"supporting_discovery_ids\": [0], \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"RH\\u0394ku80\"}]},\n      {\"term_id\": \"GO:0070258\", \"supporting_discovery_ids\": [0], \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"RH\\u0394ku80\"}]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"GO:0000281\", \"supporting_discovery_ids\": [1, 2], \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"RH\\u0394ku80\"}]},\n      {\"term_id\": \"GO:0030154\", \"supporting_discovery_ids\": [3, 5], \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"RH\\u0394ku80\"}, {\"species\": \"Toxoplasma gondii\", \"strain\": \"Pru\"}]}\n    ],\n    \"complexes\": [],\n    \"partners\": [\"MCA1 (functionally redundant metacaspase)\", \"IMC1 (maturation substrate/target)\"],\n    \"other_free_text\": [\n      \"MCA2 restrains tachyzoite proliferation; its loss increases proliferative capacity without affecting invasion or egress [#4]\",\n      \"MCA2 supports transcription of bradyzoite-specific genes BAG1, LDH2, and SAG4A and is required for cyst formation in vivo [#5]\",\n      \"MCA1/MCA2 loss reduces virulence and favors chronic brain-cyst infection in mice [#3]\"\n    ]\n  },\n  \"strain_conflicts\": [\n    {\n      \"aspect\": \"Effect of MCA2 loss on tachyzoite-to-bradyzoite conversion\",\n      \"claims\": [\n        {\"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"Pru\"}], \"claim\": \"Single \\u0394mca2 fails to form bradyzoites in vitro and forms no cysts in vivo, with reduced bradyzoite-gene transcription, indicating MCA2 positively promotes conversion\", \"supporting_discovery_ids\": [5]},\n        {\"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"RH\\u0394ku80\"}], \"claim\": \"MCA1/MCA2 double knockout converts more readily to bradyzoites and establishes chronic cyst infection\", \"supporting_discovery_ids\": [3]}\n      ]\n    }\n  ]\n}","audit_flag":null,"strains":[{"strain":"ME49","gene_id":"TGME49_278975","name":"MCA2","product":"metacaspase MCA2","uniprot_acc":"S8ESH8","chromosome":"TGME49_chrXII","start_pos":5711668},{"strain":"GT1","gene_id":"TGGT1_278975","name":null,"product":"ICE family protease (caspase) p20 domain-containing protein","uniprot_acc":null,"chromosome":"TGGT1_chrXII","start_pos":5626974},{"strain":"RH88","gene_id":"TGRH88_064890","name":null,"product":"ICE family protease (caspase) p20 domain-containing protein","uniprot_acc":null,"chromosome":"CM023093","start_pos":5795117},{"strain":"VEG","gene_id":"TGVEG_278975","name":null,"product":"ICE family protease (caspase) p20 domain-containing protein","uniprot_acc":"A0A125YJJ6","chromosome":"TGVEG_chrXII","start_pos":5717102}]}