{"gene":"TG_309600","gene_symbol":"GRA71","run_date":"2026-09-08T18:09:54+00:00","timeline":{"discoveries":[{"year":2023,"finding":"GRA71 forms a heterotrimeric complex with GRA57 and GRA70; these three proteins co-immunoprecipitate with each other and are required for parasite survival in IFNγ-activated human fibroblasts.","method":"Targeted CRISPR screen, gene knockout, co-immunoprecipitation","journal":"PLoS biology","confidence":"High","confidence_rationale":"Tier 2 / Strong — reciprocal co-IP demonstrating complex formation, independent CRISPR screens in two strains, and gene knockout with defined fitness phenotype in human cells; replicated across two independent studies (PMID:37459303 and PMID:36916910)","pmids":["37459303","36916910"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2023,"finding":"GRA71 localizes to dense granules.","method":"Subcellular localization (co-immunoprecipitation context and dense granule marker co-localization implied by GRA32 homology and coimmunoprecipitation with known dense granule proteins)","journal":"mBio","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — localization inferred from co-immunoprecipitation with GRA32 and dense granule proteins, reported in two independent studies but no direct live-imaging or fractionation described in abstracts","pmids":["36916910"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2023,"finding":"Deletion of GRA71 (as part of the GRA57/GRA70/GRA71 complex) leads to reduced ubiquitination of the parasite vacuole by the host cell in IFNγ-stimulated human cells; this is interpreted as a secondary consequence of complex deletion rather than the primary mechanism of IFNγ resistance.","method":"Gene knockout, assessment of host-mediated vacuole ubiquitination","journal":"PLoS biology","confidence":"Medium","confidence_rationale":"Tier 2 / Weak — single lab, clean KO with defined molecular readout (ubiquitination), but mechanistic interpretation is explicitly noted as secondary/indirect by the authors","pmids":["37459303"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2023,"finding":"Deletion of GRA71 (and related complex members with GRA32 homology) causes early parasite egress in IFNγ-stimulated human fibroblasts, indicating the GRA71-containing complex suppresses premature egress.","method":"Gene knockout, parasite egress assay in IFNγ-stimulated primary human fibroblasts","journal":"mBio","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — clean KO with defined cellular phenotype (early egress), confirmed in multiple knockout lines, reported in two independent studies","pmids":["36916910"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":""}]}],"current_model":"GRA71 is a dense granule protein that forms a heterotrimeric complex with GRA57 and GRA70; this complex promotes parasite survival in IFNγ-activated human cells by preventing premature egress, and its deletion secondarily reduces host-mediated ubiquitination of the parasitophorous vacuole."},"narrative":{"mechanistic_narrative":"GRA71 is a Toxoplasma gondii dense granule protein that acts within a host-defense-countering effector module during intracellular infection [PMID:37459303, PMID:36916910]. It assembles into a heterotrimeric complex with GRA57 and GRA70, demonstrated by reciprocal co-immunoprecipitation, and this complex is required for parasite survival in IFNγ-activated human fibroblasts [PMID:37459303, PMID:36916910]. Mechanistically, the GRA71-containing complex suppresses premature parasite egress from IFNγ-stimulated host cells, and its loss triggers early egress [PMID:36916910]. Deletion of GRA71 also reduces host-mediated ubiquitination of the parasitophorous vacuole, a change the authors interpret as a secondary consequence of complex disruption rather than the primary basis of IFNγ resistance [PMID:37459303]. Beyond these findings, the molecular activity of GRA71 and the biochemical basis by which the complex restrains egress have not been characterized in the available corpus.","teleology":[{"year":2023,"claim":"Whether GRA71 functions alone or as part of an effector assembly was unknown; establishing its complex membership defined the functional unit relevant to IFNγ resistance.","evidence":"Targeted CRISPR screen, gene knockout, and reciprocal co-immunoprecipitation in Toxoplasma gondii, replicated across two independent studies","pmids":["37459303","36916910"],"confidence":"High","gaps":["Stoichiometry and structural organization of the GRA57/GRA70/GRA71 complex are not resolved","The direct host or parasite molecular targets of the complex are not identified"],"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2023,"claim":"The subcellular compartment from which GRA71 acts was unclear; assigning it to dense granules placed it among secreted vacuole-modifying effectors.","evidence":"Localization inferred from co-immunoprecipitation with GRA32 and known dense granule proteins in Toxoplasma gondii","pmids":["36916910"],"confidence":"Medium","gaps":["Localization inferred from co-IP context rather than direct live-imaging or fractionation","Whether GRA71 is trafficked to the vacuole membrane or lumen is not established"],"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2023,"claim":"The cellular phenotype underlying GRA71-dependent survival was unknown; showing that deletion causes early egress established that the complex suppresses premature exit under IFNγ pressure.","evidence":"Gene knockout and parasite egress assay in IFNγ-stimulated primary human fibroblasts, confirmed in multiple knockout lines across two studies","pmids":["36916910"],"confidence":"Medium","gaps":["The molecular signal linking complex loss to premature egress is unknown","Whether egress suppression is direct or downstream of vacuole integrity is unresolved"],"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2023,"claim":"How GRA71 loss alters the host response was tested; reduced vacuole ubiquitination was found but interpreted as a secondary consequence rather than the causal mechanism of IFNγ resistance.","evidence":"Gene knockout with assessment of host-mediated vacuole ubiquitination in IFNγ-stimulated human cells","pmids":["37459303"],"confidence":"Medium","gaps":["Causal relationship between ubiquitination change and survival is not established; authors flag it as secondary","The host ubiquitin machinery involved is not identified"],"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":null,"claim":"The molecular activity of GRA71 and the mechanism by which the GRA57/GRA70/GRA71 complex restrains egress and modulates host defense remain undefined.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No enzymatic or biochemical activity assigned to GRA71","No direct interacting host factors identified","No structural model of the heterotrimeric complex"],"attribution":[{"species":"Toxoplasma gondii","strain":""}]}],"mechanism_profile":{"molecular_activity":[],"localization":[],"pathway":[],"complexes":["GRA57/GRA70/GRA71 heterotrimeric dense granule complex"],"partners":["GRA57","GRA70","GRA32"],"other_free_text":["Required for parasite survival in IFNγ-activated human fibroblasts [#0]","Suppresses premature parasite egress under IFNγ stimulation [#3]","Deletion reduces host-mediated ubiquitination of the parasitophorous vacuole, interpreted as a secondary effect [#2]"]},"strain_conflicts":[]},"prefetch_data":{},"corpus_meta":[{"pmid":"36916910","id":"PMC_36916910","title":"CRISPR Screens Identify Toxoplasma Genes That Determine Parasite Fitness in Interferon Gamma-Stimulated Human Cells.","date":"2023","source":"mBio","url":"https://pubmed.ncbi.nlm.nih.gov/36916910","citation_count":29,"is_preprint":false},{"pmid":"37459303","id":"PMC_37459303","title":"A heterotrimeric complex of Toxoplasma proteins promotes parasite survival in interferon gamma-stimulated human cells.","date":"2023","source":"PLoS biology","url":"https://pubmed.ncbi.nlm.nih.gov/37459303","citation_count":24,"is_preprint":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":3545,"output_tokens":1024,"usd":0.012998,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":5923,"output_tokens":2063,"usd":0.040595,"stage2_stop_reason":"end_turn"},"total_usd":0.0,"stage1_batch_id":"msgbatch_01XFXJD6iZecXyWn9uU5Qom9","stage2_batch_id":"msgbatch_013GToKgs4AKSCRE4yvueviH","note":"batch pricing = 50% of standard","skipped":true},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2023,\n      \"finding\": \"GRA71 forms a heterotrimeric complex with GRA57 and GRA70; these three proteins co-immunoprecipitate with each other and are required for parasite survival in IFNγ-activated human fibroblasts.\",\n      \"method\": \"Targeted CRISPR screen, gene knockout, co-immunoprecipitation\",\n      \"journal\": \"PLoS biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — reciprocal co-IP demonstrating complex formation, independent CRISPR screens in two strains, and gene knockout with defined fitness phenotype in human cells; replicated across two independent studies (PMID:37459303 and PMID:36916910)\",\n      \"pmids\": [\"37459303\", \"36916910\"],\n      \"is_preprint\": false,\n      \"attribution\": [\n        {\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}\n      ]\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"GRA71 localizes to dense granules.\",\n      \"method\": \"Subcellular localization (co-immunoprecipitation context and dense granule marker co-localization implied by GRA32 homology and coimmunoprecipitation with known dense granule proteins)\",\n      \"journal\": \"mBio\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — localization inferred from co-immunoprecipitation with GRA32 and dense granule proteins, reported in two independent studies but no direct live-imaging or fractionation described in abstracts\",\n      \"pmids\": [\"36916910\"],\n      \"is_preprint\": false,\n      \"attribution\": [\n        {\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}\n      ]\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"Deletion of GRA71 (as part of the GRA57/GRA70/GRA71 complex) leads to reduced ubiquitination of the parasite vacuole by the host cell in IFNγ-stimulated human cells; this is interpreted as a secondary consequence of complex deletion rather than the primary mechanism of IFNγ resistance.\",\n      \"method\": \"Gene knockout, assessment of host-mediated vacuole ubiquitination\",\n      \"journal\": \"PLoS biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Weak — single lab, clean KO with defined molecular readout (ubiquitination), but mechanistic interpretation is explicitly noted as secondary/indirect by the authors\",\n      \"pmids\": [\"37459303\"],\n      \"is_preprint\": false,\n      \"attribution\": [\n        {\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}\n      ]\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"Deletion of GRA71 (and related complex members with GRA32 homology) causes early parasite egress in IFNγ-stimulated human fibroblasts, indicating the GRA71-containing complex suppresses premature egress.\",\n      \"method\": \"Gene knockout, parasite egress assay in IFNγ-stimulated primary human fibroblasts\",\n      \"journal\": \"mBio\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — clean KO with defined cellular phenotype (early egress), confirmed in multiple knockout lines, reported in two independent studies\",\n      \"pmids\": [\"36916910\"],\n      \"is_preprint\": false,\n      \"attribution\": [\n        {\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}\n      ]\n    }\n  ],\n  \"current_model\": \"GRA71 is a dense granule protein that forms a heterotrimeric complex with GRA57 and GRA70; this complex promotes parasite survival in IFNγ-activated human cells by preventing premature egress, and its deletion secondarily reduces host-mediated ubiquitination of the parasitophorous vacuole.\"\n}\n```","stage2_raw":"```json\n{\n  \"mechanistic_narrative\": \"GRA71 is a Toxoplasma gondii dense granule protein that acts within a host-defense-countering effector module during intracellular infection [#0, #1]. It assembles into a heterotrimeric complex with GRA57 and GRA70, demonstrated by reciprocal co-immunoprecipitation, and this complex is required for parasite survival in IFN\\u03b3-activated human fibroblasts [#0]. Mechanistically, the GRA71-containing complex suppresses premature parasite egress from IFN\\u03b3-stimulated host cells, and its loss triggers early egress [#3]. Deletion of GRA71 also reduces host-mediated ubiquitination of the parasitophorous vacuole, a change the authors interpret as a secondary consequence of complex disruption rather than the primary basis of IFN\\u03b3 resistance [#2]. Beyond these findings, the molecular activity of GRA71 and the biochemical basis by which the complex restrains egress have not been characterized in the available corpus.\",\n  \"teleology\": [\n    {\n      \"year\": 2023,\n      \"claim\": \"Whether GRA71 functions alone or as part of an effector assembly was unknown; establishing its complex membership defined the functional unit relevant to IFN\\u03b3 resistance.\",\n      \"evidence\": \"Targeted CRISPR screen, gene knockout, and reciprocal co-immunoprecipitation in Toxoplasma gondii, replicated across two independent studies\",\n      \"pmids\": [\"37459303\", \"36916910\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Stoichiometry and structural organization of the GRA57/GRA70/GRA71 complex are not resolved\",\n        \"The direct host or parasite molecular targets of the complex are not identified\"\n      ],\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"The subcellular compartment from which GRA71 acts was unclear; assigning it to dense granules placed it among secreted vacuole-modifying effectors.\",\n      \"evidence\": \"Localization inferred from co-immunoprecipitation with GRA32 and known dense granule proteins in Toxoplasma gondii\",\n      \"pmids\": [\"36916910\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"Localization inferred from co-IP context rather than direct live-imaging or fractionation\",\n        \"Whether GRA71 is trafficked to the vacuole membrane or lumen is not established\"\n      ],\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"The cellular phenotype underlying GRA71-dependent survival was unknown; showing that deletion causes early egress established that the complex suppresses premature exit under IFN\\u03b3 pressure.\",\n      \"evidence\": \"Gene knockout and parasite egress assay in IFN\\u03b3-stimulated primary human fibroblasts, confirmed in multiple knockout lines across two studies\",\n      \"pmids\": [\"36916910\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"The molecular signal linking complex loss to premature egress is unknown\",\n        \"Whether egress suppression is direct or downstream of vacuole integrity is unresolved\"\n      ],\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"How GRA71 loss alters the host response was tested; reduced vacuole ubiquitination was found but interpreted as a secondary consequence rather than the causal mechanism of IFN\\u03b3 resistance.\",\n      \"evidence\": \"Gene knockout with assessment of host-mediated vacuole ubiquitination in IFN\\u03b3-stimulated human cells\",\n      \"pmids\": [\"37459303\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"Causal relationship between ubiquitination change and survival is not established; authors flag it as secondary\",\n        \"The host ubiquitin machinery involved is not identified\"\n      ],\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"The molecular activity of GRA71 and the mechanism by which the GRA57/GRA70/GRA71 complex restrains egress and modulates host defense remain undefined.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"No enzymatic or biochemical activity assigned to GRA71\",\n        \"No direct interacting host factors identified\",\n        \"No structural model of the heterotrimeric complex\"\n      ],\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [],\n    \"localization\": [\n      {\"term_id\": \"GO:0020003\", \"supporting_discovery_ids\": [1], \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"GO:0052167\", \"supporting_discovery_ids\": [0, 2, 3], \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]}\n    ],\n    \"complexes\": [\"GRA57/GRA70/GRA71 heterotrimeric dense granule complex\"],\n    \"partners\": [\"GRA57\", \"GRA70\", \"GRA32\"],\n    \"other_free_text\": [\n      \"Required for parasite survival in IFN\\u03b3-activated human fibroblasts [#0]\",\n      \"Suppresses premature parasite egress under IFN\\u03b3 stimulation [#3]\",\n      \"Deletion reduces host-mediated ubiquitination of the parasitophorous vacuole, interpreted as a secondary effect [#2]\"\n    ]\n  },\n  \"strain_conflicts\": []\n}\n```","audit_flag":null,"strains":[{"strain":"ME49","gene_id":"TGME49_309600","name":"GRA71","product":"dense granule protein GRA71","uniprot_acc":"A0A125YR84","chromosome":"TGME49_chrXI","start_pos":750828},{"strain":"GT1","gene_id":"TGGT1_309600","name":null,"product":"hypothetical protein","uniprot_acc":null,"chromosome":"TGGT1_chrXI","start_pos":713110},{"strain":"RH88","gene_id":"TGRH88_049180","name":null,"product":"unspecified product","uniprot_acc":null,"chromosome":"CM023092","start_pos":798971},{"strain":"VEG","gene_id":"TGVEG_309600","name":null,"product":"hypothetical protein","uniprot_acc":"B6KA39","chromosome":"TGVEG_chrXI","start_pos":759894}]}