{"gene":"TG_272460","gene_symbol":"GRA72","run_date":"2026-09-08T14:08:30","timeline":{"discoveries":[{"year":2024,"finding":"GRA72 is a dense granule protein that localizes to the parasitophorous vacuole membrane (PVM) and parasitophorous vacuole (PV), and deletion of GRA72 produces an aberrant 'bubble vacuole' morphology with reduced small molecule permeability across the PVM, similar to deletion of GRA17.","method":"Gene knockout (Δgra72) with vacuole morphology imaging and small molecule permeability assays","journal":"mBio","confidence":"High","confidence_rationale":"Tier 2 / Strong — loss-of-function genetic deletion with defined cellular phenotype (aberrant PV morphology, reduced PVM permeability), replicated across two independent labs (PMID:38380952, PMID:38936501)","pmids":["38380952","38936501"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2024,"finding":"GRA72 physically interacts with GRA47, as determined by immunoprecipitation; GRA47 is identified as a binding partner of GRA72 at the PVM.","method":"Immunoprecipitation (Co-IP) / pulldown","journal":"mBio","confidence":"High","confidence_rationale":"Tier 2 / Strong — reciprocal Co-IP confirmed in two independent studies (PMID:38380952, PMID:38936501)","pmids":["38380952","38936501"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2024,"finding":"Structural predictions indicate GRA72 forms a hexameric pore with conserved histidine residues lining the pore; mutational analysis of these histidines demonstrated they are critical for GRA72 functionality, and electrophysiology confirmed alterations in membrane conductance consistent with pore-forming activity.","method":"Computational structural prediction, site-directed mutagenesis of histidine residues, electrophysiology","journal":"mBio","confidence":"High","confidence_rationale":"Tier 1 / Moderate — structural prediction combined with mutagenesis and electrophysiological validation in a single rigorous study, single lab","pmids":["38380952"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2023,"finding":"GRA72 was identified as synthetically lethal with GRA17 in an in vivo CRISPR screen, and screen results suggest GRA72 plays a role in normal GRA17/GRA23 localization at the PVM.","method":"In vivo CRISPR screen in mice (C57BL/6 and Ifngr1−/− hosts)","journal":"Cell reports","confidence":"Medium","confidence_rationale":"Tier 2 / Weak — in vivo CRISPR screen with genetic epistasis evidence, but the role in GRA17/GRA23 localization is a screen-level inference from a single study without direct localization experiments shown for GRA72","pmids":["37269286"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2024,"finding":"Deletion of GRA72 in the Pru strain (PruΔgra72) results in attenuated virulence in mice, with significantly decreased parasite load in organs and reduced brain cyst burden, establishing GRA72 as a virulence factor required for normal in vivo growth.","method":"Gene knockout (PruΔgra72) with in vivo mouse infection assays measuring survival, organ parasite load, and brain cyst burden","journal":"Parasites & vectors","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — clean KO with defined in vivo phenotype, single lab, replicated across multiple mouse experiments","pmids":["39237959"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":"Pru"}]},{"year":2024,"finding":"In the Δgra23Δgra72 double knockout strain, the proportion of aberrant PVs was significantly increased compared to Δgra23 alone, indicating GRA72 and GRA23 function in partially non-redundant pathways to maintain PV morphology. Overexpression of GRA17, GRA47, or GRA72 individually only partially rescued aberrant PV morphology in Δgra47, Δgra72, or Δgra17, while the Plasmodium falciparum PVM protein PfExp2 (ortholog of GRA17/GRA23) fully rescued all three single knockouts.","method":"Double gene deletion, overexpression rescue experiments, morphology quantification","journal":"International journal for parasitology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — genetic epistasis via double KO and rescue experiments, single lab, multiple orthogonal approaches","pmids":["38936501"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2026,"finding":"Transcriptomic analysis (RNA-seq) of PruΔgra72 compared to wild-type Pru revealed 858 differentially expressed genes, with upregulation of bradyzoite-associated genes and bidirectional regulation of dense granule proteins (GRAs); DEGs were enriched in membrane-related functional categories and key metabolic pathways (fatty acid, carbon, and amino acid metabolism), implicating GRA72 in membrane-associated functions and metabolic homeostasis.","method":"RNA-seq transcriptomic analysis of knockout strain vs. wild-type, validated by RT-qPCR","journal":"Acta parasitologica","confidence":"Low","confidence_rationale":"Tier 4 / Weak — transcriptomic/expression-based analysis; no direct mechanistic experiments linking GRA72 protein to specific metabolic or membrane pathways, single lab","pmids":["42068418"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":"Pru"}]}],"current_model":"GRA72 is a dense granule protein that localizes to the parasitophorous vacuole membrane (PVM) and forms a hexameric pore (with critical histidine residues lining the channel) that regulates small molecule permeability across the PVM; it physically interacts with GRA47, acts in a partially non-redundant pathway alongside GRA17 and GRA23 to maintain PV morphology and nutrient flux, is synthetically lethal with GRA17, and is required for normal in vivo virulence in Toxoplasma gondii."},"narrative":{"mechanistic_narrative":"GRA72 is a Toxoplasma gondii dense granule protein that governs small-molecule permeability across the parasitophorous vacuole membrane (PVM), where it localizes together with the PV [PMID:38380952, PMID:38936501]. Structural prediction combined with histidine-residue mutagenesis and electrophysiology indicates that GRA72 assembles into a hexameric pore whose conserved pore-lining histidines are essential for function and channel conductance [PMID:38380952]. Loss of GRA72 produces an aberrant 'bubble vacuole' morphology with reduced PVM permeability, phenocopying loss of GRA17 [PMID:38380952, PMID:38936501], and GRA72 acts in a partially non-redundant pathway alongside GRA17/GRA23 to maintain PV integrity, with the Plasmodium falciparum ortholog PfExp2 fully cross-complementing the single knockouts [PMID:38936501]. GRA72 physically interacts with GRA47 at the PVM [PMID:38380952, PMID:38936501] and is synthetically lethal with GRA17 [PMID:37269286]. In the Pru strain, GRA72 deletion attenuates virulence in mice, reducing organ parasite load and brain cyst burden, establishing it as an in vivo virulence factor [PMID:39237959].","teleology":[{"year":2023,"claim":"Whether GRA72 functionally intersects with the known PVM permeability machinery was unknown; an in vivo genetic-interaction screen placed GRA72 in the GRA17 pathway by showing it is essential when GRA17 is lost.","evidence":"In vivo CRISPR screen in C57BL/6 and Ifngr1-/- mice identifying synthetic lethality with GRA17 and a role in GRA17/GRA23 localization","pmids":["37269286"],"confidence":"Medium","gaps":["Role in GRA17/GRA23 localization is a screen-level inference without direct localization experiments for GRA72","Molecular basis of the synthetic lethality not defined"],"attribution":[]},{"year":2024,"claim":"It was unknown what GRA72 does at the vacuole; knockout established it as a PVM/PV dense granule protein whose loss disrupts vacuole morphology and small-molecule flux, phenocopying GRA17 loss.","evidence":"Delta-gra72 knockout with vacuole morphology imaging and PVM small-molecule permeability assays, replicated across two labs","pmids":["38380952","38936501"],"confidence":"High","gaps":["Does not resolve whether the permeability defect is direct (pore) or indirect (mislocalization of partners)"],"attribution":[]},{"year":2024,"claim":"The physical basis of GRA72 action was unknown; structural and biophysical work showed it forms a hexameric pore with functionally essential histidines lining the channel.","evidence":"Computational structural prediction, site-directed mutagenesis of pore histidines, and electrophysiology of membrane conductance (single lab)","pmids":["38380952"],"confidence":"High","gaps":["Predicted hexamer lacks an experimental high-resolution structure","Ion/substrate selectivity of the pore not defined","Whether GRA72 forms a homo-hexamer or heteromeric assembly with GRA47/GRA17 unresolved"],"attribution":[]},{"year":2024,"claim":"The interaction network of GRA72 was undefined; reciprocal Co-IP identified GRA47 as a direct PVM binding partner.","evidence":"Immunoprecipitation/pulldown confirming GRA72-GRA47 interaction in two independent studies","pmids":["38380952","38936501"],"confidence":"High","gaps":["Stoichiometry and structural interface with GRA47 unknown","Whether GRA47 co-assembles into the pore is not established"],"attribution":[]},{"year":2024,"claim":"Whether GRA72 is functionally redundant with related GRAs was unknown; double-knockout and cross-species rescue showed GRA72, GRA17, GRA23 and GRA47 act in partially non-redundant but convergent pathways for PV morphology.","evidence":"Delta-gra23/Delta-gra72 double deletion, individual overexpression rescue, and PfExp2 cross-complementation with morphology quantification (single lab)","pmids":["38936501"],"confidence":"Medium","gaps":["Mechanistic reason each GRA only partially rescues while PfExp2 fully rescues not explained","Direct interplay between the GRA72 and GRA23 pathways undefined"],"attribution":[]},{"year":2024,"claim":"The in vivo importance of GRA72 was untested; Pru-strain knockout established it as a virulence factor required for normal parasite growth and cyst formation.","evidence":"Pru-Delta-gra72 knockout with mouse infection measuring survival, organ parasite load, and brain cyst burden","pmids":["39237959"],"confidence":"Medium","gaps":["Whether attenuation stems specifically from the permeability defect vs other functions not dissected","Strain-generality of the virulence phenotype beyond Pru untested"],"attribution":[]},{"year":2026,"claim":"Downstream consequences of GRA72 loss on parasite gene expression were unknown; transcriptomics linked GRA72 deletion to bradyzoite-associated and metabolic gene reprogramming.","evidence":"RNA-seq of Pru-Delta-gra72 vs wild-type with RT-qPCR validation, showing 858 DEGs enriched in membrane and metabolic pathways","pmids":["42068418"],"confidence":"Low","gaps":["Expression-level correlation only; no direct mechanistic link between GRA72 protein and the affected metabolic or membrane pathways","Cannot distinguish primary transcriptional effect from secondary consequence of stage conversion","Single lab, single strain"],"attribution":[]},{"year":null,"claim":"How the GRA72 pore mediates selective small-molecule transport and how it assembles with GRA47/GRA17 into a functional PVM channel complex remain unresolved.","evidence":"","pmids":[],"confidence":"Low","gaps":["No experimental atomic structure of the pore or its complexes","Transported substrate spectrum and selectivity undefined","Regulation of pore assembly and gating unknown"],"attribution":[]}],"mechanism_profile":{"molecular_activity":[],"localization":[],"pathway":[],"complexes":["GRA72-GRA47 PVM complex"],"partners":["GRA47","GRA17","GRA23"],"other_free_text":["Forms a predicted hexameric pore with conserved pore-lining histidine residues essential for function and membrane conductance [#2]","Synthetically lethal with GRA17 and functions in a partially non-redundant pathway with GRA17/GRA23/GRA47 for PV morphology and PVM permeability [#3, #5]","Functionally cross-complemented by Plasmodium falciparum PfExp2 [#5]","Virulence factor required for normal in vivo growth and brain cyst burden in the Pru strain [#4]"]},"strain_conflicts":[]},"prefetch_data":{},"corpus_meta":[{"pmid":"37269286","id":"PMC_37269286","title":"Host genetics highlights IFN-γ-dependent Toxoplasma genes encoding secreted and non-secreted virulence factors in in vivo CRISPR screens.","date":"2023","source":"Cell reports","url":"https://pubmed.ncbi.nlm.nih.gov/37269286","citation_count":30,"is_preprint":false},{"pmid":"38380952","id":"PMC_38380952","title":"Two Toxoplasma gondii putative pore-forming proteins, GRA47 and GRA72, influence small molecule permeability of the parasitophorous vacuole.","date":"2024","source":"mBio","url":"https://pubmed.ncbi.nlm.nih.gov/38380952","citation_count":24,"is_preprint":false},{"pmid":"38936501","id":"PMC_38936501","title":"GRA47 is important for the morphology and permeability of the parasitophorous vacuole in Toxoplasma gondii.","date":"2024","source":"International journal for parasitology","url":"https://pubmed.ncbi.nlm.nih.gov/38936501","citation_count":11,"is_preprint":false},{"pmid":"39237959","id":"PMC_39237959","title":"Live-attenuated PruΔgra72 strain of Toxoplasma gondii induces strong protective immunity against acute and chronic toxoplasmosis in mice.","date":"2024","source":"Parasites & vectors","url":"https://pubmed.ncbi.nlm.nih.gov/39237959","citation_count":6,"is_preprint":false},{"pmid":"38014337","id":"PMC_38014337","title":"GRA47 and GRA72 are Toxoplasma gondii pore-forming proteins that influence small molecule permeability of the parasitophorous vacuole.","date":"2023","source":"bioRxiv : the preprint server for biology","url":"https://pubmed.ncbi.nlm.nih.gov/38014337","citation_count":1,"is_preprint":false},{"pmid":"42068418","id":"PMC_42068418","title":"Toxoplasma GRA72 is Involved in Membrane-Associated Functions and Metabolic Homeostasis Revealed by Transcriptomic Analysis.","date":"2026","source":"Acta parasitologica","url":"https://pubmed.ncbi.nlm.nih.gov/42068418","citation_count":0,"is_preprint":false},{"pmid":"42252477","id":"PMC_42252477","title":"Gene-edited live-attenuated vaccines against Toxoplasma gondii: recent advances and future frontiers.","date":"2026","source":"Parasites & vectors","url":"https://pubmed.ncbi.nlm.nih.gov/42252477","citation_count":0,"is_preprint":false},{"pmid":"42253329","id":"PMC_42253329","title":"Protective Immunity Induced by DNA Vaccines Encoding TgGRA47 and TgGRA72 Against Toxoplasma gondii Infection in BALB/c Mice.","date":"2026","source":"Transboundary and emerging diseases","url":"https://pubmed.ncbi.nlm.nih.gov/42253329","citation_count":0,"is_preprint":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":6993,"output_tokens":1928,"usd":0.024949,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":7212,"output_tokens":2943,"usd":0.054817,"stage2_stop_reason":"end_turn"},"total_usd":0.079766,"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\": 2024,\n      \"finding\": \"GRA72 is a dense granule protein that localizes to the parasitophorous vacuole membrane (PVM) and parasitophorous vacuole (PV), and deletion of GRA72 produces an aberrant 'bubble vacuole' morphology with reduced small molecule permeability across the PVM, similar to deletion of GRA17.\",\n      \"method\": \"Gene knockout (Δgra72) with vacuole morphology imaging and small molecule permeability assays\",\n      \"journal\": \"mBio\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — loss-of-function genetic deletion with defined cellular phenotype (aberrant PV morphology, reduced PVM permeability), replicated across two independent labs (PMID:38380952, PMID:38936501)\",\n      \"pmids\": [\"38380952\", \"38936501\"],\n      \"is_preprint\": false,\n      \"attribution\": [\n        {\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}\n      ]\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"GRA72 physically interacts with GRA47, as determined by immunoprecipitation; GRA47 is identified as a binding partner of GRA72 at the PVM.\",\n      \"method\": \"Immunoprecipitation (Co-IP) / pulldown\",\n      \"journal\": \"mBio\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — reciprocal Co-IP confirmed in two independent studies (PMID:38380952, PMID:38936501)\",\n      \"pmids\": [\"38380952\", \"38936501\"],\n      \"is_preprint\": false,\n      \"attribution\": [\n        {\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}\n      ]\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"Structural predictions indicate GRA72 forms a hexameric pore with conserved histidine residues lining the pore; mutational analysis of these histidines demonstrated they are critical for GRA72 functionality, and electrophysiology confirmed alterations in membrane conductance consistent with pore-forming activity.\",\n      \"method\": \"Computational structural prediction, site-directed mutagenesis of histidine residues, electrophysiology\",\n      \"journal\": \"mBio\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — structural prediction combined with mutagenesis and electrophysiological validation in a single rigorous study, single lab\",\n      \"pmids\": [\"38380952\"],\n      \"is_preprint\": false,\n      \"attribution\": [\n        {\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}\n      ]\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"GRA72 was identified as synthetically lethal with GRA17 in an in vivo CRISPR screen, and screen results suggest GRA72 plays a role in normal GRA17/GRA23 localization at the PVM.\",\n      \"method\": \"In vivo CRISPR screen in mice (C57BL/6 and Ifngr1−/− hosts)\",\n      \"journal\": \"Cell reports\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Weak — in vivo CRISPR screen with genetic epistasis evidence, but the role in GRA17/GRA23 localization is a screen-level inference from a single study without direct localization experiments shown for GRA72\",\n      \"pmids\": [\"37269286\"],\n      \"is_preprint\": false,\n      \"attribution\": [\n        {\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}\n      ]\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"Deletion of GRA72 in the Pru strain (PruΔgra72) results in attenuated virulence in mice, with significantly decreased parasite load in organs and reduced brain cyst burden, establishing GRA72 as a virulence factor required for normal in vivo growth.\",\n      \"method\": \"Gene knockout (PruΔgra72) with in vivo mouse infection assays measuring survival, organ parasite load, and brain cyst burden\",\n      \"journal\": \"Parasites & vectors\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — clean KO with defined in vivo phenotype, single lab, replicated across multiple mouse experiments\",\n      \"pmids\": [\"39237959\"],\n      \"is_preprint\": false,\n      \"attribution\": [\n        {\"species\": \"Toxoplasma gondii\", \"strain\": \"Pru\"}\n      ]\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"In the Δgra23Δgra72 double knockout strain, the proportion of aberrant PVs was significantly increased compared to Δgra23 alone, indicating GRA72 and GRA23 function in partially non-redundant pathways to maintain PV morphology. Overexpression of GRA17, GRA47, or GRA72 individually only partially rescued aberrant PV morphology in Δgra47, Δgra72, or Δgra17, while the Plasmodium falciparum PVM protein PfExp2 (ortholog of GRA17/GRA23) fully rescued all three single knockouts.\",\n      \"method\": \"Double gene deletion, overexpression rescue experiments, morphology quantification\",\n      \"journal\": \"International journal for parasitology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genetic epistasis via double KO and rescue experiments, single lab, multiple orthogonal approaches\",\n      \"pmids\": [\"38936501\"],\n      \"is_preprint\": false,\n      \"attribution\": [\n        {\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}\n      ]\n    },\n    {\n      \"year\": 2026,\n      \"finding\": \"Transcriptomic analysis (RNA-seq) of PruΔgra72 compared to wild-type Pru revealed 858 differentially expressed genes, with upregulation of bradyzoite-associated genes and bidirectional regulation of dense granule proteins (GRAs); DEGs were enriched in membrane-related functional categories and key metabolic pathways (fatty acid, carbon, and amino acid metabolism), implicating GRA72 in membrane-associated functions and metabolic homeostasis.\",\n      \"method\": \"RNA-seq transcriptomic analysis of knockout strain vs. wild-type, validated by RT-qPCR\",\n      \"journal\": \"Acta parasitologica\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 4 / Weak — transcriptomic/expression-based analysis; no direct mechanistic experiments linking GRA72 protein to specific metabolic or membrane pathways, single lab\",\n      \"pmids\": [\"42068418\"],\n      \"is_preprint\": false,\n      \"attribution\": [\n        {\"species\": \"Toxoplasma gondii\", \"strain\": \"Pru\"}\n      ]\n    }\n  ],\n  \"current_model\": \"GRA72 is a dense granule protein that localizes to the parasitophorous vacuole membrane (PVM) and forms a hexameric pore (with critical histidine residues lining the channel) that regulates small molecule permeability across the PVM; it physically interacts with GRA47, acts in a partially non-redundant pathway alongside GRA17 and GRA23 to maintain PV morphology and nutrient flux, is synthetically lethal with GRA17, and is required for normal in vivo virulence in Toxoplasma gondii.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"GRA72 is a Toxoplasma gondii dense granule protein that governs small-molecule permeability across the parasitophorous vacuole membrane (PVM), where it localizes together with the PV [#0]. Structural prediction combined with histidine-residue mutagenesis and electrophysiology indicates that GRA72 assembles into a hexameric pore whose conserved pore-lining histidines are essential for function and channel conductance [#2]. Loss of GRA72 produces an aberrant 'bubble vacuole' morphology with reduced PVM permeability, phenocopying loss of GRA17 [#0], and GRA72 acts in a partially non-redundant pathway alongside GRA17/GRA23 to maintain PV integrity, with the Plasmodium falciparum ortholog PfExp2 fully cross-complementing the single knockouts [#5]. GRA72 physically interacts with GRA47 at the PVM [#1] and is synthetically lethal with GRA17 [#3]. In the Pru strain, GRA72 deletion attenuates virulence in mice, reducing organ parasite load and brain cyst burden, establishing it as an in vivo virulence factor [#4].\",\n  \"teleology\": [\n    {\n      \"year\": 2023,\n      \"claim\": \"Whether GRA72 functionally intersects with the known PVM permeability machinery was unknown; an in vivo genetic-interaction screen placed GRA72 in the GRA17 pathway by showing it is essential when GRA17 is lost.\",\n      \"evidence\": \"In vivo CRISPR screen in C57BL/6 and Ifngr1-/- mice identifying synthetic lethality with GRA17 and a role in GRA17/GRA23 localization\",\n      \"pmids\": [\"37269286\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Role in GRA17/GRA23 localization is a screen-level inference without direct localization experiments for GRA72\", \"Molecular basis of the synthetic lethality not defined\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"It was unknown what GRA72 does at the vacuole; knockout established it as a PVM/PV dense granule protein whose loss disrupts vacuole morphology and small-molecule flux, phenocopying GRA17 loss.\",\n      \"evidence\": \"Delta-gra72 knockout with vacuole morphology imaging and PVM small-molecule permeability assays, replicated across two labs\",\n      \"pmids\": [\"38380952\", \"38936501\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Does not resolve whether the permeability defect is direct (pore) or indirect (mislocalization of partners)\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"The physical basis of GRA72 action was unknown; structural and biophysical work showed it forms a hexameric pore with functionally essential histidines lining the channel.\",\n      \"evidence\": \"Computational structural prediction, site-directed mutagenesis of pore histidines, and electrophysiology of membrane conductance (single lab)\",\n      \"pmids\": [\"38380952\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Predicted hexamer lacks an experimental high-resolution structure\", \"Ion/substrate selectivity of the pore not defined\", \"Whether GRA72 forms a homo-hexamer or heteromeric assembly with GRA47/GRA17 unresolved\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"The interaction network of GRA72 was undefined; reciprocal Co-IP identified GRA47 as a direct PVM binding partner.\",\n      \"evidence\": \"Immunoprecipitation/pulldown confirming GRA72-GRA47 interaction in two independent studies\",\n      \"pmids\": [\"38380952\", \"38936501\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Stoichiometry and structural interface with GRA47 unknown\", \"Whether GRA47 co-assembles into the pore is not established\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Whether GRA72 is functionally redundant with related GRAs was unknown; double-knockout and cross-species rescue showed GRA72, GRA17, GRA23 and GRA47 act in partially non-redundant but convergent pathways for PV morphology.\",\n      \"evidence\": \"Delta-gra23/Delta-gra72 double deletion, individual overexpression rescue, and PfExp2 cross-complementation with morphology quantification (single lab)\",\n      \"pmids\": [\"38936501\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Mechanistic reason each GRA only partially rescues while PfExp2 fully rescues not explained\", \"Direct interplay between the GRA72 and GRA23 pathways undefined\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"The in vivo importance of GRA72 was untested; Pru-strain knockout established it as a virulence factor required for normal parasite growth and cyst formation.\",\n      \"evidence\": \"Pru-Delta-gra72 knockout with mouse infection measuring survival, organ parasite load, and brain cyst burden\",\n      \"pmids\": [\"39237959\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Whether attenuation stems specifically from the permeability defect vs other functions not dissected\", \"Strain-generality of the virulence phenotype beyond Pru untested\"]\n    },\n    {\n      \"year\": 2026,\n      \"claim\": \"Downstream consequences of GRA72 loss on parasite gene expression were unknown; transcriptomics linked GRA72 deletion to bradyzoite-associated and metabolic gene reprogramming.\",\n      \"evidence\": \"RNA-seq of Pru-Delta-gra72 vs wild-type with RT-qPCR validation, showing 858 DEGs enriched in membrane and metabolic pathways\",\n      \"pmids\": [\"42068418\"],\n      \"confidence\": \"Low\",\n      \"gaps\": [\"Expression-level correlation only; no direct mechanistic link between GRA72 protein and the affected metabolic or membrane pathways\", \"Cannot distinguish primary transcriptional effect from secondary consequence of stage conversion\", \"Single lab, single strain\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How the GRA72 pore mediates selective small-molecule transport and how it assembles with GRA47/GRA17 into a functional PVM channel complex remain unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Low\",\n      \"gaps\": [\"No experimental atomic structure of the pore or its complexes\", \"Transported substrate spectrum and selectivity undefined\", \"Regulation of pore assembly and gating unknown\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0015267\", \"supporting_discovery_ids\": [0, 2], \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]},\n      {\"term_id\": \"GO:0005515\", \"supporting_discovery_ids\": [1], \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0020005\", \"supporting_discovery_ids\": [0], \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]},\n      {\"term_id\": \"GO:0020003\", \"supporting_discovery_ids\": [0], \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"GO:0055085\", \"supporting_discovery_ids\": [0, 2, 5], \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]}\n    ],\n    \"complexes\": [\"GRA72-GRA47 PVM complex\"],\n    \"partners\": [\"GRA47\", \"GRA17\", \"GRA23\"],\n    \"other_free_text\": [\n      \"Forms a predicted hexameric pore with conserved pore-lining histidine residues essential for function and membrane conductance [#2]\",\n      \"Synthetically lethal with GRA17 and functions in a partially non-redundant pathway with GRA17/GRA23/GRA47 for PV morphology and PVM permeability [#3, #5]\",\n      \"Functionally cross-complemented by Plasmodium falciparum PfExp2 [#5]\",\n      \"Virulence factor required for normal in vivo growth and brain cyst burden in the Pru strain [#4]\"\n    ]\n  },\n  \"strain_conflicts\": []\n}","audit_flag":null,"strains":[{"strain":"ME49","gene_id":"TGME49_272460","name":"GRA72","product":"dense granule protein GRA72","uniprot_acc":"S8F501","chromosome":"TGME49_chrVIII","start_pos":3958098},{"strain":"GT1","gene_id":"TGGT1_272460","name":null,"product":"hypothetical protein","uniprot_acc":null,"chromosome":"TGGT1_chrVIII","start_pos":3956208},{"strain":"RH88","gene_id":"TGRH88_079250","name":null,"product":"unspecified product","uniprot_acc":null,"chromosome":"CM023089","start_pos":9067705},{"strain":"VEG","gene_id":"TGVEG_272460","name":null,"product":"putative transmembrane protein","uniprot_acc":"B9PIE0","chromosome":"TGVEG_chrVIII","start_pos":3968244}]}