{"gene":"TG_293870","gene_symbol":"TRX1","run_date":"2026-09-08T14:08:30","timeline":{"discoveries":[{"year":2025,"finding":"TgTrx1 contains a conserved -CXXC- catalytic motif and localizes mainly to the cytoplasm of T. gondii tachyzoites, consistent with a thioredoxin-family redox enzyme.","method":"Protein characterization (sequence analysis of catalytic motif) and subcellular localization by direct imaging/fractionation","journal":"International journal for parasitology","confidence":"Medium","confidence_rationale":"Tier 2 / Weak — direct localization experiment with functional context, single lab, single paper","pmids":["40885463"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":"RH"}]},{"year":2025,"finding":"CRISPR-Cas9 knockout of TgTrx1 (RHΔtrx1) caused marked defects in host cell invasion, microneme protein secretion, intracellular replication, egress, and oxidative stress tolerance, establishing TgTrx1 as essential for these parasite processes.","method":"CRISPR-Cas9 gene knockout with invasion assays, microneme secretion assays, replication assays, egress assays, and oxidative stress survival assays","journal":"International journal for parasitology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — clean KO with multiple orthogonal phenotypic readouts, single lab","pmids":["40885463"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":"RH"}]},{"year":2025,"finding":"Loss of TgTrx1 produced abnormal mitochondrial morphology and asynchronous cell division, placing TgTrx1 upstream of mitochondrial integrity and synchronous parasite cell division.","method":"CRISPR-Cas9 knockout with microscopic analysis of mitochondrial morphology and cell division timing","journal":"International journal for parasitology","confidence":"Medium","confidence_rationale":"Tier 2 / Weak — clean KO with direct microscopic phenotypic readout, single lab, single paper","pmids":["40885463"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":"RH"}]},{"year":2025,"finding":"Transcriptomic analysis of RHΔtrx1 parasites revealed significant changes in expression of genes involved in oxidative stress response and bradyzoite differentiation, placing TgTrx1 in the regulatory network controlling redox homeostasis and stage conversion.","method":"CRISPR-Cas9 knockout followed by transcriptomic (RNA-seq) analysis","journal":"International journal for parasitology","confidence":"Low","confidence_rationale":"Tier 3 / Weak — transcriptomics provides pathway placement but is indirect; single lab, single method","pmids":["40885463"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":"RH"}]}],"current_model":"TgTrx1 is a cytoplasmic thioredoxin with a conserved -CXXC- catalytic motif that functions as a multifunctional redox protein in T. gondii tachyzoites, required for oxidative stress tolerance, host cell invasion, microneme secretion, intracellular replication, egress, mitochondrial integrity, and synchronous cell division, with its loss also dysregulating transcriptional programs governing oxidative stress response and bradyzoite differentiation."},"narrative":{"mechanistic_narrative":"TgTrx1 is a cytoplasmic thioredoxin-family redox enzyme of Toxoplasma gondii tachyzoites that couples redox homeostasis to the core lytic cycle and stage differentiation program of the parasite [PMID:40885463]. It bears a conserved -CXXC- catalytic motif consistent with thioredoxin oxidoreductase activity and localizes mainly to the cytoplasm [PMID:40885463]. CRISPR-Cas9 disruption in the RH strain establishes that TgTrx1 is required for oxidative stress tolerance, host cell invasion, microneme protein secretion, intracellular replication, and egress [PMID:40885463], and its loss disrupts mitochondrial morphology and the synchrony of parasite cell division [PMID:40885463]. Consistent with a broad regulatory role, transcriptomic profiling of knockout parasites shows dysregulation of oxidative stress response and bradyzoite differentiation genes [PMID:40885463]. Beyond these knockout phenotypes and its catalytic motif, the direct molecular substrates and enzymatic partners of TgTrx1 have not been characterized in the available corpus.","teleology":[{"year":2025,"claim":"Establishing whether the gene product is a bona fide thioredoxin and where it acts required defining its catalytic motif and localization, which anchored it as a cytoplasmic redox enzyme.","evidence":"Sequence analysis of the -CXXC- catalytic motif and subcellular localization by imaging/fractionation in T. gondii RH tachyzoites","pmids":["40885463"],"confidence":"Medium","gaps":["No direct demonstration of oxidoreductase activity or identified reducing substrates","No identified redox partners (e.g., thioredoxin reductase, target proteins)","Localization resolved only to cytoplasm; finer compartment associations not defined"],"attribution":[{"species":"Toxoplasma gondii","strain":"RH"}]},{"year":2025,"claim":"Whether TgTrx1 is functionally required for the lytic cycle was answered by clean knockout, showing it is essential for invasion, microneme secretion, replication, egress, and oxidative stress survival.","evidence":"CRISPR-Cas9 knockout (RHΔtrx1) with invasion, microneme secretion, replication, egress, and oxidative stress survival assays","pmids":["40885463"],"confidence":"Medium","gaps":["Phenotypes not linked to specific molecular substrates of TgTrx1","Complementation/rescue not described to confirm on-target causality","Not tested in strains beyond RH"],"attribution":[{"species":"Toxoplasma gondii","strain":"RH"}]},{"year":2025,"claim":"To place TgTrx1 relative to organellar and cell-cycle processes, knockout parasites were examined microscopically, revealing abnormal mitochondrial morphology and asynchronous division.","evidence":"CRISPR-Cas9 knockout with microscopy of mitochondrial morphology and cell division timing in RH","pmids":["40885463"],"confidence":"Medium","gaps":["Whether mitochondrial and division defects are direct or downstream of general redox stress is unresolved","No mechanistic link between TgTrx1 activity and division machinery"],"attribution":[{"species":"Toxoplasma gondii","strain":"RH"}]},{"year":2025,"claim":"Transcriptomics placed TgTrx1 in a regulatory network by showing its loss dysregulates oxidative stress response and bradyzoite differentiation genes.","evidence":"RNA-seq of RHΔtrx1 knockout parasites","pmids":["40885463"],"confidence":"Low","gaps":["Transcriptomic association is indirect and does not establish a direct regulatory mechanism","No demonstration that TgTrx1 acts on transcriptional regulators of stage conversion","Bradyzoite differentiation not functionally assayed"],"attribution":[{"species":"Toxoplasma gondii","strain":"RH"}]},{"year":null,"claim":"The direct enzymatic substrates and redox partners through which TgTrx1 controls invasion, mitochondrial integrity, division, and stage conversion remain unidentified.","evidence":"","pmids":[],"confidence":"Low","gaps":["No biochemical demonstration of thioredoxin oxidoreductase activity","No identified target proteins reduced by TgTrx1","No characterization outside the RH strain"],"attribution":[{"species":"Toxoplasma gondii","strain":"RH"}]}],"mechanism_profile":{"molecular_activity":[],"localization":[],"pathway":[],"complexes":[],"partners":[],"other_free_text":["Required for host cell invasion, microneme secretion, intracellular replication, and egress [#1]","Required for mitochondrial integrity and synchronous cell division [#2]","Loss dysregulates oxidative stress response and bradyzoite differentiation gene expression [#3]"]},"strain_conflicts":[]},"prefetch_data":{},"corpus_meta":[{"pmid":"40885463","id":"PMC_40885463","title":"A novel Toxoplasma gondii thioredoxin (TgTrx1) is important for parasite fitness and virulence.","date":"2025","source":"International journal for parasitology","url":"https://pubmed.ncbi.nlm.nih.gov/40885463","citation_count":1,"is_preprint":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":2972,"output_tokens":1016,"usd":0.012078,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":5908,"output_tokens":2154,"usd":0.041695,"stage2_stop_reason":"end_turn"},"total_usd":0.053773,"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\": 2025,\n      \"finding\": \"TgTrx1 contains a conserved -CXXC- catalytic motif and localizes mainly to the cytoplasm of T. gondii tachyzoites, consistent with a thioredoxin-family redox enzyme.\",\n      \"method\": \"Protein characterization (sequence analysis of catalytic motif) and subcellular localization by direct imaging/fractionation\",\n      \"journal\": \"International journal for parasitology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Weak — direct localization experiment with functional context, single lab, single paper\",\n      \"pmids\": [\"40885463\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"RH\"}]\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"CRISPR-Cas9 knockout of TgTrx1 (RHΔtrx1) caused marked defects in host cell invasion, microneme protein secretion, intracellular replication, egress, and oxidative stress tolerance, establishing TgTrx1 as essential for these parasite processes.\",\n      \"method\": \"CRISPR-Cas9 gene knockout with invasion assays, microneme secretion assays, replication assays, egress assays, and oxidative stress survival assays\",\n      \"journal\": \"International journal for parasitology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — clean KO with multiple orthogonal phenotypic readouts, single lab\",\n      \"pmids\": [\"40885463\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"RH\"}]\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"Loss of TgTrx1 produced abnormal mitochondrial morphology and asynchronous cell division, placing TgTrx1 upstream of mitochondrial integrity and synchronous parasite cell division.\",\n      \"method\": \"CRISPR-Cas9 knockout with microscopic analysis of mitochondrial morphology and cell division timing\",\n      \"journal\": \"International journal for parasitology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Weak — clean KO with direct microscopic phenotypic readout, single lab, single paper\",\n      \"pmids\": [\"40885463\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"RH\"}]\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"Transcriptomic analysis of RHΔtrx1 parasites revealed significant changes in expression of genes involved in oxidative stress response and bradyzoite differentiation, placing TgTrx1 in the regulatory network controlling redox homeostasis and stage conversion.\",\n      \"method\": \"CRISPR-Cas9 knockout followed by transcriptomic (RNA-seq) analysis\",\n      \"journal\": \"International journal for parasitology\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — transcriptomics provides pathway placement but is indirect; single lab, single method\",\n      \"pmids\": [\"40885463\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"RH\"}]\n    }\n  ],\n  \"current_model\": \"TgTrx1 is a cytoplasmic thioredoxin with a conserved -CXXC- catalytic motif that functions as a multifunctional redox protein in T. gondii tachyzoites, required for oxidative stress tolerance, host cell invasion, microneme secretion, intracellular replication, egress, mitochondrial integrity, and synchronous cell division, with its loss also dysregulating transcriptional programs governing oxidative stress response and bradyzoite differentiation.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"TgTrx1 is a cytoplasmic thioredoxin-family redox enzyme of Toxoplasma gondii tachyzoites that couples redox homeostasis to the core lytic cycle and stage differentiation program of the parasite [#0, #1]. It bears a conserved -CXXC- catalytic motif consistent with thioredoxin oxidoreductase activity and localizes mainly to the cytoplasm [#0]. CRISPR-Cas9 disruption in the RH strain establishes that TgTrx1 is required for oxidative stress tolerance, host cell invasion, microneme protein secretion, intracellular replication, and egress [#1], and its loss disrupts mitochondrial morphology and the synchrony of parasite cell division [#2]. Consistent with a broad regulatory role, transcriptomic profiling of knockout parasites shows dysregulation of oxidative stress response and bradyzoite differentiation genes [#3]. Beyond these knockout phenotypes and its catalytic motif, the direct molecular substrates and enzymatic partners of TgTrx1 have not been characterized in the available corpus.\",\n  \"teleology\": [\n    {\n      \"year\": 2025,\n      \"claim\": \"Establishing whether the gene product is a bona fide thioredoxin and where it acts required defining its catalytic motif and localization, which anchored it as a cytoplasmic redox enzyme.\",\n      \"evidence\": \"Sequence analysis of the -CXXC- catalytic motif and subcellular localization by imaging/fractionation in T. gondii RH tachyzoites\",\n      \"pmids\": [\"40885463\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"No direct demonstration of oxidoreductase activity or identified reducing substrates\",\n        \"No identified redox partners (e.g., thioredoxin reductase, target proteins)\",\n        \"Localization resolved only to cytoplasm; finer compartment associations not defined\"\n      ],\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"RH\"}]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Whether TgTrx1 is functionally required for the lytic cycle was answered by clean knockout, showing it is essential for invasion, microneme secretion, replication, egress, and oxidative stress survival.\",\n      \"evidence\": \"CRISPR-Cas9 knockout (RH\\u0394trx1) with invasion, microneme secretion, replication, egress, and oxidative stress survival assays\",\n      \"pmids\": [\"40885463\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"Phenotypes not linked to specific molecular substrates of TgTrx1\",\n        \"Complementation/rescue not described to confirm on-target causality\",\n        \"Not tested in strains beyond RH\"\n      ],\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"RH\"}]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"To place TgTrx1 relative to organellar and cell-cycle processes, knockout parasites were examined microscopically, revealing abnormal mitochondrial morphology and asynchronous division.\",\n      \"evidence\": \"CRISPR-Cas9 knockout with microscopy of mitochondrial morphology and cell division timing in RH\",\n      \"pmids\": [\"40885463\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"Whether mitochondrial and division defects are direct or downstream of general redox stress is unresolved\",\n        \"No mechanistic link between TgTrx1 activity and division machinery\"\n      ],\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"RH\"}]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Transcriptomics placed TgTrx1 in a regulatory network by showing its loss dysregulates oxidative stress response and bradyzoite differentiation genes.\",\n      \"evidence\": \"RNA-seq of RH\\u0394trx1 knockout parasites\",\n      \"pmids\": [\"40885463\"],\n      \"confidence\": \"Low\",\n      \"gaps\": [\n        \"Transcriptomic association is indirect and does not establish a direct regulatory mechanism\",\n        \"No demonstration that TgTrx1 acts on transcriptional regulators of stage conversion\",\n        \"Bradyzoite differentiation not functionally assayed\"\n      ],\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"RH\"}]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"The direct enzymatic substrates and redox partners through which TgTrx1 controls invasion, mitochondrial integrity, division, and stage conversion remain unidentified.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Low\",\n      \"gaps\": [\n        \"No biochemical demonstration of thioredoxin oxidoreductase activity\",\n        \"No identified target proteins reduced by TgTrx1\",\n        \"No characterization outside the RH strain\"\n      ],\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"RH\"}]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0015035\", \"supporting_discovery_ids\": [0], \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"RH\"}]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005737\", \"supporting_discovery_ids\": [0], \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"RH\"}]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"GO:0006979\", \"supporting_discovery_ids\": [1, 3], \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"RH\"}]}\n    ],\n    \"complexes\": [],\n    \"partners\": [],\n    \"other_free_text\": [\n      \"Required for host cell invasion, microneme secretion, intracellular replication, and egress [#1]\",\n      \"Required for mitochondrial integrity and synchronous cell division [#2]\",\n      \"Loss dysregulates oxidative stress response and bradyzoite differentiation gene expression [#3]\"\n    ]\n  },\n  \"strain_conflicts\": []\n}","audit_flag":null,"strains":[{"strain":"ME49","gene_id":"TGME49_293870","name":"TRX1","product":"thioredoxin 1","uniprot_acc":"A0A125YIY3","chromosome":"TGME49_chrIa","start_pos":618935},{"strain":"GT1","gene_id":"TGGT1_293870","name":null,"product":"putative thioredoxin","uniprot_acc":null,"chromosome":"TGGT1_chrIa","start_pos":604538},{"strain":"RH88","gene_id":"TGRH88_019160","name":null,"product":"putative thioredoxin","uniprot_acc":null,"chromosome":"CM023081","start_pos":624705},{"strain":"VEG","gene_id":"TGVEG_293870","name":null,"product":"putative thioredoxin","uniprot_acc":"A0A0F7UN03","chromosome":"TGVEG_chrIa","start_pos":628154}]}