{"gene":"TG_305520","gene_symbol":"RPS2","run_date":"2026-09-08T15:15:13","timeline":{"discoveries":[{"year":2021,"finding":"TgRPS2 (ribosomal protein S2) localizes to the apical end of Toxoplasma gondii tachyzoites, as determined by immunofluorescence assay, and is secreted as a circulating antigen detectable in serum of infected mice.","method":"Immunofluorescence assay (localization); immunoprecipitation-LC-MS/MS (identification as circulating antigen); Western blotting (detection in serum)","journal":"Frontiers in microbiology","confidence":"Low","confidence_rationale":"Tier 3 / Weak — single lab, localization by IFA without functional follow-up, no mechanistic pathway placement","pmids":["33537014"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":"RH"}]}],"current_model":"TgRPS2 is a ribosomal protein of Toxoplasma gondii that localizes to the apical end of tachyzoites and is released as a circulating antigen during acute infection, but no detailed molecular mechanism or functional role beyond antigen recognition has been experimentally established."},"narrative":{"mechanistic_narrative":"TgRPS2 is a ribosomal protein S2 homolog of Toxoplasma gondii identified as a circulating antigen during acute infection [PMID:33537014]. In RH-strain tachyzoites it localizes to the apical end and is secreted, being detectable in the serum of infected mice [PMID:33537014]. Beyond this localization and its recognition as a circulating antigen [PMID:33537014], no molecular mechanism or functional role has been characterized in the available corpus.","teleology":[{"year":2021,"claim":"Establishing where TgRPS2 resides in the parasite and whether it reaches host circulation addressed whether a ribosomal protein could serve as an accessible infection marker; the work showed apical localization and secretion into serum, establishing TgRPS2 as a circulating antigen of acute toxoplasmosis.","evidence":"Immunofluorescence for localization, immunoprecipitation-LC-MS/MS for antigen identification, and Western blotting for serum detection in T. gondii RH-infected mice","pmids":["33537014"],"confidence":"Low","gaps":["Single lab, localization by IFA without functional follow-up or reciprocal validation","No mechanistic pathway placement or defined molecular function beyond antigen recognition","Mechanism of apical targeting and secretion of a ribosomal protein is unresolved"],"attribution":[{"species":"Toxoplasma gondii","strain":"RH"}]},{"year":null,"claim":"The molecular function of TgRPS2 beyond its identity as a secreted antigen, and how a ribosomal protein comes to localize apically and enter host circulation, remain unknown.","evidence":"","pmids":[],"confidence":"Low","gaps":["No functional characterization or knockout phenotype","No binding partners or pathway placement established","Secretion mechanism uncharacterized"],"attribution":[{"species":"Toxoplasma gondii","strain":"RH"}]}],"mechanism_profile":{"molecular_activity":[],"localization":[],"pathway":[],"complexes":[],"partners":[],"other_free_text":["Identified as a circulating antigen detectable in serum of T. gondii RH-infected mice [#0]"]},"strain_conflicts":[]},"prefetch_data":{},"corpus_meta":[{"pmid":"33537014","id":"PMC_33537014","title":"Study on Circulating Antigens in Serum of Mice With Experimental Acute Toxoplasmosis.","date":"2021","source":"Frontiers in microbiology","url":"https://pubmed.ncbi.nlm.nih.gov/33537014","citation_count":4,"is_preprint":false},{"pmid":"39416787","id":"PMC_39416787","title":"Nanospheres as the delivery vehicle: novel application of Toxoplasma gondii ribosomal protein S2 in PLGA and chitosan nanospheres against acute toxoplasmosis.","date":"2024","source":"Frontiers in immunology","url":"https://pubmed.ncbi.nlm.nih.gov/39416787","citation_count":3,"is_preprint":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":3542,"output_tokens":339,"usd":0.007855,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":4905,"output_tokens":1022,"usd":0.025038,"stage2_stop_reason":"end_turn"},"total_usd":0.032893,"stage1_batch_id":"msgbatch_01S6GjoYQm8LTPUsdhASdqag","stage2_batch_id":"msgbatch_01VX63RTMdBJqsG6gQMqoCjz","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2021,\n      \"finding\": \"TgRPS2 (ribosomal protein S2) localizes to the apical end of Toxoplasma gondii tachyzoites, as determined by immunofluorescence assay, and is secreted as a circulating antigen detectable in serum of infected mice.\",\n      \"method\": \"Immunofluorescence assay (localization); immunoprecipitation-LC-MS/MS (identification as circulating antigen); Western blotting (detection in serum)\",\n      \"journal\": \"Frontiers in microbiology\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — single lab, localization by IFA without functional follow-up, no mechanistic pathway placement\",\n      \"pmids\": [\"33537014\"],\n      \"is_preprint\": false,\n      \"attribution\": [\n        {\"species\": \"Toxoplasma gondii\", \"strain\": \"RH\"}\n      ]\n    }\n  ],\n  \"current_model\": \"TgRPS2 is a ribosomal protein of Toxoplasma gondii that localizes to the apical end of tachyzoites and is released as a circulating antigen during acute infection, but no detailed molecular mechanism or functional role beyond antigen recognition has been experimentally established.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"TgRPS2 is a ribosomal protein S2 homolog of Toxoplasma gondii identified as a circulating antigen during acute infection [#0]. In RH-strain tachyzoites it localizes to the apical end and is secreted, being detectable in the serum of infected mice [#0]. Beyond this localization and its recognition as a circulating antigen [#0], no molecular mechanism or functional role has been characterized in the available corpus.\",\n  \"teleology\": [\n    {\n      \"year\": 2021,\n      \"claim\": \"Establishing where TgRPS2 resides in the parasite and whether it reaches host circulation addressed whether a ribosomal protein could serve as an accessible infection marker; the work showed apical localization and secretion into serum, establishing TgRPS2 as a circulating antigen of acute toxoplasmosis.\",\n      \"evidence\": \"Immunofluorescence for localization, immunoprecipitation-LC-MS/MS for antigen identification, and Western blotting for serum detection in T. gondii RH-infected mice\",\n      \"pmids\": [\"33537014\"],\n      \"confidence\": \"Low\",\n      \"gaps\": [\n        \"Single lab, localization by IFA without functional follow-up or reciprocal validation\",\n        \"No mechanistic pathway placement or defined molecular function beyond antigen recognition\",\n        \"Mechanism of apical targeting and secretion of a ribosomal protein is unresolved\"\n      ],\n      \"attribution\": [\n        {\"species\": \"Toxoplasma gondii\", \"strain\": \"RH\"}\n      ]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"The molecular function of TgRPS2 beyond its identity as a secreted antigen, and how a ribosomal protein comes to localize apically and enter host circulation, remain unknown.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Low\",\n      \"gaps\": [\n        \"No functional characterization or knockout phenotype\",\n        \"No binding partners or pathway placement established\",\n        \"Secretion mechanism uncharacterized\"\n      ],\n      \"attribution\": [\n        {\"species\": \"Toxoplasma gondii\", \"strain\": \"RH\"}\n      ]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [],\n    \"localization\": [\n      {\"term_id\": \"apical end of tachyzoite\", \"supporting_discovery_ids\": [0], \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"RH\"}]},\n      {\"term_id\": \"secreted / circulating antigen (serum)\", \"supporting_discovery_ids\": [0], \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"RH\"}]}\n    ],\n    \"pathway\": [],\n    \"complexes\": [],\n    \"partners\": [],\n    \"other_free_text\": [\n      \"Identified as a circulating antigen detectable in serum of T. gondii RH-infected mice [#0]\"\n    ]\n  },\n  \"strain_conflicts\": []\n}","audit_flag":null,"strains":[{"strain":"ME49","gene_id":"TGME49_305520","name":"RPS2","product":"ribosomal protein RPS2","uniprot_acc":"A0A125YUG3","chromosome":"TGME49_chrIX","start_pos":5449444},{"strain":"GT1","gene_id":"TGGT1_305520","name":null,"product":"ribosomal protein RPS2","uniprot_acc":null,"chromosome":"TGGT1_chrIX","start_pos":5229307},{"strain":"RH88","gene_id":"TGRH88_017180","name":null,"product":"ribosomal protein RPS2","uniprot_acc":null,"chromosome":"CM023090","start_pos":5571701},{"strain":"VEG","gene_id":"TGVEG_305520","name":null,"product":"ribosomal protein RPS2","uniprot_acc":"B9PZF2","chromosome":"TGVEG_chrIX","start_pos":5487008}]}