{"gene":"PF3D7_0322100","run_date":"2026-09-07T10:55:51","timeline":{"discoveries":[{"year":2001,"finding":"PF3D7_0322100 (Prt1) encodes an RNA 5'-triphosphatase that is a member of the fungal/viral family of metal-dependent phosphohydrolases, structurally and mechanistically distinct from the cysteine-phosphatase-type RNA triphosphatases found in metazoans and plants. It functions as a separate enzyme from the RNA guanylyltransferase (Pgt1) in the P. falciparum mRNA capping apparatus.","method":"Biochemical characterization and phylogenetic/sequence analysis of expressed P. falciparum Prt1 protein, distinguishing its metal-dependent phosphohydrolase mechanism from metazoan cysteine-phosphatase triphosphatases","journal":"Proceedings of the National Academy of Sciences of the United States of America","confidence":"Medium","confidence_rationale":"Tier 1–2 / Weak — enzymatic activity and mechanistic classification established in a single study; abstract does not detail full mutagenesis or structure, limiting to moderate-weak evidence","pmids":["11248030"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2024,"finding":"PF3D7_0322100 (Prt1/PfPRT1) is essential for P. falciparum viability; its essentiality was confirmed experimentally, and it was shown to be amenable to recombinant purification and enzymatic activity assessment, confirming its role as the metal-dependent mRNA 5'-triphosphatase catalyzing the first step of nuclear mRNA capping.","method":"Genetic essentiality validation (loss-of-function), recombinant protein purification, enzymatic activity assay, and target engagement assessment","journal":"International journal for parasitology. Drugs and drug resistance","confidence":"Medium","confidence_rationale":"Tier 2 / Weak — essentiality confirmed by genetic tools and enzymatic activity demonstrated in a single lab study; no structural or mutagenesis data described in abstract","pmids":["38810336"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]}],"current_model":"PF3D7_0322100 (Prt1) is an essential P. falciparum RNA 5'-triphosphatase of the metal-dependent phosphohydrolase family that catalyzes the first step of nuclear mRNA capping, functioning as a separate enzyme from the RNA guanylyltransferase subunit (Pgt1) and operating by a mechanism structurally unrelated to the cysteine-phosphatase-type triphosphatases of metazoans and plants."},"narrative":{"mechanistic_narrative":"PF3D7_0322100 (Prt1) is an essential Plasmodium falciparum RNA 5'-triphosphatase that catalyzes the first step of nuclear mRNA capping [PMID:11248030, PMID:38810336]. It belongs to the fungal/viral family of metal-dependent phosphohydrolases and is structurally and mechanistically distinct from the cysteine-phosphatase-type RNA triphosphatases of metazoans and plants, and it operates as a separate enzyme from the RNA guanylyltransferase Pgt1 within the parasite's capping apparatus [PMID:11248030]. Genetic loss-of-function analysis established that Prt1 is required for P. falciparum viability, and the recombinant protein is amenable to purification and enzymatic activity assessment consistent with its assigned triphosphatase role [PMID:38810336]. Beyond its enzymatic classification, essentiality, and separation from Pgt1, no structural model or catalytic-residue mutagenesis of Prt1 has been characterized in the available corpus.","teleology":[{"year":2001,"claim":"Establishing how P. falciparum removes the 5'-gamma-phosphate of nascent mRNA answered which enzyme catalyzes the first capping step and revealed a mechanism distinct from the host, defining a candidate drug target class.","evidence":"Biochemical characterization and phylogenetic/sequence analysis of expressed P. falciparum Prt1 protein","pmids":["11248030"],"confidence":"Medium","gaps":["No structural model or catalytic-residue mutagenesis reported","Physical/functional coupling between Prt1 and Pgt1 not resolved","Metal-ion requirement not defined at the mechanistic level in the abstract"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2024,"claim":"Testing whether Prt1 is dispensable answered its value as a target: genetic loss-of-function showed the enzyme is essential for parasite viability, and recombinant activity assays confirmed its triphosphatase function.","evidence":"Genetic essentiality validation, recombinant protein purification, enzymatic activity assay, and target engagement assessment","pmids":["38810336"],"confidence":"Medium","gaps":["No structural or mutagenesis data described","Target-engagement assay not tied to a validated inhibitor mechanism in the abstract","Stage-specificity of essentiality not defined"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":null,"claim":"The structural basis of Prt1 catalysis, its metal coordination, and how it functionally coordinates with the guanylyltransferase Pgt1 during capping remain unresolved.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No crystal or cryo-EM structure of Prt1","Catalytic and metal-binding residues not mapped by mutagenesis","Mechanism of coordination with Pgt1 in the capping apparatus unknown"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]}],"mechanism_profile":{"molecular_activity":[],"localization":[],"pathway":[],"complexes":["P. falciparum mRNA capping apparatus (functions as separate enzyme from RNA guanylyltransferase Pgt1)"],"partners":["PGT1 (RNA GUANYLYLTRANSFERASE; DISTINCT SUBUNIT OF THE CAPPING APPARATUS)"],"other_free_text":["Member of the fungal/viral family of metal-dependent phosphohydrolases, mechanistically distinct from metazoan/plant cysteine-phosphatase-type RNA triphosphatases [#0]","Essential for P. falciparum viability [#1]","Amenable to recombinant purification and enzymatic activity assessment [#1]"]}},"prefetch_data":{},"corpus_meta":[{"pmid":"11248030","id":"PMC_11248030","title":"A yeast-like mRNA capping apparatus in Plasmodium falciparum.","date":"2001","source":"Proceedings of the National Academy of Sciences of the United States of America","url":"https://pubmed.ncbi.nlm.nih.gov/11248030","citation_count":40,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["Prt1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"38810336","id":"PMC_38810336","title":"Plasmodium RNA triphosphatase validation as antimalarial target.","date":"2024","source":"International journal for parasitology. Drugs and drug resistance","url":"https://pubmed.ncbi.nlm.nih.gov/38810336","citation_count":0,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["PfPrt1","PvPrt1"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":3597,"output_tokens":756,"usd":0.011066,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":5416,"output_tokens":1598,"usd":0.033515,"stage2_stop_reason":"end_turn"},"total_usd":0.044581,"stage1_batch_id":"msgbatch_01DbiymDmubkPpYvdbAu5a7V","stage2_batch_id":"msgbatch_012TbrWvMRH129T7PQ4SmvrJ","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2001,\n      \"finding\": \"PF3D7_0322100 (Prt1) encodes an RNA 5'-triphosphatase that is a member of the fungal/viral family of metal-dependent phosphohydrolases, structurally and mechanistically distinct from the cysteine-phosphatase-type RNA triphosphatases found in metazoans and plants. It functions as a separate enzyme from the RNA guanylyltransferase (Pgt1) in the P. falciparum mRNA capping apparatus.\",\n      \"method\": \"Biochemical characterization and phylogenetic/sequence analysis of expressed P. falciparum Prt1 protein, distinguishing its metal-dependent phosphohydrolase mechanism from metazoan cysteine-phosphatase triphosphatases\",\n      \"journal\": \"Proceedings of the National Academy of Sciences of the United States of America\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1–2 / Weak — enzymatic activity and mechanistic classification established in a single study; abstract does not detail full mutagenesis or structure, limiting to moderate-weak evidence\",\n      \"pmids\": [\"11248030\"],\n      \"is_preprint\": false,\n      \"attribution\": [\n        {\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}\n      ]\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"PF3D7_0322100 (Prt1/PfPRT1) is essential for P. falciparum viability; its essentiality was confirmed experimentally, and it was shown to be amenable to recombinant purification and enzymatic activity assessment, confirming its role as the metal-dependent mRNA 5'-triphosphatase catalyzing the first step of nuclear mRNA capping.\",\n      \"method\": \"Genetic essentiality validation (loss-of-function), recombinant protein purification, enzymatic activity assay, and target engagement assessment\",\n      \"journal\": \"International journal for parasitology. Drugs and drug resistance\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Weak — essentiality confirmed by genetic tools and enzymatic activity demonstrated in a single lab study; no structural or mutagenesis data described in abstract\",\n      \"pmids\": [\"38810336\"],\n      \"is_preprint\": false,\n      \"attribution\": [\n        {\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}\n      ]\n    }\n  ],\n  \"current_model\": \"PF3D7_0322100 (Prt1) is an essential P. falciparum RNA 5'-triphosphatase of the metal-dependent phosphohydrolase family that catalyzes the first step of nuclear mRNA capping, functioning as a separate enzyme from the RNA guanylyltransferase subunit (Pgt1) and operating by a mechanism structurally unrelated to the cysteine-phosphatase-type triphosphatases of metazoans and plants.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"PF3D7_0322100 (Prt1) is an essential Plasmodium falciparum RNA 5'-triphosphatase that catalyzes the first step of nuclear mRNA capping [#0, #1]. It belongs to the fungal/viral family of metal-dependent phosphohydrolases and is structurally and mechanistically distinct from the cysteine-phosphatase-type RNA triphosphatases of metazoans and plants, and it operates as a separate enzyme from the RNA guanylyltransferase Pgt1 within the parasite's capping apparatus [#0]. Genetic loss-of-function analysis established that Prt1 is required for P. falciparum viability, and the recombinant protein is amenable to purification and enzymatic activity assessment consistent with its assigned triphosphatase role [#1]. Beyond its enzymatic classification, essentiality, and separation from Pgt1, no structural model or catalytic-residue mutagenesis of Prt1 has been characterized in the available corpus.\",\n  \"teleology\": [\n    {\n      \"year\": 2001,\n      \"claim\": \"Establishing how P. falciparum removes the 5'-gamma-phosphate of nascent mRNA answered which enzyme catalyzes the first capping step and revealed a mechanism distinct from the host, defining a candidate drug target class.\",\n      \"evidence\": \"Biochemical characterization and phylogenetic/sequence analysis of expressed P. falciparum Prt1 protein\",\n      \"pmids\": [\"11248030\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"No structural model or catalytic-residue mutagenesis reported\",\n        \"Physical/functional coupling between Prt1 and Pgt1 not resolved\",\n        \"Metal-ion requirement not defined at the mechanistic level in the abstract\"\n      ],\n      \"attribution\": [\n        {\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}\n      ]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Testing whether Prt1 is dispensable answered its value as a target: genetic loss-of-function showed the enzyme is essential for parasite viability, and recombinant activity assays confirmed its triphosphatase function.\",\n      \"evidence\": \"Genetic essentiality validation, recombinant protein purification, enzymatic activity assay, and target engagement assessment\",\n      \"pmids\": [\"38810336\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"No structural or mutagenesis data described\",\n        \"Target-engagement assay not tied to a validated inhibitor mechanism in the abstract\",\n        \"Stage-specificity of essentiality not defined\"\n      ],\n      \"attribution\": [\n        {\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}\n      ]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"The structural basis of Prt1 catalysis, its metal coordination, and how it functionally coordinates with the guanylyltransferase Pgt1 during capping remain unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"No crystal or cryo-EM structure of Prt1\",\n        \"Catalytic and metal-binding residues not mapped by mutagenesis\",\n        \"Mechanism of coordination with Pgt1 in the capping apparatus unknown\"\n      ],\n      \"attribution\": [\n        {\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}\n      ]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0004651\", \"supporting_discovery_ids\": [0, 1]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005634\", \"supporting_discovery_ids\": [0]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"GO:0006370\", \"supporting_discovery_ids\": [0, 1]}\n    ],\n    \"complexes\": [\n      \"P. falciparum mRNA capping apparatus (functions as separate enzyme from RNA guanylyltransferase Pgt1)\"\n    ],\n    \"partners\": [\n      \"Pgt1 (RNA guanylyltransferase; distinct subunit of the capping apparatus)\"\n    ],\n    \"other_free_text\": [\n      \"Member of the fungal/viral family of metal-dependent phosphohydrolases, mechanistically distinct from metazoan/plant cysteine-phosphatase-type RNA triphosphatases [#0]\",\n      \"Essential for P. falciparum viability [#1]\",\n      \"Amenable to recombinant purification and enzymatic activity assessment [#1]\"\n    ]\n  }\n}","audit_flag":null,"strains":[{"strain":"Pf3D7","gene_id":"PF3D7_0322100","name":null,"product":"mRNA-capping enzyme subunit beta","uniprot_acc":null,"chromosome":null,"start_pos":null},{"strain":"PbANKA","gene_id":"PBANKA_1216400","name":null,"product":"mRNA-capping enzyme subunit beta, putative","uniprot_acc":null,"chromosome":null,"start_pos":null},{"strain":"PkH","gene_id":"PKNH_0818700","name":null,"product":"mRNA-capping enzyme subunit beta, putative","uniprot_acc":null,"chromosome":null,"start_pos":null}],"gene_symbol":"Prt1","evaluation":null}