{"gene":"TG_312570","gene_symbol":"MAPKL1","run_date":"2026-09-10T21:09:19","timeline":{"discoveries":[{"year":2006,"finding":"Toxoplasma gondii encodes two distinct MAPK genes (tgMAPK1 and tgMAPK2) representing novel protozoan MAPK subfamilies (pzMAPKl/pzMAPK3 and pzMAPK2); tgMAPK1 (MAPKL1) is a stress-response MAPK-related gene belonging to a protozoan-specific subfamily distinct from ERK, JNK, and p38 families, as determined by phylogenetic and cloning analysis.","method":"Gene cloning, phylogenetic analysis of protozoan and metazoan MAPK sequences","journal":"Journal of molecular evolution","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — cloning and phylogenetic characterization, single lab, foundational identification of the gene","pmids":["17160647"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2002,"finding":"Pyridinylimidazole p38 MAPK inhibitors (SB203580, SB202190) block intracellular T. gondii replication through direct action on the parasite rather than the host cell; selective host p38 MAPK inhibition via recombinant adenovirus had little effect, drug-resistant mutant tachyzoites were generated, and treated parasites developed abnormal morphology indicating defective division, implicating a parasite-encoded MAPK homologue (later identified as TgMAPKL-1) as the drug target.","method":"Pharmacological inhibition, adenoviral dominant-negative host kinase, generation of drug-resistant mutants, morphological analysis","journal":"International journal for parasitology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — multiple orthogonal methods in a single lab; drug target identity inferred but not directly proven at this stage","pmids":["12076626"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2007,"finding":"Pyridinylimidazole p38 MAPK inhibitors treat T. gondii infection in vivo and preliminary studies implicate a T. gondii MAPK homologue (TgMAPKL-1) as the target of drug action, consistent with the parasite encoding an endogenous MAPK whose inhibition is anti-parasitic.","method":"In vivo mouse infection model, pharmacological inhibition, preliminary target identification","journal":"Antimicrobial agents and chemotherapy","confidence":"Low","confidence_rationale":"Tier 3 / Weak — in vivo pharmacology with preliminary mechanistic inference, target identity not directly confirmed","pmids":["17923491"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2014,"finding":"A mutation in the gatekeeper residue Ser191 of TgMAPKL-1 (S191A) confers sensitivity to the bumped kinase inhibitor 1NM-PP1, which was originally selected as a resistance mutation. Inhibition of TgMAPKL-1 by 1NM-PP1 blocks cell cycle progression after DNA duplication, causing enlarged parasites with multiple daughter cell scaffolds and incomplete cytokinesis, demonstrating that TgMAPKL-1 is required for completion of endodyogeny.","method":"Site-directed mutagenesis of gatekeeper residue, bumped kinase inhibitor treatment, cell cycle analysis, morphological analysis","journal":"International journal for parasitology. Drugs and drug resistance","confidence":"High","confidence_rationale":"Tier 1-2 / Moderate — active-site mutagenesis combined with pharmacological inhibition and detailed cell cycle/morphological phenotyping in a single focused study","pmids":["25941623"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":"RH"}]},{"year":2020,"finding":"MAPKL1 depletion causes a distinct centrosome duplication failure phenotype in T. gondii; the failure in centrosome duplication caused by loss of MAPKL1 is distinguishable from the centrosome duplication phenotype caused by loss of MAPK2, indicating MAPKL1 and MAPK2 regulate distinct steps of centrosome duplication.","method":"Auxin-inducible degron (AID) system for conditional protein depletion, fluorescence microscopy, comparative phenotypic analysis","journal":"mBio","confidence":"High","confidence_rationale":"Tier 2 / Moderate — AID-based conditional depletion with rigorous comparative cell biological analysis distinguishing two kinase phenotypes","pmids":["33173004"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2025,"finding":"A forward genetic screen using chemical mutagenesis and BKI-1748 selection identified single nucleotide changes in the ATP-binding site of TgMAPKL1 (including Leu162Gln) conferring 2–6-fold resistance; introducing this mutation into wild-type parasites confirmed MAPKL1 as a direct target of BKI-1748. Combining TgMAPKL1 and TgCDPK1 resistance mutations produced up to 157-fold resistance, demonstrating that BKIs act on both kinases simultaneously.","method":"Forward genetic screen, whole-genome sequencing, site-directed mutagenesis (Leu162Gln knock-in), pharmacological resistance assays","journal":"ACS infectious diseases","confidence":"High","confidence_rationale":"Tier 1-2 / Strong — forward genetics, genome sequencing, and reciprocal mutagenesis all converge on MAPKL1 as a BKI target; multiple orthogonal methods in a focused mechanistic study","pmids":["40407244"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2025,"finding":"Enzymatic assays and structural/modeling studies demonstrate that imidazole compounds (R)-RY-1-165 and (R)-RY-1-185 bind and inhibit TgMAPKL-1 in T. gondii, alongside TgPKG, TgCDPK1, and TgCDPK4, identifying TgMAPKL-1 as part of the multi-target mechanism of action of this scaffold.","method":"Enzymatic assays, structural modeling, mutant parasite studies (gatekeeper substitutions)","journal":"ACS infectious diseases","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — enzymatic assays and modeling support target engagement, but TgMAPKL-1 is one of several targets identified and direct structural confirmation is partial","pmids":["40339062"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2022,"finding":"Review consolidating that apicomplexan MAPKL1 has been implicated in centrosome duplication regulation in Toxoplasma, and that canonical MAPK kinase cascade regulation is absent in apicomplexans, meaning MAPKL1 must be regulated by a distinct, non-canonical mechanism.","method":"Review/synthesis of prior experimental findings","journal":"PLoS pathogens","confidence":"Low","confidence_rationale":"Tier 4 / Weak — review paper synthesizing previously published experimental data; no new experiments on MAPKL1","pmids":["36227859"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2026,"finding":"BKI-1748, which targets both TgCDPK1 and TgMAPKL-1, confers significant protection against congenital toxoplasmosis in a pregnant sheep model when administered after IgM seroconversion, demonstrating that dual inhibition of these kinases is effective in a clinically relevant large-animal model.","method":"In vivo sheep infection model, oral BKI-1748 treatment, serology, parasite detection in offspring","journal":"Frontiers in cellular and infection microbiology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — in vivo therapeutic efficacy in large animal model; mechanistic attribution to MAPKL1 is based on prior genetic data, not re-confirmed here","pmids":["42125495"],"is_preprint":false,"attribution":[{"species":"Toxoplasma gondii","strain":"TgShSp1"}]}],"current_model":"TgMAPKL1 is a Toxoplasma gondii-specific MAPK-like serine/threonine kinase that localizes to the centrosome, where it restricts centrosome core duplication to once per cell cycle and is required for the completion of endodyogeny (daughter cell budding and cytokinesis); it is a direct molecular target of bumped kinase inhibitors (BKIs) through its ATP-binding pocket, and its inhibition arrests the parasite cell cycle after DNA duplication, causing incomplete cytokinesis and parasite death."},"narrative":{"mechanistic_narrative":"TgMAPKL1 (TgMAPK1) is a Toxoplasma gondii serine/threonine protein kinase that belongs to a protozoan-specific MAPK-related subfamily distinct from the metazoan ERK, JNK, and p38 families [PMID:17160647]. It localizes to the centrosome, where loss of function produces aberrant centrosome duplication [PMID:33173004], a phenotype distinguishable from that caused by loss of TgMAPK2, indicating the two kinases govern separate steps of centrosome duplication [PMID:33173004]. Inhibition of the kinase arrests the cell cycle after DNA duplication, generating enlarged parasites with multiple daughter scaffolds and incomplete cytokinesis, establishing that TgMAPKL1 is required for completion of endodyogeny [PMID:25941623]. Its catalytic activity depends on an ATP-binding pocket accessible through the gatekeeper residue Ser191, and gatekeeper or ATP-site mutations (S191A, Leu162Gln) modulate sensitivity to bumped kinase inhibitors, confirming TgMAPKL1 as a direct BKI target alongside TgCDPK1 [PMID:25941623, PMID:40407244]. Enzymatic assays and structural/modeling studies demonstrate that imidazole compounds (R)-RY-1-165 and (R)-RY-1-185 bind and inhibit TgMAPKL-1 in T. gondii, identifying TgMAPKL-1 as part of the multi-target mechanism of action of this scaffold [PMID:40339062]. BKI-1748, which targets both TgCDPK1 and TgMAPKL-1, confers significant protection against congenital toxoplasmosis in a pregnant sheep model when administered after IgM seroconversion, demonstrating that dual inhibition of these kinases is effective in a clinically relevant large-animal model [PMID:42125495]. Because apicomplexans lack the canonical MAPK kinase cascade, TgMAPKL1 must be activated by a non-canonical mechanism that has not been characterized in the available corpus [PMID:36227859].","teleology":[{"year":2002,"claim":"Before any parasite MAPK was cloned, it was unknown whether p38 inhibitors blocked T. gondii replication through the host or the parasite; this work showed the drug acts directly on a parasite-encoded kinase.","evidence":"Pharmacological inhibition with SB203580/SB202190, adenoviral dominant-negative host p38, and drug-resistant mutant tachyzoites in T. gondii","pmids":["12076626"],"confidence":"Medium","gaps":["Target kinase identity inferred, not molecularly proven","No direct enzymatic assay of the parasite kinase"],"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2006,"claim":"The molecular identity of the parasite MAPK was defined by cloning tgMAPK1/MAPKL1 and placing it in a protozoan-specific subfamily distinct from ERK, JNK, and p38.","evidence":"Gene cloning and phylogenetic analysis of protozoan and metazoan MAPK sequences in T. gondii","pmids":["17160647"],"confidence":"Medium","gaps":["Cellular function not addressed","No localization or loss-of-function data"],"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2007,"claim":"Extending the pharmacology in vivo, p38-class inhibitors were shown to treat infection in mice with preliminary attribution to the parasite MAPK homologue.","evidence":"In vivo mouse infection model with pharmacological inhibition and preliminary target inference","pmids":["17923491"],"confidence":"Low","gaps":["Target identity not directly confirmed","No genetic validation of the kinase as the effector"],"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2014,"claim":"It was unknown what step of the cell cycle the kinase controls; gatekeeper engineering plus bumped kinase inhibition pinpointed a post-DNA-duplication requirement for completing daughter cell budding.","evidence":"Gatekeeper Ser191 mutagenesis (S191A), 1NM-PP1 treatment, cell cycle and morphological analysis in T. gondii RH","pmids":["25941623"],"confidence":"High","gaps":["Direct substrates not identified","Mechanism linking kinase activity to cytokinesis unresolved"],"attribution":[{"species":"Toxoplasma gondii","strain":"RH"}]},{"year":2020,"claim":"To resolve whether the two parasite MAPK-related kinases act redundantly, conditional depletion showed MAPKL1 and MAPK2 produce distinct centrosome duplication failure phenotypes, defining separate steps.","evidence":"Auxin-inducible degron depletion with comparative fluorescence microscopy in T. gondii","pmids":["33173004"],"confidence":"High","gaps":["Molecular basis of the step specificity not defined","No epistatic or biochemical relationship between MAPKL1 and MAPK2 established"],"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2025,"claim":"Forward genetics and reciprocal mutagenesis confirmed MAPKL1 as a direct BKI target and showed BKIs simultaneously engage both MAPKL1 and CDPK1.","evidence":"Chemical mutagenesis/BKI-1748 selection, whole-genome sequencing, Leu162Gln knock-in, and enzymatic/structural modeling with gatekeeper substitutions in T. gondii","pmids":["40407244","40339062"],"confidence":"High","gaps":["No high-resolution structure of the inhibited kinase","Native regulatory phosphorylation events unmapped"],"attribution":[{"species":"Toxoplasma gondii","strain":""}]},{"year":2026,"claim":"Dual inhibition of MAPKL1 and CDPK1 by BKI-1748 was shown to be therapeutically effective against congenital toxoplasmosis in a large-animal model.","evidence":"Pregnant sheep infection model with oral BKI-1748, serology, and parasite detection in offspring in T. gondii TgShSp1","pmids":["42125495"],"confidence":"Medium","gaps":["Efficacy is attributed to dual kinase inhibition but not deconvoluted to MAPKL1 alone","Mechanistic contribution of MAPKL1 not re-tested in this model"],"attribution":[{"species":"Toxoplasma gondii","strain":"TgShSp1"}]}],"mechanism_profile":{"molecular_activity":[],"localization":[],"pathway":[],"complexes":[],"partners":[],"other_free_text":["Protozoan-specific MAPK-related subfamily distinct from ERK/JNK/p38 [#0].","Gatekeeper residue Ser191 and ATP-site residue Leu162 govern bumped kinase inhibitor sensitivity/resistance [#4, #6].","Direct molecular target of bumped kinase inhibitors (1NM-PP1, BKI-1748, (R)-RY-1-165/-185), co-targeted with TgCDPK1 [#4, #6, #7].","Acts on a step of centrosome duplication distinct from that regulated by TgMAPK2 [#5].","Regulated by a non-canonical mechanism, as apicomplexans lack the canonical MAPK kinase cascade [#8]."]},"strain_conflicts":[]},"prefetch_data":{},"corpus_meta":[{"pmid":"24316259","id":"PMC_24316259","title":"Artemisinins: pharmacological actions beyond anti-malarial.","date":"2013","source":"Pharmacology & 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tgMAPK1 (MAPKL1) is a stress-response MAPK-related gene belonging to a protozoan-specific subfamily distinct from ERK, JNK, and p38 families, as determined by phylogenetic and cloning analysis.\",\n      \"method\": \"Gene cloning, phylogenetic analysis of protozoan and metazoan MAPK sequences\",\n      \"journal\": \"Journal of molecular evolution\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — cloning and phylogenetic characterization, single lab, foundational identification of the gene\",\n      \"pmids\": [\"17160647\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2002,\n      \"finding\": \"Pyridinylimidazole p38 MAPK inhibitors (SB203580, SB202190) block intracellular T. gondii replication through direct action on the parasite rather than the host cell; selective host p38 MAPK inhibition via recombinant adenovirus had little effect, drug-resistant mutant tachyzoites were generated, and treated parasites developed abnormal morphology indicating defective division, implicating a parasite-encoded MAPK homologue (later identified as TgMAPKL-1) as the drug target.\",\n      \"method\": \"Pharmacological inhibition, adenoviral dominant-negative host kinase, generation of drug-resistant mutants, morphological analysis\",\n      \"journal\": \"International journal for parasitology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — multiple orthogonal methods in a single lab; drug target identity inferred but not directly proven at this stage\",\n      \"pmids\": [\"12076626\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2007,\n      \"finding\": \"Pyridinylimidazole p38 MAPK inhibitors treat T. gondii infection in vivo and preliminary studies implicate a T. gondii MAPK homologue (TgMAPKL-1) as the target of drug action, consistent with the parasite encoding an endogenous MAPK whose inhibition is anti-parasitic.\",\n      \"method\": \"In vivo mouse infection model, pharmacological inhibition, preliminary target identification\",\n      \"journal\": \"Antimicrobial agents and chemotherapy\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — in vivo pharmacology with preliminary mechanistic inference, target identity not directly confirmed\",\n      \"pmids\": [\"17923491\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"A key serine/threonine kinase distantly related to the MAPK family (MAPKL1) localizes to the centrosome in T. gondii, where it restricts centrosome core duplication to once per cell cycle and ensures proper formation of new daughter parasites; loss of MAPKL1 function leads to aberrant centrosome duplication.\",\n      \"method\": \"Fluorescence microscopy (localization), genetic analysis using temperature-sensitive mutant, cell biological phenotypic analysis\",\n      \"journal\": \"PLoS biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — direct localization by imaging combined with genetic loss-of-function analysis showing specific centrosome duplication defect, rigorous cell cycle phenotyping\",\n      \"pmids\": [\"25734885\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"A mutation in the gatekeeper residue Ser191 of TgMAPKL-1 (S191A) confers sensitivity to the bumped kinase inhibitor 1NM-PP1, which was originally selected as a resistance mutation. Inhibition of TgMAPKL-1 by 1NM-PP1 blocks cell cycle progression after DNA duplication, causing enlarged parasites with multiple daughter cell scaffolds and incomplete cytokinesis, demonstrating that TgMAPKL-1 is required for completion of endodyogeny.\",\n      \"method\": \"Site-directed mutagenesis of gatekeeper residue, bumped kinase inhibitor treatment, cell cycle analysis, morphological analysis\",\n      \"journal\": \"International journal for parasitology. Drugs and drug resistance\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 / Moderate — active-site mutagenesis combined with pharmacological inhibition and detailed cell cycle/morphological phenotyping in a single focused study\",\n      \"pmids\": [\"25941623\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"RH\"}]\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"MAPKL1 depletion causes a distinct centrosome duplication failure phenotype in T. gondii; the failure in centrosome duplication caused by loss of MAPKL1 is distinguishable from the centrosome duplication phenotype caused by loss of MAPK2, indicating MAPKL1 and MAPK2 regulate distinct steps of centrosome duplication.\",\n      \"method\": \"Auxin-inducible degron (AID) system for conditional protein depletion, fluorescence microscopy, comparative phenotypic analysis\",\n      \"journal\": \"mBio\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — AID-based conditional depletion with rigorous comparative cell biological analysis distinguishing two kinase phenotypes\",\n      \"pmids\": [\"33173004\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"A forward genetic screen using chemical mutagenesis and BKI-1748 selection identified single nucleotide changes in the ATP-binding site of TgMAPKL1 (including Leu162Gln) conferring 2–6-fold resistance; introducing this mutation into wild-type parasites confirmed MAPKL1 as a direct target of BKI-1748. Combining TgMAPKL1 and TgCDPK1 resistance mutations produced up to 157-fold resistance, demonstrating that BKIs act on both kinases simultaneously.\",\n      \"method\": \"Forward genetic screen, whole-genome sequencing, site-directed mutagenesis (Leu162Gln knock-in), pharmacological resistance assays\",\n      \"journal\": \"ACS infectious diseases\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 / Strong — forward genetics, genome sequencing, and reciprocal mutagenesis all converge on MAPKL1 as a BKI target; multiple orthogonal methods in a focused mechanistic study\",\n      \"pmids\": [\"40407244\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"Enzymatic assays and structural/modeling studies demonstrate that imidazole compounds (R)-RY-1-165 and (R)-RY-1-185 bind and inhibit TgMAPKL-1 in T. gondii, alongside TgPKG, TgCDPK1, and TgCDPK4, identifying TgMAPKL-1 as part of the multi-target mechanism of action of this scaffold.\",\n      \"method\": \"Enzymatic assays, structural modeling, mutant parasite studies (gatekeeper substitutions)\",\n      \"journal\": \"ACS infectious diseases\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — enzymatic assays and modeling support target engagement, but TgMAPKL-1 is one of several targets identified and direct structural confirmation is partial\",\n      \"pmids\": [\"40339062\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"Review consolidating that apicomplexan MAPKL1 has been implicated in centrosome duplication regulation in Toxoplasma, and that canonical MAPK kinase cascade regulation is absent in apicomplexans, meaning MAPKL1 must be regulated by a distinct, non-canonical mechanism.\",\n      \"method\": \"Review/synthesis of prior experimental findings\",\n      \"journal\": \"PLoS pathogens\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 4 / Weak — review paper synthesizing previously published experimental data; no new experiments on MAPKL1\",\n      \"pmids\": [\"36227859\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2026,\n      \"finding\": \"BKI-1748, which targets both TgCDPK1 and TgMAPKL-1, confers significant protection against congenital toxoplasmosis in a pregnant sheep model when administered after IgM seroconversion, demonstrating that dual inhibition of these kinases is effective in a clinically relevant large-animal model.\",\n      \"method\": \"In vivo sheep infection model, oral BKI-1748 treatment, serology, parasite detection in offspring\",\n      \"journal\": \"Frontiers in cellular and infection microbiology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — in vivo therapeutic efficacy in large animal model; mechanistic attribution to MAPKL1 is based on prior genetic data, not re-confirmed here\",\n      \"pmids\": [\"42125495\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"TgShSp1\"}]\n    }\n  ],\n  \"current_model\": \"TgMAPKL1 is a Toxoplasma gondii-specific MAPK-like serine/threonine kinase that localizes to the centrosome, where it restricts centrosome core duplication to once per cell cycle and is required for the completion of endodyogeny (daughter cell budding and cytokinesis); it is a direct molecular target of bumped kinase inhibitors (BKIs) through its ATP-binding pocket, and its inhibition arrests the parasite cell cycle after DNA duplication, causing incomplete cytokinesis and parasite death.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"TgMAPKL1 (TgMAPK1) is a Toxoplasma gondii serine/threonine protein kinase that belongs to a protozoan-specific MAPK-related subfamily distinct from the metazoan ERK, JNK, and p38 families [#0], and it functions as a centrosome-associated regulator of parasite cell division [#3]. It localizes to the centrosome, where it restricts centrosome core duplication to once per cell cycle and ensures the proper formation of daughter parasites; loss of function produces aberrant centrosome duplication [#3], a phenotype distinguishable from that caused by loss of TgMAPK2, indicating the two kinases govern separate steps of centrosome duplication [#5]. Inhibition of the kinase arrests the cell cycle after DNA duplication, generating enlarged parasites with multiple daughter scaffolds and incomplete cytokinesis, establishing that TgMAPKL1 is required for completion of endodyogeny [#4]. Its catalytic activity depends on an ATP-binding pocket accessible through the gatekeeper residue Ser191, and gatekeeper or ATP-site mutations (S191A, Leu162Gln) modulate sensitivity to bumped kinase inhibitors, confirming TgMAPKL1 as a direct BKI target alongside TgCDPK1 [#4, #6]. Because apicomplexans lack the canonical MAPK kinase cascade, TgMAPKL1 must be activated by a non-canonical mechanism that has not been characterized in the available corpus [#8].\"\n  ,\n  \"teleology\": [\n    {\n      \"year\": 2002,\n      \"claim\": \"Before any parasite MAPK was cloned, it was unknown whether p38 inhibitors blocked T. gondii replication through the host or the parasite; this work showed the drug acts directly on a parasite-encoded kinase.\",\n      \"evidence\": \"Pharmacological inhibition with SB203580/SB202190, adenoviral dominant-negative host p38, and drug-resistant mutant tachyzoites in T. gondii\",\n      \"pmids\": [\"12076626\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Target kinase identity inferred, not molecularly proven\", \"No direct enzymatic assay of the parasite kinase\"],\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2006,\n      \"claim\": \"The molecular identity of the parasite MAPK was defined by cloning tgMAPK1/MAPKL1 and placing it in a protozoan-specific subfamily distinct from ERK, JNK, and p38.\",\n      \"evidence\": \"Gene cloning and phylogenetic analysis of protozoan and metazoan MAPK sequences in T. gondii\",\n      \"pmids\": [\"17160647\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Cellular function not addressed\", \"No localization or loss-of-function data\"],\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2007,\n      \"claim\": \"Extending the pharmacology in vivo, p38-class inhibitors were shown to treat infection in mice with preliminary attribution to the parasite MAPK homologue.\",\n      \"evidence\": \"In vivo mouse infection model with pharmacological inhibition and preliminary target inference\",\n      \"pmids\": [\"17923491\"],\n      \"confidence\": \"Low\",\n      \"gaps\": [\"Target identity not directly confirmed\", \"No genetic validation of the kinase as the effector\"],\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2014,\n      \"claim\": \"It was unknown what step of the cell cycle the kinase controls; gatekeeper engineering plus bumped kinase inhibition pinpointed a post-DNA-duplication requirement for completing daughter cell budding.\",\n      \"evidence\": \"Gatekeeper Ser191 mutagenesis (S191A), 1NM-PP1 treatment, cell cycle and morphological analysis in T. gondii RH\",\n      \"pmids\": [\"25941623\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Direct substrates not identified\", \"Mechanism linking kinase activity to cytokinesis unresolved\"],\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"RH\"}]\n    },\n    {\n      \"year\": 2015,\n      \"claim\": \"The subcellular basis of its function was established: MAPKL1 localizes to the centrosome and restricts centrosome core duplication to once per cell cycle.\",\n      \"evidence\": \"Fluorescence localization and temperature-sensitive mutant genetic loss-of-function phenotyping in T. gondii\",\n      \"pmids\": [\"25734885\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"No identified centrosomal substrate or interacting partner\", \"Upstream regulator unknown\"],\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"To resolve whether the two parasite MAPK-related kinases act redundantly, conditional depletion showed MAPKL1 and MAPK2 produce distinct centrosome duplication failure phenotypes, defining separate steps.\",\n      \"evidence\": \"Auxin-inducible degron depletion with comparative fluorescence microscopy in T. gondii\",\n      \"pmids\": [\"33173004\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Molecular basis of the step specificity not defined\", \"No epistatic or biochemical relationship between MAPKL1 and MAPK2 established\"],\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Forward genetics and reciprocal mutagenesis confirmed MAPKL1 as a direct BKI target and showed BKIs simultaneously engage both MAPKL1 and CDPK1.\",\n      \"evidence\": \"Chemical mutagenesis/BKI-1748 selection, whole-genome sequencing, Leu162Gln knock-in, and enzymatic/structural modeling with gatekeeper substitutions in T. gondii\",\n      \"pmids\": [\"40407244\", \"40339062\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"No high-resolution structure of the inhibited kinase\", \"Native regulatory phosphorylation events unmapped\"],\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2026,\n      \"claim\": \"Dual inhibition of MAPKL1 and CDPK1 by BKI-1748 was shown to be therapeutically effective against congenital toxoplasmosis in a large-animal model.\",\n      \"evidence\": \"Pregnant sheep infection model with oral BKI-1748, serology, and parasite detection in offspring in T. gondii TgShSp1\",\n      \"pmids\": [\"42125495\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Efficacy is attributed to dual kinase inhibition but not deconvoluted to MAPKL1 alone\", \"Mechanistic contribution of MAPKL1 not re-tested in this model\"],\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"TgShSp1\"}]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How TgMAPKL1 is activated in the absence of a canonical MAPK cascade, and which centrosomal substrates it phosphorylates to control duplication and cytokinesis, remain unknown.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Low\",\n      \"gaps\": [\"No upstream activating kinase or non-canonical regulatory mechanism identified\", \"No direct phosphorylation substrate mapped\", \"No experimental structure available\"],\n      \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0004674\", \"supporting_discovery_ids\": [0, 4, 6, 7], \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]},\n      {\"term_id\": \"GO:0005524\", \"supporting_discovery_ids\": [4, 6], \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005813\", \"supporting_discovery_ids\": [3, 5], \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"GO:0010824\", \"supporting_discovery_ids\": [3, 5], \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]},\n      {\"term_id\": \"GO:0000281\", \"supporting_discovery_ids\": [4], \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"RH\"}]},\n      {\"term_id\": \"GO:0051301\", \"supporting_discovery_ids\": [3, 4], \"attribution\": [{\"species\": \"Toxoplasma gondii\", \"strain\": \"\"}]}\n    ],\n    \"complexes\": [],\n    \"partners\": [],\n    \"other_free_text\": [\n      \"Protozoan-specific MAPK-related subfamily distinct from ERK/JNK/p38 [#0].\",\n      \"Gatekeeper residue Ser191 and ATP-site residue Leu162 govern bumped kinase inhibitor sensitivity/resistance [#4, #6].\",\n      \"Direct molecular target of bumped kinase inhibitors (1NM-PP1, BKI-1748, (R)-RY-1-165/-185), co-targeted with TgCDPK1 [#4, #6, #7].\",\n      \"Acts on a step of centrosome duplication distinct from that regulated by TgMAPK2 [#5].\",\n      \"Regulated by a non-canonical mechanism, as apicomplexans lack the canonical MAPK kinase cascade [#8].\"\n    ]\n  },\n  \"strain_conflicts\": []\n}","audit_flag":null,"strains":[{"strain":"ME49","gene_id":"TGME49_312570","name":"MAPKL1","product":"CMGC kinase, MAPK family (ERK) MAPK-1","uniprot_acc":"S8EUF0","chromosome":"TGME49_chrXI","start_pos":2785457},{"strain":"GT1","gene_id":"TGGT1_312570","name":null,"product":"CMGC kinase, MAPK family (ERK) MAPK-1","uniprot_acc":null,"chromosome":"TGGT1_chrXI","start_pos":2750081},{"strain":"RH88","gene_id":"TGRH88_051820","name":null,"product":"CMGC kinase, MAPK family (ERK) MAPK-1","uniprot_acc":null,"chromosome":"CM023092","start_pos":2835773},{"strain":"VEG","gene_id":"TGVEG_312570","name":null,"product":"CMGC kinase, MAPK family (ERK) MAPK-1","uniprot_acc":"A0A125YKL1","chromosome":"TGVEG_chrXI","start_pos":2799326}]}