{"gene":"PF3D7_1230400","run_date":"2026-09-08T14:19:06","timeline":{"discoveries":[{"year":2007,"finding":"Recombinant P. falciparum ClpQ (PfHslV/PF3D7_1230400) exhibits threonine protease-specific activity as well as chymotrypsin-like and peptidyl glutamyl peptide hydrolase activities in vitro; all three activities are inhibited by their respective specific inhibitors.","method":"In vitro protease activity assays with recombinant protein; inhibitor studies","journal":"Molecular and biochemical parasitology","confidence":"High","confidence_rationale":"Tier 1 / Moderate — direct in vitro enzymatic characterization of recombinant protein with multiple activity classes and specific inhibitors, single lab but multiple orthogonal assays","pmids":["17270290"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2007,"finding":"ClpQ (PF3D7_1230400) localizes to the cytosol of P. falciparum asexual-stage parasites as a soluble protein, as determined by Western immunoblotting of parasite fractions and immunofluorescence microscopy.","method":"Subcellular fractionation with Western blot; immunofluorescence microscopy","journal":"Molecular and biochemical parasitology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — two orthogonal localization methods (fractionation + IFA), single lab","pmids":["17270290"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2007,"finding":"ClpQ (PF3D7_1230400) degrades GFP fused to Arc-repressor (a known HslV substrate in prokaryotes) in a transgenic parasite line, confirming protease activity in vivo.","method":"Transgenic parasite line expressing GFP-Arc-repressor fusion; GFP degradation assay","journal":"Molecular and biochemical parasitology","confidence":"Medium","confidence_rationale":"Tier 2 / Weak — clean in-parasite substrate degradation assay, single lab, single experiment","pmids":["17270290"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2006,"finding":"ClpQ (PF3D7_1230400) is detectable only in schizonts and merozoites, indicating stage-specific expression restricted to late asexual blood stages.","method":"Western blot analysis across intraerythrocytic stages","journal":"Molecular and biochemical parasitology","confidence":"Medium","confidence_rationale":"Tier 2 / Weak — direct protein detection across cell cycle, single lab, single method","pmids":["16616382"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2011,"finding":"ClpQ (PF3D7_1230400) physically interacts with the ClpY ATPase component to form the ClpQY protease complex; a short stretch of residues at the C-terminus of PfClpY is required for this interaction, as shown by characterization of the interaction and disruption with a synthetic peptide corresponding to that region.","method":"Interaction characterization (binding assays); synthetic C-terminal peptide competition/disruption","journal":"Cell death & disease","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — direct interaction characterization with functional disruption by competing peptide, single lab, two complementary approaches","pmids":["22113196"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2011,"finding":"Disruption of the ClpQY complex (by a synthetic peptide antagonizing ClpQ–ClpY interaction) impairs asexual parasite growth and maturation, causes mitochondrial dysfunction and loss of mitochondrial membrane potential, activates VAD-FMK-binding proteases and nucleases, and culminates in apoptosis-like cell death, placing ClpQ functionally in mitochondrial homeostasis and parasite survival.","method":"Synthetic inhibitory peptide treatment of P. falciparum cultures; growth assays; mitochondrial membrane potential measurements; VAD-FMK protease/nuclease activation assays","journal":"Cell death & disease","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — multiple orthogonal cellular phenotypic readouts in parasite, single lab","pmids":["22113196"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2018,"finding":"ClpQ (PF3D7_1230400) is reported to localize to the mitochondria of P. falciparum (in contrast to the earlier cytosolic localization report), based on in silico prediction combined with immunoprecipitation/localization analysis in the context of a review integrating experimental data.","method":"In silico prediction combined with immunoprecipitation analysis (cited in review)","journal":"Translational research","confidence":"Low","confidence_rationale":"Tier 4 / Weak — secondary review citing prior analyses; no new primary localization experiment described; contradicts PMID 17270290's cytosolic finding","pmids":["30009761"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2024,"finding":"Inhibition of ClpQ (PF3D7_1230400) protease activity under mitochondrial-specific stress conditions, combined with depletion of PfPhb2, results in enhanced parasite growth inhibition, mitochondrial ROS production, mitochondrial membrane potential loss, and mitochondrial fission/fragmentation leading to apoptosis-like cell death, indicating that ClpQ functions in mitochondrial protein stabilization and homeostasis.","method":"Inducible knockdown (GlmS ribozyme) of PfPhb2 combined with pharmacological inhibition of ClpQ; parasite growth assays; mitochondrial ROS and membrane potential measurements; microscopic assessment of mitochondrial morphology","journal":"Mitochondrion","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — multiple orthogonal functional readouts in parasite, single lab, ClpQ role inferred via pharmacological inhibition in combination with genetic KD","pmids":["39245193"],"is_preprint":false,"attribution":[{"species":"Plasmodium falciparum","strain":""}]}],"current_model":"P. falciparum ClpQ (PF3D7_1230400) is an ATP-dependent threonine protease that forms a ClpQY complex with the ClpY ATPase via the C-terminal residues of ClpY; it possesses chymotrypsin-like, threonine-protease, and peptidyl-glutamyl-peptide-hydrolase activities in vitro, can degrade prokaryotic substrates in vivo, localizes to the parasite mitochondrion (with conflicting early cytosolic localization data), and is required for mitochondrial homeostasis and parasite survival during asexual blood-stage development, as its disruption triggers mitochondrial dysfunction and apoptosis-like cell death."},"narrative":{"mechanistic_narrative":"PF3D7_1230400 (ClpQ) is an ATP-dependent threonine protease of P. falciparum that provides proteolytic capacity essential for mitochondrial homeostasis and asexual blood-stage survival [PMID:17270290, PMID:22113196]. Recombinant ClpQ displays threonine-protease, chymotrypsin-like, and peptidyl-glutamyl-peptide-hydrolase activities in vitro, each blocked by its cognate inhibitor, and the enzyme degrades a prokaryotic HslV substrate (GFP-Arc-repressor) when expressed in transgenic parasites, confirming proteolytic activity in vivo [PMID:17270290]. ClpQ functions not as an isolated protease but as the peptidase subunit of the ClpQY complex, associating with the ClpY ATPase through a short C-terminal stretch of ClpY; a synthetic peptide mimicking this region disrupts the interaction [PMID:22113196]. Antagonizing the ClpQ–ClpY interaction impairs parasite growth and maturation and triggers mitochondrial dysfunction — loss of membrane potential, activation of VAD-FMK-binding proteases and nucleases, and apoptosis-like death — establishing ClpQ's role in mitochondrial protein turnover and parasite viability [PMID:22113196, PMID:39245193]. Localization evidence is discordant across the corpus: early fractionation and immunofluorescence placed ClpQ in the parasite cytosol [PMID:17270290], whereas a later analysis assigned it to the mitochondrion [PMID:30009761]. The protein is expressed in a stage-restricted manner, detectable only in schizonts and merozoites [PMID:16616382]. Beyond these findings, no structural model of the parasite complex or defined endogenous substrate has been characterized in the available corpus.","teleology":[{"year":2006,"claim":"Establishing when ClpQ protein is present across the intraerythrocytic cycle framed its likely window of action, showing it is a late-stage factor rather than a constitutively present housekeeping protease.","evidence":"Western blot across intraerythrocytic stages in P. falciparum","pmids":["16616382"],"confidence":"Medium","gaps":["Does not address function or localization","Single method/single lab; no transcript-to-protein correlation"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2007,"claim":"Determining that recombinant ClpQ is enzymatically active answered whether the annotated protease is a functional peptidase, defining it as a threonine protease with multiple catalytic activities confirmed by inhibitor specificity and by degradation of a heterologous substrate in parasites.","evidence":"In vitro protease assays with recombinant protein plus inhibitor studies, and in-parasite GFP-Arc-repressor degradation; parallel fractionation/IFA localization","pmids":["17270290"],"confidence":"High","gaps":["No endogenous parasite substrate identified","Cytosolic localization by this study conflicts with later mitochondrial assignment","Activities characterized on model/heterologous substrates only"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2011,"claim":"Identifying ClpY as ClpQ's partner and mapping the interaction to a short ClpY C-terminal region answered how ClpQ is assembled into a functional protease and provided a means to disrupt it, linking complex integrity to mitochondrial homeostasis and parasite survival.","evidence":"Interaction/binding characterization with synthetic C-terminal peptide competition; growth, mitochondrial membrane potential, and VAD-FMK protease/nuclease assays in P. falciparum","pmids":["22113196"],"confidence":"Medium","gaps":["Phenotypes derive from peptide antagonism rather than genetic ablation of ClpQ itself","Stoichiometry and structure of the ClpQY complex not resolved","Mechanistic link between complex disruption and apoptosis-like death undefined"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2018,"claim":"Reassessing ClpQ localization addressed the discrepancy over its subcellular site, assigning it to the mitochondrion in contrast to the earlier cytosolic report.","evidence":"In silico prediction plus immunoprecipitation/localization analysis cited in a review","pmids":["30009761"],"confidence":"Low","gaps":["Secondary review with no new primary localization experiment described","Directly contradicts the cytosolic finding of PMID 17270290","Import/targeting signal not experimentally defined"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":2024,"claim":"Combining ClpQ pharmacological inhibition with PfPhb2 depletion under mitochondrial stress answered whether ClpQ contributes to mitochondrial protein quality control, showing that loss of its activity exacerbates mitochondrial ROS, membrane depolarization, and fission leading to apoptosis-like death.","evidence":"GlmS-inducible PfPhb2 knockdown combined with pharmacological ClpQ inhibition; growth, mitochondrial ROS, membrane potential, and morphology assays in P. falciparum","pmids":["39245193"],"confidence":"Medium","gaps":["ClpQ role inferred via pharmacological inhibition, not direct genetic ablation","Inhibitor specificity for ClpQ not established","Direct substrates whose stabilization maintains mitochondrial integrity unknown"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]},{"year":null,"claim":"The endogenous substrate repertoire of ClpQ, the structure of the parasite ClpQY complex, and its definitive subcellular localization remain unresolved.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No native parasite substrate identified","Localization conflict (cytosol vs mitochondrion) unresolved","No genetic knockout of ClpQ reported; phenotypes rest on peptide or pharmacological disruption"],"attribution":[{"species":"Plasmodium falciparum","strain":""}]}],"mechanism_profile":{"molecular_activity":[],"localization":[],"pathway":[],"complexes":["ClpQY protease complex (ClpQ peptidase + ClpY ATPase) [#4]"],"partners":["CLPY ATPASE [#4]","PFPHB2 (FUNCTIONAL INTERACTION UNDER MITOCHONDRIAL STRESS) [#7]"],"other_free_text":["Stage-restricted expression: detectable only in schizonts and merozoites [#3]","Interaction with ClpY mapped to a short C-terminal region of ClpY; disruptable by a synthetic mimic peptide [#4]","Localization is discordant across the corpus: cytosolic by fractionation/IFA [#1] versus mitochondrial by later analysis [#6]","Functional characterization relies on peptide-based complex disruption [#5] and pharmacological inhibition combined with PfPhb2 knockdown [#7]; no direct genetic knockout of PF3D7_1230400 is reported in the corpus"]}},"prefetch_data":{},"corpus_meta":[{"pmid":"24533266","id":"PMC_24533266","title":"The proteasome of malaria parasites: A multi-stage drug target for chemotherapeutic intervention?","date":"2012","source":"International journal for parasitology. Drugs and drug resistance","url":"https://pubmed.ncbi.nlm.nih.gov/24533266","citation_count":64,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["ClpQ"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"33497624","id":"PMC_33497624","title":"Structure, function, and substrates of Clp AAA+ protease systems in cyanobacteria, plastids, and apicoplasts: A comparative analysis.","date":"2021","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/33497624","citation_count":61,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["ATP"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"30009761","id":"PMC_30009761","title":"The proteasome as a target to combat malaria: hits and misses.","date":"2018","source":"Translational research : the journal of laboratory and clinical medicine","url":"https://pubmed.ncbi.nlm.nih.gov/30009761","citation_count":37,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["ClpQ"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"17270290","id":"PMC_17270290","title":"Characterization and localization of Plasmodium falciparum homolog of prokaryotic ClpQ/HslV protease.","date":"2007","source":"Molecular and biochemical parasitology","url":"https://pubmed.ncbi.nlm.nih.gov/17270290","citation_count":35,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["ClpQ","ATP"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"22113196","id":"PMC_22113196","title":"Disruption of a mitochondrial protease machinery in Plasmodium falciparum is an intrinsic signal for parasite cell death.","date":"2011","source":"Cell death & disease","url":"https://pubmed.ncbi.nlm.nih.gov/22113196","citation_count":34,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["ClpQ","ATP","PfClpQ"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"16616382","id":"PMC_16616382","title":"Plasmodia express two threonine-peptidase complexes during asexual development.","date":"2006","source":"Molecular and biochemical parasitology","url":"https://pubmed.ncbi.nlm.nih.gov/16616382","citation_count":31,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["ClpQ"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"34882737","id":"PMC_34882737","title":"Microbial proteasomes as drug targets.","date":"2021","source":"PLoS pathogens","url":"https://pubmed.ncbi.nlm.nih.gov/34882737","citation_count":23,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["ATP"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"28875841","id":"PMC_28875841","title":"New Molecular Targets and Strategies for Antimalarial Discovery.","date":"2019","source":"Current medicinal chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/28875841","citation_count":23,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["ATP"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"28917450","id":"PMC_28917450","title":"A novel class of Plasmodial ClpP protease inhibitors as potential antimalarial agents.","date":"2017","source":"Bioorganic & medicinal chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/28917450","citation_count":22,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["ATP"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false},{"pmid":"39245193","id":"PMC_39245193","title":"Unravelling the anti-apoptotic role of Plasmodium falciparum Prohibitin-2 (PfPhb2) in maintaining mitochondrial homeostasis.","date":"2024","source":"Mitochondrion","url":"https://pubmed.ncbi.nlm.nih.gov/39245193","citation_count":3,"is_preprint":false,"source_species":["Pf"],"role":"primary","match_terms":["ClpQ"],"competing_organism_flag":false,"competing_organism_match":"","competing_organism_only":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":7185,"output_tokens":2085,"usd":0.026415,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":7386,"output_tokens":2999,"usd":0.055953,"stage2_stop_reason":"end_turn"},"total_usd":0.082368,"stage1_batch_id":"msgbatch_011BPjN2BL33F8cJXD1r7V7T","stage2_batch_id":"msgbatch_01Qwg6vP7qxkpL6Gsc7tajsb","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2007,\n      \"finding\": \"Recombinant P. falciparum ClpQ (PfHslV/PF3D7_1230400) exhibits threonine protease-specific activity as well as chymotrypsin-like and peptidyl glutamyl peptide hydrolase activities in vitro; all three activities are inhibited by their respective specific inhibitors.\",\n      \"method\": \"In vitro protease activity assays with recombinant protein; inhibitor studies\",\n      \"journal\": \"Molecular and biochemical parasitology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — direct in vitro enzymatic characterization of recombinant protein with multiple activity classes and specific inhibitors, single lab but multiple orthogonal assays\",\n      \"pmids\": [\"17270290\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2007,\n      \"finding\": \"ClpQ (PF3D7_1230400) localizes to the cytosol of P. falciparum asexual-stage parasites as a soluble protein, as determined by Western immunoblotting of parasite fractions and immunofluorescence microscopy.\",\n      \"method\": \"Subcellular fractionation with Western blot; immunofluorescence microscopy\",\n      \"journal\": \"Molecular and biochemical parasitology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — two orthogonal localization methods (fractionation + IFA), single lab\",\n      \"pmids\": [\"17270290\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2007,\n      \"finding\": \"ClpQ (PF3D7_1230400) degrades GFP fused to Arc-repressor (a known HslV substrate in prokaryotes) in a transgenic parasite line, confirming protease activity in vivo.\",\n      \"method\": \"Transgenic parasite line expressing GFP-Arc-repressor fusion; GFP degradation assay\",\n      \"journal\": \"Molecular and biochemical parasitology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Weak — clean in-parasite substrate degradation assay, single lab, single experiment\",\n      \"pmids\": [\"17270290\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2006,\n      \"finding\": \"ClpQ (PF3D7_1230400) is detectable only in schizonts and merozoites, indicating stage-specific expression restricted to late asexual blood stages.\",\n      \"method\": \"Western blot analysis across intraerythrocytic stages\",\n      \"journal\": \"Molecular and biochemical parasitology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Weak — direct protein detection across cell cycle, single lab, single method\",\n      \"pmids\": [\"16616382\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"ClpQ (PF3D7_1230400) physically interacts with the ClpY ATPase component to form the ClpQY protease complex; a short stretch of residues at the C-terminus of PfClpY is required for this interaction, as shown by characterization of the interaction and disruption with a synthetic peptide corresponding to that region.\",\n      \"method\": \"Interaction characterization (binding assays); synthetic C-terminal peptide competition/disruption\",\n      \"journal\": \"Cell death & disease\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — direct interaction characterization with functional disruption by competing peptide, single lab, two complementary approaches\",\n      \"pmids\": [\"22113196\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"Disruption of the ClpQY complex (by a synthetic peptide antagonizing ClpQ–ClpY interaction) impairs asexual parasite growth and maturation, causes mitochondrial dysfunction and loss of mitochondrial membrane potential, activates VAD-FMK-binding proteases and nucleases, and culminates in apoptosis-like cell death, placing ClpQ functionally in mitochondrial homeostasis and parasite survival.\",\n      \"method\": \"Synthetic inhibitory peptide treatment of P. falciparum cultures; growth assays; mitochondrial membrane potential measurements; VAD-FMK protease/nuclease activation assays\",\n      \"journal\": \"Cell death & disease\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — multiple orthogonal cellular phenotypic readouts in parasite, single lab\",\n      \"pmids\": [\"22113196\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"ClpQ (PF3D7_1230400) is reported to localize to the mitochondria of P. falciparum (in contrast to the earlier cytosolic localization report), based on in silico prediction combined with immunoprecipitation/localization analysis in the context of a review integrating experimental data.\",\n      \"method\": \"In silico prediction combined with immunoprecipitation analysis (cited in review)\",\n      \"journal\": \"Translational research\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 4 / Weak — secondary review citing prior analyses; no new primary localization experiment described; contradicts PMID 17270290's cytosolic finding\",\n      \"pmids\": [\"30009761\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"Inhibition of ClpQ (PF3D7_1230400) protease activity under mitochondrial-specific stress conditions, combined with depletion of PfPhb2, results in enhanced parasite growth inhibition, mitochondrial ROS production, mitochondrial membrane potential loss, and mitochondrial fission/fragmentation leading to apoptosis-like cell death, indicating that ClpQ functions in mitochondrial protein stabilization and homeostasis.\",\n      \"method\": \"Inducible knockdown (GlmS ribozyme) of PfPhb2 combined with pharmacological inhibition of ClpQ; parasite growth assays; mitochondrial ROS and membrane potential measurements; microscopic assessment of mitochondrial morphology\",\n      \"journal\": \"Mitochondrion\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — multiple orthogonal functional readouts in parasite, single lab, ClpQ role inferred via pharmacological inhibition in combination with genetic KD\",\n      \"pmids\": [\"39245193\"],\n      \"is_preprint\": false,\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    }\n  ],\n  \"current_model\": \"P. falciparum ClpQ (PF3D7_1230400) is an ATP-dependent threonine protease that forms a ClpQY complex with the ClpY ATPase via the C-terminal residues of ClpY; it possesses chymotrypsin-like, threonine-protease, and peptidyl-glutamyl-peptide-hydrolase activities in vitro, can degrade prokaryotic substrates in vivo, localizes to the parasite mitochondrion (with conflicting early cytosolic localization data), and is required for mitochondrial homeostasis and parasite survival during asexual blood-stage development, as its disruption triggers mitochondrial dysfunction and apoptosis-like cell death.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"PF3D7_1230400 (ClpQ) is an ATP-dependent threonine protease of P. falciparum that provides proteolytic capacity essential for mitochondrial homeostasis and asexual blood-stage survival [#0, #5]. Recombinant ClpQ displays threonine-protease, chymotrypsin-like, and peptidyl-glutamyl-peptide-hydrolase activities in vitro, each blocked by its cognate inhibitor, and the enzyme degrades a prokaryotic HslV substrate (GFP-Arc-repressor) when expressed in transgenic parasites, confirming proteolytic activity in vivo [#0, #2]. ClpQ functions not as an isolated protease but as the peptidase subunit of the ClpQY complex, associating with the ClpY ATPase through a short C-terminal stretch of ClpY; a synthetic peptide mimicking this region disrupts the interaction [#4]. Antagonizing the ClpQ–ClpY interaction impairs parasite growth and maturation and triggers mitochondrial dysfunction — loss of membrane potential, activation of VAD-FMK-binding proteases and nucleases, and apoptosis-like death — establishing ClpQ's role in mitochondrial protein turnover and parasite viability [#5, #7]. Localization evidence is discordant across the corpus: early fractionation and immunofluorescence placed ClpQ in the parasite cytosol [#1], whereas a later analysis assigned it to the mitochondrion [#6]. The protein is expressed in a stage-restricted manner, detectable only in schizonts and merozoites [#3]. Beyond these findings, no structural model of the parasite complex or defined endogenous substrate has been characterized in the available corpus.\",\n  \"teleology\": [\n    {\n      \"year\": 2006,\n      \"claim\": \"Establishing when ClpQ protein is present across the intraerythrocytic cycle framed its likely window of action, showing it is a late-stage factor rather than a constitutively present housekeeping protease.\",\n      \"evidence\": \"Western blot across intraerythrocytic stages in P. falciparum\",\n      \"pmids\": [\"16616382\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Does not address function or localization\", \"Single method/single lab; no transcript-to-protein correlation\"],\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2007,\n      \"claim\": \"Determining that recombinant ClpQ is enzymatically active answered whether the annotated protease is a functional peptidase, defining it as a threonine protease with multiple catalytic activities confirmed by inhibitor specificity and by degradation of a heterologous substrate in parasites.\",\n      \"evidence\": \"In vitro protease assays with recombinant protein plus inhibitor studies, and in-parasite GFP-Arc-repressor degradation; parallel fractionation/IFA localization\",\n      \"pmids\": [\"17270290\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"No endogenous parasite substrate identified\", \"Cytosolic localization by this study conflicts with later mitochondrial assignment\", \"Activities characterized on model/heterologous substrates only\"],\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2011,\n      \"claim\": \"Identifying ClpY as ClpQ's partner and mapping the interaction to a short ClpY C-terminal region answered how ClpQ is assembled into a functional protease and provided a means to disrupt it, linking complex integrity to mitochondrial homeostasis and parasite survival.\",\n      \"evidence\": \"Interaction/binding characterization with synthetic C-terminal peptide competition; growth, mitochondrial membrane potential, and VAD-FMK protease/nuclease assays in P. falciparum\",\n      \"pmids\": [\"22113196\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Phenotypes derive from peptide antagonism rather than genetic ablation of ClpQ itself\", \"Stoichiometry and structure of the ClpQY complex not resolved\", \"Mechanistic link between complex disruption and apoptosis-like death undefined\"],\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2018,\n      \"claim\": \"Reassessing ClpQ localization addressed the discrepancy over its subcellular site, assigning it to the mitochondrion in contrast to the earlier cytosolic report.\",\n      \"evidence\": \"In silico prediction plus immunoprecipitation/localization analysis cited in a review\",\n      \"pmids\": [\"30009761\"],\n      \"confidence\": \"Low\",\n      \"gaps\": [\"Secondary review with no new primary localization experiment described\", \"Directly contradicts the cytosolic finding of PMID 17270290\", \"Import/targeting signal not experimentally defined\"],\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Combining ClpQ pharmacological inhibition with PfPhb2 depletion under mitochondrial stress answered whether ClpQ contributes to mitochondrial protein quality control, showing that loss of its activity exacerbates mitochondrial ROS, membrane depolarization, and fission leading to apoptosis-like death.\",\n      \"evidence\": \"GlmS-inducible PfPhb2 knockdown combined with pharmacological ClpQ inhibition; growth, mitochondrial ROS, membrane potential, and morphology assays in P. falciparum\",\n      \"pmids\": [\"39245193\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"ClpQ role inferred via pharmacological inhibition, not direct genetic ablation\", \"Inhibitor specificity for ClpQ not established\", \"Direct substrates whose stabilization maintains mitochondrial integrity unknown\"],\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"The endogenous substrate repertoire of ClpQ, the structure of the parasite ClpQY complex, and its definitive subcellular localization remain unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No native parasite substrate identified\", \"Localization conflict (cytosol vs mitochondrion) unresolved\", \"No genetic knockout of ClpQ reported; phenotypes rest on peptide or pharmacological disruption\"],\n      \"attribution\": [{\"species\": \"Plasmodium falciparum\", \"strain\": \"\"}]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0004298\", \"supporting_discovery_ids\": [0, 2]},\n      {\"term_id\": \"GO:0004252\", \"supporting_discovery_ids\": [0]},\n      {\"term_id\": \"GO:0006508\", \"supporting_discovery_ids\": [0, 2]},\n      {\"term_id\": \"GO:0042803\", \"supporting_discovery_ids\": [4]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005829\", \"supporting_discovery_ids\": [1]},\n      {\"term_id\": \"GO:0005739\", \"supporting_discovery_ids\": [6, 7]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"GO:0007005\", \"supporting_discovery_ids\": [5, 7]},\n      {\"term_id\": \"GO:0006515\", \"supporting_discovery_ids\": [7]},\n      {\"term_id\": \"GO:0012501\", \"supporting_discovery_ids\": [5, 7]}\n    ],\n    \"complexes\": [\"ClpQY protease complex (ClpQ peptidase + ClpY ATPase) [#4]\"],\n    \"partners\": [\"ClpY ATPase [#4]\", \"PfPhb2 (functional interaction under mitochondrial stress) [#7]\"],\n    \"other_free_text\": [\n      \"Stage-restricted expression: detectable only in schizonts and merozoites [#3]\",\n      \"Interaction with ClpY mapped to a short C-terminal region of ClpY; disruptable by a synthetic mimic peptide [#4]\",\n      \"Localization is discordant across the corpus: cytosolic by fractionation/IFA [#1] versus mitochondrial by later analysis [#6]\",\n      \"Functional characterization relies on peptide-based complex disruption [#5] and pharmacological inhibition combined with PfPhb2 knockdown [#7]; no direct genetic knockout of PF3D7_1230400 is reported in the corpus\"\n    ]\n  }\n}","audit_flag":null,"strains":[{"strain":"Pf3D7","gene_id":"PF3D7_1230400","name":null,"product":"ATP-dependent protease subunit ClpQ","uniprot_acc":null,"chromosome":null,"start_pos":null},{"strain":"PbANKA","gene_id":"PBANKA_1445100","name":null,"product":"ATP-dependent protease subunit ClpQ, putative","uniprot_acc":null,"chromosome":null,"start_pos":null},{"strain":"PkH","gene_id":"PKNH_1449800","name":null,"product":"ATP-dependent protease subunit ClpQ, putative","uniprot_acc":null,"chromosome":null,"start_pos":null}],"gene_symbol":"ClpQ","evaluation":null}