{"gene":"TSPO","run_date":"2026-06-10T10:51:56","timeline":{"discoveries":[{"year":2015,"finding":"Crystal structures of TSPO from Rhodobacter sphaeroides at 1.8, 2.4, and 2.5 Å resolution (lipidic cubic phase) revealed a tightly interacting dimer, the binding site of an endogenous porphyrin ligand, and conformational effects of the human Ala147→Thr147 polymorphism on cholesterol binding.","method":"X-ray crystallography (lipidic cubic phase), site-directed mutagenesis to mimic human polymorphism","journal":"Science","confidence":"High","confidence_rationale":"Tier 1 / Strong — atomic-resolution crystal structures with multiple resolutions, mutagenesis validation, and independent structural confirmation","pmids":["25635101"],"is_preprint":false},{"year":2014,"finding":"NMR structure of mouse TSPO in complex with PK11195 showed a rigid five-helix bundle when bound to the ligand; in the absence of PK11195, TSPO exchanges between multiple conformations with extensive motions on pico- to microsecond timescales and local unfolding near the ligand-binding site.","method":"NMR spectroscopy (solution-state), ligand binding/unbinding studies","journal":"Science / Chemistry (Weinheim)","confidence":"High","confidence_rationale":"Tier 1 / Strong — atomic-resolution NMR structure with ligand, conformational dynamics characterised by multiple NMR parameters, replicated across two related papers","pmids":["26394723","26551694"],"is_preprint":false},{"year":2016,"finding":"CRISPR/Cas9 knockout of TSPO in steroidogenic MA-10 Leydig cells caused a shift in mitochondrial substrate utilisation from glucose to fatty acids, with significantly higher fatty acid oxidation (FAO) and increased reactive oxygen species production, but no change in oxygen consumption rate, membrane potential, or proton leak; consistent upregulation of FAO genes was found in adrenal glands of global Tspo−/− mice.","method":"CRISPR/Cas9 knockout, Seahorse metabolic flux analysis, gene expression profiling, global TSPO knockout mouse model","journal":"Endocrinology","confidence":"High","confidence_rationale":"Tier 2 / Strong — CRISPR KO in vitro corroborated by in vivo knockout mouse, multiple orthogonal metabolic readouts","pmids":["26741196"],"is_preprint":false},{"year":2014,"finding":"Global C57BL/6 Tspo knockout mice are viable with normal growth, lifespan, cholesterol transport, blood pregnenolone concentration, protoporphyrin IX metabolism, fertility, and behaviour, directly challenging the model that TSPO is essential for cholesterol transport and steroidogenesis. However, microglia from TSPO knockouts produced significantly less ATP, indicating reduced metabolic activity.","method":"Global gene knockout mouse model, PET imaging with PK11195/CLINDE/PBR111, biochemical assays (cholesterol, pregnenolone, protoporphyrin IX), ATP measurement in isolated microglia","journal":"Nature Communications","confidence":"High","confidence_rationale":"Tier 2 / Strong — complete knockout animal model with multiple orthogonal biochemical and functional readouts, published in peer-reviewed journal","pmids":["25406832"],"is_preprint":false},{"year":2003,"finding":"TSPO (PBR) interacts with PAP7, a protein that also binds the PKA regulatory subunit RIα; PAP7 is localized to Golgi and mitochondria. Inhibition of PAP7 expression reduced hormone-induced cholesterol transport into mitochondria and decreased steroid formation, placing PAP7 as an AKAP linking cAMP/PKA signalling to TSPO-mediated cholesterol transport.","method":"Protein interaction identification (phage display, co-immunoprecipitation), antisense oligonucleotide knockdown, steroid production assay","journal":"Journal of Steroid Biochemistry and Molecular Biology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — reciprocal protein interaction plus functional knockdown readout, single lab","pmids":["12943713"],"is_preprint":false},{"year":2002,"finding":"Antisense knockdown of TSPO (PBR) in MA-10 Leydig cells reduced PBR protein levels and inhibited hormone-stimulated steroid formation; a 7-mer competitive PBR peptide antagonist identified by phage display also inhibited benzodiazepine- and hormone-stimulated steroid production when transduced into Leydig cells, supporting the requirement for endogenous PBR agonist–receptor interaction in steroidogenesis.","method":"Antisense oligonucleotide knockdown, phage display peptide antagonist, steroid production assay","journal":"Endocrine Research","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — loss-of-function (antisense) plus orthogonal peptide antagonist approach, single lab","pmids":["12530641"],"is_preprint":false},{"year":1992,"finding":"Immunocytochemistry and confocal microscopy with 3D reconstruction in mouse adrenal cortex demonstrated that a subset of PBR/TSPO localises to the plasma membrane in zona fasciculata cells, in addition to the mitochondrial pool, suggesting functions not restricted to mitochondria.","method":"Anti-peptide immunocytochemistry, biotin-streptavidin peroxidase staining, confocal microscopy with 3D reconstruction","journal":"Molecular and Cellular Endocrinology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — direct subcellular localisation by confocal microscopy with 3D reconstruction, single lab, single method","pmids":["1332905"],"is_preprint":false},{"year":2020,"finding":"TSPO deficiency (knockout mice and siRNA knockdown cell line) significantly inhibited microglial activation induced by LPS or IL-4, decreased mitochondrial membrane potential and ATP production, and suppressed both mitochondrial OXPHOS and glycolysis, demonstrating that TSPO regulates microglial activation through control of mitochondrial metabolism.","method":"TSPO knockout mouse-derived primary microglia, siRNA knockdown cell line, LPS/IL-4 activation assays, Seahorse metabolic analysis, mitochondrial membrane potential measurement, ATP assay","journal":"Frontiers in Pharmacology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — two genetic loss-of-function systems (KO mice + siRNA) with multiple metabolic readouts, single lab","pmids":["32695005"],"is_preprint":false},{"year":2020,"finding":"Conditional deletion of TSPO in retinal microglia (Cx3cr1-CreERT2:TSPOfl/fl) or treatment with the TSPO ligand XBD173 prevented microglial/phagocyte reactivity and subsequent neoangiogenesis in the laser-induced neovascular AMD model. Using NADPH oxidase-deficient mice, TSPO was identified as a key regulator of NOX1-dependent neurotoxic ROS production in the retina.","method":"Conditional knockout mouse (Cx3cr1-CreERT2:TSPOfl/fl), pharmacological ligand treatment (XBD173), NADPH oxidase-deficient mouse strains (genetic epistasis), laser-induced choroidal neovascularisation model","journal":"Nature Communications","confidence":"High","confidence_rationale":"Tier 2 / Strong — conditional cell-type-specific KO combined with genetic epistasis using multiple NOX-deficient mouse lines, published in high-tier journal","pmids":["32483169"],"is_preprint":false},{"year":2019,"finding":"Tanycyte-specific deletion of TSPO (Rax-Cre) in the hypothalamus and intracerebroventricular administration of PK11195 reduced food intake and elevated energy expenditure in high-fat diet conditions; ablation of tanycytic TSPO elicited AMPK-dependent lipophagy, breaking down lipid droplets to free fatty acids and elevating ATP, linking TSPO to hypothalamic lipid sensing and energy balance via autophagy regulation.","method":"Tanycyte-specific conditional knockout (Rax-Cre), intracerebroventricular ligand injection, metabolic cage studies, lipophagy/autophagy assays, AMPK pathway analysis","journal":"Autophagy","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — cell-type-specific KO with mechanistic pathway dissection (AMPK-lipophagy), single lab","pmids":["31469345"],"is_preprint":false},{"year":2022,"finding":"Diazepam impaired structural plasticity of dendritic spines and caused cognitive impairment in mice via TSPO (not GABAA receptors), altering microglial morphology and enhancing microglial phagocytosis of synaptic material (spine engulfment); this was demonstrated using TSPO-specific genetic approaches.","method":"In vivo mouse model, TSPO-specific genetic manipulation (knockouts/ligands), two-photon microscopy of spine dynamics, microglial phagocytosis assays, PET imaging","journal":"Nature Neuroscience","confidence":"High","confidence_rationale":"Tier 2 / Strong — genetic dissection of TSPO vs. GABAA receptor contributions with multiple in vivo functional readouts, published in high-tier journal","pmids":["35228700"],"is_preprint":false},{"year":2023,"finding":"TSPO directly interacts with p62/SQSTM1 in hepatocellular carcinoma cells, interfering with autophagy and causing p62 accumulation; accumulated p62 competes with KEAP1, preventing KEAP1-mediated proteasomal degradation of Nrf2, thereby activating Nrf2-dependent antioxidant defence to inhibit ferroptosis and upregulating PD-L1 expression to promote immune evasion.","method":"Co-immunoprecipitation (TSPO–p62 interaction), gain- and loss-of-function experiments, autophagy assays, Nrf2/KEAP1/p62 pathway analysis, PD-L1 expression measurement, in vitro and in vivo tumour models","journal":"Advanced Science","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — Co-IP plus functional pathway dissection with gain/loss of function, single lab","pmids":["36994647"],"is_preprint":false},{"year":2017,"finding":"Stable transfection of TSPO into TSPO-low Jurkat cells (de novo expression) increased transcription of mitochondrial electron transport chain genes, elevated ATP production, decreased rectified K+ channel currents, and increased cell proliferation and motility; these functional changes were inhibited by the TSPO ligand PK11195.","method":"Stable TSPO transfection into TSPO-deficient cells, RT-qPCR, radioligand binding, immunocytochemistry, patch-clamp electrophysiology, ATP assay, proliferation/motility assays","journal":"Cell Cycle","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — gain-of-function with multiple orthogonal readouts and pharmacological confirmation, single lab","pmids":["28103132"],"is_preprint":false},{"year":2021,"finding":"Deletion of TSPO in mouse retina caused elevated levels of cholesterol, triglycerides, and phospholipids with perturbed cholesterol efflux in RPE cells, downregulation of cholesterol-associated genes (Nr1h3, Abca1, Abcg1, Cyp27a1, Cyp46a1), increased pro-inflammatory cytokines, and microglial activation, demonstrating a role for TSPO in retinal cholesterol homeostasis.","method":"Tspo knockout mouse retina, histology/immunohistochemistry, biochemical lipid assays, gene expression profiling, cytokine measurement","journal":"Cells","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — knockout mouse model with multiple orthogonal biochemical readouts, single lab","pmids":["34831289"],"is_preprint":false},{"year":2021,"finding":"TSPO-deficient microglia (in APP/PS1 background) showed a significant decrease in phagocytic capacity for Aβ peptides and latex beads, and generated more pro-inflammatory cytokines (TNF-α, IL-1β) in response to Aβ; APP/PS1 mice lacking TSPO had higher levels of Aβ1-40, Aβ1-42 and more amyloid plaques, indicating that TSPO is required for normal microglial phagocytic clearance of amyloid.","method":"TSPO knockout in APP/PS1 mouse model, primary microglial culture with phagocytosis assays (Aβ and latex beads), ELISA for cytokines and Aβ levels, amyloid plaque quantification","journal":"Neurobiology of Aging","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — knockout in disease model plus in vitro mechanistic validation, single lab","pmids":["34340010"],"is_preprint":false},{"year":2012,"finding":"TSPO ligands (PK11195, Ro5-4864) induced redistribution of intracellular cholesterol into lipid droplets, blocked cholesterol esterification, increased cholesterol efflux, caused mitochondrial shrinkage and depolarisation, and depleted acidic vesicles in astrocytes and fibroblasts; these effects were reproduced by diazepam but not by clonazepam (GABAA-selective), linking the effects specifically to TSPO binding.","method":"Fluorescent cholesterol analogue (NBD-cholesterol) imaging, [3H]cholesterol efflux assay, MTT assay, immunocytochemistry, pharmacological specificity controls","journal":"Neuropharmacology","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — pharmacological approach with multiple cellular readouts and receptor-specificity controls, replicated in two cell types, single lab","pmids":["17631921"],"is_preprint":false},{"year":1993,"finding":"TSPO (mDRC/PBR) ligands of the 2-arylindole-3-acetamide class stimulated pregnenolone formation from mitochondria of C6-2B glioma cells with an EC50 of ~3 nM, directly linking TSPO pharmacology to mitochondrial neurosteroid biosynthesis.","method":"In vitro steroid synthesis assay (C6-2B glioma cell mitochondria), radioligand displacement ([3H]4'-chlorodiazepam binding), structure-activity relationship studies","journal":"Journal of Medicinal Chemistry","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — direct in vitro mitochondrial steroid synthesis assay with SAR confirmation, single lab","pmids":["8411007"],"is_preprint":false},{"year":2004,"finding":"RNAi knockdown of TSPO (PBR) in human fibroblasts and fibrosarcoma cells did not affect cell proliferation and did not influence the anti-proliferative effect of PK11195 or Ro5-4864, demonstrating that these ligands inhibit proliferation through PBR-independent mechanisms in mesenchymal cells.","method":"RNAi knockdown, cell proliferation assay, cell cycle analysis (G0/G1 arrest), ERK/c-Jun activation assays","journal":"Biochemical Pharmacology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — specific genetic knockdown with functional proliferation readout; notable as a negative finding establishing PBR-independence in this cell type","pmids":["15130769"],"is_preprint":false},{"year":2020,"finding":"Chemogenetic (DREADDs), physiological (novel environment), and pharmacological (amphetamine) stimulation of neuronal activity consistently increased TSPO gene and protein levels in neurons but not in microglia or astrocytes in the adult mouse brain, as confirmed by single-cell RNA sequencing and confocal microscopy.","method":"Single-cell RNA sequencing, DREADDs chemogenetics, pharmacological stimulation, confocal laser scanning microscopy, TSPO mRNA/protein quantification","journal":"Molecular Psychiatry","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — three orthogonal stimulation paradigms with single-cell resolution expression analysis, single lab","pmids":["32398717"],"is_preprint":false},{"year":2020,"finding":"Amhr2-Cre-mediated global Tspo knockout mice showed delayed preimplantation embryonic development (66.7% of blastocysts at E3.5–4.5 showed delayed morphology), disturbances in neutral lipid homeostasis, reduced intratesticular and circulating testosterone, and transcriptome changes in adrenal glands and lungs including upregulation of cholesterol-binding and transfer proteins as compensatory responses.","method":"Conditional/global Tspo knockout (Amhr2-Cre), embryo morphology analysis, testosterone/corticosterone ELISA, lipid analysis, RNA-sequencing","journal":"Journal of the Endocrine Society","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — genetic KO model with multiple physiological and transcriptomic readouts, single lab","pmids":["32099945"],"is_preprint":false},{"year":2019,"finding":"Diazepam activated TSPO (PBR) in melanocytes, increasing intracellular cAMP and PKA-mediated CREB phosphorylation, which in turn upregulated tyrosinase, MITF, Rab27a, Myosin Va, Rab17, and Cdc42, enhancing melanin synthesis, melanocyte dendricity, and melanosome transport/capture at dendrite tips.","method":"Masson-Fontana silver staining, scanning electron microscopy, immunocytochemistry, western blot, pharmacological PBR activation","journal":"International Journal of Biochemistry & Cell Biology","confidence":"Low","confidence_rationale":"Tier 3 / Weak — pharmacological approach only (no genetic KO/KD of PBR to confirm on-target effect), single lab, single primary method for each endpoint","pmids":["31561018"],"is_preprint":false}],"current_model":"TSPO is a five-transmembrane-helix outer mitochondrial membrane protein that forms a tightly interacting dimer (resolved by crystal structure) and adopts a rigid five-helix bundle when bound to ligands such as PK11195 but is conformationally dynamic in their absence; it interacts with VDAC, ANT, and p62/SQSTM1 to influence mitochondrial permeability transition, ROS production, and autophagy/mitophagy, and it regulates mitochondrial bioenergetics (fatty acid oxidation, OXPHOS, ATP production) and microglial phagocytic function, while its long-presumed essential role in cholesterol transport for steroidogenesis has been directly refuted by multiple TSPO knockout models showing normal steroid levels; TSPO also modulates neurosteroid synthesis pharmacologically, controls NOX1-dependent ROS in retinal phagocytes, promotes microglial spine engulfment upon diazepam binding, and is required for hypothalamic tanycyte lipophagy and energy balance, with its expression upregulated by neuronal activity and in activated glial cells."},"narrative":{"mechanistic_narrative":"TSPO is an outer mitochondrial membrane protein that functions as a regulator of mitochondrial bioenergetics and metabolic state rather than as an essential cholesterol transporter [PMID:26741196, PMID:25406832]. Atomic-resolution structures define it as a tightly interacting dimer that adopts a rigid five-helix bundle when bound to ligands such as PK11195 but samples multiple conformations with local unfolding near the ligand-binding site in their absence, and that harbors an endogenous porphyrin-binding site whose cholesterol interaction is altered by the human Ala147Thr polymorphism [PMID:25635101, PMID:26394723, PMID:26551694]. Genetic ablation shifts mitochondrial substrate utilization toward fatty acid oxidation and raises ROS without changing oxygen consumption [PMID:26741196], while loss of TSPO lowers ATP production and impairs OXPHOS and glycolysis in microglia [PMID:25406832, PMID:32695005]; multiple knockout models show normal cholesterol transport, pregnenolone levels, and steroidogenesis, directly refuting the long-held essential steroidogenic role [PMID:25406832]. Through this metabolic control, TSPO is required for microglial activation and phagocytic function, including amyloid-β clearance, and drives NOX1-dependent neurotoxic ROS in retinal phagocytes during neovascular degeneration [PMID:32695005, PMID:34340010, PMID:32483169]. TSPO also governs hypothalamic tanycyte lipophagy and energy balance via an AMPK-dependent pathway and interacts with p62/SQSTM1 to modulate autophagy and Nrf2-dependent antioxidant signaling in tumor cells [PMID:31469345, PMID:36994647]. Its expression is induced by neuronal activity in neurons, and diazepam acting through TSPO—not GABAA receptors—promotes microglial engulfment of dendritic spines [PMID:32398717, PMID:35228700]. Pharmacologically, TSPO ligands stimulate mitochondrial neurosteroid (pregnenolone) synthesis and redistribute intracellular cholesterol [PMID:8411007, PMID:17631921].","teleology":[{"year":1992,"claim":"Established that TSPO is not exclusively mitochondrial, with a plasma-membrane pool in steroidogenic adrenal cells, hinting at functions beyond the canonical mitochondrial location.","evidence":"Anti-peptide immunocytochemistry and confocal microscopy with 3D reconstruction in mouse adrenal cortex","pmids":["1332905"],"confidence":"Medium","gaps":["Functional role of the plasma-membrane pool not defined","Single method, single lab"]},{"year":1993,"claim":"Linked TSPO pharmacology directly to mitochondrial neurosteroidogenesis by showing TSPO ligands stimulate pregnenolone formation, framing TSPO as a regulator of steroid synthesis.","evidence":"In vitro mitochondrial steroid synthesis assay in C6-2B glioma cells with radioligand displacement and SAR studies","pmids":["8411007"],"confidence":"Medium","gaps":["Pharmacological correlation does not establish that TSPO protein is mechanistically required","No genetic loss-of-function control"]},{"year":2003,"claim":"Provided a signaling rationale for TSPO in steroidogenesis by identifying PAP7 as an AKAP bridging cAMP/PKA to TSPO-mediated cholesterol transport.","evidence":"Phage display, co-immunoprecipitation, antisense knockdown, and steroid production assay","pmids":["12943713"],"confidence":"Medium","gaps":["Knockdown-based, later contradicted by knockout steroid phenotypes","Single lab"]},{"year":2002,"claim":"Loss-of-function (antisense) and competitive peptide antagonism supported a requirement for endogenous ligand–TSPO interaction in hormone-stimulated steroid formation.","evidence":"Antisense knockdown and phage-display peptide antagonist in MA-10 Leydig cells with steroid assays","pmids":["12530641"],"confidence":"Medium","gaps":["Conclusions later challenged by viable steroid-normal knockout mice","Knockdown off-target effects not excluded"]},{"year":2004,"claim":"Showed that anti-proliferative effects of TSPO ligands in mesenchymal cells are PBR-independent, separating ligand pharmacology from receptor function.","evidence":"RNAi knockdown with proliferation, cell-cycle, and ERK/c-Jun assays in fibroblasts and fibrosarcoma cells","pmids":["15130769"],"confidence":"Medium","gaps":["Negative result specific to mesenchymal cells","Does not address TSPO function in other lineages"]},{"year":2012,"claim":"Demonstrated TSPO ligands remodel intracellular cholesterol distribution and mitochondrial state, with GABAA-selective controls assigning the effects to TSPO.","evidence":"NBD-cholesterol imaging, cholesterol efflux assays, and pharmacological specificity controls (diazepam vs clonazepam) in astrocytes and fibroblasts","pmids":["17631921"],"confidence":"Medium","gaps":["Pharmacology-only; no genetic confirmation","Single lab"]},{"year":2014,"claim":"Refuted the essential cholesterol-transport/steroidogenesis model by showing global Tspo knockout mice are viable with normal steroids, while revealing reduced microglial ATP—redirecting the field toward bioenergetics.","evidence":"Global Tspo knockout mouse with PET imaging, cholesterol/pregnenolone/protoporphyrin assays, and microglial ATP measurement","pmids":["25406832"],"confidence":"High","gaps":["Compensatory adaptation in knockout not fully resolved","Mechanism linking TSPO to ATP not defined here"]},{"year":2014,"claim":"Defined the ligand-dependent conformational behaviour of TSPO, showing a rigid five-helix bundle when PK11195-bound versus dynamic exchange and local unfolding when unbound.","evidence":"Solution-state NMR structure of mouse TSPO with PK11195 and conformational dynamics analysis","pmids":["26394723","26551694"],"confidence":"High","gaps":["Functional consequence of conformational dynamics in vivo unclear","Endogenous ligand state not captured"]},{"year":2015,"claim":"Provided atomic-resolution architecture of TSPO, defining the dimer, an endogenous porphyrin-binding site, and the structural impact of the human Ala147Thr polymorphism on cholesterol binding.","evidence":"X-ray crystallography of Rhodobacter TSPO in lipidic cubic phase with mutagenesis mimicking the human polymorphism","pmids":["25635101"],"confidence":"High","gaps":["Bacterial ortholog; human-specific features inferred via mutagenesis","Cholesterol-transport function not demonstrated structurally"]},{"year":2016,"claim":"Established a direct metabolic function: TSPO loss shifts mitochondrial substrate use from glucose to fatty acids with elevated FAO and ROS, defining TSPO as a bioenergetic regulator.","evidence":"CRISPR/Cas9 knockout in MA-10 cells with Seahorse flux analysis, gene profiling, and corroboration in Tspo-/- mouse adrenal","pmids":["26741196"],"confidence":"High","gaps":["Molecular mechanism coupling TSPO to substrate choice unknown","Direct lipid-handling activity not shown"]},{"year":2017,"claim":"Gain-of-function showed de novo TSPO expression upregulates ETC genes, raises ATP, and increases proliferation/motility, reinforcing a bioenergetic and growth-promoting role.","evidence":"Stable TSPO transfection into TSPO-low Jurkat cells with RT-qPCR, patch-clamp, ATP and proliferation/motility assays, plus PK11195 inhibition","pmids":["28103132"],"confidence":"Medium","gaps":["Single cell system","Mechanism connecting TSPO to ETC gene transcription unresolved"]},{"year":2019,"claim":"Connected TSPO to organismal energy balance by showing tanycytic TSPO loss triggers AMPK-dependent lipophagy, reducing food intake and raising energy expenditure.","evidence":"Tanycyte-specific Rax-Cre knockout with ICV PK11195, metabolic cage studies, and lipophagy/AMPK pathway analysis","pmids":["31469345"],"confidence":"Medium","gaps":["Direct molecular target of TSPO in lipophagy not identified","Single lab"]},{"year":2020,"claim":"Showed TSPO controls microglial activation through mitochondrial metabolism, with deficiency suppressing OXPHOS, glycolysis, membrane potential, and ATP.","evidence":"Knockout-derived primary microglia and siRNA knockdown with LPS/IL-4 activation and Seahorse metabolic analysis","pmids":["32695005"],"confidence":"Medium","gaps":["Mechanism coupling TSPO to metabolic flux unresolved","Single lab"]},{"year":2020,"claim":"Identified neuronal activity as a driver of TSPO expression, refining interpretation of TSPO as a glial-activation imaging marker.","evidence":"Single-cell RNA-seq with DREADD chemogenetics, novel environment, and amphetamine stimulation plus confocal microscopy","pmids":["32398717"],"confidence":"Medium","gaps":["Functional consequence of neuronal TSPO induction unknown","Single lab"]},{"year":2020,"claim":"Extended TSPO loss-of-function phenotypes to reproduction and lipid homeostasis, with delayed embryonic development and reduced testosterone alongside compensatory cholesterol-transport gene upregulation.","evidence":"Amhr2-Cre Tspo knockout with embryo morphology, testosterone ELISA, lipid analysis, and RNA-seq","pmids":["32099945"],"confidence":"Medium","gaps":["Testosterone reduction contrasts with normal steroids in other knockouts","Compensatory mechanisms not mechanistically dissected"]},{"year":2020,"claim":"Placed TSPO upstream of NOX1-dependent neurotoxic ROS in retinal phagocytes, defining a controllable node in microglial reactivity and neovascular pathology.","evidence":"Cx3cr1-CreERT2 conditional knockout, XBD173 ligand treatment, and genetic epistasis with NADPH oxidase-deficient mice in a laser-induced CNV model","pmids":["32483169"],"confidence":"High","gaps":["Biochemical link between TSPO and NOX1 not resolved","Generalizability beyond retina untested"]},{"year":2021,"claim":"Demonstrated TSPO is required for microglial phagocytic clearance of amyloid-β, with deficiency worsening plaque burden and inflammation in APP/PS1 mice.","evidence":"TSPO knockout in APP/PS1 background with primary microglial phagocytosis assays, cytokine ELISA, and plaque quantification","pmids":["34340010"],"confidence":"Medium","gaps":["Mechanistic link from TSPO metabolism to phagocytosis not defined","Single lab"]},{"year":2021,"claim":"Revealed a role in retinal lipid homeostasis, with TSPO deletion elevating cholesterol/lipids, perturbing efflux, and inducing inflammation.","evidence":"Tspo knockout mouse retina with histology, biochemical lipid assays, gene profiling, and cytokine measurement","pmids":["34831289"],"confidence":"Medium","gaps":["Direct lipid-transport activity not demonstrated","Cell-type contribution within retina unresolved"]},{"year":2022,"claim":"Showed diazepam-induced cognitive and spine deficits act through TSPO rather than GABAA receptors by enhancing microglial phagocytosis of synaptic material, reframing benzodiazepine neurotoxicity.","evidence":"TSPO-specific genetic manipulation, two-photon spine imaging, microglial phagocytosis assays, and PET in mice","pmids":["35228700"],"confidence":"High","gaps":["Signaling cascade from TSPO ligand binding to phagocytosis unresolved","Endogenous ligand for this pathway unknown"]},{"year":2023,"claim":"Defined a physical TSPO–p62/SQSTM1 interaction that blocks autophagy and activates Nrf2 antioxidant and PD-L1 immune-evasion programs in tumor cells.","evidence":"Co-immunoprecipitation with gain/loss-of-function, autophagy assays, and Nrf2/KEAP1/p62 pathway analysis in HCC models","pmids":["36994647"],"confidence":"Medium","gaps":["Co-IP without reciprocal structural validation of the interface","Interaction generality beyond HCC untested"]},{"year":null,"claim":"The molecular activity that couples TSPO's structural dynamics and ligand binding to its downstream control of mitochondrial substrate use, ROS, autophagy, and phagocytosis, and the identity of its physiological endogenous ligand, remain undefined.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No defined enzymatic or transport activity for TSPO","Endogenous ligand mediating in vivo functions unidentified","Mechanistic chain from TSPO to bioenergetic/phagocytic outputs not reconstituted"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0008289","term_label":"lipid binding","supporting_discovery_ids":[0,15,13]},{"term_id":"GO:0098772","term_label":"molecular function regulator activity","supporting_discovery_ids":[2,7,9]}],"localization":[{"term_id":"GO:0005739","term_label":"mitochondrion","supporting_discovery_ids":[2,6,16]},{"term_id":"GO:0005886","term_label":"plasma membrane","supporting_discovery_ids":[6]}],"pathway":[{"term_id":"R-HSA-1430728","term_label":"Metabolism","supporting_discovery_ids":[2,9,13]},{"term_id":"R-HSA-168256","term_label":"Immune System","supporting_discovery_ids":[7,8,14]},{"term_id":"R-HSA-9612973","term_label":"Autophagy","supporting_discovery_ids":[9,11]}],"complexes":[],"partners":["VDAC","P62/SQSTM1","PAP7"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"P30536","full_name":"Translocator protein","aliases":["Mitochondrial benzodiazepine receptor","PKBS","Peripheral-type benzodiazepine receptor","PBR"],"length_aa":169,"mass_kda":18.8,"function":"Can bind protoporphyrin IX and may play a role in the transport of porphyrins and heme (By similarity). Promotes the transport of cholesterol across mitochondrial membranes and may play a role in lipid metabolism (PubMed:24814875), but its precise physiological role is controversial. It is apparently not required for steroid hormone biosynthesis. Was initially identified as peripheral-type benzodiazepine receptor; can also bind isoquinoline carboxamides (PubMed:1847678)","subcellular_location":"Mitochondrion membrane","url":"https://www.uniprot.org/uniprotkb/P30536/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/TSPO","classification":"Not Classified","n_dependent_lines":0,"n_total_lines":1208,"dependency_fraction":0.0},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[],"url":"https://opencell.sf.czbiohub.org/search/TSPO","total_profiled":1310},"omim":[{"mim_id":"620456","title":"DYSTONIA 22, ADULT-ONSET; DYT22AO","url":"https://www.omim.org/entry/620456"},{"mim_id":"620453","title":"DYSTONIA 22, JUVENILE-ONSET; DYT22JO","url":"https://www.omim.org/entry/620453"},{"mim_id":"619409","title":"TRANSLOCATOR PROTEIN 2; TSPO2","url":"https://www.omim.org/entry/619409"},{"mim_id":"616992","title":"CHROMOSOME 8 OPEN READING FRAME 17; C8ORF17","url":"https://www.omim.org/entry/616992"},{"mim_id":"613558","title":"DEAFNESS, AUTOSOMAL DOMINANT 51; DFNA51","url":"https://www.omim.org/entry/613558"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Supported","locations":[{"location":"Mitochondria","reliability":"Supported"},{"location":"Vesicles","reliability":"Additional"},{"location":"Cytosol","reliability":"Additional"}],"tissue_specificity":"Tissue enhanced","tissue_distribution":"Detected in all","driving_tissues":[{"tissue":"esophagus","ntpm":704.4}],"url":"https://www.proteinatlas.org/search/TSPO"},"hgnc":{"alias_symbol":["PBR","MBR","PKBS","mDRC","DBI","IBP","pk18","TSPO1"],"prev_symbol":["BZRP"]},"alphafold":{"accession":"P30536","domains":[{"cath_id":"1.20.1260.100","chopping":"5-31_48-159","consensus_level":"high","plddt":67.2176,"start":5,"end":159}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/P30536","model_url":"https://alphafold.ebi.ac.uk/files/AF-P30536-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-P30536-F1-predicted_aligned_error_v6.png","plddt_mean":66.31},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=TSPO","jax_strain_url":"https://www.jax.org/strain/search?query=TSPO"},"sequence":{"accession":"P30536","fasta_url":"https://rest.uniprot.org/uniprotkb/P30536.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/P30536/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/P30536"}},"corpus_meta":[{"pmid":"8045426","id":"PMC_8045426","title":"Small mobilizable multi-purpose cloning vectors derived from the Escherichia coli plasmids pK18 and pK19: selection of defined deletions in the chromosome of Corynebacterium glutamicum.","date":"1994","source":"Gene","url":"https://pubmed.ncbi.nlm.nih.gov/8045426","citation_count":2370,"is_preprint":false},{"pmid":"21119734","id":"PMC_21119734","title":"Translocator protein (18 kDa) (TSPO) as a therapeutic target for neurological and psychiatric disorders.","date":"2010","source":"Nature reviews. 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Germany)","url":"https://pubmed.ncbi.nlm.nih.gov/26394723","citation_count":26,"is_preprint":false},{"pmid":"38997465","id":"PMC_38997465","title":"PET imaging of neuroinflammation: any credible alternatives to TSPO yet?","date":"2024","source":"Molecular psychiatry","url":"https://pubmed.ncbi.nlm.nih.gov/38997465","citation_count":26,"is_preprint":false},{"pmid":"24900292","id":"PMC_24900292","title":"TSPO 18 kDa (PBR) Targeted Photosensitizers for Cancer Imaging (PET) and PDT.","date":"2010","source":"ACS medicinal chemistry letters","url":"https://pubmed.ncbi.nlm.nih.gov/24900292","citation_count":25,"is_preprint":false},{"pmid":"29211020","id":"PMC_29211020","title":"An Updated View of Translocator Protein (TSPO).","date":"2017","source":"International journal of molecular sciences","url":"https://pubmed.ncbi.nlm.nih.gov/29211020","citation_count":24,"is_preprint":false},{"pmid":"37939554","id":"PMC_37939554","title":"Designed bacteria based on natural pbr operons for detecting and detoxifying environmental lead: A mini-review.","date":"2023","source":"Ecotoxicology and environmental safety","url":"https://pubmed.ncbi.nlm.nih.gov/37939554","citation_count":24,"is_preprint":false},{"pmid":"39477764","id":"PMC_39477764","title":"Emerging TSPO-PET Radiotracers for Imaging Neuroinflammation: A Critical Analysis.","date":"2024","source":"Seminars in nuclear medicine","url":"https://pubmed.ncbi.nlm.nih.gov/39477764","citation_count":24,"is_preprint":false},{"pmid":"27599163","id":"PMC_27599163","title":"Translocator protein (TSPO) ligands for the diagnosis or treatment of neurodegenerative diseases: a patent review (2010 - 2015; part 2).","date":"2016","source":"Expert opinion on therapeutic patents","url":"https://pubmed.ncbi.nlm.nih.gov/27599163","citation_count":24,"is_preprint":false},{"pmid":"26551690","id":"PMC_26551690","title":"Targeting mitochondrial energy metabolism with TSPO ligands.","date":"2015","source":"Biochemical Society 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(TSPO).","date":"2015","source":"Pharmacological research","url":"https://pubmed.ncbi.nlm.nih.gov/25882248","citation_count":21,"is_preprint":false},{"pmid":"34340010","id":"PMC_34340010","title":"TSPO deficiency accelerates amyloid pathology and neuroinflammation by impairing microglial phagocytosis.","date":"2021","source":"Neurobiology of aging","url":"https://pubmed.ncbi.nlm.nih.gov/34340010","citation_count":21,"is_preprint":false},{"pmid":"32099945","id":"PMC_32099945","title":"Amhr2-Cre-Mediated Global Tspo Knockout.","date":"2020","source":"Journal of the Endocrine Society","url":"https://pubmed.ncbi.nlm.nih.gov/32099945","citation_count":20,"is_preprint":false},{"pmid":"39275061","id":"PMC_39275061","title":"TSPO Radioligands for Neuroinflammation: An Overview.","date":"2024","source":"Molecules (Basel, Switzerland)","url":"https://pubmed.ncbi.nlm.nih.gov/39275061","citation_count":20,"is_preprint":false},{"pmid":"31561018","id":"PMC_31561018","title":"Diazepam enhances melanogenesis, melanocyte dendricity and melanosome transport via the PBR/cAMP/PKA pathway.","date":"2019","source":"The international journal of biochemistry & cell biology","url":"https://pubmed.ncbi.nlm.nih.gov/31561018","citation_count":20,"is_preprint":false},{"pmid":"36432736","id":"PMC_36432736","title":"18F-Radiolabeled Translocator Protein (TSPO) PET Tracers: Recent Development of TSPO Radioligands and Their Application to PET Study.","date":"2022","source":"Pharmaceutics","url":"https://pubmed.ncbi.nlm.nih.gov/36432736","citation_count":20,"is_preprint":false},{"pmid":"34831289","id":"PMC_34831289","title":"Deletion of TSPO Causes Dysregulation of Cholesterol Metabolism in Mouse Retina.","date":"2021","source":"Cells","url":"https://pubmed.ncbi.nlm.nih.gov/34831289","citation_count":20,"is_preprint":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":44721,"output_tokens":5464,"usd":0.108062,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":14100,"output_tokens":5652,"usd":0.1059,"stage2_stop_reason":"end_turn"},"total_usd":0.213962,"stage1_batch_id":"msgbatch_017qqVz33Ga63SCDwzb35XPb","stage2_batch_id":"msgbatch_01Scr2Ei9x4HJMiRGxwrmvLK","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2015,\n      \"finding\": \"Crystal structures of TSPO from Rhodobacter sphaeroides at 1.8, 2.4, and 2.5 Å resolution (lipidic cubic phase) revealed a tightly interacting dimer, the binding site of an endogenous porphyrin ligand, and conformational effects of the human Ala147→Thr147 polymorphism on cholesterol binding.\",\n      \"method\": \"X-ray crystallography (lipidic cubic phase), site-directed mutagenesis to mimic human polymorphism\",\n      \"journal\": \"Science\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — atomic-resolution crystal structures with multiple resolutions, mutagenesis validation, and independent structural confirmation\",\n      \"pmids\": [\"25635101\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"NMR structure of mouse TSPO in complex with PK11195 showed a rigid five-helix bundle when bound to the ligand; in the absence of PK11195, TSPO exchanges between multiple conformations with extensive motions on pico- to microsecond timescales and local unfolding near the ligand-binding site.\",\n      \"method\": \"NMR spectroscopy (solution-state), ligand binding/unbinding studies\",\n      \"journal\": \"Science / Chemistry (Weinheim)\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — atomic-resolution NMR structure with ligand, conformational dynamics characterised by multiple NMR parameters, replicated across two related papers\",\n      \"pmids\": [\"26394723\", \"26551694\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"CRISPR/Cas9 knockout of TSPO in steroidogenic MA-10 Leydig cells caused a shift in mitochondrial substrate utilisation from glucose to fatty acids, with significantly higher fatty acid oxidation (FAO) and increased reactive oxygen species production, but no change in oxygen consumption rate, membrane potential, or proton leak; consistent upregulation of FAO genes was found in adrenal glands of global Tspo−/− mice.\",\n      \"method\": \"CRISPR/Cas9 knockout, Seahorse metabolic flux analysis, gene expression profiling, global TSPO knockout mouse model\",\n      \"journal\": \"Endocrinology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — CRISPR KO in vitro corroborated by in vivo knockout mouse, multiple orthogonal metabolic readouts\",\n      \"pmids\": [\"26741196\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"Global C57BL/6 Tspo knockout mice are viable with normal growth, lifespan, cholesterol transport, blood pregnenolone concentration, protoporphyrin IX metabolism, fertility, and behaviour, directly challenging the model that TSPO is essential for cholesterol transport and steroidogenesis. However, microglia from TSPO knockouts produced significantly less ATP, indicating reduced metabolic activity.\",\n      \"method\": \"Global gene knockout mouse model, PET imaging with PK11195/CLINDE/PBR111, biochemical assays (cholesterol, pregnenolone, protoporphyrin IX), ATP measurement in isolated microglia\",\n      \"journal\": \"Nature Communications\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — complete knockout animal model with multiple orthogonal biochemical and functional readouts, published in peer-reviewed journal\",\n      \"pmids\": [\"25406832\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2003,\n      \"finding\": \"TSPO (PBR) interacts with PAP7, a protein that also binds the PKA regulatory subunit RIα; PAP7 is localized to Golgi and mitochondria. Inhibition of PAP7 expression reduced hormone-induced cholesterol transport into mitochondria and decreased steroid formation, placing PAP7 as an AKAP linking cAMP/PKA signalling to TSPO-mediated cholesterol transport.\",\n      \"method\": \"Protein interaction identification (phage display, co-immunoprecipitation), antisense oligonucleotide knockdown, steroid production assay\",\n      \"journal\": \"Journal of Steroid Biochemistry and Molecular Biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reciprocal protein interaction plus functional knockdown readout, single lab\",\n      \"pmids\": [\"12943713\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2002,\n      \"finding\": \"Antisense knockdown of TSPO (PBR) in MA-10 Leydig cells reduced PBR protein levels and inhibited hormone-stimulated steroid formation; a 7-mer competitive PBR peptide antagonist identified by phage display also inhibited benzodiazepine- and hormone-stimulated steroid production when transduced into Leydig cells, supporting the requirement for endogenous PBR agonist–receptor interaction in steroidogenesis.\",\n      \"method\": \"Antisense oligonucleotide knockdown, phage display peptide antagonist, steroid production assay\",\n      \"journal\": \"Endocrine Research\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — loss-of-function (antisense) plus orthogonal peptide antagonist approach, single lab\",\n      \"pmids\": [\"12530641\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1992,\n      \"finding\": \"Immunocytochemistry and confocal microscopy with 3D reconstruction in mouse adrenal cortex demonstrated that a subset of PBR/TSPO localises to the plasma membrane in zona fasciculata cells, in addition to the mitochondrial pool, suggesting functions not restricted to mitochondria.\",\n      \"method\": \"Anti-peptide immunocytochemistry, biotin-streptavidin peroxidase staining, confocal microscopy with 3D reconstruction\",\n      \"journal\": \"Molecular and Cellular Endocrinology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — direct subcellular localisation by confocal microscopy with 3D reconstruction, single lab, single method\",\n      \"pmids\": [\"1332905\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"TSPO deficiency (knockout mice and siRNA knockdown cell line) significantly inhibited microglial activation induced by LPS or IL-4, decreased mitochondrial membrane potential and ATP production, and suppressed both mitochondrial OXPHOS and glycolysis, demonstrating that TSPO regulates microglial activation through control of mitochondrial metabolism.\",\n      \"method\": \"TSPO knockout mouse-derived primary microglia, siRNA knockdown cell line, LPS/IL-4 activation assays, Seahorse metabolic analysis, mitochondrial membrane potential measurement, ATP assay\",\n      \"journal\": \"Frontiers in Pharmacology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — two genetic loss-of-function systems (KO mice + siRNA) with multiple metabolic readouts, single lab\",\n      \"pmids\": [\"32695005\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"Conditional deletion of TSPO in retinal microglia (Cx3cr1-CreERT2:TSPOfl/fl) or treatment with the TSPO ligand XBD173 prevented microglial/phagocyte reactivity and subsequent neoangiogenesis in the laser-induced neovascular AMD model. Using NADPH oxidase-deficient mice, TSPO was identified as a key regulator of NOX1-dependent neurotoxic ROS production in the retina.\",\n      \"method\": \"Conditional knockout mouse (Cx3cr1-CreERT2:TSPOfl/fl), pharmacological ligand treatment (XBD173), NADPH oxidase-deficient mouse strains (genetic epistasis), laser-induced choroidal neovascularisation model\",\n      \"journal\": \"Nature Communications\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — conditional cell-type-specific KO combined with genetic epistasis using multiple NOX-deficient mouse lines, published in high-tier journal\",\n      \"pmids\": [\"32483169\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"Tanycyte-specific deletion of TSPO (Rax-Cre) in the hypothalamus and intracerebroventricular administration of PK11195 reduced food intake and elevated energy expenditure in high-fat diet conditions; ablation of tanycytic TSPO elicited AMPK-dependent lipophagy, breaking down lipid droplets to free fatty acids and elevating ATP, linking TSPO to hypothalamic lipid sensing and energy balance via autophagy regulation.\",\n      \"method\": \"Tanycyte-specific conditional knockout (Rax-Cre), intracerebroventricular ligand injection, metabolic cage studies, lipophagy/autophagy assays, AMPK pathway analysis\",\n      \"journal\": \"Autophagy\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — cell-type-specific KO with mechanistic pathway dissection (AMPK-lipophagy), single lab\",\n      \"pmids\": [\"31469345\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"Diazepam impaired structural plasticity of dendritic spines and caused cognitive impairment in mice via TSPO (not GABAA receptors), altering microglial morphology and enhancing microglial phagocytosis of synaptic material (spine engulfment); this was demonstrated using TSPO-specific genetic approaches.\",\n      \"method\": \"In vivo mouse model, TSPO-specific genetic manipulation (knockouts/ligands), two-photon microscopy of spine dynamics, microglial phagocytosis assays, PET imaging\",\n      \"journal\": \"Nature Neuroscience\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — genetic dissection of TSPO vs. GABAA receptor contributions with multiple in vivo functional readouts, published in high-tier journal\",\n      \"pmids\": [\"35228700\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"TSPO directly interacts with p62/SQSTM1 in hepatocellular carcinoma cells, interfering with autophagy and causing p62 accumulation; accumulated p62 competes with KEAP1, preventing KEAP1-mediated proteasomal degradation of Nrf2, thereby activating Nrf2-dependent antioxidant defence to inhibit ferroptosis and upregulating PD-L1 expression to promote immune evasion.\",\n      \"method\": \"Co-immunoprecipitation (TSPO–p62 interaction), gain- and loss-of-function experiments, autophagy assays, Nrf2/KEAP1/p62 pathway analysis, PD-L1 expression measurement, in vitro and in vivo tumour models\",\n      \"journal\": \"Advanced Science\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — Co-IP plus functional pathway dissection with gain/loss of function, single lab\",\n      \"pmids\": [\"36994647\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"Stable transfection of TSPO into TSPO-low Jurkat cells (de novo expression) increased transcription of mitochondrial electron transport chain genes, elevated ATP production, decreased rectified K+ channel currents, and increased cell proliferation and motility; these functional changes were inhibited by the TSPO ligand PK11195.\",\n      \"method\": \"Stable TSPO transfection into TSPO-deficient cells, RT-qPCR, radioligand binding, immunocytochemistry, patch-clamp electrophysiology, ATP assay, proliferation/motility assays\",\n      \"journal\": \"Cell Cycle\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — gain-of-function with multiple orthogonal readouts and pharmacological confirmation, single lab\",\n      \"pmids\": [\"28103132\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"Deletion of TSPO in mouse retina caused elevated levels of cholesterol, triglycerides, and phospholipids with perturbed cholesterol efflux in RPE cells, downregulation of cholesterol-associated genes (Nr1h3, Abca1, Abcg1, Cyp27a1, Cyp46a1), increased pro-inflammatory cytokines, and microglial activation, demonstrating a role for TSPO in retinal cholesterol homeostasis.\",\n      \"method\": \"Tspo knockout mouse retina, histology/immunohistochemistry, biochemical lipid assays, gene expression profiling, cytokine measurement\",\n      \"journal\": \"Cells\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — knockout mouse model with multiple orthogonal biochemical readouts, single lab\",\n      \"pmids\": [\"34831289\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"TSPO-deficient microglia (in APP/PS1 background) showed a significant decrease in phagocytic capacity for Aβ peptides and latex beads, and generated more pro-inflammatory cytokines (TNF-α, IL-1β) in response to Aβ; APP/PS1 mice lacking TSPO had higher levels of Aβ1-40, Aβ1-42 and more amyloid plaques, indicating that TSPO is required for normal microglial phagocytic clearance of amyloid.\",\n      \"method\": \"TSPO knockout in APP/PS1 mouse model, primary microglial culture with phagocytosis assays (Aβ and latex beads), ELISA for cytokines and Aβ levels, amyloid plaque quantification\",\n      \"journal\": \"Neurobiology of Aging\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — knockout in disease model plus in vitro mechanistic validation, single lab\",\n      \"pmids\": [\"34340010\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"TSPO ligands (PK11195, Ro5-4864) induced redistribution of intracellular cholesterol into lipid droplets, blocked cholesterol esterification, increased cholesterol efflux, caused mitochondrial shrinkage and depolarisation, and depleted acidic vesicles in astrocytes and fibroblasts; these effects were reproduced by diazepam but not by clonazepam (GABAA-selective), linking the effects specifically to TSPO binding.\",\n      \"method\": \"Fluorescent cholesterol analogue (NBD-cholesterol) imaging, [3H]cholesterol efflux assay, MTT assay, immunocytochemistry, pharmacological specificity controls\",\n      \"journal\": \"Neuropharmacology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — pharmacological approach with multiple cellular readouts and receptor-specificity controls, replicated in two cell types, single lab\",\n      \"pmids\": [\"17631921\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1993,\n      \"finding\": \"TSPO (mDRC/PBR) ligands of the 2-arylindole-3-acetamide class stimulated pregnenolone formation from mitochondria of C6-2B glioma cells with an EC50 of ~3 nM, directly linking TSPO pharmacology to mitochondrial neurosteroid biosynthesis.\",\n      \"method\": \"In vitro steroid synthesis assay (C6-2B glioma cell mitochondria), radioligand displacement ([3H]4'-chlorodiazepam binding), structure-activity relationship studies\",\n      \"journal\": \"Journal of Medicinal Chemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — direct in vitro mitochondrial steroid synthesis assay with SAR confirmation, single lab\",\n      \"pmids\": [\"8411007\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2004,\n      \"finding\": \"RNAi knockdown of TSPO (PBR) in human fibroblasts and fibrosarcoma cells did not affect cell proliferation and did not influence the anti-proliferative effect of PK11195 or Ro5-4864, demonstrating that these ligands inhibit proliferation through PBR-independent mechanisms in mesenchymal cells.\",\n      \"method\": \"RNAi knockdown, cell proliferation assay, cell cycle analysis (G0/G1 arrest), ERK/c-Jun activation assays\",\n      \"journal\": \"Biochemical Pharmacology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — specific genetic knockdown with functional proliferation readout; notable as a negative finding establishing PBR-independence in this cell type\",\n      \"pmids\": [\"15130769\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"Chemogenetic (DREADDs), physiological (novel environment), and pharmacological (amphetamine) stimulation of neuronal activity consistently increased TSPO gene and protein levels in neurons but not in microglia or astrocytes in the adult mouse brain, as confirmed by single-cell RNA sequencing and confocal microscopy.\",\n      \"method\": \"Single-cell RNA sequencing, DREADDs chemogenetics, pharmacological stimulation, confocal laser scanning microscopy, TSPO mRNA/protein quantification\",\n      \"journal\": \"Molecular Psychiatry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — three orthogonal stimulation paradigms with single-cell resolution expression analysis, single lab\",\n      \"pmids\": [\"32398717\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"Amhr2-Cre-mediated global Tspo knockout mice showed delayed preimplantation embryonic development (66.7% of blastocysts at E3.5–4.5 showed delayed morphology), disturbances in neutral lipid homeostasis, reduced intratesticular and circulating testosterone, and transcriptome changes in adrenal glands and lungs including upregulation of cholesterol-binding and transfer proteins as compensatory responses.\",\n      \"method\": \"Conditional/global Tspo knockout (Amhr2-Cre), embryo morphology analysis, testosterone/corticosterone ELISA, lipid analysis, RNA-sequencing\",\n      \"journal\": \"Journal of the Endocrine Society\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genetic KO model with multiple physiological and transcriptomic readouts, single lab\",\n      \"pmids\": [\"32099945\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"Diazepam activated TSPO (PBR) in melanocytes, increasing intracellular cAMP and PKA-mediated CREB phosphorylation, which in turn upregulated tyrosinase, MITF, Rab27a, Myosin Va, Rab17, and Cdc42, enhancing melanin synthesis, melanocyte dendricity, and melanosome transport/capture at dendrite tips.\",\n      \"method\": \"Masson-Fontana silver staining, scanning electron microscopy, immunocytochemistry, western blot, pharmacological PBR activation\",\n      \"journal\": \"International Journal of Biochemistry & Cell Biology\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — pharmacological approach only (no genetic KO/KD of PBR to confirm on-target effect), single lab, single primary method for each endpoint\",\n      \"pmids\": [\"31561018\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"TSPO is a five-transmembrane-helix outer mitochondrial membrane protein that forms a tightly interacting dimer (resolved by crystal structure) and adopts a rigid five-helix bundle when bound to ligands such as PK11195 but is conformationally dynamic in their absence; it interacts with VDAC, ANT, and p62/SQSTM1 to influence mitochondrial permeability transition, ROS production, and autophagy/mitophagy, and it regulates mitochondrial bioenergetics (fatty acid oxidation, OXPHOS, ATP production) and microglial phagocytic function, while its long-presumed essential role in cholesterol transport for steroidogenesis has been directly refuted by multiple TSPO knockout models showing normal steroid levels; TSPO also modulates neurosteroid synthesis pharmacologically, controls NOX1-dependent ROS in retinal phagocytes, promotes microglial spine engulfment upon diazepam binding, and is required for hypothalamic tanycyte lipophagy and energy balance, with its expression upregulated by neuronal activity and in activated glial cells.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"TSPO is an outer mitochondrial membrane protein that functions as a regulator of mitochondrial bioenergetics and metabolic state rather than as an essential cholesterol transporter [#2, #3]. Atomic-resolution structures define it as a tightly interacting dimer that adopts a rigid five-helix bundle when bound to ligands such as PK11195 but samples multiple conformations with local unfolding near the ligand-binding site in their absence, and that harbors an endogenous porphyrin-binding site whose cholesterol interaction is altered by the human Ala147Thr polymorphism [#0, #1]. Genetic ablation shifts mitochondrial substrate utilization toward fatty acid oxidation and raises ROS without changing oxygen consumption [#2], while loss of TSPO lowers ATP production and impairs OXPHOS and glycolysis in microglia [#3, #7]; multiple knockout models show normal cholesterol transport, pregnenolone levels, and steroidogenesis, directly refuting the long-held essential steroidogenic role [#3]. Through this metabolic control, TSPO is required for microglial activation and phagocytic function, including amyloid-\\u03b2 clearance, and drives NOX1-dependent neurotoxic ROS in retinal phagocytes during neovascular degeneration [#7, #14, #8]. TSPO also governs hypothalamic tanycyte lipophagy and energy balance via an AMPK-dependent pathway and interacts with p62/SQSTM1 to modulate autophagy and Nrf2-dependent antioxidant signaling in tumor cells [#9, #11]. Its expression is induced by neuronal activity in neurons, and diazepam acting through TSPO\\u2014not GABAA receptors\\u2014promotes microglial engulfment of dendritic spines [#18, #10]. Pharmacologically, TSPO ligands stimulate mitochondrial neurosteroid (pregnenolone) synthesis and redistribute intracellular cholesterol [#16, #15].\",\n  \"teleology\": [\n    {\n      \"year\": 1992,\n      \"claim\": \"Established that TSPO is not exclusively mitochondrial, with a plasma-membrane pool in steroidogenic adrenal cells, hinting at functions beyond the canonical mitochondrial location.\",\n      \"evidence\": \"Anti-peptide immunocytochemistry and confocal microscopy with 3D reconstruction in mouse adrenal cortex\",\n      \"pmids\": [\"1332905\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Functional role of the plasma-membrane pool not defined\", \"Single method, single lab\"]\n    },\n    {\n      \"year\": 1993,\n      \"claim\": \"Linked TSPO pharmacology directly to mitochondrial neurosteroidogenesis by showing TSPO ligands stimulate pregnenolone formation, framing TSPO as a regulator of steroid synthesis.\",\n      \"evidence\": \"In vitro mitochondrial steroid synthesis assay in C6-2B glioma cells with radioligand displacement and SAR studies\",\n      \"pmids\": [\"8411007\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Pharmacological correlation does not establish that TSPO protein is mechanistically required\", \"No genetic loss-of-function control\"]\n    },\n    {\n      \"year\": 2003,\n      \"claim\": \"Provided a signaling rationale for TSPO in steroidogenesis by identifying PAP7 as an AKAP bridging cAMP/PKA to TSPO-mediated cholesterol transport.\",\n      \"evidence\": \"Phage display, co-immunoprecipitation, antisense knockdown, and steroid production assay\",\n      \"pmids\": [\"12943713\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Knockdown-based, later contradicted by knockout steroid phenotypes\", \"Single lab\"]\n    },\n    {\n      \"year\": 2002,\n      \"claim\": \"Loss-of-function (antisense) and competitive peptide antagonism supported a requirement for endogenous ligand\\u2013TSPO interaction in hormone-stimulated steroid formation.\",\n      \"evidence\": \"Antisense knockdown and phage-display peptide antagonist in MA-10 Leydig cells with steroid assays\",\n      \"pmids\": [\"12530641\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Conclusions later challenged by viable steroid-normal knockout mice\", \"Knockdown off-target effects not excluded\"]\n    },\n    {\n      \"year\": 2004,\n      \"claim\": \"Showed that anti-proliferative effects of TSPO ligands in mesenchymal cells are PBR-independent, separating ligand pharmacology from receptor function.\",\n      \"evidence\": \"RNAi knockdown with proliferation, cell-cycle, and ERK/c-Jun assays in fibroblasts and fibrosarcoma cells\",\n      \"pmids\": [\"15130769\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Negative result specific to mesenchymal cells\", \"Does not address TSPO function in other lineages\"]\n    },\n    {\n      \"year\": 2012,\n      \"claim\": \"Demonstrated TSPO ligands remodel intracellular cholesterol distribution and mitochondrial state, with GABAA-selective controls assigning the effects to TSPO.\",\n      \"evidence\": \"NBD-cholesterol imaging, cholesterol efflux assays, and pharmacological specificity controls (diazepam vs clonazepam) in astrocytes and fibroblasts\",\n      \"pmids\": [\"17631921\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Pharmacology-only; no genetic confirmation\", \"Single lab\"]\n    },\n    {\n      \"year\": 2014,\n      \"claim\": \"Refuted the essential cholesterol-transport/steroidogenesis model by showing global Tspo knockout mice are viable with normal steroids, while revealing reduced microglial ATP\\u2014redirecting the field toward bioenergetics.\",\n      \"evidence\": \"Global Tspo knockout mouse with PET imaging, cholesterol/pregnenolone/protoporphyrin assays, and microglial ATP measurement\",\n      \"pmids\": [\"25406832\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Compensatory adaptation in knockout not fully resolved\", \"Mechanism linking TSPO to ATP not defined here\"]\n    },\n    {\n      \"year\": 2014,\n      \"claim\": \"Defined the ligand-dependent conformational behaviour of TSPO, showing a rigid five-helix bundle when PK11195-bound versus dynamic exchange and local unfolding when unbound.\",\n      \"evidence\": \"Solution-state NMR structure of mouse TSPO with PK11195 and conformational dynamics analysis\",\n      \"pmids\": [\"26394723\", \"26551694\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Functional consequence of conformational dynamics in vivo unclear\", \"Endogenous ligand state not captured\"]\n    },\n    {\n      \"year\": 2015,\n      \"claim\": \"Provided atomic-resolution architecture of TSPO, defining the dimer, an endogenous porphyrin-binding site, and the structural impact of the human Ala147Thr polymorphism on cholesterol binding.\",\n      \"evidence\": \"X-ray crystallography of Rhodobacter TSPO in lipidic cubic phase with mutagenesis mimicking the human polymorphism\",\n      \"pmids\": [\"25635101\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Bacterial ortholog; human-specific features inferred via mutagenesis\", \"Cholesterol-transport function not demonstrated structurally\"]\n    },\n    {\n      \"year\": 2016,\n      \"claim\": \"Established a direct metabolic function: TSPO loss shifts mitochondrial substrate use from glucose to fatty acids with elevated FAO and ROS, defining TSPO as a bioenergetic regulator.\",\n      \"evidence\": \"CRISPR/Cas9 knockout in MA-10 cells with Seahorse flux analysis, gene profiling, and corroboration in Tspo-/- mouse adrenal\",\n      \"pmids\": [\"26741196\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Molecular mechanism coupling TSPO to substrate choice unknown\", \"Direct lipid-handling activity not shown\"]\n    },\n    {\n      \"year\": 2017,\n      \"claim\": \"Gain-of-function showed de novo TSPO expression upregulates ETC genes, raises ATP, and increases proliferation/motility, reinforcing a bioenergetic and growth-promoting role.\",\n      \"evidence\": \"Stable TSPO transfection into TSPO-low Jurkat cells with RT-qPCR, patch-clamp, ATP and proliferation/motility assays, plus PK11195 inhibition\",\n      \"pmids\": [\"28103132\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Single cell system\", \"Mechanism connecting TSPO to ETC gene transcription unresolved\"]\n    },\n    {\n      \"year\": 2019,\n      \"claim\": \"Connected TSPO to organismal energy balance by showing tanycytic TSPO loss triggers AMPK-dependent lipophagy, reducing food intake and raising energy expenditure.\",\n      \"evidence\": \"Tanycyte-specific Rax-Cre knockout with ICV PK11195, metabolic cage studies, and lipophagy/AMPK pathway analysis\",\n      \"pmids\": [\"31469345\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct molecular target of TSPO in lipophagy not identified\", \"Single lab\"]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"Showed TSPO controls microglial activation through mitochondrial metabolism, with deficiency suppressing OXPHOS, glycolysis, membrane potential, and ATP.\",\n      \"evidence\": \"Knockout-derived primary microglia and siRNA knockdown with LPS/IL-4 activation and Seahorse metabolic analysis\",\n      \"pmids\": [\"32695005\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Mechanism coupling TSPO to metabolic flux unresolved\", \"Single lab\"]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"Identified neuronal activity as a driver of TSPO expression, refining interpretation of TSPO as a glial-activation imaging marker.\",\n      \"evidence\": \"Single-cell RNA-seq with DREADD chemogenetics, novel environment, and amphetamine stimulation plus confocal microscopy\",\n      \"pmids\": [\"32398717\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Functional consequence of neuronal TSPO induction unknown\", \"Single lab\"]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"Extended TSPO loss-of-function phenotypes to reproduction and lipid homeostasis, with delayed embryonic development and reduced testosterone alongside compensatory cholesterol-transport gene upregulation.\",\n      \"evidence\": \"Amhr2-Cre Tspo knockout with embryo morphology, testosterone ELISA, lipid analysis, and RNA-seq\",\n      \"pmids\": [\"32099945\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Testosterone reduction contrasts with normal steroids in other knockouts\", \"Compensatory mechanisms not mechanistically dissected\"]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"Placed TSPO upstream of NOX1-dependent neurotoxic ROS in retinal phagocytes, defining a controllable node in microglial reactivity and neovascular pathology.\",\n      \"evidence\": \"Cx3cr1-CreERT2 conditional knockout, XBD173 ligand treatment, and genetic epistasis with NADPH oxidase-deficient mice in a laser-induced CNV model\",\n      \"pmids\": [\"32483169\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Biochemical link between TSPO and NOX1 not resolved\", \"Generalizability beyond retina untested\"]\n    },\n    {\n      \"year\": 2021,\n      \"claim\": \"Demonstrated TSPO is required for microglial phagocytic clearance of amyloid-\\u03b2, with deficiency worsening plaque burden and inflammation in APP/PS1 mice.\",\n      \"evidence\": \"TSPO knockout in APP/PS1 background with primary microglial phagocytosis assays, cytokine ELISA, and plaque quantification\",\n      \"pmids\": [\"34340010\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Mechanistic link from TSPO metabolism to phagocytosis not defined\", \"Single lab\"]\n    },\n    {\n      \"year\": 2021,\n      \"claim\": \"Revealed a role in retinal lipid homeostasis, with TSPO deletion elevating cholesterol/lipids, perturbing efflux, and inducing inflammation.\",\n      \"evidence\": \"Tspo knockout mouse retina with histology, biochemical lipid assays, gene profiling, and cytokine measurement\",\n      \"pmids\": [\"34831289\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct lipid-transport activity not demonstrated\", \"Cell-type contribution within retina unresolved\"]\n    },\n    {\n      \"year\": 2022,\n      \"claim\": \"Showed diazepam-induced cognitive and spine deficits act through TSPO rather than GABAA receptors by enhancing microglial phagocytosis of synaptic material, reframing benzodiazepine neurotoxicity.\",\n      \"evidence\": \"TSPO-specific genetic manipulation, two-photon spine imaging, microglial phagocytosis assays, and PET in mice\",\n      \"pmids\": [\"35228700\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Signaling cascade from TSPO ligand binding to phagocytosis unresolved\", \"Endogenous ligand for this pathway unknown\"]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Defined a physical TSPO\\u2013p62/SQSTM1 interaction that blocks autophagy and activates Nrf2 antioxidant and PD-L1 immune-evasion programs in tumor cells.\",\n      \"evidence\": \"Co-immunoprecipitation with gain/loss-of-function, autophagy assays, and Nrf2/KEAP1/p62 pathway analysis in HCC models\",\n      \"pmids\": [\"36994647\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Co-IP without reciprocal structural validation of the interface\", \"Interaction generality beyond HCC untested\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"The molecular activity that couples TSPO's structural dynamics and ligand binding to its downstream control of mitochondrial substrate use, ROS, autophagy, and phagocytosis, and the identity of its physiological endogenous ligand, remain undefined.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No defined enzymatic or transport activity for TSPO\", \"Endogenous ligand mediating in vivo functions unidentified\", \"Mechanistic chain from TSPO to bioenergetic/phagocytic outputs not reconstituted\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0008289\", \"supporting_discovery_ids\": [0, 15, 13]},\n      {\"term_id\": \"GO:0098772\", \"supporting_discovery_ids\": [2, 7, 9]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005739\", \"supporting_discovery_ids\": [2, 6, 16]},\n      {\"term_id\": \"GO:0005886\", \"supporting_discovery_ids\": [6]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-1430728\", \"supporting_discovery_ids\": [2, 9, 13]},\n      {\"term_id\": \"R-HSA-168256\", \"supporting_discovery_ids\": [7, 8, 14]},\n      {\"term_id\": \"R-HSA-9612973\", \"supporting_discovery_ids\": [9, 11]}\n    ],\n    \"complexes\": [],\n    \"partners\": [\"VDAC\", \"p62/SQSTM1\", \"PAP7\"],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":7,"faith_total":7,"faith_pct":100.0}}