{"gene":"ELOVL3","run_date":"2026-06-09T23:54:43","timeline":{"discoveries":[{"year":2003,"finding":"ELOVL3 is a microsomal enzyme required for elongation of fatty acids beyond 20 carbons; disruption of the Elovl3 gene in mice causes near-complete absence of fatty acids >20 carbons in triglycerides (especially in the skin/hair), with accumulation of eicosenoic acid (20:1), establishing ELOVL3 as the elongase responsible for C20+ neutral lipid fatty acid synthesis in sebaceous glands and hair follicle epithelial cells.","method":"Elovl3 gene knockout by homologous recombination in mouse; fatty acid profiling of hair lipids and triglyceride fractions; histological analysis of pilosebaceous system; trans-epidermal water loss measurement","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 2 / Strong — clean genetic knockout with defined biochemical phenotype (fatty acid profiling), replicated across multiple tissue compartments, functional consequences measured by TEWL","pmids":["14581464"],"is_preprint":false},{"year":2005,"finding":"ELOVL3 is required for elongation of saturated fatty acyl-CoAs into very long chain fatty acids (C20:0, C22:0) in brown adipose tissue; Elovl3-ablated mice show decreased condensation activity of the elongation enzyme and reduced arachidic and behenic acid levels during cold stress, establishing ELOVL3 as a critical elongase for saturated VLCFA synthesis and triglyceride formation in BAT during early tissue recruitment.","method":"Elovl3 knockout mice; cold acclimation protocol; in vitro elongation condensation activity assay on BAT extracts; fatty acid composition analysis; body temperature monitoring; muscle shivering measurement","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 1–2 / Strong — in vitro enzymatic condensation assay combined with genetic knockout and lipid profiling, demonstrating direct catalytic function","pmids":["16326704"],"is_preprint":false},{"year":2005,"finding":"Elovl3 expression in brown adipocytes is transcriptionally controlled by PPARα (induced by PPARα ligand Wy-14643 in concert with norepinephrine and dexamethasone), while LXR/SREBP-1 activation represses Elovl3 expression and increases Elovl1; this differential regulation establishes ELOVL3 in a distinct transcriptional program linked to oxidative (non-lipogenic) metabolic states, functionally reflected in C22:0 esterified fatty acid levels.","method":"Primary brown adipocyte cultures; PPARα/LXRα ligand treatments; mRNA expression analysis; nuclear LXR and SREBP-1 abundance measurement; fatty acid composition analysis of esterified lipids","journal":"American journal of physiology. Endocrinology and metabolism","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — pharmacological ligand experiments in primary cells with lipid readout; single lab, two orthogonal approaches (gene expression + lipid analysis)","pmids":["15855229"],"is_preprint":false},{"year":2006,"finding":"Circadian expression of Elovl3 in mouse liver is perturbed in CLOCK-mutant mice and is activated by SREBP1 and repressed by RevErbα at the Elovl3 promoter; proteolytic activation of SREBP1 is itself circadian in the liver and responds to meal timing, placing ELOVL3 downstream of a clock–nutrition integration mechanism.","method":"CLOCK mutant mouse liver analysis; promoter reporter assays with SREBP1 and RevErbα; meal-restriction experiments with inverted feeding; hepatic dysfunction mouse model","journal":"Journal of lipid research","confidence":"Medium","confidence_rationale":"Tier 2–3 / Moderate — promoter reporter assay plus genetic mouse models, single lab, multiple complementary approaches","pmids":["17003504"],"is_preprint":false},{"year":2007,"finding":"Elovl3 expression in brown adipocytes is synergistically induced by norepinephrine and the PPARγ ligand rosiglitazone; this induction requires novel protein synthesis, is achieved through both increased transcription and increased mRNA stability, and rosiglitazone is orders of magnitude more potent than PPARα or PPARδ ligands, placing ELOVL3 downstream of PPARγ and sympathetic activation in brown adipocyte lipid accumulation.","method":"Primary brown adipocyte cultures; norepinephrine and rosiglitazone (PPARγ agonist) treatment; quantitative mRNA analysis; mRNA stability assay; protein synthesis inhibitor (cycloheximide) treatment; comparison with PPARα and PPARδ ligands","journal":"American journal of physiology. Endocrinology and metabolism","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — pharmacological dissection in primary cells with multiple ligand comparisons and mRNA stability experiments; single lab","pmids":["17726147"],"is_preprint":false},{"year":2008,"finding":"Hepatic Elovl3 expression follows a sexually dimorphic circadian rhythm controlled by glucocorticoids and androgens; dexamethasone (synthetic glucocorticoid) transcriptionally induces Elovl3 in mouse liver, and expression is elevated in ABCD2-ablated mice and suppressed in ABCD2-overexpressing mice, revealing cross-talk between VLCFA synthesis (ELOVL3) and peroxisomal VLCFA oxidation (ABCD2).","method":"Zeitgeber time-series mRNA analysis in male/female/immature mice; fasting/refeeding and restricted feeding experiments; dexamethasone injection; ABCD2 knockout and transgenic overexpression mouse models; castration experiments","journal":"Endocrinology","confidence":"Medium","confidence_rationale":"Tier 2–3 / Moderate — multiple genetic mouse models plus pharmacological manipulation; single lab; temporal expression profiling with functional genetic controls","pmids":["18292190"],"is_preprint":false},{"year":2010,"finding":"ELOVL3 synthesizes C20–C24 saturated and monounsaturated VLCFAs in liver, brown and white adipose tissue, and triglyceride-rich glands; ablation reduces hepatic de novo fatty acid synthesis, fatty acid uptake, triglyceride content, and VLDL-triglyceride secretion, and constrains adipose tissue expansion, demonstrating that ELOVL3-derived VLCFAs are required for hepatic triglyceride synthesis and adipose lipid storage.","method":"Global Elovl3 knockout mice; diet-induced obesity model; hepatic lipogenic gene expression analysis; in vivo de novo fatty acid synthesis measurement; VLDL-TG secretion assay; serum adiponectin and leptin measurement; adipose tissue histology","journal":"FASEB journal","confidence":"High","confidence_rationale":"Tier 2 / Strong — global KO with in vivo lipid synthesis measurements, lipoprotein secretion assays, and multiple tissue-level readouts; multiple orthogonal methods","pmids":["20605947"],"is_preprint":false},{"year":2012,"finding":"PPARγ directly binds three PPAR-responsive elements in the Elovl3 promoter to activate transcription during adipogenesis; C18:1 and C20:1 VLCFAs produced by ELOVL3 act as PPARγ agonists (coactivator recruitment in mammalian two-hybrid assay), creating a positive feedback loop (ELOVL3–VLCFA–PPARγ) that sustains adipogenic gene expression.","method":"3T3-L1 adipogenesis model; Elovl3 siRNA knockdown; promoter-reporter assays with PPRE mutations; chromatin immunoprecipitation (ChIP) for PPARγ at Elovl3 promoter; mammalian two-hybrid assay for C18:1 and C20:1 activation of PPARγ; PPARγ antagonist rescue experiment","journal":"American journal of physiology. Endocrinology and metabolism","confidence":"High","confidence_rationale":"Tier 1–2 / Moderate — ChIP, promoter-reporter with mutagenesis, mammalian two-hybrid, and siRNA rescue; multiple orthogonal methods in single lab","pmids":["22436697"],"is_preprint":false},{"year":2015,"finding":"Vitamin D receptor (VDR) directly occupies a negative-response element in the proximal Elovl3 promoter in a ligand-dependent manner, transcriptionally repressing Elovl3 expression specifically in subcutaneous white adipose tissue; VDR deletion leads to increased C18–C24 saturated and monounsaturated fatty acids in sc WAT, placing ELOVL3 as a direct VDR target responsible for tissue-specific fatty acid composition.","method":"VDR knockout (VDRKO) mice; fatty acid composition analysis of sc and visceral WAT depots; ChIP assay for VDR occupancy at Elovl3 promoter negative-response element; in vivo vitamin D treatment; tissue-specific gene expression analysis","journal":"Endocrinology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — ChIP for VDR at promoter plus in vivo genetic model and lipid profiling; single lab","pmids":["26488808"],"is_preprint":false},{"year":2019,"finding":"BRG1 (chromatin remodeling ATPase) is recruited by the nuclear receptor RORγ to the Elovl3 promoter to activate transcription in prostate cancer cells in response to androgen and TGF-β; BRG1 also interacts with histone acetyltransferase p300 at the Elovl3 promoter, and p300 inhibition or depletion attenuates Elovl3 trans-activation, linking ELOVL3 expression to BRG1–RORγ–p300 epigenetic co-activation.","method":"BRG1 overexpression and knockdown in prostate cancer cells; Elovl3 promoter ChIP assay for BRG1 and p300; Co-immunoprecipitation of BRG1 with RORγ; siRNA knockdown of p300; curcumin (p300 inhibitor) treatment; cell migration and invasion assays","journal":"Biochimica et biophysica acta. Gene regulatory mechanisms","confidence":"Medium","confidence_rationale":"Tier 2–3 / Moderate — reciprocal Co-IP plus ChIP and pharmacological inhibition; single lab, multiple complementary methods","pmids":["31154107"],"is_preprint":false},{"year":2019,"finding":"ELOVL3 is required for production of C21:0–C29:0 fatty acids (including odd-chain and branched chain species) in meibomian glands; ELOVL3 ablation causes selective depletion of cholesteryl esters, wax esters, and cholesteryl esters of O-acylated ω-hydroxy fatty acids in tarsal plates, demonstrating ELOVL3's essential catalytic role in meibogenesis.","method":"Elovl3 knockout mice vs. wild-type; chromatographic and mass spectrometric lipid profiling of tarsal plate lipids; slit lamp examination; histological analysis of ocular tissues","journal":"FASEB journal","confidence":"High","confidence_rationale":"Tier 1–2 / Strong — genetic KO with quantitative mass spectrometry lipid profiling identifying specific substrate/product chain lengths; multiple lipid classes analyzed","pmids":["31208226"],"is_preprint":false},{"year":2019,"finding":"Sustained rhythmic expression of hepatic Elovl3 requires coordination between the circadian clock (BMAL1) and androgen signaling; NR1D1 (RevErbα) binds the Elovl3 promoter in a circadian-dependent manner in vivo; castration abolishes Elovl3 levels in male liver but not circadian variation, while 5α-dihydrotestosterone induces Elovl3 in female livers and AML12 cells in a time- and androgen receptor-dependent manner.","method":"Bmal1 knockout mice; ChIP assay for NR1D1 binding at Elovl3 promoter across circadian time; castration experiments; 5α-dihydrotestosterone injection in female mice; flutamide (androgen receptor antagonist) treatment in AML12 cells; zeitgeber/circadian time series mRNA analysis","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 2 / Strong — ChIP demonstrating direct NR1D1 binding, genetic BMAL1 KO, castration/hormone replacement in vivo, and pharmacological AR blockade; multiple orthogonal approaches","pmids":["30862677"],"is_preprint":false},{"year":2021,"finding":"ELOVL3 ablation reduces meibum melting temperature by ~8°C and increases meibum fluidity, demonstrating that ELOVL3-derived VLCFAs determine the thermotropic/physical properties of meibum; transcriptomic analysis of meibomian glands reveals that ELOVL3 loss dysregulates lipid biosynthesis, inflammation, and stress response gene networks.","method":"Elovl3 knockout mice; heat-stage polarized light microscopy for meibum melting temperature; histological examination; MG transcriptome analysis (RNA-seq); slit lamp examination","journal":"FASEB journal","confidence":"Medium","confidence_rationale":"Tier 2–3 / Moderate — genetic KO with direct physical measurement of meibum melting properties and transcriptomics; single lab","pmids":["33455016"],"is_preprint":false},{"year":2023,"finding":"ZHX2 (zinc fingers and homeoboxes 2) transcription factor positively regulates Elovl3 expression in mouse liver; forced Elovl3 expression in human hepatoma cells reduces cell growth and causes cell cycle arrest in S-phase with reduced cyclin mRNA levels, demonstrating that ELOVL3-derived VLCFAs regulate hepatocyte proliferation and cell cycle progression.","method":"Mouse microarray and in vivo liver regeneration models; cell-based Elovl3 overexpression in hepatoma lines; cell growth assays; cell synchronization and cell cycle analysis; cyclin mRNA measurement; VLCFA profiling; Zhx2-null mouse livers","journal":"American journal of physiology. Gastrointestinal and liver physiology","confidence":"Medium","confidence_rationale":"Tier 2–3 / Moderate — forced expression with cell cycle analysis plus genetic mouse models and lipid profiling; single lab","pmids":["37847682"],"is_preprint":false},{"year":2023,"finding":"Hepatic-specific deletion of Elovl3 (via Cre/LoxP) does not alter body weight, liver mass, liver triglyceride content, lipid profiles, or hepatic lipogenic/oxidative gene expression under normal chow or high-fat diet, demonstrating that hepatic ELOVL3 alone is dispensable for liver lipid homeostasis (negative finding; the anti-obesity phenotype in global KO is attributable to extrahepatic ELOVL3 function).","method":"Liver-specific Elovl3 Cre/LoxP knockout mice; high-fat diet challenge; body weight and liver mass measurement; lipidomics; liver triglyceride assay; hepatic gene expression (qRT-PCR and Western blot); glucose tolerance test; ELOVL1 and ELOVL7 expression controls","journal":"Biochemical and biophysical research communications","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — rigorous conditional KO with lipidomics and comprehensive metabolic phenotyping; single lab but multiple orthogonal readouts clearly establishing negative result","pmids":["37030067"],"is_preprint":false},{"year":2024,"finding":"Testosterone/androgen receptor (AR) negatively regulates ELOVL3 transcription through an androgen response element (ARE) in the ELOVL3 promoter; AR overexpression suppresses ELOVL3 promoter activity, and ELOVL3 knockdown reduces lipid droplet accumulation and FASN expression while increasing ATGL mRNA in porcine preadipocytes.","method":"Porcine preadipocyte model with testosterone treatment; transcriptomic sequencing; dual-luciferase reporter assay with wild-type and ARE-mutant ELOVL3 promoter; AR overexpression; ELOVL3 siRNA knockdown; lipid droplet staining; FASN and ATGL mRNA analysis","journal":"Animals","confidence":"Medium","confidence_rationale":"Tier 2–3 / Moderate — promoter reporter with ARE mutation plus siRNA knockdown and AR overexpression; single lab, multiple complementary methods","pmids":["39123669"],"is_preprint":false},{"year":2025,"finding":"BAT-specific deletion of Elovl3 causes cold intolerance due to impaired BAT thermogenesis and defective mitochondrial cristae remodeling; lipidomics reveals that Elovl3 deficiency markedly reduces lysophosphatidylcholine, cardiolipin, and acylcarnitine levels in BAT, identifying ELOVL3-derived VLCFAs as required components of BAT phospholipid homeostasis that support UCP1 expression and mitochondrial remodeling during cold adaptation.","method":"BAT-specific Elovl3 Cre/LoxP knockout mice; cold exposure challenge; body temperature measurement; Ucp1 expression (qRT-PCR and Western blot); BAT histology; lipidomics analysis; mitochondrial ultrastructure (histological evaluation of cristae remodeling); muscle shivering assessment","journal":"Journal of lipid research","confidence":"High","confidence_rationale":"Tier 2 / Strong — tissue-specific conditional KO with cold phenotyping, lipidomics, UCP1 expression, and mitochondrial morphology; multiple orthogonal methods in single study","pmids":["41202879"],"is_preprint":false},{"year":2026,"finding":"USP25 deubiquitinase binds and stabilizes PARP1 through deubiquitination; PARP1 in turn promotes preadipocyte differentiation and maturation by regulating ELOVL3 expression, placing ELOVL3 downstream of a USP25–PARP1 axis in adipocyte differentiation.","method":"Usp25 knockout mice; 3T3-L1 adipocyte differentiation model; RNA sequencing; Co-immunoprecipitation of USP25 and PARP1; ubiquitination assay; PARP1 knockdown with Elovl3 expression readout; adipose tissue histology","journal":"Journal of lipid research","confidence":"Medium","confidence_rationale":"Tier 2–3 / Moderate — Co-IP for USP25–PARP1 interaction and ubiquitination assay with genetic KO; ELOVL3 placement is downstream inference from PARP1 manipulation; single lab","pmids":["41692245"],"is_preprint":false}],"current_model":"ELOVL3 is a microsomal fatty acid elongase that catalyzes condensation reactions to extend saturated and monounsaturated fatty acyl-CoAs in the C18–C24 range (producing C20–C24 VLCFAs), functioning critically in sebaceous/meibomian glands, brown and white adipose tissue, and liver; its substrates and products govern skin barrier lipid composition, meibum physical properties, BAT phospholipid homeostasis and mitochondrial cristae remodeling for thermogenesis, and hepatic/adipose triglyceride synthesis, while its transcription is controlled by a network of PPARγ/PPARα, RORγ–BRG1–p300, NR1D1/BMAL1 circadian machinery, androgen/glucocorticoid signaling, SREBP1, VDR, and ZHX2, and ELOVL3-derived C18:1/C20:1 VLCFAs feed back as PPARγ agonists to sustain adipogenesis."},"narrative":{"mechanistic_narrative":"ELOVL3 is a microsomal fatty acid elongase that catalyzes the condensation step extending saturated and monounsaturated fatty acyl-CoAs into very long chain fatty acids (C20–C24+), governing neutral lipid composition across sebaceous glands, brown and white adipose tissue, liver, and meibomian glands [PMID:14581464, PMID:16326704, PMID:20605947]. Genetic ablation eliminates fatty acids beyond C20 in skin/hair triglycerides and abolishes cold-induced condensation activity for C20:0/C22:0 synthesis in brown adipose tissue, establishing its direct catalytic role [PMID:14581464, PMID:16326704]. The VLCFAs it produces are functionally indispensable: in meibomian glands they generate the C21–C29 species (including odd- and branched-chain) of cholesteryl and wax esters that set meibum melting temperature and fluidity [PMID:31208226, PMID:33455016], and in brown adipose tissue they sustain lysophosphatidylcholine, cardiolipin, and acylcarnitine pools required for UCP1 expression, mitochondrial cristae remodeling, and cold-adaptive thermogenesis [PMID:41202879]. ELOVL3-derived VLCFAs also support hepatic triglyceride synthesis, VLDL-TG secretion, and adipose lipid storage, with the systemic anti-obesity phenotype of global knockouts traced to extrahepatic ELOVL3, since hepatocyte-specific deletion leaves liver lipid homeostasis intact [PMID:20605947, PMID:37030067]. Transcription of ELOVL3 is integrated by a dense regulatory network: it is induced by PPARγ acting through promoter PPREs during adipogenesis—with ELOVL3-derived C18:1/C20:1 feeding back as PPARγ agonists in a positive loop [PMID:22436697]—and by PPARα with sympathetic input in brown adipocytes [PMID:15855229, PMID:17726147], while being controlled circadianly by SREBP1, NR1D1/RevErbα, and BMAL1 in coordination with androgen signaling [PMID:17003504, PMID:30862677], and repressed by VDR and androgen receptor through dedicated promoter response elements [PMID:26488808, PMID:39123669]; additional inputs include RORγ–BRG1–p300 epigenetic co-activation and the transcription factor ZHX2, the latter linking ELOVL3 to control of hepatocyte cell-cycle progression [PMID:31154107, PMID:37847682].","teleology":[{"year":2003,"claim":"Established that ELOVL3 is the elongase responsible for synthesizing C20+ fatty acids in skin/hair neutral lipids, defining its core enzymatic identity.","evidence":"Elovl3 knockout mice with hair/triglyceride fatty acid profiling and trans-epidermal water loss measurement","pmids":["14581464"],"confidence":"High","gaps":["Did not establish substrate chain-length specificity by in vitro assay","Did not address roles outside the pilosebaceous system"]},{"year":2005,"claim":"Demonstrated direct catalytic condensation activity of ELOVL3 on saturated acyl-CoAs in brown adipose tissue and linked it to cold-stress thermogenesis, extending its function beyond skin.","evidence":"In vitro elongation condensation assay on BAT extracts from knockout mice plus cold acclimation phenotyping","pmids":["16326704"],"confidence":"High","gaps":["Did not resolve the molecular basis of the thermogenic deficit","Tissue-autonomy of the BAT requirement not established"]},{"year":2005,"claim":"Placed ELOVL3 in a PPARα-driven, oxidative transcriptional program distinct from LXR/SREBP-1-driven lipogenesis in brown adipocytes.","evidence":"Pharmacological ligand treatments in primary brown adipocytes with mRNA and esterified lipid analysis","pmids":["15855229"],"confidence":"Medium","gaps":["No direct promoter occupancy demonstrated","Single lab pharmacological inference"]},{"year":2006,"claim":"Connected ELOVL3 transcription to circadian and nutritional control via SREBP1 activation and RevErbα repression at its promoter.","evidence":"CLOCK-mutant mouse liver analysis with SREBP1/RevErbα promoter reporter assays and meal-restriction experiments","pmids":["17003504"],"confidence":"Medium","gaps":["In vivo direct binding not shown in this study","Functional lipid consequence of clock disruption not measured"]},{"year":2007,"claim":"Showed ELOVL3 induction integrates sympathetic and PPARγ signals through both transcription and mRNA stabilization in brown adipocytes.","evidence":"Norepinephrine/rosiglitazone treatment of primary brown adipocytes with mRNA stability and cycloheximide experiments","pmids":["17726147"],"confidence":"Medium","gaps":["Did not identify the labile protein required for induction","mRNA stabilization mechanism unresolved"]},{"year":2008,"claim":"Revealed sexually dimorphic, hormonally controlled circadian regulation of hepatic ELOVL3 and cross-talk with peroxisomal VLCFA oxidation via ABCD2.","evidence":"Time-series mRNA profiling, dexamethasone injection, castration, and ABCD2 knockout/transgenic mouse models","pmids":["18292190"],"confidence":"Medium","gaps":["Direct promoter targets of glucocorticoid/androgen not mapped here","Mechanism of ELOVL3–ABCD2 cross-talk not defined"]},{"year":2010,"claim":"Defined ELOVL3 as a determinant of systemic lipid handling—hepatic de novo synthesis, VLDL-TG secretion, and adipose expansion—broadening its role to whole-body energy storage.","evidence":"Global knockout mice under diet-induced obesity with in vivo fatty acid synthesis, VLDL-TG secretion assays, and tissue histology","pmids":["20605947"],"confidence":"High","gaps":["Did not resolve which tissue drives the systemic phenotype","Mechanism linking VLCFA to TG synthesis not detailed"]},{"year":2012,"claim":"Established a feed-forward loop in which PPARγ directly activates ELOVL3 and ELOVL3-derived C18:1/C20:1 VLCFAs act as PPARγ agonists to sustain adipogenesis.","evidence":"ChIP, PPRE-mutant promoter reporters, mammalian two-hybrid, and siRNA rescue in 3T3-L1 cells","pmids":["22436697"],"confidence":"High","gaps":["Endogenous VLCFA-PPARγ binding affinity not quantified","Loop dynamics in vivo not established"]},{"year":2015,"claim":"Identified ELOVL3 as a direct VDR repression target controlling fatty acid composition specifically in subcutaneous white adipose tissue.","evidence":"VDR knockout mice with ChIP at a promoter negative-response element and depot-specific lipid profiling","pmids":["26488808"],"confidence":"Medium","gaps":["Physiological trigger for VDR-mediated repression unclear","Depot specificity mechanism unexplained"]},{"year":2019,"claim":"Demonstrated epigenetic co-activation of ELOVL3 by a RORγ–BRG1–p300 complex in prostate cancer cells responding to androgen and TGF-β.","evidence":"BRG1/p300 ChIP, reciprocal Co-IP with RORγ, p300 inhibition, and migration/invasion assays in prostate cancer cells","pmids":["31154107"],"confidence":"Medium","gaps":["Functional contribution of ELOVL3 lipids to cancer phenotype not established","Single lab; cancer-cell context only"]},{"year":2019,"claim":"Defined ELOVL3's essential catalytic role in meibogenesis, producing the long and odd/branched-chain fatty acids of meibum lipid esters.","evidence":"Knockout mice with mass spectrometric lipidomics of tarsal plate lipids","pmids":["31208226"],"confidence":"High","gaps":["Functional/optical consequence for tear film not yet measured here","Substrate preference among classes not resolved"]},{"year":2019,"claim":"Showed sustained rhythmic hepatic ELOVL3 expression requires coordinated BMAL1 circadian and androgen-receptor signaling, with direct NR1D1 promoter binding.","evidence":"Bmal1 knockout, circadian NR1D1 ChIP, castration/DHT replacement in vivo, and flutamide treatment in AML12 cells","pmids":["30862677"],"confidence":"High","gaps":["Integration of androgen and clock inputs at promoter not fully mechanistic","Downstream lipid consequence of rhythm loss unaddressed"]},{"year":2021,"claim":"Connected ELOVL3-derived VLCFAs to the physical properties of meibum, showing loss lowers melting temperature and dysregulates gland gene networks.","evidence":"Knockout mice with heat-stage polarized light microscopy of meibum melting and meibomian gland RNA-seq","pmids":["33455016"],"confidence":"Medium","gaps":["Causal link between specific lipid species and melting behavior not isolated","In vivo tear-film clinical consequences not measured"]},{"year":2023,"claim":"Identified ZHX2 as a positive transcriptional regulator and linked ELOVL3-derived VLCFAs to control of hepatocyte cell-cycle progression.","evidence":"Zhx2-null mouse livers, liver regeneration models, and hepatoma overexpression with cell cycle and cyclin analysis","pmids":["37847682"],"confidence":"Medium","gaps":["Mechanism linking VLCFA to S-phase arrest unresolved","ZHX2 promoter binding not directly demonstrated"]},{"year":2023,"claim":"Showed hepatocyte-autonomous ELOVL3 is dispensable for liver lipid homeostasis, attributing the global-KO anti-obesity phenotype to extrahepatic ELOVL3.","evidence":"Liver-specific Cre/LoxP knockout with high-fat challenge, lipidomics, and comprehensive metabolic phenotyping","pmids":["37030067"],"confidence":"Medium","gaps":["Did not identify which extrahepatic tissue drives the systemic phenotype","Possible compensation by other elongases not fully excluded"]},{"year":2024,"claim":"Demonstrated direct androgen-receptor repression of ELOVL3 through a promoter ARE and its requirement for preadipocyte lipid droplet accumulation.","evidence":"ARE-mutant dual-luciferase reporters, AR overexpression, and siRNA knockdown with lipid droplet staining in porcine preadipocytes","pmids":["39123669"],"confidence":"Medium","gaps":["Conservation of ARE regulation across species not established","Mechanism linking ELOVL3 to FASN/ATGL changes unclear"]},{"year":2025,"claim":"Established BAT-autonomous ELOVL3 as essential for cold thermogenesis via maintenance of phospholipid pools supporting UCP1 and mitochondrial cristae remodeling.","evidence":"BAT-specific Cre/LoxP knockout with cold challenge, lipidomics, UCP1 expression, and mitochondrial ultrastructure","pmids":["41202879"],"confidence":"High","gaps":["Direct biochemical link between specific VLCFA species and cristae architecture not isolated","Cardiolipin remodeling mechanism not defined"]},{"year":2026,"claim":"Placed ELOVL3 downstream of a USP25–PARP1 axis driving preadipocyte differentiation, adding a deubiquitination-dependent regulatory layer.","evidence":"Usp25 knockout mice, USP25–PARP1 Co-IP and ubiquitination assays, and PARP1 knockdown with Elovl3 readout in 3T3-L1 cells","pmids":["41692245"],"confidence":"Medium","gaps":["ELOVL3 placement is inferred downstream of PARP1, not directly mechanistic","Whether PARP1 acts on the ELOVL3 promoter is not shown"]},{"year":null,"claim":"The structural basis of ELOVL3 substrate selectivity and the precise mechanism by which its VLCFA products shape membrane phospholipid architecture and signaling remain unresolved.","evidence":"No structural or reconstituted enzymatic studies present in the corpus","pmids":[],"confidence":"Low","gaps":["No structural model of the enzyme","Substrate-specificity determinants not mapped","Mechanism by which VLCFAs alter cristae and PPARγ activity not biochemically defined"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0016740","term_label":"transferase activity","supporting_discovery_ids":[0,1,6,10,16]}],"localization":[{"term_id":"GO:0005783","term_label":"endoplasmic reticulum","supporting_discovery_ids":[0]}],"pathway":[{"term_id":"R-HSA-1430728","term_label":"Metabolism","supporting_discovery_ids":[0,1,6,16]},{"term_id":"R-HSA-74160","term_label":"Gene expression (Transcription)","supporting_discovery_ids":[7,8,11,15]}],"complexes":[],"partners":[],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"Q9HB03","full_name":"Very long chain fatty acid elongase 3","aliases":["3-keto acyl-CoA synthase ELOVL3","Cold-inducible glycoprotein of 30 kDa","ELOVL fatty acid elongase 3","ELOVL FA elongase 3","Elongation of very long chain fatty acids protein 3","Very long chain 3-ketoacyl-CoA synthase 3","Very long chain 3-oxoacyl-CoA synthase 3"],"length_aa":270,"mass_kda":31.5,"function":"Catalyzes the first and rate-limiting reaction of the four reactions that constitute the long-chain fatty acids elongation cycle. This endoplasmic reticulum-bound enzymatic process allows the addition of 2 carbons to the chain of long- and very long-chain fatty acids (VLCFAs) per cycle. Condensing enzyme that exhibits activity toward saturated and unsaturated acyl-CoA substrates with higher activity toward C18 acyl-CoAs, especially C18:0 acyl-CoAs. May participate in the production of saturated and monounsaturated VLCFAs of different chain lengths that are involved in multiple biological processes as precursors of membrane lipids and lipid mediators","subcellular_location":"Endoplasmic reticulum membrane","url":"https://www.uniprot.org/uniprotkb/Q9HB03/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/ELOVL3","classification":"Not Classified","n_dependent_lines":4,"n_total_lines":1208,"dependency_fraction":0.0033112582781456954},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[],"url":"https://opencell.sf.czbiohub.org/search/ELOVL3","total_profiled":1310},"omim":[{"mim_id":"611815","title":"ELONGATION OF VERY LONG CHAIN FATTY ACIDS-LIKE 3; ELOVL3","url":"https://www.omim.org/entry/611815"},{"mim_id":"611814","title":"ELONGATION OF VERY LONG CHAIN FATTY ACIDS-LIKE 2; ELOVL2","url":"https://www.omim.org/entry/611814"},{"mim_id":"611813","title":"ELONGATION OF VERY LONG CHAIN FATTY ACIDS-LIKE 1; ELOVL1","url":"https://www.omim.org/entry/611813"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Approved","locations":[{"location":"Vesicles","reliability":"Approved"},{"location":"Cytosol","reliability":"Approved"}],"tissue_specificity":"Tissue enriched","tissue_distribution":"Detected in some","driving_tissues":[{"tissue":"skin 1","ntpm":28.1}],"url":"https://www.proteinatlas.org/search/ELOVL3"},"hgnc":{"alias_symbol":["CIG-30"],"prev_symbol":[]},"alphafold":{"accession":"Q9HB03","domains":[{"cath_id":"-","chopping":"65-260","consensus_level":"high","plddt":93.3465,"start":65,"end":260}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q9HB03","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q9HB03-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q9HB03-F1-predicted_aligned_error_v6.png","plddt_mean":90.56},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=ELOVL3","jax_strain_url":"https://www.jax.org/strain/search?query=ELOVL3"},"sequence":{"accession":"Q9HB03","fasta_url":"https://rest.uniprot.org/uniprotkb/Q9HB03.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q9HB03/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q9HB03"}},"corpus_meta":[{"pmid":"14581464","id":"PMC_14581464","title":"Role for ELOVL3 and fatty acid chain length in development of hair and skin function.","date":"2003","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/14581464","citation_count":162,"is_preprint":false},{"pmid":"16326704","id":"PMC_16326704","title":"ELOVL3 is an important component for early onset of lipid recruitment in brown adipose tissue.","date":"2005","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/16326704","citation_count":125,"is_preprint":false},{"pmid":"20605947","id":"PMC_20605947","title":"Ablation of the very-long-chain fatty acid elongase ELOVL3 in mice leads to constrained lipid storage and resistance to diet-induced obesity.","date":"2010","source":"FASEB journal : official publication of the Federation of American Societies for Experimental Biology","url":"https://pubmed.ncbi.nlm.nih.gov/20605947","citation_count":95,"is_preprint":false},{"pmid":"31154107","id":"PMC_31154107","title":"The chromatin remodeling protein BRG1 links ELOVL3 trans-activation to prostate cancer metastasis.","date":"2019","source":"Biochimica et biophysica acta. Gene regulatory mechanisms","url":"https://pubmed.ncbi.nlm.nih.gov/31154107","citation_count":50,"is_preprint":false},{"pmid":"15855229","id":"PMC_15855229","title":"Differential regulation of fatty acid elongation enzymes in brown adipocytes implies a unique role for Elovl3 during increased fatty acid oxidation.","date":"2005","source":"American journal of physiology. Endocrinology and metabolism","url":"https://pubmed.ncbi.nlm.nih.gov/15855229","citation_count":50,"is_preprint":false},{"pmid":"22436697","id":"PMC_22436697","title":"Very long-chain-fatty acids enhance adipogenesis through coregulation of Elovl3 and PPARγ in 3T3-L1 cells.","date":"2012","source":"American journal of physiology. Endocrinology and metabolism","url":"https://pubmed.ncbi.nlm.nih.gov/22436697","citation_count":49,"is_preprint":false},{"pmid":"18292190","id":"PMC_18292190","title":"Steroid hormones control circadian Elovl3 expression in mouse liver.","date":"2008","source":"Endocrinology","url":"https://pubmed.ncbi.nlm.nih.gov/18292190","citation_count":43,"is_preprint":false},{"pmid":"17003504","id":"PMC_17003504","title":"Elovl3: a model gene to dissect homeostatic links between the circadian clock and nutritional status.","date":"2006","source":"Journal of lipid research","url":"https://pubmed.ncbi.nlm.nih.gov/17003504","citation_count":41,"is_preprint":false},{"pmid":"31208226","id":"PMC_31208226","title":"On the pivotal role of Elovl3/ELOVL3 in meibogenesis and ocular physiology of mice.","date":"2019","source":"FASEB journal : official publication of the Federation of American Societies for Experimental Biology","url":"https://pubmed.ncbi.nlm.nih.gov/31208226","citation_count":38,"is_preprint":false},{"pmid":"30862677","id":"PMC_30862677","title":"Coordination between the circadian clock and androgen signaling is required to sustain rhythmic expression of Elovl3 in mouse liver.","date":"2019","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/30862677","citation_count":30,"is_preprint":false},{"pmid":"26488808","id":"PMC_26488808","title":"Vitamin D Regulates Fatty Acid Composition in Subcutaneous Adipose Tissue Through Elovl3.","date":"2015","source":"Endocrinology","url":"https://pubmed.ncbi.nlm.nih.gov/26488808","citation_count":29,"is_preprint":false},{"pmid":"17726147","id":"PMC_17726147","title":"Norepinephrine and rosiglitazone synergistically induce Elovl3 expression in brown adipocytes.","date":"2007","source":"American journal of physiology. Endocrinology and metabolism","url":"https://pubmed.ncbi.nlm.nih.gov/17726147","citation_count":26,"is_preprint":false},{"pmid":"29464364","id":"PMC_29464364","title":"Fatty acids promote bovine skeletal muscle satellite cell differentiation by regulating ELOVL3 expression.","date":"2018","source":"Cell and tissue research","url":"https://pubmed.ncbi.nlm.nih.gov/29464364","citation_count":23,"is_preprint":false},{"pmid":"37030067","id":"PMC_37030067","title":"Hepatic ELOVL3 is dispensable for lipid metabolism in mice.","date":"2023","source":"Biochemical and biophysical research communications","url":"https://pubmed.ncbi.nlm.nih.gov/37030067","citation_count":10,"is_preprint":false},{"pmid":"33455016","id":"PMC_33455016","title":"Physiological effects of inactivation and the roles of Elovl3/ELOVL3 in maintaining ocular homeostasis.","date":"2021","source":"FASEB journal : official publication of the Federation of American Societies for Experimental Biology","url":"https://pubmed.ncbi.nlm.nih.gov/33455016","citation_count":9,"is_preprint":false},{"pmid":"39123669","id":"PMC_39123669","title":"Testosterone Inhibits Lipid Accumulation in Porcine Preadipocytes by Regulating ELOVL3.","date":"2024","source":"Animals : an open access journal from MDPI","url":"https://pubmed.ncbi.nlm.nih.gov/39123669","citation_count":5,"is_preprint":false},{"pmid":"28780350","id":"PMC_28780350","title":"Effect of ELOVL3 expression on bovine skeletal muscle-derived satellite cell differentiation.","date":"2017","source":"Biochemical and biophysical research communications","url":"https://pubmed.ncbi.nlm.nih.gov/28780350","citation_count":1,"is_preprint":false},{"pmid":"41202879","id":"PMC_41202879","title":"ELOVL3 regulates phospholipid homeostasis and thermogenesis in brown adipose tissue.","date":"2025","source":"Journal of lipid research","url":"https://pubmed.ncbi.nlm.nih.gov/41202879","citation_count":1,"is_preprint":false},{"pmid":"37847682","id":"PMC_37847682","title":"Elongation of very long chain fatty acids-3 (Elovl3) is activated by ZHX2 and is a regulator of cell cycle progression.","date":"2023","source":"American journal of physiology. Gastrointestinal and liver physiology","url":"https://pubmed.ncbi.nlm.nih.gov/37847682","citation_count":1,"is_preprint":false},{"pmid":"39674643","id":"PMC_39674643","title":"Correlation and regression analysis of FA2H and ELOVL3 functional genes for cashmere fineness with production performance in Liaoning cashmere goat.","date":"2024","source":"Journal, genetic engineering & biotechnology","url":"https://pubmed.ncbi.nlm.nih.gov/39674643","citation_count":1,"is_preprint":false},{"pmid":"41692245","id":"PMC_41692245","title":"USP25 deficiency suppresses diet-induced obesity via ubiquitination and degradation of PARP1 and Elovl3 downregulation.","date":"2026","source":"Journal of lipid research","url":"https://pubmed.ncbi.nlm.nih.gov/41692245","citation_count":0,"is_preprint":false},{"pmid":"42153054","id":"PMC_42153054","title":"Impact of Elovl3 Suppression on Sleep Deprivation-Induced Hepatic Steatosis and Glucose Intolerance in Mice.","date":"2026","source":"Cureus","url":"https://pubmed.ncbi.nlm.nih.gov/42153054","citation_count":0,"is_preprint":false},{"pmid":null,"id":"bio_10.1101_2025.08.25.672195","title":"Lipid composition determines thermotropic properties of meibum of animals and humans with Meibomian gland disorders","date":"2025-08-29","source":"bioRxiv","url":"https://doi.org/10.1101/2025.08.25.672195","citation_count":0,"is_preprint":true},{"pmid":null,"id":"bio_10.1101_2025.03.13.643011","title":"Spatial Transcriptomics and Single-Nucleus RNA Sequencing Reveal rAAV2- and rAAV9-Specific Transduction Signatures in the Mouse Liver","date":"2025-03-15","source":"bioRxiv","url":"https://doi.org/10.1101/2025.03.13.643011","citation_count":0,"is_preprint":true}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":14361,"output_tokens":5569,"usd":0.063309,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":14332,"output_tokens":5219,"usd":0.101068,"stage2_stop_reason":"end_turn"},"total_usd":0.164377,"stage1_batch_id":"msgbatch_01AsR7g8dGTEiEw9U83bJeWn","stage2_batch_id":"msgbatch_01YV5ZyxtFNUZEjxRcpd9jzb","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2003,\n      \"finding\": \"ELOVL3 is a microsomal enzyme required for elongation of fatty acids beyond 20 carbons; disruption of the Elovl3 gene in mice causes near-complete absence of fatty acids >20 carbons in triglycerides (especially in the skin/hair), with accumulation of eicosenoic acid (20:1), establishing ELOVL3 as the elongase responsible for C20+ neutral lipid fatty acid synthesis in sebaceous glands and hair follicle epithelial cells.\",\n      \"method\": \"Elovl3 gene knockout by homologous recombination in mouse; fatty acid profiling of hair lipids and triglyceride fractions; histological analysis of pilosebaceous system; trans-epidermal water loss measurement\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — clean genetic knockout with defined biochemical phenotype (fatty acid profiling), replicated across multiple tissue compartments, functional consequences measured by TEWL\",\n      \"pmids\": [\"14581464\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2005,\n      \"finding\": \"ELOVL3 is required for elongation of saturated fatty acyl-CoAs into very long chain fatty acids (C20:0, C22:0) in brown adipose tissue; Elovl3-ablated mice show decreased condensation activity of the elongation enzyme and reduced arachidic and behenic acid levels during cold stress, establishing ELOVL3 as a critical elongase for saturated VLCFA synthesis and triglyceride formation in BAT during early tissue recruitment.\",\n      \"method\": \"Elovl3 knockout mice; cold acclimation protocol; in vitro elongation condensation activity assay on BAT extracts; fatty acid composition analysis; body temperature monitoring; muscle shivering measurement\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 / Strong — in vitro enzymatic condensation assay combined with genetic knockout and lipid profiling, demonstrating direct catalytic function\",\n      \"pmids\": [\"16326704\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2005,\n      \"finding\": \"Elovl3 expression in brown adipocytes is transcriptionally controlled by PPARα (induced by PPARα ligand Wy-14643 in concert with norepinephrine and dexamethasone), while LXR/SREBP-1 activation represses Elovl3 expression and increases Elovl1; this differential regulation establishes ELOVL3 in a distinct transcriptional program linked to oxidative (non-lipogenic) metabolic states, functionally reflected in C22:0 esterified fatty acid levels.\",\n      \"method\": \"Primary brown adipocyte cultures; PPARα/LXRα ligand treatments; mRNA expression analysis; nuclear LXR and SREBP-1 abundance measurement; fatty acid composition analysis of esterified lipids\",\n      \"journal\": \"American journal of physiology. Endocrinology and metabolism\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — pharmacological ligand experiments in primary cells with lipid readout; single lab, two orthogonal approaches (gene expression + lipid analysis)\",\n      \"pmids\": [\"15855229\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2006,\n      \"finding\": \"Circadian expression of Elovl3 in mouse liver is perturbed in CLOCK-mutant mice and is activated by SREBP1 and repressed by RevErbα at the Elovl3 promoter; proteolytic activation of SREBP1 is itself circadian in the liver and responds to meal timing, placing ELOVL3 downstream of a clock–nutrition integration mechanism.\",\n      \"method\": \"CLOCK mutant mouse liver analysis; promoter reporter assays with SREBP1 and RevErbα; meal-restriction experiments with inverted feeding; hepatic dysfunction mouse model\",\n      \"journal\": \"Journal of lipid research\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2–3 / Moderate — promoter reporter assay plus genetic mouse models, single lab, multiple complementary approaches\",\n      \"pmids\": [\"17003504\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2007,\n      \"finding\": \"Elovl3 expression in brown adipocytes is synergistically induced by norepinephrine and the PPARγ ligand rosiglitazone; this induction requires novel protein synthesis, is achieved through both increased transcription and increased mRNA stability, and rosiglitazone is orders of magnitude more potent than PPARα or PPARδ ligands, placing ELOVL3 downstream of PPARγ and sympathetic activation in brown adipocyte lipid accumulation.\",\n      \"method\": \"Primary brown adipocyte cultures; norepinephrine and rosiglitazone (PPARγ agonist) treatment; quantitative mRNA analysis; mRNA stability assay; protein synthesis inhibitor (cycloheximide) treatment; comparison with PPARα and PPARδ ligands\",\n      \"journal\": \"American journal of physiology. Endocrinology and metabolism\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — pharmacological dissection in primary cells with multiple ligand comparisons and mRNA stability experiments; single lab\",\n      \"pmids\": [\"17726147\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2008,\n      \"finding\": \"Hepatic Elovl3 expression follows a sexually dimorphic circadian rhythm controlled by glucocorticoids and androgens; dexamethasone (synthetic glucocorticoid) transcriptionally induces Elovl3 in mouse liver, and expression is elevated in ABCD2-ablated mice and suppressed in ABCD2-overexpressing mice, revealing cross-talk between VLCFA synthesis (ELOVL3) and peroxisomal VLCFA oxidation (ABCD2).\",\n      \"method\": \"Zeitgeber time-series mRNA analysis in male/female/immature mice; fasting/refeeding and restricted feeding experiments; dexamethasone injection; ABCD2 knockout and transgenic overexpression mouse models; castration experiments\",\n      \"journal\": \"Endocrinology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2–3 / Moderate — multiple genetic mouse models plus pharmacological manipulation; single lab; temporal expression profiling with functional genetic controls\",\n      \"pmids\": [\"18292190\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"ELOVL3 synthesizes C20–C24 saturated and monounsaturated VLCFAs in liver, brown and white adipose tissue, and triglyceride-rich glands; ablation reduces hepatic de novo fatty acid synthesis, fatty acid uptake, triglyceride content, and VLDL-triglyceride secretion, and constrains adipose tissue expansion, demonstrating that ELOVL3-derived VLCFAs are required for hepatic triglyceride synthesis and adipose lipid storage.\",\n      \"method\": \"Global Elovl3 knockout mice; diet-induced obesity model; hepatic lipogenic gene expression analysis; in vivo de novo fatty acid synthesis measurement; VLDL-TG secretion assay; serum adiponectin and leptin measurement; adipose tissue histology\",\n      \"journal\": \"FASEB journal\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — global KO with in vivo lipid synthesis measurements, lipoprotein secretion assays, and multiple tissue-level readouts; multiple orthogonal methods\",\n      \"pmids\": [\"20605947\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"PPARγ directly binds three PPAR-responsive elements in the Elovl3 promoter to activate transcription during adipogenesis; C18:1 and C20:1 VLCFAs produced by ELOVL3 act as PPARγ agonists (coactivator recruitment in mammalian two-hybrid assay), creating a positive feedback loop (ELOVL3–VLCFA–PPARγ) that sustains adipogenic gene expression.\",\n      \"method\": \"3T3-L1 adipogenesis model; Elovl3 siRNA knockdown; promoter-reporter assays with PPRE mutations; chromatin immunoprecipitation (ChIP) for PPARγ at Elovl3 promoter; mammalian two-hybrid assay for C18:1 and C20:1 activation of PPARγ; PPARγ antagonist rescue experiment\",\n      \"journal\": \"American journal of physiology. Endocrinology and metabolism\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 / Moderate — ChIP, promoter-reporter with mutagenesis, mammalian two-hybrid, and siRNA rescue; multiple orthogonal methods in single lab\",\n      \"pmids\": [\"22436697\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"Vitamin D receptor (VDR) directly occupies a negative-response element in the proximal Elovl3 promoter in a ligand-dependent manner, transcriptionally repressing Elovl3 expression specifically in subcutaneous white adipose tissue; VDR deletion leads to increased C18–C24 saturated and monounsaturated fatty acids in sc WAT, placing ELOVL3 as a direct VDR target responsible for tissue-specific fatty acid composition.\",\n      \"method\": \"VDR knockout (VDRKO) mice; fatty acid composition analysis of sc and visceral WAT depots; ChIP assay for VDR occupancy at Elovl3 promoter negative-response element; in vivo vitamin D treatment; tissue-specific gene expression analysis\",\n      \"journal\": \"Endocrinology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — ChIP for VDR at promoter plus in vivo genetic model and lipid profiling; single lab\",\n      \"pmids\": [\"26488808\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"BRG1 (chromatin remodeling ATPase) is recruited by the nuclear receptor RORγ to the Elovl3 promoter to activate transcription in prostate cancer cells in response to androgen and TGF-β; BRG1 also interacts with histone acetyltransferase p300 at the Elovl3 promoter, and p300 inhibition or depletion attenuates Elovl3 trans-activation, linking ELOVL3 expression to BRG1–RORγ–p300 epigenetic co-activation.\",\n      \"method\": \"BRG1 overexpression and knockdown in prostate cancer cells; Elovl3 promoter ChIP assay for BRG1 and p300; Co-immunoprecipitation of BRG1 with RORγ; siRNA knockdown of p300; curcumin (p300 inhibitor) treatment; cell migration and invasion assays\",\n      \"journal\": \"Biochimica et biophysica acta. Gene regulatory mechanisms\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2–3 / Moderate — reciprocal Co-IP plus ChIP and pharmacological inhibition; single lab, multiple complementary methods\",\n      \"pmids\": [\"31154107\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"ELOVL3 is required for production of C21:0–C29:0 fatty acids (including odd-chain and branched chain species) in meibomian glands; ELOVL3 ablation causes selective depletion of cholesteryl esters, wax esters, and cholesteryl esters of O-acylated ω-hydroxy fatty acids in tarsal plates, demonstrating ELOVL3's essential catalytic role in meibogenesis.\",\n      \"method\": \"Elovl3 knockout mice vs. wild-type; chromatographic and mass spectrometric lipid profiling of tarsal plate lipids; slit lamp examination; histological analysis of ocular tissues\",\n      \"journal\": \"FASEB journal\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 / Strong — genetic KO with quantitative mass spectrometry lipid profiling identifying specific substrate/product chain lengths; multiple lipid classes analyzed\",\n      \"pmids\": [\"31208226\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"Sustained rhythmic expression of hepatic Elovl3 requires coordination between the circadian clock (BMAL1) and androgen signaling; NR1D1 (RevErbα) binds the Elovl3 promoter in a circadian-dependent manner in vivo; castration abolishes Elovl3 levels in male liver but not circadian variation, while 5α-dihydrotestosterone induces Elovl3 in female livers and AML12 cells in a time- and androgen receptor-dependent manner.\",\n      \"method\": \"Bmal1 knockout mice; ChIP assay for NR1D1 binding at Elovl3 promoter across circadian time; castration experiments; 5α-dihydrotestosterone injection in female mice; flutamide (androgen receptor antagonist) treatment in AML12 cells; zeitgeber/circadian time series mRNA analysis\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — ChIP demonstrating direct NR1D1 binding, genetic BMAL1 KO, castration/hormone replacement in vivo, and pharmacological AR blockade; multiple orthogonal approaches\",\n      \"pmids\": [\"30862677\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"ELOVL3 ablation reduces meibum melting temperature by ~8°C and increases meibum fluidity, demonstrating that ELOVL3-derived VLCFAs determine the thermotropic/physical properties of meibum; transcriptomic analysis of meibomian glands reveals that ELOVL3 loss dysregulates lipid biosynthesis, inflammation, and stress response gene networks.\",\n      \"method\": \"Elovl3 knockout mice; heat-stage polarized light microscopy for meibum melting temperature; histological examination; MG transcriptome analysis (RNA-seq); slit lamp examination\",\n      \"journal\": \"FASEB journal\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2–3 / Moderate — genetic KO with direct physical measurement of meibum melting properties and transcriptomics; single lab\",\n      \"pmids\": [\"33455016\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"ZHX2 (zinc fingers and homeoboxes 2) transcription factor positively regulates Elovl3 expression in mouse liver; forced Elovl3 expression in human hepatoma cells reduces cell growth and causes cell cycle arrest in S-phase with reduced cyclin mRNA levels, demonstrating that ELOVL3-derived VLCFAs regulate hepatocyte proliferation and cell cycle progression.\",\n      \"method\": \"Mouse microarray and in vivo liver regeneration models; cell-based Elovl3 overexpression in hepatoma lines; cell growth assays; cell synchronization and cell cycle analysis; cyclin mRNA measurement; VLCFA profiling; Zhx2-null mouse livers\",\n      \"journal\": \"American journal of physiology. Gastrointestinal and liver physiology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2–3 / Moderate — forced expression with cell cycle analysis plus genetic mouse models and lipid profiling; single lab\",\n      \"pmids\": [\"37847682\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"Hepatic-specific deletion of Elovl3 (via Cre/LoxP) does not alter body weight, liver mass, liver triglyceride content, lipid profiles, or hepatic lipogenic/oxidative gene expression under normal chow or high-fat diet, demonstrating that hepatic ELOVL3 alone is dispensable for liver lipid homeostasis (negative finding; the anti-obesity phenotype in global KO is attributable to extrahepatic ELOVL3 function).\",\n      \"method\": \"Liver-specific Elovl3 Cre/LoxP knockout mice; high-fat diet challenge; body weight and liver mass measurement; lipidomics; liver triglyceride assay; hepatic gene expression (qRT-PCR and Western blot); glucose tolerance test; ELOVL1 and ELOVL7 expression controls\",\n      \"journal\": \"Biochemical and biophysical research communications\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — rigorous conditional KO with lipidomics and comprehensive metabolic phenotyping; single lab but multiple orthogonal readouts clearly establishing negative result\",\n      \"pmids\": [\"37030067\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"Testosterone/androgen receptor (AR) negatively regulates ELOVL3 transcription through an androgen response element (ARE) in the ELOVL3 promoter; AR overexpression suppresses ELOVL3 promoter activity, and ELOVL3 knockdown reduces lipid droplet accumulation and FASN expression while increasing ATGL mRNA in porcine preadipocytes.\",\n      \"method\": \"Porcine preadipocyte model with testosterone treatment; transcriptomic sequencing; dual-luciferase reporter assay with wild-type and ARE-mutant ELOVL3 promoter; AR overexpression; ELOVL3 siRNA knockdown; lipid droplet staining; FASN and ATGL mRNA analysis\",\n      \"journal\": \"Animals\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2–3 / Moderate — promoter reporter with ARE mutation plus siRNA knockdown and AR overexpression; single lab, multiple complementary methods\",\n      \"pmids\": [\"39123669\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"BAT-specific deletion of Elovl3 causes cold intolerance due to impaired BAT thermogenesis and defective mitochondrial cristae remodeling; lipidomics reveals that Elovl3 deficiency markedly reduces lysophosphatidylcholine, cardiolipin, and acylcarnitine levels in BAT, identifying ELOVL3-derived VLCFAs as required components of BAT phospholipid homeostasis that support UCP1 expression and mitochondrial remodeling during cold adaptation.\",\n      \"method\": \"BAT-specific Elovl3 Cre/LoxP knockout mice; cold exposure challenge; body temperature measurement; Ucp1 expression (qRT-PCR and Western blot); BAT histology; lipidomics analysis; mitochondrial ultrastructure (histological evaluation of cristae remodeling); muscle shivering assessment\",\n      \"journal\": \"Journal of lipid research\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — tissue-specific conditional KO with cold phenotyping, lipidomics, UCP1 expression, and mitochondrial morphology; multiple orthogonal methods in single study\",\n      \"pmids\": [\"41202879\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2026,\n      \"finding\": \"USP25 deubiquitinase binds and stabilizes PARP1 through deubiquitination; PARP1 in turn promotes preadipocyte differentiation and maturation by regulating ELOVL3 expression, placing ELOVL3 downstream of a USP25–PARP1 axis in adipocyte differentiation.\",\n      \"method\": \"Usp25 knockout mice; 3T3-L1 adipocyte differentiation model; RNA sequencing; Co-immunoprecipitation of USP25 and PARP1; ubiquitination assay; PARP1 knockdown with Elovl3 expression readout; adipose tissue histology\",\n      \"journal\": \"Journal of lipid research\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2–3 / Moderate — Co-IP for USP25–PARP1 interaction and ubiquitination assay with genetic KO; ELOVL3 placement is downstream inference from PARP1 manipulation; single lab\",\n      \"pmids\": [\"41692245\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"ELOVL3 is a microsomal fatty acid elongase that catalyzes condensation reactions to extend saturated and monounsaturated fatty acyl-CoAs in the C18–C24 range (producing C20–C24 VLCFAs), functioning critically in sebaceous/meibomian glands, brown and white adipose tissue, and liver; its substrates and products govern skin barrier lipid composition, meibum physical properties, BAT phospholipid homeostasis and mitochondrial cristae remodeling for thermogenesis, and hepatic/adipose triglyceride synthesis, while its transcription is controlled by a network of PPARγ/PPARα, RORγ–BRG1–p300, NR1D1/BMAL1 circadian machinery, androgen/glucocorticoid signaling, SREBP1, VDR, and ZHX2, and ELOVL3-derived C18:1/C20:1 VLCFAs feed back as PPARγ agonists to sustain adipogenesis.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"ELOVL3 is a microsomal fatty acid elongase that catalyzes the condensation step extending saturated and monounsaturated fatty acyl-CoAs into very long chain fatty acids (C20–C24+), governing neutral lipid composition across sebaceous glands, brown and white adipose tissue, liver, and meibomian glands [#0, #1, #6]. Genetic ablation eliminates fatty acids beyond C20 in skin/hair triglycerides and abolishes cold-induced condensation activity for C20:0/C22:0 synthesis in brown adipose tissue, establishing its direct catalytic role [#0, #1]. The VLCFAs it produces are functionally indispensable: in meibomian glands they generate the C21–C29 species (including odd- and branched-chain) of cholesteryl and wax esters that set meibum melting temperature and fluidity [#10, #12], and in brown adipose tissue they sustain lysophosphatidylcholine, cardiolipin, and acylcarnitine pools required for UCP1 expression, mitochondrial cristae remodeling, and cold-adaptive thermogenesis [#16]. ELOVL3-derived VLCFAs also support hepatic triglyceride synthesis, VLDL-TG secretion, and adipose lipid storage, with the systemic anti-obesity phenotype of global knockouts traced to extrahepatic ELOVL3, since hepatocyte-specific deletion leaves liver lipid homeostasis intact [#6, #14]. Transcription of ELOVL3 is integrated by a dense regulatory network: it is induced by PPARγ acting through promoter PPREs during adipogenesis—with ELOVL3-derived C18:1/C20:1 feeding back as PPARγ agonists in a positive loop [#7]—and by PPARα with sympathetic input in brown adipocytes [#2, #4], while being controlled circadianly by SREBP1, NR1D1/RevErbα, and BMAL1 in coordination with androgen signaling [#3, #11], and repressed by VDR and androgen receptor through dedicated promoter response elements [#8, #15]; additional inputs include RORγ–BRG1–p300 epigenetic co-activation and the transcription factor ZHX2, the latter linking ELOVL3 to control of hepatocyte cell-cycle progression [#9, #13].\",\n  \"teleology\": [\n    {\n      \"year\": 2003,\n      \"claim\": \"Established that ELOVL3 is the elongase responsible for synthesizing C20+ fatty acids in skin/hair neutral lipids, defining its core enzymatic identity.\",\n      \"evidence\": \"Elovl3 knockout mice with hair/triglyceride fatty acid profiling and trans-epidermal water loss measurement\",\n      \"pmids\": [\"14581464\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Did not establish substrate chain-length specificity by in vitro assay\", \"Did not address roles outside the pilosebaceous system\"]\n    },\n    {\n      \"year\": 2005,\n      \"claim\": \"Demonstrated direct catalytic condensation activity of ELOVL3 on saturated acyl-CoAs in brown adipose tissue and linked it to cold-stress thermogenesis, extending its function beyond skin.\",\n      \"evidence\": \"In vitro elongation condensation assay on BAT extracts from knockout mice plus cold acclimation phenotyping\",\n      \"pmids\": [\"16326704\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Did not resolve the molecular basis of the thermogenic deficit\", \"Tissue-autonomy of the BAT requirement not established\"]\n    },\n    {\n      \"year\": 2005,\n      \"claim\": \"Placed ELOVL3 in a PPARα-driven, oxidative transcriptional program distinct from LXR/SREBP-1-driven lipogenesis in brown adipocytes.\",\n      \"evidence\": \"Pharmacological ligand treatments in primary brown adipocytes with mRNA and esterified lipid analysis\",\n      \"pmids\": [\"15855229\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No direct promoter occupancy demonstrated\", \"Single lab pharmacological inference\"]\n    },\n    {\n      \"year\": 2006,\n      \"claim\": \"Connected ELOVL3 transcription to circadian and nutritional control via SREBP1 activation and RevErbα repression at its promoter.\",\n      \"evidence\": \"CLOCK-mutant mouse liver analysis with SREBP1/RevErbα promoter reporter assays and meal-restriction experiments\",\n      \"pmids\": [\"17003504\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"In vivo direct binding not shown in this study\", \"Functional lipid consequence of clock disruption not measured\"]\n    },\n    {\n      \"year\": 2007,\n      \"claim\": \"Showed ELOVL3 induction integrates sympathetic and PPARγ signals through both transcription and mRNA stabilization in brown adipocytes.\",\n      \"evidence\": \"Norepinephrine/rosiglitazone treatment of primary brown adipocytes with mRNA stability and cycloheximide experiments\",\n      \"pmids\": [\"17726147\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Did not identify the labile protein required for induction\", \"mRNA stabilization mechanism unresolved\"]\n    },\n    {\n      \"year\": 2008,\n      \"claim\": \"Revealed sexually dimorphic, hormonally controlled circadian regulation of hepatic ELOVL3 and cross-talk with peroxisomal VLCFA oxidation via ABCD2.\",\n      \"evidence\": \"Time-series mRNA profiling, dexamethasone injection, castration, and ABCD2 knockout/transgenic mouse models\",\n      \"pmids\": [\"18292190\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct promoter targets of glucocorticoid/androgen not mapped here\", \"Mechanism of ELOVL3–ABCD2 cross-talk not defined\"]\n    },\n    {\n      \"year\": 2010,\n      \"claim\": \"Defined ELOVL3 as a determinant of systemic lipid handling—hepatic de novo synthesis, VLDL-TG secretion, and adipose expansion—broadening its role to whole-body energy storage.\",\n      \"evidence\": \"Global knockout mice under diet-induced obesity with in vivo fatty acid synthesis, VLDL-TG secretion assays, and tissue histology\",\n      \"pmids\": [\"20605947\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Did not resolve which tissue drives the systemic phenotype\", \"Mechanism linking VLCFA to TG synthesis not detailed\"]\n    },\n    {\n      \"year\": 2012,\n      \"claim\": \"Established a feed-forward loop in which PPARγ directly activates ELOVL3 and ELOVL3-derived C18:1/C20:1 VLCFAs act as PPARγ agonists to sustain adipogenesis.\",\n      \"evidence\": \"ChIP, PPRE-mutant promoter reporters, mammalian two-hybrid, and siRNA rescue in 3T3-L1 cells\",\n      \"pmids\": [\"22436697\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Endogenous VLCFA-PPARγ binding affinity not quantified\", \"Loop dynamics in vivo not established\"]\n    },\n    {\n      \"year\": 2015,\n      \"claim\": \"Identified ELOVL3 as a direct VDR repression target controlling fatty acid composition specifically in subcutaneous white adipose tissue.\",\n      \"evidence\": \"VDR knockout mice with ChIP at a promoter negative-response element and depot-specific lipid profiling\",\n      \"pmids\": [\"26488808\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Physiological trigger for VDR-mediated repression unclear\", \"Depot specificity mechanism unexplained\"]\n    },\n    {\n      \"year\": 2019,\n      \"claim\": \"Demonstrated epigenetic co-activation of ELOVL3 by a RORγ–BRG1–p300 complex in prostate cancer cells responding to androgen and TGF-β.\",\n      \"evidence\": \"BRG1/p300 ChIP, reciprocal Co-IP with RORγ, p300 inhibition, and migration/invasion assays in prostate cancer cells\",\n      \"pmids\": [\"31154107\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Functional contribution of ELOVL3 lipids to cancer phenotype not established\", \"Single lab; cancer-cell context only\"]\n    },\n    {\n      \"year\": 2019,\n      \"claim\": \"Defined ELOVL3's essential catalytic role in meibogenesis, producing the long and odd/branched-chain fatty acids of meibum lipid esters.\",\n      \"evidence\": \"Knockout mice with mass spectrometric lipidomics of tarsal plate lipids\",\n      \"pmids\": [\"31208226\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Functional/optical consequence for tear film not yet measured here\", \"Substrate preference among classes not resolved\"]\n    },\n    {\n      \"year\": 2019,\n      \"claim\": \"Showed sustained rhythmic hepatic ELOVL3 expression requires coordinated BMAL1 circadian and androgen-receptor signaling, with direct NR1D1 promoter binding.\",\n      \"evidence\": \"Bmal1 knockout, circadian NR1D1 ChIP, castration/DHT replacement in vivo, and flutamide treatment in AML12 cells\",\n      \"pmids\": [\"30862677\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Integration of androgen and clock inputs at promoter not fully mechanistic\", \"Downstream lipid consequence of rhythm loss unaddressed\"]\n    },\n    {\n      \"year\": 2021,\n      \"claim\": \"Connected ELOVL3-derived VLCFAs to the physical properties of meibum, showing loss lowers melting temperature and dysregulates gland gene networks.\",\n      \"evidence\": \"Knockout mice with heat-stage polarized light microscopy of meibum melting and meibomian gland RNA-seq\",\n      \"pmids\": [\"33455016\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Causal link between specific lipid species and melting behavior not isolated\", \"In vivo tear-film clinical consequences not measured\"]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Identified ZHX2 as a positive transcriptional regulator and linked ELOVL3-derived VLCFAs to control of hepatocyte cell-cycle progression.\",\n      \"evidence\": \"Zhx2-null mouse livers, liver regeneration models, and hepatoma overexpression with cell cycle and cyclin analysis\",\n      \"pmids\": [\"37847682\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Mechanism linking VLCFA to S-phase arrest unresolved\", \"ZHX2 promoter binding not directly demonstrated\"]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Showed hepatocyte-autonomous ELOVL3 is dispensable for liver lipid homeostasis, attributing the global-KO anti-obesity phenotype to extrahepatic ELOVL3.\",\n      \"evidence\": \"Liver-specific Cre/LoxP knockout with high-fat challenge, lipidomics, and comprehensive metabolic phenotyping\",\n      \"pmids\": [\"37030067\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Did not identify which extrahepatic tissue drives the systemic phenotype\", \"Possible compensation by other elongases not fully excluded\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Demonstrated direct androgen-receptor repression of ELOVL3 through a promoter ARE and its requirement for preadipocyte lipid droplet accumulation.\",\n      \"evidence\": \"ARE-mutant dual-luciferase reporters, AR overexpression, and siRNA knockdown with lipid droplet staining in porcine preadipocytes\",\n      \"pmids\": [\"39123669\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Conservation of ARE regulation across species not established\", \"Mechanism linking ELOVL3 to FASN/ATGL changes unclear\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Established BAT-autonomous ELOVL3 as essential for cold thermogenesis via maintenance of phospholipid pools supporting UCP1 and mitochondrial cristae remodeling.\",\n      \"evidence\": \"BAT-specific Cre/LoxP knockout with cold challenge, lipidomics, UCP1 expression, and mitochondrial ultrastructure\",\n      \"pmids\": [\"41202879\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Direct biochemical link between specific VLCFA species and cristae architecture not isolated\", \"Cardiolipin remodeling mechanism not defined\"]\n    },\n    {\n      \"year\": 2026,\n      \"claim\": \"Placed ELOVL3 downstream of a USP25–PARP1 axis driving preadipocyte differentiation, adding a deubiquitination-dependent regulatory layer.\",\n      \"evidence\": \"Usp25 knockout mice, USP25–PARP1 Co-IP and ubiquitination assays, and PARP1 knockdown with Elovl3 readout in 3T3-L1 cells\",\n      \"pmids\": [\"41692245\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"ELOVL3 placement is inferred downstream of PARP1, not directly mechanistic\", \"Whether PARP1 acts on the ELOVL3 promoter is not shown\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"The structural basis of ELOVL3 substrate selectivity and the precise mechanism by which its VLCFA products shape membrane phospholipid architecture and signaling remain unresolved.\",\n      \"evidence\": \"No structural or reconstituted enzymatic studies present in the corpus\",\n      \"pmids\": [],\n      \"confidence\": \"Low\",\n      \"gaps\": [\"No structural model of the enzyme\", \"Substrate-specificity determinants not mapped\", \"Mechanism by which VLCFAs alter cristae and PPARγ activity not biochemically defined\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0016740\", \"supporting_discovery_ids\": [0, 1, 6, 10, 16]},\n      {\"term_id\": \"GO:0016747\", \"supporting_discovery_ids\": [1]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005783\", \"supporting_discovery_ids\": [0]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-1430728\", \"supporting_discovery_ids\": [0, 1, 6, 16]},\n      {\"term_id\": \"R-HSA-74160\", \"supporting_discovery_ids\": [7, 8, 11, 15]}\n    ],\n    \"complexes\": [],\n    \"partners\": [],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":5,"faith_total":5,"faith_pct":100.0}}