{"gene":"CERS6","run_date":"2026-04-28T17:28:52","timeline":{"discoveries":[{"year":2005,"finding":"CERS6 (Lass6) encodes a ceramide synthase that preferentially synthesizes C14:0 and C16:0 ceramides from saturated/unsaturated fatty acyl-CoA substrates, with substrate preferences distinct from the closely related Lass5. The protein is N-glycosylated at its N-terminal Asn residue, indicating the N-terminus faces the luminal side of the ER membrane, while proteinase K digestion demonstrated the C-terminus faces the cytosolic side.","method":"Overexpression in cultured cells with ceramide species profiling, Northern blotting, glycosylation analysis, proteinase K digestion assay","journal":"The Biochemical journal","confidence":"High","confidence_rationale":"Tier 1 — multiple orthogonal biochemical methods in a single study establishing substrate specificity, glycosylation, and membrane topology","pmids":["15823095"],"is_preprint":false},{"year":2014,"finding":"CerS6 specifically produces C16:0 ceramides in adipose tissue and liver; tissue-specific deletion of CerS6 in brown adipose tissue or liver in mice reduces C16:0 ceramides, increases energy expenditure, improves glucose tolerance, and protects from high-fat-diet-induced obesity, establishing CerS6-derived C16:0 ceramide as a mediator of obesity-associated insulin resistance.","method":"Conditional and global CerS6 knockout mice, ceramide species profiling by mass spectrometry, metabolic phenotyping (glucose/insulin tolerance tests, energy expenditure)","journal":"Cell metabolism","confidence":"High","confidence_rationale":"Tier 2 — multiple tissue-specific KO models with rigorous metabolic phenotyping, replicated across BAT and liver compartments","pmids":["25295788"],"is_preprint":false},{"year":2016,"finding":"CerS6 is a direct transcriptional target of p53; p53 binds within the CerS6 promoter region spanning 91 bp upstream to 60 bp downstream of the transcription start site at a non-canonical p53 response element, and non-genotoxic p53 activation (Nutlin-3 or low-dose actinomycin D) elevates CerS6 mRNA and protein, linking p53 to ceramide biosynthesis and pro-apoptotic response.","method":"Luciferase promoter assays, in vitro immunoprecipitation, electrophoretic mobility shift (gel shift) assay with purified p53, pharmacological p53 activation","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 1 — in vitro binding assays with purified protein plus promoter-reporter and mutagenesis of binding site","pmids":["27302066"],"is_preprint":false},{"year":2019,"finding":"The lncRNA CERS6-AS1 binds to the RNA-binding protein IGF2BP3, and this interaction enhances the stability of CERS6 mRNA, thereby increasing CERS6 protein levels and promoting breast cancer progression.","method":"RNA pulldown, RIP assay, mRNA stability assays, rescue overexpression experiments in vitro and in vivo","journal":"Cancer medicine","confidence":"Medium","confidence_rationale":"Tier 2 — reciprocal pulldown and RIP with functional rescue, single lab","pmids":["31701672"],"is_preprint":false},{"year":2019,"finding":"Antisense oligonucleotide (ASO)-mediated knockdown of CerS6 in liver of obese mice reduces hepatic CerS6 mRNA by ~90% and C16:0 ceramides by ~50% in liver and plasma, and improves glucose tolerance and insulin sensitivity, confirming a causal role for CerS6-derived C16:0 ceramide in insulin resistance.","method":"ASO-mediated in vivo knockdown, ceramide profiling by mass spectrometry, glucose/insulin tolerance tests in ob/ob and HFD mouse models","journal":"Molecular metabolism","confidence":"High","confidence_rationale":"Tier 2 — pharmacological target engagement with ceramide profiling and metabolic phenotyping in two independent disease models","pmids":["30655217"],"is_preprint":false},{"year":2020,"finding":"CERS6 is required for lung cancer cell migration and invasion; CERS6 knockdown alters the ceramide profile, suppresses RAC1-positive lamellipodia/ruffling formation, and attenuates lung metastasis in mice, while forced CERS6 expression has the opposite effect. miR-101 negatively regulates CERS6 expression.","method":"siRNA knockdown, forced overexpression, ceramide profiling, RAC1 imaging, in vivo metastasis assay, luciferase promoter analysis","journal":"Journal of cellular and molecular medicine","confidence":"High","confidence_rationale":"Tier 2 — bidirectional manipulation (KD and OE) with defined cellular phenotype (lamellipodia, metastasis) validated in vivo","pmids":["32902157"],"is_preprint":false},{"year":2021,"finding":"AKT1 phosphorylates FOXP3 at Ser418, reducing FOXP3 binding to the CERS6 promoter and relieving repression of CERS6 transcription; the resulting excess C16:0 ceramide produced by CerS6 promotes accumulation of mutant p53 and pancreatic tumor growth.","method":"Co-immunoprecipitation, kinase assay (AKT1-FOXP3 phosphorylation), ChIP at CERS6 promoter, ceramide profiling, tumor xenograft","journal":"Cancer letters","confidence":"Medium","confidence_rationale":"Tier 2 — CoIP and ChIP establish the AKT1/FOXP3/CERS6 axis, single lab","pmids":["34343636"],"is_preprint":false},{"year":2021,"finding":"CEBPγ transcription factor binds the Y-box cis-element in the CERS6 promoter to activate CERS6 expression, and CEBPγ or YBX1 knockdown independently reduces CERS6 expression, ceramide-dependent lamellipodia formation, and cancer cell migration in NSCLC.","method":"Luciferase promoter analysis, siRNA knockdown, correlation analysis in 149 NSCLC patient datasets, cell migration assays","journal":"Cancer science","confidence":"Medium","confidence_rationale":"Tier 2 — promoter analysis with functional knockdown showing cellular phenotype, single lab","pmids":["33934437"],"is_preprint":false},{"year":2023,"finding":"CERS6 physically interacts with LASP1 (via LASP1's LIM domain), and both co-localize on lamellipodia in lung cancer cells. CERS6 and LASP1 each co-immunoprecipitate with actin, and these interactions are markedly reduced when the LASP1-CERS6 complex is disrupted. C16:0 ceramide partially rescues migration defects caused by silencing of either CERS6 or LASP1, indicating the LASP1-CERS6-actin ternary complex promotes cancer cell migration.","method":"Co-immunoprecipitation, LC-MS/MS interactome, co-localization imaging, siRNA knockdown, C16 ceramide rescue experiments","journal":"Cancers","confidence":"High","confidence_rationale":"Tier 1-2 — reciprocal CoIP confirmed by MS, localization, and functional rescue with defined lipid product","pmids":["37345118"],"is_preprint":false},{"year":2023,"finding":"CerS6 deficiency in hypothalamic neurons (particularly POMC- and SF-1-expressing neurons) attenuates high-fat diet-induced weight gain, improves insulin sensitivity and glucose tolerance, prevents diet-induced mitochondrial morphology alterations, and improves leptin sensitivity, establishing CerS6-derived C16:0 ceramide as a mediator of hypothalamic lipotoxicity and ER/mitochondrial stress.","method":"Conditional (neuron-specific, POMC-Cre, SF-1-Cre) CerS6 knockout mice, metabolic phenotyping, mitochondrial morphology analysis, leptin sensitivity assays, in vitro palmitate treatment of hypothalamic neurons","journal":"Nature communications","confidence":"High","confidence_rationale":"Tier 2 — multiple cell-type-specific KO models with defined metabolic and mitochondrial phenotypes","pmids":["38016943"],"is_preprint":false},{"year":2023,"finding":"CERS6-derived ceramides (d18:1/14:0 and d18:1/16:0) inhibit PINK1-mediated mitophagy in renal tubular epithelial cells, possibly by binding to the PINK1 protein (supported by automated docking), leading to accumulation of damaged mitochondria and exacerbation of renal interstitial fibrosis in diabetic kidney disease. PINK1 inhibition in CERS6 knockdown cells diminished the protective effect.","method":"CerS6 knockout and knockdown in db/db mice and HK-2 cells, ceramide profiling by LC-MS/MS, mitophagy assays, molecular docking, PINK1 inhibition rescue experiment","journal":"American journal of physiology. Cell physiology","confidence":"Medium","confidence_rationale":"Tier 2 — in vivo KO with in vitro mechanistic follow-up; direct ceramide-PINK1 binding is computational only","pmids":["37458434"],"is_preprint":false},{"year":2023,"finding":"CerS6-derived ceramide (d18:1/16:0) binds to the mitochondrial channel protein VDAC1 at Glu59, initiating mitochondrial DNA leakage and activating the cGAS-STING innate immune signaling pathway in podocytes, thereby promoting inflammatory responses in diabetic kidney disease.","method":"Podocyte-specific CerS6 knockout and overexpression mice, ceramide-VDAC1 binding analysis (with Glu59 site identified), mtDNA leakage assay, cGAS-STING pathway analysis","journal":"Nature communications","confidence":"High","confidence_rationale":"Tier 1-2 — bidirectional genetic manipulation (KO and OE) in vivo with defined molecular mechanism (ceramide-VDAC1 interaction at specific residue) and downstream pathway activation","pmids":["39934147"],"is_preprint":false},{"year":2023,"finding":"High glucose promotes CerS6 synthesis through the TLR4/IKKβ signaling pathway; CerS6-derived C16:0 ceramide accumulates in mitochondria and promotes mitochondrial oxidative stress (mtROS), which triggers ferroptosis and liver cell injury. CerS6 knockdown attenuates mtROS and ferroptosis, while CerS6 overexpression exacerbates these effects, reversed by mitochondria-targeted antioxidant Mito-TEMPO.","method":"CerS6 knockout and overexpression in LO2 cells, TLR4/IKKβ pathway inhibition, mitochondrial ROS measurement, ferroptosis markers, Mito-TEMPO rescue","journal":"Molecular and cellular endocrinology","confidence":"Medium","confidence_rationale":"Tier 2 — bidirectional manipulation with pathway inhibition rescue, single lab","pmids":["37230220"],"is_preprint":false},{"year":2023,"finding":"CerS6-derived C16:0 ceramide promotes lipid droplet biogenesis in hepatocytes during alcohol-associated liver disease; CerS6 deletion decreases PLIN2 (perilipin 2) protein expression in EtOH-fed mice and cells, and exogenous C16:0 ceramide treatment increases PLIN2 protein, establishing a CerS6/ceramide/PLIN2 axis in hepatic steatosis.","method":"CerS6 KO mice (both sexes) on ethanol diet, RNAseq, in vitro CerS6 deletion in VL17A hepatocytes, C16:0 ceramide treatment, PLIN2 protein analysis","journal":"Molecular metabolism","confidence":"Medium","confidence_rationale":"Tier 2 — KO in vivo and in vitro with ceramide supplementation rescue, single lab","pmids":["37714377"],"is_preprint":false},{"year":2024,"finding":"FTO (m6A demethylase) deficiency increases m6A modification on CERS6 mRNA, decreasing its stability and downregulating CerS6 expression in intestinal epithelial cells (IECs); this leads to accumulation of sphingosine-1-phosphate (S1P), which triggers proinflammatory macrophage activation and Th17 cell differentiation, exacerbating ulcerative colitis.","method":"Fto intestinal epithelial-specific knockout mice with DSS colitis, RNA and methylated RNA immunoprecipitation sequencing (RIP-seq), m6A profiling, conditioned medium macrophage experiments, LC-MS ceramide/S1P quantification","journal":"Gut","confidence":"High","confidence_rationale":"Tier 2 — conditional KO with m6A sequencing and multiple downstream mechanistic validations in vivo and in vitro","pmids":["37734910"],"is_preprint":false},{"year":2024,"finding":"CD36 regulates CerS6 protein stability; CD36 deficiency leads to accelerated CerS6 protein degradation, reduced C16:0 ceramide production, and attenuated LPS-induced inflammatory responses (MAPK, NF-κB, inflammasome activation). CerS6-derived C16:0 ceramide augments inflammatory responses through ER stress induction.","method":"CD36 knockout mice, CerS6 protein stability assay, LPS-induced inflammation in vitro and in vivo, cytokine measurement, inflammasome analysis","journal":"International immunopharmacology","confidence":"Medium","confidence_rationale":"Tier 2 — KO model with protein stability analysis and pathway characterization, single lab","pmids":["39461238"],"is_preprint":false},{"year":2024,"finding":"Stress-induced corticosterone (CORT) activates the AMPK/p38 MAPK pathway to upregulate CerS6, increasing mitochondrial C16:0 ceramide; CerS6 knockdown in hepatocytes inhibits CORT-induced C16:0 ceramide elevation and mitochondrial cytochrome c release, while p38 MAPK inhibition (SB203580) attenuates CORT-induced CerS6 protein upregulation.","method":"Rat restraint stress model, CORT-treated hepatocytes, CerS6 knockdown, ceramide profiling by LC-MS/MS, mitochondrial isolation, cytochrome c release, kinase pathway inhibitor experiments","journal":"Lipids in health and disease","confidence":"Medium","confidence_rationale":"Tier 2 — in vivo and in vitro models with pathway inhibitor rescue, single lab","pmids":["38431645"],"is_preprint":false},{"year":2022,"finding":"Casein kinase 2α (CK2α) phosphorylates the C-terminal region of CerS6 to increase its enzymatic activity; the herbal compound DHG reduces CK2α protein expression and promotes CerS6 protein degradation (demonstrated by cycloheximide assay), thereby decreasing C16:0 ceramide in NASH.","method":"Cycloheximide protein stability assay in vitro, western blotting, CK2α expression analysis, ceramide profiling by HPLC-QQQ-MS/MS in rat NASH model","journal":"Journal of ethnopharmacology","confidence":"Medium","confidence_rationale":"Tier 3 — CHX stability assay for degradation and CK2α-CerS6 phosphorylation relationship established, single lab","pmids":["35654350"],"is_preprint":false},{"year":2025,"finding":"CBX4 indirectly activates CERS6 transcription by suppressing HDAC5 expression; HDAC5 directly targets the CERS6 promoter (confirmed by dual-luciferase reporter assay and ChIP), and CBX4 knockdown downregulates CERS6 mRNA and protein while activating PI3K/AKT and MAPK signaling in AML cells.","method":"siRNA knockdown, chromatin immunoprecipitation (ChIP), dual-luciferase reporter assay, RNA sequencing, proteomics, lipidomics in THP-1 and KG-1 AML cell lines","journal":"American journal of cancer research","confidence":"Medium","confidence_rationale":"Tier 2 — ChIP and dual-luciferase reporter establish direct HDAC5-CERS6 promoter interaction, single lab","pmids":["41395279"],"is_preprint":false},{"year":2025,"finding":"E4BP4 acts as a transcriptional repressor of Cers6 by binding to an enhancer region ~65 kb upstream of the Cers6 gene in brown adipose tissue, interacting with PRDM16 to suppress Cers6 mRNA expression and reduce C16:0 ceramide levels, thereby preventing obesity-induced mitochondrial fragmentation in BAT.","method":"E4BP4 gain-of-function in BAT, Cers6 mRNA quantification, C16:0 ceramide measurement, mitochondrial morphology analysis, E4BP4-PRDM16 interaction, enhancer binding assay","journal":"bioRxiv","confidence":"Medium","confidence_rationale":"Tier 2 — preprint with gain-of-function and enhancer binding data, not yet peer-reviewed","pmids":["bio_10.1101_2025.05.19.652826"],"is_preprint":true},{"year":2025,"finding":"CERS6 sustains the stability of ribophorin 1 (RPN1) by inhibiting its ubiquitination; this activates the RPN1-IRE1-XBP1 ER stress signaling pathway to reduce ER stress and ROS, promoting ESCC cell proliferation. This represents a ceramide-synthesis-independent function of CERS6.","method":"CERS6 overexpression and knockdown in ESCC cells and xenografts, ubiquitination assay for RPN1, ASO targeting of CERS6, IRE1-XBP1 pathway analysis","journal":"Cell death discovery","confidence":"Medium","confidence_rationale":"Tier 2 — ubiquitination assay with bidirectional manipulation and pathway analysis, single lab, novel non-canonical function","pmids":["41203639"],"is_preprint":false}],"current_model":"CERS6 is an endoplasmic reticulum-resident ceramide synthase with a cytosol-facing C-terminus and lumen-facing N-terminus (N-glycosylated) that preferentially produces C14:0 and C16:0 ceramides from fatty acyl-CoA substrates; its transcription is directly activated by p53, CEBPγ, and the AKT1/FOXP3 axis, and repressed by E4BP4/PRDM16 and miR-101, while its protein stability is regulated by CD36 and CK2α-mediated phosphorylation; the resulting C16:0 ceramides drive metabolic dysfunction (obesity, insulin resistance, mitochondrial fragmentation, ER stress) by binding VDAC1 to trigger cGAS-STING inflammation and inhibiting PINK1-mediated mitophagy, and promote cancer cell migration through a LASP1-CERS6-actin ternary complex that drives RAC1-dependent lamellipodia formation."},"narrative":{"teleology":[{"year":2005,"claim":"Identification of CERS6 as a ceramide synthase with C14:0/C16:0 acyl-CoA specificity and defined ER membrane topology resolved which enzyme produces these specific ceramide species and how it is oriented in the membrane.","evidence":"Overexpression with ceramide species profiling, glycosylation analysis, and proteinase K digestion in cultured cells","pmids":["15823095"],"confidence":"High","gaps":["No crystal structure available","Determinants of acyl-CoA selectivity not mapped to specific residues","Regulation of enzymatic activity unknown at this stage"]},{"year":2014,"claim":"Tissue-specific knockout of CerS6 in adipose and liver demonstrated that CerS6-derived C16:0 ceramide is causally required for diet-induced obesity and insulin resistance, establishing the enzyme as a metabolic disease driver rather than merely a biosynthetic enzyme.","evidence":"Conditional CerS6 knockout mice (BAT-Cre, liver-Cre) with metabolic phenotyping and ceramide mass spectrometry","pmids":["25295788"],"confidence":"High","gaps":["Downstream lipid effector mechanism (how C16:0 ceramide causes insulin resistance) not identified","CNS contribution unknown"]},{"year":2016,"claim":"Discovery that p53 directly binds a non-canonical response element in the CERS6 promoter connected tumor suppressor signaling to ceramide biosynthesis, providing a transcriptional mechanism for stress-induced ceramide elevation.","evidence":"Purified p53 gel-shift assay, luciferase promoter reporters with mutagenesis, pharmacological p53 activation","pmids":["27302066"],"confidence":"High","gaps":["Physiological relevance of p53-CERS6 axis in vivo not tested","Other stress-responsive transcription factors not yet characterized"]},{"year":2019,"claim":"ASO-mediated hepatic CerS6 knockdown replicated KO metabolic benefits in obese mice, validating CerS6 as a druggable therapeutic target for insulin resistance.","evidence":"ASO knockdown in ob/ob and HFD mouse models with ceramide profiling and metabolic tests","pmids":["30655217"],"confidence":"High","gaps":["Long-term safety and off-target sphingolipid effects not assessed","Mechanism downstream of C16:0 ceramide reduction still undefined"]},{"year":2020,"claim":"CERS6 was shown to be required for RAC1-dependent lamellipodia formation and lung cancer metastasis, establishing a pro-migratory function beyond metabolic roles, with miR-101 identified as a negative regulator.","evidence":"Bidirectional manipulation (siRNA KD and overexpression) with RAC1 imaging and in vivo metastasis assay in lung cancer cells","pmids":["32902157"],"confidence":"High","gaps":["Whether migration depends on ceramide product or CERS6 protein scaffolding was unclear","Direct miR-101 binding site not validated by mutagenesis"]},{"year":2021,"claim":"Identification of additional transcriptional regulators (AKT1/FOXP3 axis and CEBPγ/YBX1) at the CERS6 promoter revealed that CERS6 is a convergence node for oncogenic kinase and transcription factor inputs in cancer.","evidence":"ChIP at CERS6 promoter for FOXP3, AKT1 kinase assay, luciferase reporter with CEBPγ binding, siRNA knockdown in NSCLC and pancreatic cancer lines","pmids":["34343636","33934437"],"confidence":"Medium","gaps":["Combinatorial regulation by multiple factors not tested","FOXP3 and CEBPγ studies each from single labs","In vivo ChIP confirmation lacking for CEBPγ"]},{"year":2022,"claim":"CK2α-mediated phosphorylation of CERS6's C-terminal region was shown to enhance its enzymatic activity and protein stability, providing the first post-translational regulatory mechanism for CERS6.","evidence":"Cycloheximide stability assay, CK2α expression analysis, ceramide profiling in NASH rat model","pmids":["35654350"],"confidence":"Medium","gaps":["Specific phosphorylation sites not mapped","Direct in vitro kinase assay with purified proteins not performed","Single lab, single disease model"]},{"year":2023,"claim":"The LASP1–CERS6–actin ternary complex was identified at lamellipodia, resolving that CERS6 has a scaffolding function in cell migration beyond ceramide production, with C16:0 ceramide partially rescuing migration when the complex is disrupted.","evidence":"Reciprocal co-IP confirmed by LC-MS/MS, co-localization imaging, siRNA with C16:0 ceramide rescue","pmids":["37345118"],"confidence":"High","gaps":["Structural basis of LASP1–CERS6 interaction beyond LIM domain requirement unknown","Whether ceramide is produced locally at lamellipodia not demonstrated"]},{"year":2023,"claim":"Multiple 2023 studies defined downstream effectors of CerS6-derived C16:0 ceramide in distinct tissues: binding VDAC1 at Glu59 to trigger mtDNA leakage and cGAS–STING inflammation in podocytes, inhibiting PINK1-mediated mitophagy in renal tubular cells, inducing mitochondrial ROS and ferroptosis in hepatocytes, and mediating hypothalamic lipotoxicity.","evidence":"Podocyte- and neuron-specific CerS6 KO mice, ceramide-VDAC1 binding analysis, mitophagy and ferroptosis assays, mitochondrial morphology analysis","pmids":["39934147","37458434","37230220","38016943"],"confidence":"High","gaps":["Direct PINK1-ceramide binding is computational only (docking)","Whether VDAC1 binding occurs in non-renal tissues not established","Ferroptosis mechanism awaits genetic validation of ferroptosis markers"]},{"year":2024,"claim":"m6A modification was identified as a post-transcriptional control point for CERS6 mRNA stability, with FTO deficiency increasing m6A on CERS6 mRNA and reducing its expression; CD36 was separately shown to stabilize CerS6 protein, expanding the repertoire of CERS6 regulation to epitranscriptomic and membrane receptor-mediated mechanisms.","evidence":"FTO intestinal epithelial-specific KO with RIP-seq and m6A profiling; CD36 KO with protein stability assays","pmids":["37734910","39461238"],"confidence":"High","gaps":["Specific m6A reader protein acting on CERS6 mRNA not identified","Mechanism by which CD36 stabilizes CerS6 protein unknown","Whether these regulatory modes operate in metabolic tissues beyond gut and macrophages unclear"]},{"year":2025,"claim":"A ceramide-synthesis-independent function of CERS6 was discovered: CERS6 stabilizes RPN1 by inhibiting its ubiquitination, activating IRE1–XBP1 ER stress signaling to promote ESCC cell proliferation, demonstrating that CERS6 has non-enzymatic roles.","evidence":"CERS6 overexpression/knockdown with ubiquitination assays for RPN1, ASO targeting, IRE1–XBP1 pathway analysis in ESCC cells and xenografts","pmids":["41203639"],"confidence":"Medium","gaps":["The structural domain of CERS6 mediating RPN1 interaction is unmapped","Whether this non-enzymatic function operates in non-cancer cells is unknown","Single lab, not independently confirmed"]},{"year":null,"claim":"Key unresolved questions include the structural basis of CERS6 acyl-CoA selectivity, whether the enzymatic and scaffolding functions are separable in vivo, whether C16:0 ceramide produced by CERS6 acts locally at specific organelle contact sites, and whether combinatorial transcriptional/post-translational inputs are integrated in physiological settings.","evidence":"","pmids":[],"confidence":"Low","gaps":["No high-resolution structure of CERS6","No separation-of-function mutant distinguishing catalytic and scaffolding roles","Organelle-specific ceramide pools not resolved in vivo"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0016740","term_label":"transferase activity","supporting_discovery_ids":[0,1,4]},{"term_id":"GO:0008289","term_label":"lipid binding","supporting_discovery_ids":[0]},{"term_id":"GO:0098772","term_label":"molecular function regulator activity","supporting_discovery_ids":[20]}],"localization":[{"term_id":"GO:0005783","term_label":"endoplasmic reticulum","supporting_discovery_ids":[0]},{"term_id":"GO:0005886","term_label":"plasma membrane","supporting_discovery_ids":[8]},{"term_id":"GO:0005739","term_label":"mitochondrion","supporting_discovery_ids":[9,11,12]}],"pathway":[{"term_id":"R-HSA-1430728","term_label":"Metabolism","supporting_discovery_ids":[0,1,4,9,13]},{"term_id":"R-HSA-168256","term_label":"Immune System","supporting_discovery_ids":[11,14,15]},{"term_id":"R-HSA-5357801","term_label":"Programmed Cell Death","supporting_discovery_ids":[10,12]},{"term_id":"R-HSA-162582","term_label":"Signal Transduction","supporting_discovery_ids":[6,11,16]},{"term_id":"R-HSA-8953897","term_label":"Cellular responses to stimuli","supporting_discovery_ids":[9,12,15,20]}],"complexes":["LASP1-CERS6-actin ternary complex"],"partners":["LASP1","VDAC1","RPN1","CD36","FOXP3","IGF2BP3","CERS6-AS1"],"other_free_text":[]},"mechanistic_narrative":"CERS6 is an endoplasmic reticulum-resident ceramide synthase that preferentially generates C14:0 and C16:0 ceramides and functions as a central node linking sphingolipid metabolism to energy homeostasis, inflammation, and cell migration. The enzyme is N-glycosylated at its luminal N-terminus and possesses a cytosol-facing C-terminus; its transcription is directly activated by p53 and CEBPγ and repressed by FOXP3 and HDAC5, while its mRNA stability is regulated by m6A modification and the lncRNA CERS6-AS1/IGF2BP3 axis, and its protein turnover is controlled by CD36 and CK2α-mediated phosphorylation [PMID:15823095, PMID:27302066, PMID:33934437, PMID:34343636, PMID:37734910, PMID:39461238, PMID:35654350, PMID:41395279]. CerS6-derived C16:0 ceramide drives obesity-associated insulin resistance and mitochondrial dysfunction across adipose, liver, and hypothalamic compartments, and triggers inflammatory signaling by binding VDAC1 at Glu59 to cause mitochondrial DNA leakage and cGAS–STING activation, or by inducing ER stress [PMID:25295788, PMID:38016943, PMID:39934147, PMID:37230220]. In cancer cells, CERS6 forms a ternary complex with LASP1 and actin at lamellipodia to promote RAC1-dependent migration and metastasis, and additionally stabilizes RPN1 to modulate ER stress through a ceramide-synthesis-independent mechanism [PMID:37345118, PMID:32902157, PMID:41203639]."},"prefetch_data":{"uniprot":{"accession":"Q6ZMG9","full_name":"Ceramide synthase 6","aliases":["LAG1 longevity assurance homolog 6","Sphingoid base N-palmitoyltransferase CERS6"],"length_aa":384,"mass_kda":44.9,"function":"Ceramide synthase that catalyzes the transfer of the acyl chain from acyl-CoA to a sphingoid base, with high selectivity toward palmitoyl-CoA (hexadecanoyl-CoA; C16:0-CoA) (PubMed:17609214, PubMed:17977534, PubMed:23530041, PubMed:26887952, PubMed:31916624, PubMed:39528795). Can use other acyl donors, but with less efficiency (PubMed:39528795). N-acylates sphinganine and sphingosine bases to form dihydroceramides and ceramides in de novo synthesis and salvage pathways, respectively (PubMed:17977534, PubMed:23530041, PubMed:26887952, PubMed:31916624). Ceramides generated by CERS6 play a role in inflammatory response (By similarity). Acts as a regulator of metabolism and hepatic lipid accumulation (By similarity). Under high fat diet, palmitoyl- (C16:0-) ceramides generated by CERS6 specifically bind the mitochondrial fission factor MFF, thereby promoting mitochondrial fragmentation and contributing to the development of obesity (By similarity)","subcellular_location":"Endoplasmic reticulum membrane","url":"https://www.uniprot.org/uniprotkb/Q6ZMG9/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/CERS6","classification":"Not Classified","n_dependent_lines":3,"n_total_lines":1208,"dependency_fraction":0.0024834437086092716},"opencell":{"profiled":true,"resolved_as":"","ensg_id":"ENSG00000172292","cell_line_id":"CID001010","localizations":[{"compartment":"er","grade":3}],"interactors":[{"gene":"TMEM57","stoichiometry":10.0},{"gene":"LMAN2L","stoichiometry":4.0},{"gene":"ST7","stoichiometry":0.2},{"gene":"CANX","stoichiometry":0.2}],"url":"https://opencell.sf.czbiohub.org/target/CID001010","total_profiled":1310},"omim":[{"mim_id":"619822","title":"BCL2-LIKE 13; BCL2L13","url":"https://www.omim.org/entry/619822"},{"mim_id":"615336","title":"CERAMIDE SYNTHASE 6; CERS6","url":"https://www.omim.org/entry/615336"},{"mim_id":"615335","title":"CERAMIDE SYNTHASE 5; CERS5","url":"https://www.omim.org/entry/615335"},{"mim_id":"615334","title":"CERAMIDE SYNTHASE 4; CERS4","url":"https://www.omim.org/entry/615334"},{"mim_id":"606920","title":"CERAMIDE SYNTHASE 2; CERS2","url":"https://www.omim.org/entry/606920"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"","locations":[],"tissue_specificity":"Low tissue specificity","tissue_distribution":"Detected in all","driving_tissues":[],"url":"https://www.proteinatlas.org/search/CERS6"},"hgnc":{"alias_symbol":[],"prev_symbol":["LASS6"]},"alphafold":{"accession":"Q6ZMG9","domains":[{"cath_id":"1.10.10.60","chopping":"80-123","consensus_level":"high","plddt":94.5259,"start":80,"end":123},{"cath_id":"-","chopping":"129-331","consensus_level":"high","plddt":96.4705,"start":129,"end":331}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q6ZMG9","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q6ZMG9-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q6ZMG9-F1-predicted_aligned_error_v6.png","plddt_mean":86.81},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=CERS6","jax_strain_url":"https://www.jax.org/strain/search?query=CERS6"},"sequence":{"accession":"Q6ZMG9","fasta_url":"https://rest.uniprot.org/uniprotkb/Q6ZMG9.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q6ZMG9/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q6ZMG9"}},"corpus_meta":[{"pmid":"25295788","id":"PMC_25295788","title":"Obesity-induced CerS6-dependent C16:0 ceramide production promotes weight gain and glucose intolerance.","date":"2014","source":"Cell metabolism","url":"https://pubmed.ncbi.nlm.nih.gov/25295788","citation_count":586,"is_preprint":false},{"pmid":"15823095","id":"PMC_15823095","title":"Mammalian Lass6 and its related family members regulate synthesis of specific ceramides.","date":"2005","source":"The Biochemical journal","url":"https://pubmed.ncbi.nlm.nih.gov/15823095","citation_count":334,"is_preprint":false},{"pmid":"30655217","id":"PMC_30655217","title":"The role of C16:0 ceramide in the development of obesity and type 2 diabetes: CerS6 inhibition as a novel therapeutic approach.","date":"2019","source":"Molecular metabolism","url":"https://pubmed.ncbi.nlm.nih.gov/30655217","citation_count":161,"is_preprint":false},{"pmid":"31701672","id":"PMC_31701672","title":"Long noncoding RNA CERS6-AS1 functions as a malignancy promoter in breast cancer by binding to IGF2BP3 to enhance the stability of CERS6 mRNA.","date":"2019","source":"Cancer medicine","url":"https://pubmed.ncbi.nlm.nih.gov/31701672","citation_count":58,"is_preprint":false},{"pmid":"37734910","id":"PMC_37734910","title":"Disruption of CerS6-mediated sphingolipid metabolism by FTO deficiency aggravates ulcerative colitis.","date":"2024","source":"Gut","url":"https://pubmed.ncbi.nlm.nih.gov/37734910","citation_count":46,"is_preprint":false},{"pmid":"27302066","id":"PMC_27302066","title":"CerS6 Is a Novel Transcriptional Target of p53 Protein Activated by Non-genotoxic Stress.","date":"2016","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/27302066","citation_count":45,"is_preprint":false},{"pmid":"30054909","id":"PMC_30054909","title":"CerS6 regulates cisplatin resistance in oral squamous cell carcinoma by altering mitochondrial fission and autophagy.","date":"2018","source":"Journal of cellular physiology","url":"https://pubmed.ncbi.nlm.nih.gov/30054909","citation_count":42,"is_preprint":false},{"pmid":"34168120","id":"PMC_34168120","title":"LncRNA CERS6-AS1 promotes proliferation and metastasis through the upregulation of YWHAG and activation of ERK signaling in pancreatic cancer.","date":"2021","source":"Cell death & disease","url":"https://pubmed.ncbi.nlm.nih.gov/34168120","citation_count":38,"is_preprint":false},{"pmid":"38016943","id":"PMC_38016943","title":"CerS6-dependent ceramide synthesis in hypothalamic neurons promotes ER/mitochondrial stress and impairs glucose homeostasis in obese mice.","date":"2023","source":"Nature communications","url":"https://pubmed.ncbi.nlm.nih.gov/38016943","citation_count":34,"is_preprint":false},{"pmid":"37458434","id":"PMC_37458434","title":"CERS6-derived ceramides aggravate kidney fibrosis by inhibiting PINK1-mediated mitophagy in diabetic kidney disease.","date":"2023","source":"American journal of physiology. Cell physiology","url":"https://pubmed.ncbi.nlm.nih.gov/37458434","citation_count":30,"is_preprint":false},{"pmid":"34343636","id":"PMC_34343636","title":"AKT1/FOXP3 axis-mediated expression of CerS6 promotes p53 mutant pancreatic tumorigenesis.","date":"2021","source":"Cancer letters","url":"https://pubmed.ncbi.nlm.nih.gov/34343636","citation_count":27,"is_preprint":false},{"pmid":"32808708","id":"PMC_32808708","title":"lncRNA CERS6-AS1 as ceRNA promote cell proliferation of breast cancer by sponging miR-125a-5p to upregulate BAP1 expression.","date":"2020","source":"Molecular carcinogenesis","url":"https://pubmed.ncbi.nlm.nih.gov/32808708","citation_count":26,"is_preprint":false},{"pmid":"39934147","id":"PMC_39934147","title":"CerS6 links ceramide metabolism to innate immune responses in diabetic kidney disease.","date":"2025","source":"Nature communications","url":"https://pubmed.ncbi.nlm.nih.gov/39934147","citation_count":21,"is_preprint":false},{"pmid":"32902157","id":"PMC_32902157","title":"CERS6 required for cell migration and metastasis in lung cancer.","date":"2020","source":"Journal of cellular and molecular medicine","url":"https://pubmed.ncbi.nlm.nih.gov/32902157","citation_count":21,"is_preprint":false},{"pmid":"26934938","id":"PMC_26934938","title":"Silencing of CerS6 increases the invasion and glycolysis of melanoma WM35, WM451 and SK28 cell lines via increased GLUT1-induced downregulation of WNT5A.","date":"2016","source":"Oncology reports","url":"https://pubmed.ncbi.nlm.nih.gov/26934938","citation_count":21,"is_preprint":false},{"pmid":"16211262","id":"PMC_16211262","title":"LASS6, an additional member of the longevity assurance gene family.","date":"2005","source":"International journal of molecular medicine","url":"https://pubmed.ncbi.nlm.nih.gov/16211262","citation_count":17,"is_preprint":false},{"pmid":"33581689","id":"PMC_33581689","title":"Long non-coding RNA CERS6-AS1 facilitates the oncogenicity of pancreatic ductal adenocarcinoma by regulating the microRNA-15a-5p/FGFR1 axis.","date":"2021","source":"Aging","url":"https://pubmed.ncbi.nlm.nih.gov/33581689","citation_count":17,"is_preprint":false},{"pmid":"33939677","id":"PMC_33939677","title":"Long Noncoding RNA CERS6-AS1 Accelerates the Proliferation and Migration of Pancreatic Cancer Cells by Sequestering MicroRNA-15a-5p and MicroRNA-6838-5p and Modulating HMGA1.","date":"2021","source":"Pancreas","url":"https://pubmed.ncbi.nlm.nih.gov/33939677","citation_count":17,"is_preprint":false},{"pmid":"35702784","id":"PMC_35702784","title":"IGF2BP3 Worsens Lung Cancer through Modifying Long Non-coding RNA CERS6-AS1/microRNA-1202 Axis.","date":"2023","source":"Current medicinal chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/35702784","citation_count":16,"is_preprint":false},{"pmid":"33934437","id":"PMC_33934437","title":"CEBPγ facilitates lamellipodia formation and cancer cell migration through CERS6 upregulation.","date":"2021","source":"Cancer science","url":"https://pubmed.ncbi.nlm.nih.gov/33934437","citation_count":15,"is_preprint":false},{"pmid":"35146902","id":"PMC_35146902","title":"CERS6-AS1 contributes to the malignant phenotypes of colorectal cancer cells by interacting with miR-15b-5p to regulate SPTBN2.","date":"2022","source":"The Kaohsiung journal of medical sciences","url":"https://pubmed.ncbi.nlm.nih.gov/35146902","citation_count":14,"is_preprint":false},{"pmid":"35777805","id":"PMC_35777805","title":"CERS6-AS1 Facilitates Oncogenesis and Restrains Ferroptosis in Papillary Thyroid Carcinoma by Serving as a ceRNA through miR-497-5p/LASP1 Axis.","date":"2022","source":"Annals of clinical and laboratory science","url":"https://pubmed.ncbi.nlm.nih.gov/35777805","citation_count":12,"is_preprint":false},{"pmid":"35654350","id":"PMC_35654350","title":"Danhe granule ameliorates nonalcoholic steatohepatitis and fibrosis in rats by inhibiting ceramide de novo synthesis related to CerS6 and CerK.","date":"2022","source":"Journal of ethnopharmacology","url":"https://pubmed.ncbi.nlm.nih.gov/35654350","citation_count":12,"is_preprint":false},{"pmid":"38094657","id":"PMC_38094657","title":"lncRNA CERS6-AS1 upregulates the expression of ANLN by sponging miR-424-5p to promote the progression and drug resistance of lung adenocarcinoma.","date":"2023","source":"Non-coding RNA research","url":"https://pubmed.ncbi.nlm.nih.gov/38094657","citation_count":12,"is_preprint":false},{"pmid":"35199935","id":"PMC_35199935","title":"CERS6-AS1 promotes cell proliferation and represses cell apoptosis in pancreatic cancer via miR-195-5p/WIPI2 axis.","date":"2022","source":"The Kaohsiung journal of medical sciences","url":"https://pubmed.ncbi.nlm.nih.gov/35199935","citation_count":12,"is_preprint":false},{"pmid":"37230220","id":"PMC_37230220","title":"CerS6 triggered by high glucose activating the TLR4/IKKβ pathway regulates ferroptosis of LO2 cells through mitochondrial oxidative stress.","date":"2023","source":"Molecular and cellular endocrinology","url":"https://pubmed.ncbi.nlm.nih.gov/37230220","citation_count":11,"is_preprint":false},{"pmid":"35927226","id":"PMC_35927226","title":"Long noncoding RNA CERS6-AS1 modulates glucose metabolism and tumor progression in hepatocellular carcinoma by promoting the MDM2/p53 signaling pathway.","date":"2022","source":"Cell death discovery","url":"https://pubmed.ncbi.nlm.nih.gov/35927226","citation_count":11,"is_preprint":false},{"pmid":"37714377","id":"PMC_37714377","title":"Ceramide synthase 6 (CerS6) is upregulated in alcohol-associated liver disease and exhibits sex-based differences in the regulation of energy homeostasis and lipid droplet accumulation.","date":"2023","source":"Molecular metabolism","url":"https://pubmed.ncbi.nlm.nih.gov/37714377","citation_count":9,"is_preprint":false},{"pmid":"39488053","id":"PMC_39488053","title":"Machine learning model identifies genetic predictors of cisplatin-induced ototoxicity in CERS6 and TLR4.","date":"2024","source":"Computers in biology and medicine","url":"https://pubmed.ncbi.nlm.nih.gov/39488053","citation_count":7,"is_preprint":false},{"pmid":"36580796","id":"PMC_36580796","title":"The role of lncRNA CERS6-AS1 in cancer and its molecular mechanisms: A systematic review and meta-analysis.","date":"2022","source":"Pathology, research and practice","url":"https://pubmed.ncbi.nlm.nih.gov/36580796","citation_count":6,"is_preprint":false},{"pmid":"37345118","id":"PMC_37345118","title":"LASP1, CERS6, and Actin Form a Ternary Complex That Promotes Cancer Cell Migration.","date":"2023","source":"Cancers","url":"https://pubmed.ncbi.nlm.nih.gov/37345118","citation_count":6,"is_preprint":false},{"pmid":"37130182","id":"PMC_37130182","title":"MYC-activated CERS6-AS1 sponges miR-6838-5p and regulates the expression of RUBCNL in colorectal cancer.","date":"2022","source":"Cellular and molecular biology (Noisy-le-Grand, France)","url":"https://pubmed.ncbi.nlm.nih.gov/37130182","citation_count":5,"is_preprint":false},{"pmid":"39461238","id":"PMC_39461238","title":"CD36 deficiency protects lipopolysaccharide-induced sepsis via inhibiting CerS6-mediated endoplasmic reticulum stress.","date":"2024","source":"International immunopharmacology","url":"https://pubmed.ncbi.nlm.nih.gov/39461238","citation_count":4,"is_preprint":false},{"pmid":"35706508","id":"PMC_35706508","title":"Effect and Mechanism of lncRNA CERS6-AS1 on the Biological Behavior of Prostate Cancer Cell.","date":"2022","source":"Applied bionics and biomechanics","url":"https://pubmed.ncbi.nlm.nih.gov/35706508","citation_count":4,"is_preprint":false},{"pmid":"36628448","id":"PMC_36628448","title":"CERS6 antisense RNA 1 promotes colon cancer via upregulating mitochondrial calcium uniporter.","date":"2023","source":"European journal of clinical investigation","url":"https://pubmed.ncbi.nlm.nih.gov/36628448","citation_count":4,"is_preprint":false},{"pmid":"36889776","id":"PMC_36889776","title":"LncRNA CERS6-AS1 Is a Tumor Promoter in Cervical Cancer by Sponging miR-195-5p.","date":"2023","source":"Annals of clinical and laboratory science","url":"https://pubmed.ncbi.nlm.nih.gov/36889776","citation_count":4,"is_preprint":false},{"pmid":"38431645","id":"PMC_38431645","title":"The effects of restraint stress on ceramide metabolism disorders in the rat liver: the role of CerS6 in hepatocyte injury.","date":"2024","source":"Lipids in health and disease","url":"https://pubmed.ncbi.nlm.nih.gov/38431645","citation_count":3,"is_preprint":false},{"pmid":"39003397","id":"PMC_39003397","title":"Targeting CERS6-AS1/FGFR1 axis as synthetic vulnerability to constrain stromal cells supported proliferation in Mantle cell lymphoma.","date":"2024","source":"Leukemia","url":"https://pubmed.ncbi.nlm.nih.gov/39003397","citation_count":2,"is_preprint":false},{"pmid":"36444938","id":"PMC_36444938","title":"LncRNA CERS6-AS1, sponging miR-6838-5p, promotes proliferation and invasion in cervical carcinoma cells by upregulating FOXP2.","date":"2022","source":"Histology and histopathology","url":"https://pubmed.ncbi.nlm.nih.gov/36444938","citation_count":2,"is_preprint":false},{"pmid":"41203639","id":"PMC_41203639","title":"CERS6 promotes esophageal squamous cell carcinoma proliferation by increasing the stability of RPN1.","date":"2025","source":"Cell death discovery","url":"https://pubmed.ncbi.nlm.nih.gov/41203639","citation_count":1,"is_preprint":false},{"pmid":"41326554","id":"PMC_41326554","title":"Exploring the hub gene CERS6 as a therapeutic target in type 1 diabetes through a bioinformatics and network analyst approach.","date":"2025","source":"Scientific reports","url":"https://pubmed.ncbi.nlm.nih.gov/41326554","citation_count":0,"is_preprint":false},{"pmid":"41395279","id":"PMC_41395279","title":"Role and mechanism of the CBX4-HDAC5-CERS6 axis in disrupting sphingomyelin metabolism in acute myeloid leukemia.","date":"2025","source":"American journal of cancer research","url":"https://pubmed.ncbi.nlm.nih.gov/41395279","citation_count":0,"is_preprint":false},{"pmid":"41290121","id":"PMC_41290121","title":"LncRNA CERS6 - AS1 mediates the IGF2BP1/LIN28B axis to promote proliferation, migration and invasion in ovarian cancer.","date":"2025","source":"Biochimica et biophysica acta. Proteins and proteomics","url":"https://pubmed.ncbi.nlm.nih.gov/41290121","citation_count":0,"is_preprint":false},{"pmid":"37829519","id":"PMC_37829519","title":"Retracted: Effect and Mechanism of lncRNA CERS6-AS1 on the Biological Behavior of Prostate Cancer Cell.","date":"2023","source":"Applied bionics and biomechanics","url":"https://pubmed.ncbi.nlm.nih.gov/37829519","citation_count":0,"is_preprint":false},{"pmid":null,"id":"bio_10.1101_2025.05.19.652826","title":"E4BP4 Safeguards Brown Fat Mitochondria from Obesity-Induced Fragmentation via Ceramide Repression","date":"2025-05-19","source":"bioRxiv","url":"https://doi.org/10.1101/2025.05.19.652826","citation_count":0,"is_preprint":true},{"pmid":null,"id":"bio_10.1101_2024.08.23.609447","title":"BCL2L13 Influences Autophagy and Ceramide Metabolism without Affecting Temozolomide Resistance in Glioblastoma","date":"2024-08-26","source":"bioRxiv","url":"https://doi.org/10.1101/2024.08.23.609447","citation_count":0,"is_preprint":true}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":27176,"output_tokens":5540,"usd":0.082314},"stage2":{"model":"claude-opus-4-6","input_tokens":9096,"output_tokens":3291,"usd":0.191633},"total_usd":0.273947,"stage1_batch_id":"msgbatch_011kfMfE81o6CTcyhVUqumuW","stage2_batch_id":"msgbatch_01DTputS6WNkH745x1nVSoBo","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2005,\n      \"finding\": \"CERS6 (Lass6) encodes a ceramide synthase that preferentially synthesizes C14:0 and C16:0 ceramides from saturated/unsaturated fatty acyl-CoA substrates, with substrate preferences distinct from the closely related Lass5. The protein is N-glycosylated at its N-terminal Asn residue, indicating the N-terminus faces the luminal side of the ER membrane, while proteinase K digestion demonstrated the C-terminus faces the cytosolic side.\",\n      \"method\": \"Overexpression in cultured cells with ceramide species profiling, Northern blotting, glycosylation analysis, proteinase K digestion assay\",\n      \"journal\": \"The Biochemical journal\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 — multiple orthogonal biochemical methods in a single study establishing substrate specificity, glycosylation, and membrane topology\",\n      \"pmids\": [\"15823095\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"CerS6 specifically produces C16:0 ceramides in adipose tissue and liver; tissue-specific deletion of CerS6 in brown adipose tissue or liver in mice reduces C16:0 ceramides, increases energy expenditure, improves glucose tolerance, and protects from high-fat-diet-induced obesity, establishing CerS6-derived C16:0 ceramide as a mediator of obesity-associated insulin resistance.\",\n      \"method\": \"Conditional and global CerS6 knockout mice, ceramide species profiling by mass spectrometry, metabolic phenotyping (glucose/insulin tolerance tests, energy expenditure)\",\n      \"journal\": \"Cell metabolism\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — multiple tissue-specific KO models with rigorous metabolic phenotyping, replicated across BAT and liver compartments\",\n      \"pmids\": [\"25295788\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"CerS6 is a direct transcriptional target of p53; p53 binds within the CerS6 promoter region spanning 91 bp upstream to 60 bp downstream of the transcription start site at a non-canonical p53 response element, and non-genotoxic p53 activation (Nutlin-3 or low-dose actinomycin D) elevates CerS6 mRNA and protein, linking p53 to ceramide biosynthesis and pro-apoptotic response.\",\n      \"method\": \"Luciferase promoter assays, in vitro immunoprecipitation, electrophoretic mobility shift (gel shift) assay with purified p53, pharmacological p53 activation\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 — in vitro binding assays with purified protein plus promoter-reporter and mutagenesis of binding site\",\n      \"pmids\": [\"27302066\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"The lncRNA CERS6-AS1 binds to the RNA-binding protein IGF2BP3, and this interaction enhances the stability of CERS6 mRNA, thereby increasing CERS6 protein levels and promoting breast cancer progression.\",\n      \"method\": \"RNA pulldown, RIP assay, mRNA stability assays, rescue overexpression experiments in vitro and in vivo\",\n      \"journal\": \"Cancer medicine\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — reciprocal pulldown and RIP with functional rescue, single lab\",\n      \"pmids\": [\"31701672\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"Antisense oligonucleotide (ASO)-mediated knockdown of CerS6 in liver of obese mice reduces hepatic CerS6 mRNA by ~90% and C16:0 ceramides by ~50% in liver and plasma, and improves glucose tolerance and insulin sensitivity, confirming a causal role for CerS6-derived C16:0 ceramide in insulin resistance.\",\n      \"method\": \"ASO-mediated in vivo knockdown, ceramide profiling by mass spectrometry, glucose/insulin tolerance tests in ob/ob and HFD mouse models\",\n      \"journal\": \"Molecular metabolism\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — pharmacological target engagement with ceramide profiling and metabolic phenotyping in two independent disease models\",\n      \"pmids\": [\"30655217\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"CERS6 is required for lung cancer cell migration and invasion; CERS6 knockdown alters the ceramide profile, suppresses RAC1-positive lamellipodia/ruffling formation, and attenuates lung metastasis in mice, while forced CERS6 expression has the opposite effect. miR-101 negatively regulates CERS6 expression.\",\n      \"method\": \"siRNA knockdown, forced overexpression, ceramide profiling, RAC1 imaging, in vivo metastasis assay, luciferase promoter analysis\",\n      \"journal\": \"Journal of cellular and molecular medicine\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — bidirectional manipulation (KD and OE) with defined cellular phenotype (lamellipodia, metastasis) validated in vivo\",\n      \"pmids\": [\"32902157\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"AKT1 phosphorylates FOXP3 at Ser418, reducing FOXP3 binding to the CERS6 promoter and relieving repression of CERS6 transcription; the resulting excess C16:0 ceramide produced by CerS6 promotes accumulation of mutant p53 and pancreatic tumor growth.\",\n      \"method\": \"Co-immunoprecipitation, kinase assay (AKT1-FOXP3 phosphorylation), ChIP at CERS6 promoter, ceramide profiling, tumor xenograft\",\n      \"journal\": \"Cancer letters\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — CoIP and ChIP establish the AKT1/FOXP3/CERS6 axis, single lab\",\n      \"pmids\": [\"34343636\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"CEBPγ transcription factor binds the Y-box cis-element in the CERS6 promoter to activate CERS6 expression, and CEBPγ or YBX1 knockdown independently reduces CERS6 expression, ceramide-dependent lamellipodia formation, and cancer cell migration in NSCLC.\",\n      \"method\": \"Luciferase promoter analysis, siRNA knockdown, correlation analysis in 149 NSCLC patient datasets, cell migration assays\",\n      \"journal\": \"Cancer science\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — promoter analysis with functional knockdown showing cellular phenotype, single lab\",\n      \"pmids\": [\"33934437\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"CERS6 physically interacts with LASP1 (via LASP1's LIM domain), and both co-localize on lamellipodia in lung cancer cells. CERS6 and LASP1 each co-immunoprecipitate with actin, and these interactions are markedly reduced when the LASP1-CERS6 complex is disrupted. C16:0 ceramide partially rescues migration defects caused by silencing of either CERS6 or LASP1, indicating the LASP1-CERS6-actin ternary complex promotes cancer cell migration.\",\n      \"method\": \"Co-immunoprecipitation, LC-MS/MS interactome, co-localization imaging, siRNA knockdown, C16 ceramide rescue experiments\",\n      \"journal\": \"Cancers\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 — reciprocal CoIP confirmed by MS, localization, and functional rescue with defined lipid product\",\n      \"pmids\": [\"37345118\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"CerS6 deficiency in hypothalamic neurons (particularly POMC- and SF-1-expressing neurons) attenuates high-fat diet-induced weight gain, improves insulin sensitivity and glucose tolerance, prevents diet-induced mitochondrial morphology alterations, and improves leptin sensitivity, establishing CerS6-derived C16:0 ceramide as a mediator of hypothalamic lipotoxicity and ER/mitochondrial stress.\",\n      \"method\": \"Conditional (neuron-specific, POMC-Cre, SF-1-Cre) CerS6 knockout mice, metabolic phenotyping, mitochondrial morphology analysis, leptin sensitivity assays, in vitro palmitate treatment of hypothalamic neurons\",\n      \"journal\": \"Nature communications\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — multiple cell-type-specific KO models with defined metabolic and mitochondrial phenotypes\",\n      \"pmids\": [\"38016943\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"CERS6-derived ceramides (d18:1/14:0 and d18:1/16:0) inhibit PINK1-mediated mitophagy in renal tubular epithelial cells, possibly by binding to the PINK1 protein (supported by automated docking), leading to accumulation of damaged mitochondria and exacerbation of renal interstitial fibrosis in diabetic kidney disease. PINK1 inhibition in CERS6 knockdown cells diminished the protective effect.\",\n      \"method\": \"CerS6 knockout and knockdown in db/db mice and HK-2 cells, ceramide profiling by LC-MS/MS, mitophagy assays, molecular docking, PINK1 inhibition rescue experiment\",\n      \"journal\": \"American journal of physiology. Cell physiology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — in vivo KO with in vitro mechanistic follow-up; direct ceramide-PINK1 binding is computational only\",\n      \"pmids\": [\"37458434\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"CerS6-derived ceramide (d18:1/16:0) binds to the mitochondrial channel protein VDAC1 at Glu59, initiating mitochondrial DNA leakage and activating the cGAS-STING innate immune signaling pathway in podocytes, thereby promoting inflammatory responses in diabetic kidney disease.\",\n      \"method\": \"Podocyte-specific CerS6 knockout and overexpression mice, ceramide-VDAC1 binding analysis (with Glu59 site identified), mtDNA leakage assay, cGAS-STING pathway analysis\",\n      \"journal\": \"Nature communications\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 — bidirectional genetic manipulation (KO and OE) in vivo with defined molecular mechanism (ceramide-VDAC1 interaction at specific residue) and downstream pathway activation\",\n      \"pmids\": [\"39934147\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"High glucose promotes CerS6 synthesis through the TLR4/IKKβ signaling pathway; CerS6-derived C16:0 ceramide accumulates in mitochondria and promotes mitochondrial oxidative stress (mtROS), which triggers ferroptosis and liver cell injury. CerS6 knockdown attenuates mtROS and ferroptosis, while CerS6 overexpression exacerbates these effects, reversed by mitochondria-targeted antioxidant Mito-TEMPO.\",\n      \"method\": \"CerS6 knockout and overexpression in LO2 cells, TLR4/IKKβ pathway inhibition, mitochondrial ROS measurement, ferroptosis markers, Mito-TEMPO rescue\",\n      \"journal\": \"Molecular and cellular endocrinology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — bidirectional manipulation with pathway inhibition rescue, single lab\",\n      \"pmids\": [\"37230220\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"CerS6-derived C16:0 ceramide promotes lipid droplet biogenesis in hepatocytes during alcohol-associated liver disease; CerS6 deletion decreases PLIN2 (perilipin 2) protein expression in EtOH-fed mice and cells, and exogenous C16:0 ceramide treatment increases PLIN2 protein, establishing a CerS6/ceramide/PLIN2 axis in hepatic steatosis.\",\n      \"method\": \"CerS6 KO mice (both sexes) on ethanol diet, RNAseq, in vitro CerS6 deletion in VL17A hepatocytes, C16:0 ceramide treatment, PLIN2 protein analysis\",\n      \"journal\": \"Molecular metabolism\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — KO in vivo and in vitro with ceramide supplementation rescue, single lab\",\n      \"pmids\": [\"37714377\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"FTO (m6A demethylase) deficiency increases m6A modification on CERS6 mRNA, decreasing its stability and downregulating CerS6 expression in intestinal epithelial cells (IECs); this leads to accumulation of sphingosine-1-phosphate (S1P), which triggers proinflammatory macrophage activation and Th17 cell differentiation, exacerbating ulcerative colitis.\",\n      \"method\": \"Fto intestinal epithelial-specific knockout mice with DSS colitis, RNA and methylated RNA immunoprecipitation sequencing (RIP-seq), m6A profiling, conditioned medium macrophage experiments, LC-MS ceramide/S1P quantification\",\n      \"journal\": \"Gut\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — conditional KO with m6A sequencing and multiple downstream mechanistic validations in vivo and in vitro\",\n      \"pmids\": [\"37734910\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"CD36 regulates CerS6 protein stability; CD36 deficiency leads to accelerated CerS6 protein degradation, reduced C16:0 ceramide production, and attenuated LPS-induced inflammatory responses (MAPK, NF-κB, inflammasome activation). CerS6-derived C16:0 ceramide augments inflammatory responses through ER stress induction.\",\n      \"method\": \"CD36 knockout mice, CerS6 protein stability assay, LPS-induced inflammation in vitro and in vivo, cytokine measurement, inflammasome analysis\",\n      \"journal\": \"International immunopharmacology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — KO model with protein stability analysis and pathway characterization, single lab\",\n      \"pmids\": [\"39461238\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"Stress-induced corticosterone (CORT) activates the AMPK/p38 MAPK pathway to upregulate CerS6, increasing mitochondrial C16:0 ceramide; CerS6 knockdown in hepatocytes inhibits CORT-induced C16:0 ceramide elevation and mitochondrial cytochrome c release, while p38 MAPK inhibition (SB203580) attenuates CORT-induced CerS6 protein upregulation.\",\n      \"method\": \"Rat restraint stress model, CORT-treated hepatocytes, CerS6 knockdown, ceramide profiling by LC-MS/MS, mitochondrial isolation, cytochrome c release, kinase pathway inhibitor experiments\",\n      \"journal\": \"Lipids in health and disease\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — in vivo and in vitro models with pathway inhibitor rescue, single lab\",\n      \"pmids\": [\"38431645\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"Casein kinase 2α (CK2α) phosphorylates the C-terminal region of CerS6 to increase its enzymatic activity; the herbal compound DHG reduces CK2α protein expression and promotes CerS6 protein degradation (demonstrated by cycloheximide assay), thereby decreasing C16:0 ceramide in NASH.\",\n      \"method\": \"Cycloheximide protein stability assay in vitro, western blotting, CK2α expression analysis, ceramide profiling by HPLC-QQQ-MS/MS in rat NASH model\",\n      \"journal\": \"Journal of ethnopharmacology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 — CHX stability assay for degradation and CK2α-CerS6 phosphorylation relationship established, single lab\",\n      \"pmids\": [\"35654350\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"CBX4 indirectly activates CERS6 transcription by suppressing HDAC5 expression; HDAC5 directly targets the CERS6 promoter (confirmed by dual-luciferase reporter assay and ChIP), and CBX4 knockdown downregulates CERS6 mRNA and protein while activating PI3K/AKT and MAPK signaling in AML cells.\",\n      \"method\": \"siRNA knockdown, chromatin immunoprecipitation (ChIP), dual-luciferase reporter assay, RNA sequencing, proteomics, lipidomics in THP-1 and KG-1 AML cell lines\",\n      \"journal\": \"American journal of cancer research\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — ChIP and dual-luciferase reporter establish direct HDAC5-CERS6 promoter interaction, single lab\",\n      \"pmids\": [\"41395279\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"E4BP4 acts as a transcriptional repressor of Cers6 by binding to an enhancer region ~65 kb upstream of the Cers6 gene in brown adipose tissue, interacting with PRDM16 to suppress Cers6 mRNA expression and reduce C16:0 ceramide levels, thereby preventing obesity-induced mitochondrial fragmentation in BAT.\",\n      \"method\": \"E4BP4 gain-of-function in BAT, Cers6 mRNA quantification, C16:0 ceramide measurement, mitochondrial morphology analysis, E4BP4-PRDM16 interaction, enhancer binding assay\",\n      \"journal\": \"bioRxiv\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — preprint with gain-of-function and enhancer binding data, not yet peer-reviewed\",\n      \"pmids\": [\"bio_10.1101_2025.05.19.652826\"],\n      \"is_preprint\": true\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"CERS6 sustains the stability of ribophorin 1 (RPN1) by inhibiting its ubiquitination; this activates the RPN1-IRE1-XBP1 ER stress signaling pathway to reduce ER stress and ROS, promoting ESCC cell proliferation. This represents a ceramide-synthesis-independent function of CERS6.\",\n      \"method\": \"CERS6 overexpression and knockdown in ESCC cells and xenografts, ubiquitination assay for RPN1, ASO targeting of CERS6, IRE1-XBP1 pathway analysis\",\n      \"journal\": \"Cell death discovery\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — ubiquitination assay with bidirectional manipulation and pathway analysis, single lab, novel non-canonical function\",\n      \"pmids\": [\"41203639\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"CERS6 is an endoplasmic reticulum-resident ceramide synthase with a cytosol-facing C-terminus and lumen-facing N-terminus (N-glycosylated) that preferentially produces C14:0 and C16:0 ceramides from fatty acyl-CoA substrates; its transcription is directly activated by p53, CEBPγ, and the AKT1/FOXP3 axis, and repressed by E4BP4/PRDM16 and miR-101, while its protein stability is regulated by CD36 and CK2α-mediated phosphorylation; the resulting C16:0 ceramides drive metabolic dysfunction (obesity, insulin resistance, mitochondrial fragmentation, ER stress) by binding VDAC1 to trigger cGAS-STING inflammation and inhibiting PINK1-mediated mitophagy, and promote cancer cell migration through a LASP1-CERS6-actin ternary complex that drives RAC1-dependent lamellipodia formation.\"\n}\n```","stage2_raw":"```json\n{\n  \"mechanistic_narrative\": \"CERS6 is an endoplasmic reticulum-resident ceramide synthase that preferentially generates C14:0 and C16:0 ceramides and functions as a central node linking sphingolipid metabolism to energy homeostasis, inflammation, and cell migration. The enzyme is N-glycosylated at its luminal N-terminus and possesses a cytosol-facing C-terminus; its transcription is directly activated by p53 and CEBPγ and repressed by FOXP3 and HDAC5, while its mRNA stability is regulated by m6A modification and the lncRNA CERS6-AS1/IGF2BP3 axis, and its protein turnover is controlled by CD36 and CK2α-mediated phosphorylation [PMID:15823095, PMID:27302066, PMID:33934437, PMID:34343636, PMID:37734910, PMID:39461238, PMID:35654350, PMID:41395279]. CerS6-derived C16:0 ceramide drives obesity-associated insulin resistance and mitochondrial dysfunction across adipose, liver, and hypothalamic compartments, and triggers inflammatory signaling by binding VDAC1 at Glu59 to cause mitochondrial DNA leakage and cGAS–STING activation, or by inducing ER stress [PMID:25295788, PMID:38016943, PMID:39934147, PMID:37230220]. In cancer cells, CERS6 forms a ternary complex with LASP1 and actin at lamellipodia to promote RAC1-dependent migration and metastasis, and additionally stabilizes RPN1 to modulate ER stress through a ceramide-synthesis-independent mechanism [PMID:37345118, PMID:32902157, PMID:41203639].\",\n  \"teleology\": [\n    {\n      \"year\": 2005,\n      \"claim\": \"Identification of CERS6 as a ceramide synthase with C14:0/C16:0 acyl-CoA specificity and defined ER membrane topology resolved which enzyme produces these specific ceramide species and how it is oriented in the membrane.\",\n      \"evidence\": \"Overexpression with ceramide species profiling, glycosylation analysis, and proteinase K digestion in cultured cells\",\n      \"pmids\": [\"15823095\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"No crystal structure available\", \"Determinants of acyl-CoA selectivity not mapped to specific residues\", \"Regulation of enzymatic activity unknown at this stage\"]\n    },\n    {\n      \"year\": 2014,\n      \"claim\": \"Tissue-specific knockout of CerS6 in adipose and liver demonstrated that CerS6-derived C16:0 ceramide is causally required for diet-induced obesity and insulin resistance, establishing the enzyme as a metabolic disease driver rather than merely a biosynthetic enzyme.\",\n      \"evidence\": \"Conditional CerS6 knockout mice (BAT-Cre, liver-Cre) with metabolic phenotyping and ceramide mass spectrometry\",\n      \"pmids\": [\"25295788\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Downstream lipid effector mechanism (how C16:0 ceramide causes insulin resistance) not identified\", \"CNS contribution unknown\"]\n    },\n    {\n      \"year\": 2016,\n      \"claim\": \"Discovery that p53 directly binds a non-canonical response element in the CERS6 promoter connected tumor suppressor signaling to ceramide biosynthesis, providing a transcriptional mechanism for stress-induced ceramide elevation.\",\n      \"evidence\": \"Purified p53 gel-shift assay, luciferase promoter reporters with mutagenesis, pharmacological p53 activation\",\n      \"pmids\": [\"27302066\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Physiological relevance of p53-CERS6 axis in vivo not tested\", \"Other stress-responsive transcription factors not yet characterized\"]\n    },\n    {\n      \"year\": 2019,\n      \"claim\": \"ASO-mediated hepatic CerS6 knockdown replicated KO metabolic benefits in obese mice, validating CerS6 as a druggable therapeutic target for insulin resistance.\",\n      \"evidence\": \"ASO knockdown in ob/ob and HFD mouse models with ceramide profiling and metabolic tests\",\n      \"pmids\": [\"30655217\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Long-term safety and off-target sphingolipid effects not assessed\", \"Mechanism downstream of C16:0 ceramide reduction still undefined\"]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"CERS6 was shown to be required for RAC1-dependent lamellipodia formation and lung cancer metastasis, establishing a pro-migratory function beyond metabolic roles, with miR-101 identified as a negative regulator.\",\n      \"evidence\": \"Bidirectional manipulation (siRNA KD and overexpression) with RAC1 imaging and in vivo metastasis assay in lung cancer cells\",\n      \"pmids\": [\"32902157\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Whether migration depends on ceramide product or CERS6 protein scaffolding was unclear\", \"Direct miR-101 binding site not validated by mutagenesis\"]\n    },\n    {\n      \"year\": 2021,\n      \"claim\": \"Identification of additional transcriptional regulators (AKT1/FOXP3 axis and CEBPγ/YBX1) at the CERS6 promoter revealed that CERS6 is a convergence node for oncogenic kinase and transcription factor inputs in cancer.\",\n      \"evidence\": \"ChIP at CERS6 promoter for FOXP3, AKT1 kinase assay, luciferase reporter with CEBPγ binding, siRNA knockdown in NSCLC and pancreatic cancer lines\",\n      \"pmids\": [\"34343636\", \"33934437\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Combinatorial regulation by multiple factors not tested\", \"FOXP3 and CEBPγ studies each from single labs\", \"In vivo ChIP confirmation lacking for CEBPγ\"]\n    },\n    {\n      \"year\": 2022,\n      \"claim\": \"CK2α-mediated phosphorylation of CERS6's C-terminal region was shown to enhance its enzymatic activity and protein stability, providing the first post-translational regulatory mechanism for CERS6.\",\n      \"evidence\": \"Cycloheximide stability assay, CK2α expression analysis, ceramide profiling in NASH rat model\",\n      \"pmids\": [\"35654350\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Specific phosphorylation sites not mapped\", \"Direct in vitro kinase assay with purified proteins not performed\", \"Single lab, single disease model\"]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"The LASP1–CERS6–actin ternary complex was identified at lamellipodia, resolving that CERS6 has a scaffolding function in cell migration beyond ceramide production, with C16:0 ceramide partially rescuing migration when the complex is disrupted.\",\n      \"evidence\": \"Reciprocal co-IP confirmed by LC-MS/MS, co-localization imaging, siRNA with C16:0 ceramide rescue\",\n      \"pmids\": [\"37345118\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Structural basis of LASP1–CERS6 interaction beyond LIM domain requirement unknown\", \"Whether ceramide is produced locally at lamellipodia not demonstrated\"]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Multiple 2023 studies defined downstream effectors of CerS6-derived C16:0 ceramide in distinct tissues: binding VDAC1 at Glu59 to trigger mtDNA leakage and cGAS–STING inflammation in podocytes, inhibiting PINK1-mediated mitophagy in renal tubular cells, inducing mitochondrial ROS and ferroptosis in hepatocytes, and mediating hypothalamic lipotoxicity.\",\n      \"evidence\": \"Podocyte- and neuron-specific CerS6 KO mice, ceramide-VDAC1 binding analysis, mitophagy and ferroptosis assays, mitochondrial morphology analysis\",\n      \"pmids\": [\"39934147\", \"37458434\", \"37230220\", \"38016943\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Direct PINK1-ceramide binding is computational only (docking)\", \"Whether VDAC1 binding occurs in non-renal tissues not established\", \"Ferroptosis mechanism awaits genetic validation of ferroptosis markers\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"m6A modification was identified as a post-transcriptional control point for CERS6 mRNA stability, with FTO deficiency increasing m6A on CERS6 mRNA and reducing its expression; CD36 was separately shown to stabilize CerS6 protein, expanding the repertoire of CERS6 regulation to epitranscriptomic and membrane receptor-mediated mechanisms.\",\n      \"evidence\": \"FTO intestinal epithelial-specific KO with RIP-seq and m6A profiling; CD36 KO with protein stability assays\",\n      \"pmids\": [\"37734910\", \"39461238\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Specific m6A reader protein acting on CERS6 mRNA not identified\", \"Mechanism by which CD36 stabilizes CerS6 protein unknown\", \"Whether these regulatory modes operate in metabolic tissues beyond gut and macrophages unclear\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"A ceramide-synthesis-independent function of CERS6 was discovered: CERS6 stabilizes RPN1 by inhibiting its ubiquitination, activating IRE1–XBP1 ER stress signaling to promote ESCC cell proliferation, demonstrating that CERS6 has non-enzymatic roles.\",\n      \"evidence\": \"CERS6 overexpression/knockdown with ubiquitination assays for RPN1, ASO targeting, IRE1–XBP1 pathway analysis in ESCC cells and xenografts\",\n      \"pmids\": [\"41203639\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"The structural domain of CERS6 mediating RPN1 interaction is unmapped\", \"Whether this non-enzymatic function operates in non-cancer cells is unknown\", \"Single lab, not independently confirmed\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"Key unresolved questions include the structural basis of CERS6 acyl-CoA selectivity, whether the enzymatic and scaffolding functions are separable in vivo, whether C16:0 ceramide produced by CERS6 acts locally at specific organelle contact sites, and whether combinatorial transcriptional/post-translational inputs are integrated in physiological settings.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Low\",\n      \"gaps\": [\"No high-resolution structure of CERS6\", \"No separation-of-function mutant distinguishing catalytic and scaffolding roles\", \"Organelle-specific ceramide pools not resolved in vivo\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0016740\", \"supporting_discovery_ids\": [0, 1, 4]},\n      {\"term_id\": \"GO:0008289\", \"supporting_discovery_ids\": [0]},\n      {\"term_id\": \"GO:0098772\", \"supporting_discovery_ids\": [20]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005783\", \"supporting_discovery_ids\": [0]},\n      {\"term_id\": \"GO:0005886\", \"supporting_discovery_ids\": [8]},\n      {\"term_id\": \"GO:0005739\", \"supporting_discovery_ids\": [9, 11, 12]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-1430728\", \"supporting_discovery_ids\": [0, 1, 4, 9, 13]},\n      {\"term_id\": \"R-HSA-168256\", \"supporting_discovery_ids\": [11, 14, 15]},\n      {\"term_id\": \"R-HSA-5357801\", \"supporting_discovery_ids\": [10, 12]},\n      {\"term_id\": \"R-HSA-162582\", \"supporting_discovery_ids\": [6, 11, 16]},\n      {\"term_id\": \"R-HSA-8953897\", \"supporting_discovery_ids\": [9, 12, 15, 20]}\n    ],\n    \"complexes\": [\n      \"LASP1-CERS6-actin ternary complex\"\n    ],\n    \"partners\": [\n      \"LASP1\",\n      \"VDAC1\",\n      \"RPN1\",\n      \"CD36\",\n      \"FOXP3\",\n      \"IGF2BP3\",\n      \"CERS6-AS1\"\n    ],\n    \"other_free_text\": []\n  }\n}\n```"}