{"gene":"GSS","run_date":"2026-06-10T01:55:21","timeline":{"discoveries":[{"year":1999,"finding":"Nrf1 (CNC-bZIP transcription factor) regulates GSS gene expression; fibroblasts from Nrf1 knockout mice showed lower levels of glutathione and reduced GSS expression, indicating Nrf1 is required for transcriptional activation of GSS.","method":"Nrf1 knockout mouse fibroblasts; glutathione quantification; gene expression analysis","journal":"The Journal of biological chemistry","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — genetic loss-of-function with defined molecular phenotype (reduced GSS expression and glutathione), single lab but multiple readouts","pmids":["10601325"],"is_preprint":false},{"year":1995,"finding":"The human glutathione synthetase gene (GSS) maps to a single locus on chromosome 20q11.2, established by somatic cell hybrid analysis and in situ hybridization; Southern blot evidence indicates a single GSS gene in the human genome.","method":"Somatic cell hybrid analysis; in situ hybridization; Southern blot","journal":"Genomics","confidence":"High","confidence_rationale":"Tier 1-2 / Strong — two orthogonal mapping methods (somatic cell hybrids and in situ hybridization) independently confirming chromosomal location","pmids":["8825653"],"is_preprint":false},{"year":2003,"finding":"GSS splice mutations (not exonic mutations) account for glutathione synthetase deficiency in patients with undetectable GSS protein and severely decreased enzyme activity, as revealed by RT-PCR sequence analysis of mRNA.","method":"RT-PCR mRNA sequencing; enzyme activity assay in fibroblast lysates; polyclonal antibody-based immunodetection","journal":"Human mutation","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — direct enzyme activity measurement, protein immunodetection, and mRNA sequencing in patient-derived cells; single lab but three orthogonal methods","pmids":["14635114"],"is_preprint":false},{"year":2023,"finding":"GSS (glutathione synthetase) in pachytene spermatocytes is required for resistance to oxidative stress during spermatogenesis; germ cell-specific Gss knockout causes age-dependent male infertility via ferroptosis, with accumulation of ROS and lipid peroxidation. Young knockout mice are protected by compensatory GPX4 upregulation, which declines with age alongside ALOX15 increase, triggering ferroptosis; meiosis disruption and acrosome heterotopia result, and these defects are rescued by GSH or ferrostatin-1 (Fer-1) treatment.","method":"Conditional knockout mouse (Stra8-Cre); fertility assays; ROS and lipid peroxidation measurement; GPX4/ALOX15 protein quantification; GSH and Fer-1 rescue experiments; histology","journal":"Cell death & disease","confidence":"High","confidence_rationale":"Tier 2 / Strong — conditional KO with multiple orthogonal phenotypic readouts, mechanistic pathway placement (GSS→GSH→GPX4/ALOX15→ferroptosis), pharmacological rescue confirming mechanism","pmids":["38114454"],"is_preprint":false},{"year":2018,"finding":"Two novel compound heterozygous mutations in the GSS gene (c.738dupG in exon 8 causing frameshift p.S247fs, and a repetitive sequence insertion in exon 3) cause severe glutathione synthetase deficiency with markedly elevated urinary 5-oxoproline, confirming GSS as the causative gene for this phenotype.","method":"DNA sequence analysis; urine 5-oxoproline measurement; clinical biochemical assays","journal":"Brazilian journal of medical and biological research","confidence":"Low","confidence_rationale":"Tier 3 / Weak — genetic variant identification in single patient without functional reconstitution or enzyme activity data","pmids":["29340523"],"is_preprint":false},{"year":2024,"finding":"Two fetal siblings with compound heterozygous GSS variants (missense p.Arg267Gln and a 2.4 kb intragenic deletion causing out-of-frame exon 3 skipping) exhibited elevated amniotic 5-oxoproline consistent with disruption of the gamma-glutamyl cycle, and RNA-seq on brain tissue confirmed near-monoallelic expression with NMD-mediated degradation of the deletion allele.","method":"Genome sequencing; RNA-seq; amniotic fluid 5-oxoproline measurement; NMD analysis","journal":"Clinical genetics","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — RNA-seq and biochemical assay (5-oxoproline) provide functional evidence for variant pathogenicity; single case but orthogonal molecular and biochemical methods","pmids":["39221916"],"is_preprint":false},{"year":2026,"finding":"Age-related DNA methylation of the GSS promoter in bone marrow mesenchymal stem cells (BMSCs) suppresses GSS expression, limiting glutathione synthesis and impairing osteoblast differentiation independently of substrate (cysteine) availability; exosome-mediated GSH delivery to bone rescues osteogenic capacity, mitochondrial function, and reduces cellular senescence in aged bone.","method":"DNA methylation analysis; GSS promoter methylation; GSH synthesis flux assay; cysteine supplementation (negative control); CXCR4-exosome GSH delivery; in vivo bone formation assays","journal":"Bioactive materials","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — epigenetic mechanism (promoter methylation) identified with functional downstream consequences, negative substrate-supplementation control adds mechanistic specificity; single lab","pmids":["41674552"],"is_preprint":false},{"year":2025,"finding":"RRM2 directly regulates GSS expression; in hypertrophic scar fibroblasts, metformin downregulates RRM2, which suppresses GSS and thereby impairs glutathione synthesis, indirectly reducing GPX4 and triggering ferroptosis. This RRM2/GSS/GPX4 axis was validated in vitro and in a rabbit ear model.","method":"RRM2 knockdown/overexpression; GSS protein and mRNA quantification; GSH and GPX4 measurement; lipid peroxidation assays; in vivo rabbit ear hypertrophic scar model","journal":"Free radical biology & medicine","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — RRM2 manipulation with GSS as downstream readout, in vitro and in vivo orthogonal validation; single lab","pmids":["41619824"],"is_preprint":false},{"year":2025,"finding":"RRM2 directly regulates GSS to increase GSH synthesis in hepatocellular carcinoma cells; lncRNA HCG18 competitively binds miR-30a-5p to upregulate RRM2, which in turn elevates GSS expression and GSH levels, conferring ferroptosis resistance.","method":"Co-expression and ceRNA analysis; overexpression/knockdown of HCG18, miR-30a-5p, RRM2; GSS protein quantification; GSH measurement; colony formation and in vivo xenograft assays","journal":"International journal of biological sciences","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — RRM2→GSS→GSH pathway established by genetic manipulation with multiple readouts in vitro and in vivo; single lab","pmids":["40303288"],"is_preprint":false}],"current_model":"GSS (glutathione synthetase) catalyzes the final step of glutathione (GSH) biosynthesis; its transcription is regulated by Nrf1 and by promoter DNA methylation (in aging bone), while its expression is controlled upstream by RRM2; loss of GSS causes ferroptosis via ROS accumulation and lipid peroxidation (in spermatocytes and fibroblasts), and deficiency manifests clinically as 5-oxoprolinuria and hemolytic anemia due to impaired gamma-glutamyl cycle flux."},"narrative":{"mechanistic_narrative":"GSS encodes glutathione synthetase, the enzyme that supports glutathione (GSH) biosynthesis and thereby anchors cellular defense against oxidative stress; its loss diverts the gamma-glutamyl cycle toward 5-oxoproline accumulation and produces the clinical phenotype of glutathione synthetase deficiency [PMID:38114454, PMID:29340523]. In humans GSS resides at a single locus on chromosome 20q11.2, and compound heterozygous splice, frameshift, missense, and intragenic-deletion mutations abolish enzyme activity, eliminate detectable GSS protein, and elevate urinary or amniotic 5-oxoproline, establishing GSS as the causative gene for this disorder [PMID:8825653, PMID:14635114, PMID:29340523, PMID:39221916]. Because GSS output sustains GSH-dependent antioxidant capacity, its loss drives ferroptosis: in germ cell-specific knockout spermatocytes, depletion of GSH causes ROS and lipid peroxidation, with age-dependent failure of compensatory GPX4 and rising ALOX15 triggering ferroptotic male infertility that GSH or ferrostatin-1 rescues [PMID:38114454]. GSS expression is set transcriptionally by the CNC-bZIP factor Nrf1 and epigenetically by age-related promoter DNA methylation in bone marrow mesenchymal stem cells, which limits GSH synthesis independently of cysteine availability and impairs osteoblast differentiation [PMID:10601325, PMID:41674552]. Upstream, RRM2 directly regulates GSS to control GSH levels and ferroptosis sensitivity, an RRM2/GSS/GPX4 axis operative in hepatocellular carcinoma and hypertrophic scar fibroblasts [PMID:41619824, PMID:40303288].","teleology":[{"year":1995,"claim":"Defined the genomic basis of GSS by showing a single human gene at a fixed chromosomal location, establishing that one locus accounts for glutathione synthetase activity.","evidence":"Somatic cell hybrid analysis, in situ hybridization, and Southern blot mapping to 20q11.2","pmids":["8825653"],"confidence":"High","gaps":["Does not address enzyme mechanism or regulation","No functional assay of the gene product"]},{"year":1999,"claim":"Identified an upstream transcriptional control point, showing that GSS expression and cellular glutathione levels depend on the CNC-bZIP factor Nrf1.","evidence":"Glutathione quantification and gene expression analysis in Nrf1 knockout mouse fibroblasts","pmids":["10601325"],"confidence":"Medium","gaps":["Direct promoter binding by Nrf1 not demonstrated","Single lab; not confirmed in human cells"]},{"year":2003,"claim":"Resolved a molecular mechanism of disease by showing that splice (not exonic) mutations abolish GSS protein and enzyme activity in deficiency patients.","evidence":"RT-PCR mRNA sequencing, enzyme activity assay, and immunodetection in patient fibroblasts","pmids":["14635114"],"confidence":"Medium","gaps":["Limited mutation spectrum","No structural basis for activity loss"]},{"year":2018,"claim":"Extended the mutation spectrum, confirming novel frameshift and insertion alleles as causes of severe deficiency with 5-oxoprolinuria.","evidence":"DNA sequencing, urine 5-oxoproline, and clinical biochemistry in a patient","pmids":["29340523"],"confidence":"Low","gaps":["No functional reconstitution or enzyme activity data","Single patient"]},{"year":2023,"claim":"Placed GSS in a ferroptosis pathway in vivo, showing GSH output protects spermatocytes and that its loss causes age-dependent ferroptotic infertility.","evidence":"Germ cell-specific (Stra8-Cre) conditional knockout with ROS/lipid peroxidation, GPX4/ALOX15 quantification, and GSH/ferrostatin-1 rescue","pmids":["38114454"],"confidence":"High","gaps":["Mechanism of age-dependent GPX4 decline not defined","Relevance to human male infertility untested"]},{"year":2024,"claim":"Provided molecular evidence for variant pathogenicity by demonstrating NMD-mediated monoallelic expression and gamma-glutamyl cycle disruption in affected fetuses.","evidence":"Genome sequencing, RNA-seq, amniotic 5-oxoproline measurement, and NMD analysis","pmids":["39221916"],"confidence":"Medium","gaps":["Single family","No direct enzyme activity measurement"]},{"year":2025,"claim":"Identified RRM2 as a direct upstream regulator of GSS controlling GSH synthesis and ferroptosis resistance across cancer and fibrotic contexts.","evidence":"RRM2 knockdown/overexpression with GSS, GSH, GPX4, and lipid peroxidation readouts in vitro and in vivo (hepatocellular carcinoma xenograft and rabbit ear scar models); ceRNA HCG18/miR-30a-5p analysis","pmids":["41619824","40303288"],"confidence":"Medium","gaps":["Mechanism by which RRM2 regulates GSS transcription not defined","Single lab per context"]},{"year":2026,"claim":"Established an epigenetic control point, showing age-related GSS promoter methylation limits GSH synthesis and osteogenic capacity independent of substrate supply.","evidence":"Promoter methylation analysis, GSH flux assay with cysteine negative control, and CXCR4-exosome GSH delivery in aged bone in vivo","pmids":["41674552"],"confidence":"Medium","gaps":["Methyltransferase responsible not identified","Single lab"]},{"year":null,"claim":"How GSS transcriptional, epigenetic, and RRM2-dependent regulatory inputs are integrated, and the structural basis of enzyme activity loss in disease mutants, remain unresolved.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No structural model of human GSS or its mutants in the corpus","Direct promoter occupancy by Nrf1 and RRM2-GSS regulatory mechanism undefined","Human disease ferroptosis link not directly tested"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0016874","term_label":"ligase activity","supporting_discovery_ids":[2]},{"term_id":"GO:0016740","term_label":"transferase activity","supporting_discovery_ids":[3]}],"localization":[],"pathway":[{"term_id":"R-HSA-1430728","term_label":"Metabolism","supporting_discovery_ids":[3,5]},{"term_id":"R-HSA-5357801","term_label":"Programmed Cell Death","supporting_discovery_ids":[3,7]}],"complexes":[],"partners":[],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"P48637","full_name":"Glutathione synthetase","aliases":["Glutathione synthase"],"length_aa":474,"mass_kda":52.4,"function":"Catalyzes the production of glutathione from gamma-glutamylcysteine and glycine in an ATP-dependent manner (PubMed:7646467, PubMed:9215686). Glutathione (gamma-glutamylcysteinylglycine, GSH) is the most abundant intracellular thiol in living aerobic cells and is required for numerous processes including the protection of cells against oxidative damage, amino acid transport, the detoxification of foreign compounds, the maintenance of protein sulfhydryl groups in a reduced state and acts as a cofactor for a number of enzymes (PubMed:10369661). Participates in ophthalmate biosynthesis in hepatocytes (By similarity)","subcellular_location":"","url":"https://www.uniprot.org/uniprotkb/P48637/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/GSS","classification":"Not Classified","n_dependent_lines":22,"n_total_lines":1208,"dependency_fraction":0.018211920529801324},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[],"url":"https://opencell.sf.czbiohub.org/search/GSS","total_profiled":1310},"omim":[{"mim_id":"614243","title":"5-@OXOPROLINASE (ATP-HYDROLYZING); OPLAH","url":"https://www.omim.org/entry/614243"},{"mim_id":"612342","title":"GAMMA-GLUTAMYLTRANSFERASE 7; GGT7","url":"https://www.omim.org/entry/612342"},{"mim_id":"603863","title":"RING FINGER PROTEIN 7; RNF7","url":"https://www.omim.org/entry/603863"},{"mim_id":"601002","title":"GLUTATHIONE SYNTHETASE; GSS","url":"https://www.omim.org/entry/601002"},{"mim_id":"266130","title":"GLUTATHIONE SYNTHETASE DEFICIENCY; GSSD","url":"https://www.omim.org/entry/266130"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Supported","locations":[{"location":"Nucleoplasm","reliability":"Supported"}],"tissue_specificity":"Low tissue specificity","tissue_distribution":"Detected in all","driving_tissues":[],"url":"https://www.proteinatlas.org/search/GSS"},"hgnc":{"alias_symbol":[],"prev_symbol":[]},"alphafold":{"accession":"P48637","domains":[{"cath_id":"-","chopping":"5-336_401-472","consensus_level":"medium","plddt":95.379,"start":5,"end":472},{"cath_id":"3.30.1490.50","chopping":"337-400","consensus_level":"medium","plddt":93.8878,"start":337,"end":400}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/P48637","model_url":"https://alphafold.ebi.ac.uk/files/AF-P48637-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-P48637-F1-predicted_aligned_error_v6.png","plddt_mean":94.94},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=GSS","jax_strain_url":"https://www.jax.org/strain/search?query=GSS"},"sequence":{"accession":"P48637","fasta_url":"https://rest.uniprot.org/uniprotkb/P48637.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/P48637/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/P48637"}},"corpus_meta":[{"pmid":"10601325","id":"PMC_10601325","title":"The CNC basic leucine zipper factor, Nrf1, is essential for cell survival in response to oxidative stress-inducing agents. Role for Nrf1 in gamma-gcs(l) and gss expression in mouse fibroblasts.","date":"1999","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/10601325","citation_count":156,"is_preprint":false},{"pmid":"15962001","id":"PMC_15962001","title":"Immunodetection of disease-associated mutant PrP, which accelerates disease in GSS transgenic mice.","date":"2005","source":"The EMBO journal","url":"https://pubmed.ncbi.nlm.nih.gov/15962001","citation_count":124,"is_preprint":false},{"pmid":"10656806","id":"PMC_10656806","title":"A synthetic peptide initiates Gerstmann-Sträussler-Scheinker (GSS) disease in transgenic mice.","date":"2000","source":"Journal of molecular biology","url":"https://pubmed.ncbi.nlm.nih.gov/10656806","citation_count":115,"is_preprint":false},{"pmid":"22043907","id":"PMC_22043907","title":"Upregulation of micro RNA-146a (miRNA-146a), a marker for inflammatory neurodegeneration, in sporadic Creutzfeldt-Jakob disease (sCJD) and Gerstmann-Straussler-Scheinker (GSS) syndrome.","date":"2011","source":"Journal of toxicology and environmental health. Part A","url":"https://pubmed.ncbi.nlm.nih.gov/22043907","citation_count":88,"is_preprint":false},{"pmid":"33746607","id":"PMC_33746607","title":"Ammonium Ferric Citrate induced Ferroptosis in Non-Small-Cell Lung Carcinoma through the inhibition of GPX4-GSS/GSR-GGT axis activity.","date":"2021","source":"International journal of medical sciences","url":"https://pubmed.ncbi.nlm.nih.gov/33746607","citation_count":58,"is_preprint":false},{"pmid":"18038270","id":"PMC_18038270","title":"Human tau protein forms complex with PrP and some GSS- and fCJD-related PrP mutants possess stronger binding activities with tau in vitro.","date":"2007","source":"Molecular and cellular biochemistry","url":"https://pubmed.ncbi.nlm.nih.gov/18038270","citation_count":57,"is_preprint":false},{"pmid":"38114454","id":"PMC_38114454","title":"Gss deficiency causes age-related fertility impairment via ROS-triggered ferroptosis in the testes of mice.","date":"2023","source":"Cell death & disease","url":"https://pubmed.ncbi.nlm.nih.gov/38114454","citation_count":42,"is_preprint":false},{"pmid":"12814912","id":"PMC_12814912","title":"Channels formed with a mutant prion protein PrP(82-146) homologous to a 7-kDa fragment in diseased brain of GSS patients.","date":"2003","source":"American journal of physiology. Cell physiology","url":"https://pubmed.ncbi.nlm.nih.gov/12814912","citation_count":42,"is_preprint":false},{"pmid":"31783581","id":"PMC_31783581","title":"Targeting FAT1 Inhibits Carcinogenesis, Induces Oxidative Stress and Enhances Cisplatin Sensitivity through Deregulation of LRP5/WNT2/GSS Signaling Axis in Oral Squamous Cell Carcinoma.","date":"2019","source":"Cancers","url":"https://pubmed.ncbi.nlm.nih.gov/31783581","citation_count":35,"is_preprint":false},{"pmid":"35398749","id":"PMC_35398749","title":"Regulatory mechanism of α-hederin upon cisplatin sensibility in NSCLC at safe dose by destroying GSS/GSH/GPX2 axis-mediated glutathione oxidation-reduction system.","date":"2022","source":"Biomedicine & pharmacotherapy = Biomedecine & pharmacotherapie","url":"https://pubmed.ncbi.nlm.nih.gov/35398749","citation_count":34,"is_preprint":false},{"pmid":"20547632","id":"PMC_20547632","title":"The first case of protease-sensitive prionopathy (PSPr) in The Netherlands: a patient with an unusual GSS-like clinical phenotype.","date":"2010","source":"Journal of neurology, neurosurgery, and psychiatry","url":"https://pubmed.ncbi.nlm.nih.gov/20547632","citation_count":34,"is_preprint":false},{"pmid":"28934494","id":"PMC_28934494","title":"Derivatives of Bst-like Gss-polymerase with improved processivity and inhibitor tolerance.","date":"2017","source":"Nucleic acids research","url":"https://pubmed.ncbi.nlm.nih.gov/28934494","citation_count":33,"is_preprint":false},{"pmid":"1684758","id":"PMC_1684758","title":"The transmissible amyloidoses: genetical control of spontaneous generation of infectious amyloid proteins by nucleation of configurational change in host precursors: kuru-CJD-GSS-scrapie-BSE.","date":"1991","source":"European journal of epidemiology","url":"https://pubmed.ncbi.nlm.nih.gov/1684758","citation_count":32,"is_preprint":false},{"pmid":"26135918","id":"PMC_26135918","title":"Transmission Properties of Human PrP 102L Prions Challenge the Relevance of Mouse Models of GSS.","date":"2015","source":"PLoS pathogens","url":"https://pubmed.ncbi.nlm.nih.gov/26135918","citation_count":25,"is_preprint":false},{"pmid":"8825653","id":"PMC_8825653","title":"The gene encoding human glutathione synthetase (GSS) maps to the long arm of chromosome 20 at band 11.2.","date":"1995","source":"Genomics","url":"https://pubmed.ncbi.nlm.nih.gov/8825653","citation_count":24,"is_preprint":false},{"pmid":"17368456","id":"PMC_17368456","title":"Preliminary study on the receptor of gonad-stimulating substance (GSS) as a gonadotropin of starfish.","date":"2007","source":"General and comparative endocrinology","url":"https://pubmed.ncbi.nlm.nih.gov/17368456","citation_count":23,"is_preprint":false},{"pmid":"22965875","id":"PMC_22965875","title":"Substitutions at residue 211 in the prion protein drive a switch between CJD and GSS syndrome, a new mechanism governing inherited neurodegenerative disorders.","date":"2012","source":"Human molecular genetics","url":"https://pubmed.ncbi.nlm.nih.gov/22965875","citation_count":22,"is_preprint":false},{"pmid":"29338055","id":"PMC_29338055","title":"A novel Gerstmann-Sträussler-Scheinker disease mutation defines a precursor for amyloidogenic 8 kDa PrP fragments and reveals N-terminal structural changes shared by other GSS alleles.","date":"2018","source":"PLoS pathogens","url":"https://pubmed.ncbi.nlm.nih.gov/29338055","citation_count":21,"is_preprint":false},{"pmid":"23299511","id":"PMC_23299511","title":"Identification of miRNA encoded by Jatropha curcas from EST and GSS.","date":"2013","source":"Plant signaling & behavior","url":"https://pubmed.ncbi.nlm.nih.gov/23299511","citation_count":20,"is_preprint":false},{"pmid":"22134181","id":"PMC_22134181","title":"Participation of Gs-proteins in the action of relaxin-like gonad-stimulating substance (GSS) for 1-methyladenine production in starfish ovarian follicle cells.","date":"2011","source":"General and comparative endocrinology","url":"https://pubmed.ncbi.nlm.nih.gov/22134181","citation_count":18,"is_preprint":false},{"pmid":"14635114","id":"PMC_14635114","title":"Diagnostics in patients with glutathione synthetase deficiency but without mutations in the exons of the GSS gene.","date":"2003","source":"Human mutation","url":"https://pubmed.ncbi.nlm.nih.gov/14635114","citation_count":17,"is_preprint":false},{"pmid":"32516343","id":"PMC_32516343","title":"Spontaneous generation of prions and transmissible PrP amyloid in a humanised transgenic mouse model of A117V GSS.","date":"2020","source":"PLoS biology","url":"https://pubmed.ncbi.nlm.nih.gov/32516343","citation_count":17,"is_preprint":false},{"pmid":"32082076","id":"PMC_32082076","title":"Suppressive Effects of GSS on Lipopolysaccharide-Induced Endothelial Cell Injury and ALI via TNF-α and IL-6.","date":"2019","source":"Mediators of inflammation","url":"https://pubmed.ncbi.nlm.nih.gov/32082076","citation_count":16,"is_preprint":false},{"pmid":"20829230","id":"PMC_20829230","title":"A Drosophila model of GSS syndrome suggests defects in active zones are responsible for pathogenesis of GSS syndrome.","date":"2010","source":"Human molecular genetics","url":"https://pubmed.ncbi.nlm.nih.gov/20829230","citation_count":16,"is_preprint":false},{"pmid":"21295575","id":"PMC_21295575","title":"Hormonal action of relaxin-like gonad-stimulating substance (GSS) on starfish ovaries in growing and fully grown states.","date":"2011","source":"General and comparative endocrinology","url":"https://pubmed.ncbi.nlm.nih.gov/21295575","citation_count":16,"is_preprint":false},{"pmid":"29340523","id":"PMC_29340523","title":"A case of severe glutathione synthetase deficiency with novel GSS mutations.","date":"2018","source":"Brazilian journal of medical and biological research = Revista brasileira de pesquisas medicas e biologicas","url":"https://pubmed.ncbi.nlm.nih.gov/29340523","citation_count":13,"is_preprint":false},{"pmid":"18782453","id":"PMC_18782453","title":"ReRep: computational detection of repetitive sequences in genome survey sequences (GSS).","date":"2008","source":"BMC bioinformatics","url":"https://pubmed.ncbi.nlm.nih.gov/18782453","citation_count":12,"is_preprint":false},{"pmid":"7607672","id":"PMC_7607672","title":"High-resolution physical mapping of a 250-kb region of human chromosome 11q24 by genomic sequence sampling (GSS).","date":"1995","source":"Genomics","url":"https://pubmed.ncbi.nlm.nih.gov/7607672","citation_count":11,"is_preprint":false},{"pmid":"21214405","id":"PMC_21214405","title":"Autophagy contributes to widespread neuronal degeneration in hamsters infected with the Echigo-1 strain of Creutzfeldt-Jakob disease and mice infected with the Fujisaki strain of Gerstmann-Sträussler-Scheinker (GSS) syndrome.","date":"2011","source":"Ultrastructural pathology","url":"https://pubmed.ncbi.nlm.nih.gov/21214405","citation_count":11,"is_preprint":false},{"pmid":"1687809","id":"PMC_1687809","title":"[Recent advances in the research of Creutzfeldt-Jakob disease (CJD) and Gerstmann-Strüssler syndrome (GSS)].","date":"1991","source":"Rinsho shinkeigaku = Clinical neurology","url":"https://pubmed.ncbi.nlm.nih.gov/1687809","citation_count":10,"is_preprint":false},{"pmid":"23054223","id":"PMC_23054223","title":"Characterization of HMW-GSs and their gene inaction in tetraploid wheat.","date":"2012","source":"Genetica","url":"https://pubmed.ncbi.nlm.nih.gov/23054223","citation_count":9,"is_preprint":false},{"pmid":"40303288","id":"PMC_40303288","title":"Targeting HCG18 counteracts ferroptosis resistance via blocking the miR-30a-5p/RRM2/GSS pathway in hepatocellular carcinoma.","date":"2025","source":"International journal of biological sciences","url":"https://pubmed.ncbi.nlm.nih.gov/40303288","citation_count":8,"is_preprint":false},{"pmid":"31189938","id":"PMC_31189938","title":"\"Dual Disease\" TgAD/GSS mice exhibit enhanced Alzheimer's disease pathology and reveal PrPC-dependent secretion of Aβ.","date":"2019","source":"Scientific reports","url":"https://pubmed.ncbi.nlm.nih.gov/31189938","citation_count":8,"is_preprint":false},{"pmid":"11771163","id":"PMC_11771163","title":"[A case of Gerstmann-Sträussler-Scheinker syndrome (GSS) with late onset--a haplotype analysis of Glu219Lys polymorphism in PrP gene].","date":"2001","source":"Rinsho shinkeigaku = Clinical neurology","url":"https://pubmed.ncbi.nlm.nih.gov/11771163","citation_count":7,"is_preprint":false},{"pmid":"36397183","id":"PMC_36397183","title":"Effects of HMW-GSs at Glu-B1 locus on starch-protein interaction and starch digestibility during thermomechanical processing of wheat dough.","date":"2022","source":"Journal of the science of food and agriculture","url":"https://pubmed.ncbi.nlm.nih.gov/36397183","citation_count":6,"is_preprint":false},{"pmid":"31890235","id":"PMC_31890235","title":"A case of Gerstmann-Straussler-Scheinker (GSS) disease with supranuclear gaze palsy.","date":"2019","source":"Journal of clinical movement disorders","url":"https://pubmed.ncbi.nlm.nih.gov/31890235","citation_count":6,"is_preprint":false},{"pmid":"32256010","id":"PMC_32256010","title":"Analysis of microRNAs and their targets from onion (Allium cepa) using genome survey sequences (GSS) and expressed sequence tags (ESTs).","date":"2019","source":"Bioinformation","url":"https://pubmed.ncbi.nlm.nih.gov/32256010","citation_count":6,"is_preprint":false},{"pmid":"27999069","id":"PMC_27999069","title":"Genotypic susceptibility score (GSS) and CD4+ T cell recovery in HIV-1 patients with suppressed viral load.","date":"2016","source":"The Journal of antimicrobial chemotherapy","url":"https://pubmed.ncbi.nlm.nih.gov/27999069","citation_count":5,"is_preprint":false},{"pmid":"38754351","id":"PMC_38754351","title":"Dynamic behaviors of protein and water associated with fresh noodle quality during processing based on different HMW-GSs at Glu-D1.","date":"2024","source":"Food chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/38754351","citation_count":4,"is_preprint":false},{"pmid":"37281473","id":"PMC_37281473","title":"Absence of 1-Methyladenine Production in Follicle Cells Obtained from Starfish Ovaries in the Post-Spawning Season: (starfish follicle celis/1-MeAde/GSS/cAMP/post-spawning season).","date":"1991","source":"Development, growth & differentiation","url":"https://pubmed.ncbi.nlm.nih.gov/37281473","citation_count":4,"is_preprint":false},{"pmid":"38193206","id":"PMC_38193206","title":"HMW-GSs 1Dx3+1Dy12 contribute to a suitable wheat gluten strength that confers superior Chinese steamed bread quality.","date":"2024","source":"Journal of food science","url":"https://pubmed.ncbi.nlm.nih.gov/38193206","citation_count":3,"is_preprint":false},{"pmid":"25397488","id":"PMC_25397488","title":"Improved therapy-success prediction with GSS estimated from clinical HIV-1 sequences.","date":"2014","source":"Journal of the International AIDS Society","url":"https://pubmed.ncbi.nlm.nih.gov/25397488","citation_count":3,"is_preprint":false},{"pmid":"18409537","id":"PMC_18409537","title":"[Case of Gerstmann-Sträussler-Scheinker syndrome (GSS-P102L) mimicking variant Creurtzfeldt-Jakob disease in clinical manifestation and MRI findings].","date":"2008","source":"Rinsho shinkeigaku = Clinical neurology","url":"https://pubmed.ncbi.nlm.nih.gov/18409537","citation_count":3,"is_preprint":false},{"pmid":"16768100","id":"PMC_16768100","title":"[Patient with Gerstmann-Striussler-Scheinker syndrome (GSS P102L) presenting high intensity lesions in the cerebral cortex on diffusion weighted MRI].","date":"2006","source":"Rinsho shinkeigaku = Clinical neurology","url":"https://pubmed.ncbi.nlm.nih.gov/16768100","citation_count":3,"is_preprint":false},{"pmid":"37281076","id":"PMC_37281076","title":"Effect of Ca2+ -free Seawater Treatment on 1-Methyladenine Production in Starfish Ovarian Follicle Cells: (starfish follicle cells/1-MeAde/GSS/cAMP/Ca2 +-free seawater).","date":"1994","source":"Development, growth & differentiation","url":"https://pubmed.ncbi.nlm.nih.gov/37281076","citation_count":2,"is_preprint":false},{"pmid":"21997095","id":"PMC_21997095","title":"Design studies for ASIC implementations of 28 GS/s optical QPSK- and 16-QAM-OFDM transceivers.","date":"2011","source":"Optics express","url":"https://pubmed.ncbi.nlm.nih.gov/21997095","citation_count":2,"is_preprint":false},{"pmid":"41674552","id":"PMC_41674552","title":"Age-related GSS promoter methylation in BMSCs drives osteoporosis and the reversal by targeted GSH delivery.","date":"2026","source":"Bioactive materials","url":"https://pubmed.ncbi.nlm.nih.gov/41674552","citation_count":1,"is_preprint":false},{"pmid":"22211659","id":"PMC_22211659","title":"Does GSS still maintain relevance on HAART outcome after the introduction of newest active antiretroviral drugs? 48 weeks results.","date":"2011","source":"Current HIV research","url":"https://pubmed.ncbi.nlm.nih.gov/22211659","citation_count":1,"is_preprint":false},{"pmid":"21364775","id":"PMC_21364775","title":"Insights from the GC content analysis of 76genome survey sequences (GSS) from Elaeisoleifera.","date":"2010","source":"Bioinformation","url":"https://pubmed.ncbi.nlm.nih.gov/21364775","citation_count":1,"is_preprint":false},{"pmid":"9103904","id":"PMC_9103904","title":"[Creutzfeldt-Jakob disease(CJD) and Gerstmann-Sträussler-Scheinker syndrome(GSS)].","date":"1997","source":"Nihon rinsho. Japanese journal of clinical medicine","url":"https://pubmed.ncbi.nlm.nih.gov/9103904","citation_count":0,"is_preprint":false},{"pmid":"39221916","id":"PMC_39221916","title":"Multiple congenital anomalies in two fetuses with glutathione-synthetase deficit (GSS).","date":"2024","source":"Clinical genetics","url":"https://pubmed.ncbi.nlm.nih.gov/39221916","citation_count":0,"is_preprint":false},{"pmid":"41619824","id":"PMC_41619824","title":"Metformin targets RRM2/GSS/GPX4 axis to induce fibroblast ferroptosis: A foreground strategy against hypertrophic scarring.","date":"2026","source":"Free radical biology & medicine","url":"https://pubmed.ncbi.nlm.nih.gov/41619824","citation_count":0,"is_preprint":false},{"pmid":null,"id":"bio_10.1101_2025.11.18.689143","title":"Impact of Cell Size, Light Wavelengths, and Intensities on Growth, Oxygen Production, and Consumption Rates of  <i>Chromochloris zofingiensis</i>  and  <i>Haematococcus lacustris</i>","date":"2025-11-20","source":"bioRxiv","url":"https://doi.org/10.1101/2025.11.18.689143","citation_count":0,"is_preprint":true},{"pmid":null,"id":"bio_10.1101_2025.07.14.664451","title":"Beyond Threat: Changes in Visuocortical Engagement and Oscillatory Brain Activity during Non-Aversive Associative Learning","date":"2025-07-18","source":"bioRxiv","url":"https://doi.org/10.1101/2025.07.14.664451","citation_count":0,"is_preprint":true},{"pmid":null,"id":"bio_10.1101_2025.03.30.646185","title":"Mosquito Sex Separation using Complementation of Selectable Traits and Engineered Neo-Sex Chromosomes","date":"2025-03-31","source":"bioRxiv","url":"https://doi.org/10.1101/2025.03.30.646185","citation_count":0,"is_preprint":true},{"pmid":null,"id":"bio_10.1101_2025.07.27.667006","title":"A high-quality bread wheat genome unravels adaptive evolution of wheat end-use quality","date":"2025-07-27","source":"bioRxiv","url":"https://doi.org/10.1101/2025.07.27.667006","citation_count":0,"is_preprint":true},{"pmid":null,"id":"bio_10.1101_2025.01.21.25320913","title":"VR-based Gamma Sensory Stimulation: A feasibility study","date":"2025-01-23","source":"bioRxiv","url":"https://doi.org/10.1101/2025.01.21.25320913","citation_count":0,"is_preprint":true},{"pmid":null,"id":"bio_10.1101_2025.04.22.650062","title":"CRISPR/Cas9-mediated mutagenesis of the  <i>white-eye</i>  gene in the tephritid pest  <i>Bactrocera zonata</i>","date":"2025-04-23","source":"bioRxiv","url":"https://doi.org/10.1101/2025.04.22.650062","citation_count":0,"is_preprint":true},{"pmid":null,"id":"bio_10.1101_2025.03.31.25324988","title":"An Analysis of household catastrophic health expenditure and food insecurity in Ghana","date":"2025-04-01","source":"bioRxiv","url":"https://doi.org/10.1101/2025.03.31.25324988","citation_count":0,"is_preprint":true}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":30234,"output_tokens":2268,"usd":0.062361,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":9452,"output_tokens":2649,"usd":0.056743,"stage2_stop_reason":"end_turn"},"total_usd":0.119104,"stage1_batch_id":"msgbatch_01DUPACZi7AAWwuZiUjseQF4","stage2_batch_id":"msgbatch_018yt7chE3f48PEFtDwtj6AE","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 1999,\n      \"finding\": \"Nrf1 (CNC-bZIP transcription factor) regulates GSS gene expression; fibroblasts from Nrf1 knockout mice showed lower levels of glutathione and reduced GSS expression, indicating Nrf1 is required for transcriptional activation of GSS.\",\n      \"method\": \"Nrf1 knockout mouse fibroblasts; glutathione quantification; gene expression analysis\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genetic loss-of-function with defined molecular phenotype (reduced GSS expression and glutathione), single lab but multiple readouts\",\n      \"pmids\": [\"10601325\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1995,\n      \"finding\": \"The human glutathione synthetase gene (GSS) maps to a single locus on chromosome 20q11.2, established by somatic cell hybrid analysis and in situ hybridization; Southern blot evidence indicates a single GSS gene in the human genome.\",\n      \"method\": \"Somatic cell hybrid analysis; in situ hybridization; Southern blot\",\n      \"journal\": \"Genomics\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 / Strong — two orthogonal mapping methods (somatic cell hybrids and in situ hybridization) independently confirming chromosomal location\",\n      \"pmids\": [\"8825653\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2003,\n      \"finding\": \"GSS splice mutations (not exonic mutations) account for glutathione synthetase deficiency in patients with undetectable GSS protein and severely decreased enzyme activity, as revealed by RT-PCR sequence analysis of mRNA.\",\n      \"method\": \"RT-PCR mRNA sequencing; enzyme activity assay in fibroblast lysates; polyclonal antibody-based immunodetection\",\n      \"journal\": \"Human mutation\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — direct enzyme activity measurement, protein immunodetection, and mRNA sequencing in patient-derived cells; single lab but three orthogonal methods\",\n      \"pmids\": [\"14635114\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"GSS (glutathione synthetase) in pachytene spermatocytes is required for resistance to oxidative stress during spermatogenesis; germ cell-specific Gss knockout causes age-dependent male infertility via ferroptosis, with accumulation of ROS and lipid peroxidation. Young knockout mice are protected by compensatory GPX4 upregulation, which declines with age alongside ALOX15 increase, triggering ferroptosis; meiosis disruption and acrosome heterotopia result, and these defects are rescued by GSH or ferrostatin-1 (Fer-1) treatment.\",\n      \"method\": \"Conditional knockout mouse (Stra8-Cre); fertility assays; ROS and lipid peroxidation measurement; GPX4/ALOX15 protein quantification; GSH and Fer-1 rescue experiments; histology\",\n      \"journal\": \"Cell death & disease\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — conditional KO with multiple orthogonal phenotypic readouts, mechanistic pathway placement (GSS→GSH→GPX4/ALOX15→ferroptosis), pharmacological rescue confirming mechanism\",\n      \"pmids\": [\"38114454\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"Two novel compound heterozygous mutations in the GSS gene (c.738dupG in exon 8 causing frameshift p.S247fs, and a repetitive sequence insertion in exon 3) cause severe glutathione synthetase deficiency with markedly elevated urinary 5-oxoproline, confirming GSS as the causative gene for this phenotype.\",\n      \"method\": \"DNA sequence analysis; urine 5-oxoproline measurement; clinical biochemical assays\",\n      \"journal\": \"Brazilian journal of medical and biological research\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — genetic variant identification in single patient without functional reconstitution or enzyme activity data\",\n      \"pmids\": [\"29340523\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"Two fetal siblings with compound heterozygous GSS variants (missense p.Arg267Gln and a 2.4 kb intragenic deletion causing out-of-frame exon 3 skipping) exhibited elevated amniotic 5-oxoproline consistent with disruption of the gamma-glutamyl cycle, and RNA-seq on brain tissue confirmed near-monoallelic expression with NMD-mediated degradation of the deletion allele.\",\n      \"method\": \"Genome sequencing; RNA-seq; amniotic fluid 5-oxoproline measurement; NMD analysis\",\n      \"journal\": \"Clinical genetics\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — RNA-seq and biochemical assay (5-oxoproline) provide functional evidence for variant pathogenicity; single case but orthogonal molecular and biochemical methods\",\n      \"pmids\": [\"39221916\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2026,\n      \"finding\": \"Age-related DNA methylation of the GSS promoter in bone marrow mesenchymal stem cells (BMSCs) suppresses GSS expression, limiting glutathione synthesis and impairing osteoblast differentiation independently of substrate (cysteine) availability; exosome-mediated GSH delivery to bone rescues osteogenic capacity, mitochondrial function, and reduces cellular senescence in aged bone.\",\n      \"method\": \"DNA methylation analysis; GSS promoter methylation; GSH synthesis flux assay; cysteine supplementation (negative control); CXCR4-exosome GSH delivery; in vivo bone formation assays\",\n      \"journal\": \"Bioactive materials\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — epigenetic mechanism (promoter methylation) identified with functional downstream consequences, negative substrate-supplementation control adds mechanistic specificity; single lab\",\n      \"pmids\": [\"41674552\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"RRM2 directly regulates GSS expression; in hypertrophic scar fibroblasts, metformin downregulates RRM2, which suppresses GSS and thereby impairs glutathione synthesis, indirectly reducing GPX4 and triggering ferroptosis. This RRM2/GSS/GPX4 axis was validated in vitro and in a rabbit ear model.\",\n      \"method\": \"RRM2 knockdown/overexpression; GSS protein and mRNA quantification; GSH and GPX4 measurement; lipid peroxidation assays; in vivo rabbit ear hypertrophic scar model\",\n      \"journal\": \"Free radical biology & medicine\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — RRM2 manipulation with GSS as downstream readout, in vitro and in vivo orthogonal validation; single lab\",\n      \"pmids\": [\"41619824\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"RRM2 directly regulates GSS to increase GSH synthesis in hepatocellular carcinoma cells; lncRNA HCG18 competitively binds miR-30a-5p to upregulate RRM2, which in turn elevates GSS expression and GSH levels, conferring ferroptosis resistance.\",\n      \"method\": \"Co-expression and ceRNA analysis; overexpression/knockdown of HCG18, miR-30a-5p, RRM2; GSS protein quantification; GSH measurement; colony formation and in vivo xenograft assays\",\n      \"journal\": \"International journal of biological sciences\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — RRM2→GSS→GSH pathway established by genetic manipulation with multiple readouts in vitro and in vivo; single lab\",\n      \"pmids\": [\"40303288\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"GSS (glutathione synthetase) catalyzes the final step of glutathione (GSH) biosynthesis; its transcription is regulated by Nrf1 and by promoter DNA methylation (in aging bone), while its expression is controlled upstream by RRM2; loss of GSS causes ferroptosis via ROS accumulation and lipid peroxidation (in spermatocytes and fibroblasts), and deficiency manifests clinically as 5-oxoprolinuria and hemolytic anemia due to impaired gamma-glutamyl cycle flux.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"GSS encodes glutathione synthetase, the enzyme that supports glutathione (GSH) biosynthesis and thereby anchors cellular defense against oxidative stress; its loss diverts the gamma-glutamyl cycle toward 5-oxoproline accumulation and produces the clinical phenotype of glutathione synthetase deficiency [#3, #4]. In humans GSS resides at a single locus on chromosome 20q11.2, and compound heterozygous splice, frameshift, missense, and intragenic-deletion mutations abolish enzyme activity, eliminate detectable GSS protein, and elevate urinary or amniotic 5-oxoproline, establishing GSS as the causative gene for this disorder [#1, #2, #4, #5]. Because GSS output sustains GSH-dependent antioxidant capacity, its loss drives ferroptosis: in germ cell-specific knockout spermatocytes, depletion of GSH causes ROS and lipid peroxidation, with age-dependent failure of compensatory GPX4 and rising ALOX15 triggering ferroptotic male infertility that GSH or ferrostatin-1 rescues [#3]. GSS expression is set transcriptionally by the CNC-bZIP factor Nrf1 and epigenetically by age-related promoter DNA methylation in bone marrow mesenchymal stem cells, which limits GSH synthesis independently of cysteine availability and impairs osteoblast differentiation [#0, #6]. Upstream, RRM2 directly regulates GSS to control GSH levels and ferroptosis sensitivity, an RRM2/GSS/GPX4 axis operative in hepatocellular carcinoma and hypertrophic scar fibroblasts [#7, #8].\",\n  \"teleology\": [\n    {\n      \"year\": 1995,\n      \"claim\": \"Defined the genomic basis of GSS by showing a single human gene at a fixed chromosomal location, establishing that one locus accounts for glutathione synthetase activity.\",\n      \"evidence\": \"Somatic cell hybrid analysis, in situ hybridization, and Southern blot mapping to 20q11.2\",\n      \"pmids\": [\"8825653\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Does not address enzyme mechanism or regulation\", \"No functional assay of the gene product\"]\n    },\n    {\n      \"year\": 1999,\n      \"claim\": \"Identified an upstream transcriptional control point, showing that GSS expression and cellular glutathione levels depend on the CNC-bZIP factor Nrf1.\",\n      \"evidence\": \"Glutathione quantification and gene expression analysis in Nrf1 knockout mouse fibroblasts\",\n      \"pmids\": [\"10601325\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct promoter binding by Nrf1 not demonstrated\", \"Single lab; not confirmed in human cells\"]\n    },\n    {\n      \"year\": 2003,\n      \"claim\": \"Resolved a molecular mechanism of disease by showing that splice (not exonic) mutations abolish GSS protein and enzyme activity in deficiency patients.\",\n      \"evidence\": \"RT-PCR mRNA sequencing, enzyme activity assay, and immunodetection in patient fibroblasts\",\n      \"pmids\": [\"14635114\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Limited mutation spectrum\", \"No structural basis for activity loss\"]\n    },\n    {\n      \"year\": 2018,\n      \"claim\": \"Extended the mutation spectrum, confirming novel frameshift and insertion alleles as causes of severe deficiency with 5-oxoprolinuria.\",\n      \"evidence\": \"DNA sequencing, urine 5-oxoproline, and clinical biochemistry in a patient\",\n      \"pmids\": [\"29340523\"],\n      \"confidence\": \"Low\",\n      \"gaps\": [\"No functional reconstitution or enzyme activity data\", \"Single patient\"]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Placed GSS in a ferroptosis pathway in vivo, showing GSH output protects spermatocytes and that its loss causes age-dependent ferroptotic infertility.\",\n      \"evidence\": \"Germ cell-specific (Stra8-Cre) conditional knockout with ROS/lipid peroxidation, GPX4/ALOX15 quantification, and GSH/ferrostatin-1 rescue\",\n      \"pmids\": [\"38114454\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Mechanism of age-dependent GPX4 decline not defined\", \"Relevance to human male infertility untested\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Provided molecular evidence for variant pathogenicity by demonstrating NMD-mediated monoallelic expression and gamma-glutamyl cycle disruption in affected fetuses.\",\n      \"evidence\": \"Genome sequencing, RNA-seq, amniotic 5-oxoproline measurement, and NMD analysis\",\n      \"pmids\": [\"39221916\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Single family\", \"No direct enzyme activity measurement\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Identified RRM2 as a direct upstream regulator of GSS controlling GSH synthesis and ferroptosis resistance across cancer and fibrotic contexts.\",\n      \"evidence\": \"RRM2 knockdown/overexpression with GSS, GSH, GPX4, and lipid peroxidation readouts in vitro and in vivo (hepatocellular carcinoma xenograft and rabbit ear scar models); ceRNA HCG18/miR-30a-5p analysis\",\n      \"pmids\": [\"41619824\", \"40303288\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Mechanism by which RRM2 regulates GSS transcription not defined\", \"Single lab per context\"]\n    },\n    {\n      \"year\": 2026,\n      \"claim\": \"Established an epigenetic control point, showing age-related GSS promoter methylation limits GSH synthesis and osteogenic capacity independent of substrate supply.\",\n      \"evidence\": \"Promoter methylation analysis, GSH flux assay with cysteine negative control, and CXCR4-exosome GSH delivery in aged bone in vivo\",\n      \"pmids\": [\"41674552\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Methyltransferase responsible not identified\", \"Single lab\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How GSS transcriptional, epigenetic, and RRM2-dependent regulatory inputs are integrated, and the structural basis of enzyme activity loss in disease mutants, remain unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No structural model of human GSS or its mutants in the corpus\", \"Direct promoter occupancy by Nrf1 and RRM2-GSS regulatory mechanism undefined\", \"Human disease ferroptosis link not directly tested\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0016874\", \"supporting_discovery_ids\": [2]},\n      {\"term_id\": \"GO:0016740\", \"supporting_discovery_ids\": [3]}\n    ],\n    \"localization\": [],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-1430728\", \"supporting_discovery_ids\": [3, 5]},\n      {\"term_id\": \"R-HSA-5357801\", \"supporting_discovery_ids\": [3, 7]}\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}}