{"gene":"ADD1","run_date":"2026-04-28T17:12:37","timeline":{"discoveries":[{"year":1993,"finding":"ADD1 is a novel basic helix-loop-helix leucine zipper transcription factor that binds sequence-specifically to an E-box motif in the fatty acid synthase gene promoter and activates transcription in a differentiation-dependent manner in adipocytes.","method":"Oligonucleotide screening of adipocyte cDNA library, CAT reporter assays, sequence-specific DNA binding","journal":"Molecular and cellular biology","confidence":"High","confidence_rationale":"Tier 1 — original discovery with DNA binding and transcriptional activation assays, foundational paper with 512 citations","pmids":["8336713"],"is_preprint":false},{"year":1995,"finding":"ADD1/SREBP1 has dual DNA sequence specificity, binding both E-box (ATCACGTGA) and SRE-1 (ATCACCCCAC) motifs; this dual specificity is controlled by a single atypical tyrosine residue in the basic region — substituting it with arginine restricts binding to E-box only, while introducing tyrosine into USF confers dual specificity.","method":"PCR-amplified binding analysis, site-directed mutagenesis, promoter-reporter (CAT) transcriptional assays","journal":"Molecular and cellular biology","confidence":"High","confidence_rationale":"Tier 1 — mutagenesis with functional validation, 294 citations, multiple orthogonal methods","pmids":["7739539"],"is_preprint":false},{"year":1998,"finding":"ADD1/SREBP1 activates PPARγ specifically through its ligand-binding domain by stimulating production and secretion of endogenous lipid ligand(s) that directly bind PPARγ and displace radiolabeled thiazolidinedione.","method":"Gal4-LBD fusion reporter assays, conditioned medium transfer experiments, radioligand displacement binding assay","journal":"Proceedings of the National Academy of Sciences of the United States of America","confidence":"High","confidence_rationale":"Tier 1 — multiple orthogonal methods including direct ligand binding assay; 555 citations","pmids":["9539737"],"is_preprint":false},{"year":1999,"finding":"Id2 and Id3 proteins physically interact with ADD1/SREBP1c and inhibit its DNA binding to the fatty acid synthase promoter, thereby repressing ADD1/SREBP1c-dependent transcription in adipocytes.","method":"Gel mobility-shift assays (EMSA), co-immunoprecipitation of in vitro-translated proteins, CAT reporter assays in adipocytes","journal":"The Biochemical journal","confidence":"High","confidence_rationale":"Tier 1-2 — reciprocal co-IP plus EMSA plus functional reporter assays","pmids":["10585876"],"is_preprint":false},{"year":2003,"finding":"Twist2 (Dermo-1) physically interacts with the N-terminal domain of ADD1/SREBP1c, reduces its binding to target DNA sequences, and represses its transcriptional activity; this repression is partly dependent on HDAC activity.","method":"Yeast two-hybrid screen with adipocyte cDNA library, co-immunoprecipitation, luciferase reporter assays, HDAC inhibitor treatment","journal":"Nucleic acids research","confidence":"High","confidence_rationale":"Tier 2 — yeast two-hybrid confirmed by co-IP, functional rescue with HDAC inhibitors, multiple orthogonal methods","pmids":["14654692"],"is_preprint":false},{"year":2004,"finding":"GSK3β phosphorylates ADD1/SREBP1c in vitro and in vivo and negatively regulates its transcriptional activity; GSK3 inhibition enhances ADD1/SREBP1c target gene expression (FAS, ACC1, SCD1) without requiring de novo protein synthesis, indicating regulation at the post-translational level.","method":"In vitro kinase assay, in vivo phosphorylation assay, GSK3 inhibitor treatment, overexpression of GSK3β, luciferase reporter assays, cycloheximide chase","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 1 — in vitro kinase assay plus in vivo phosphorylation plus functional reporters with multiple controls","pmids":["15466874"],"is_preprint":false},{"year":2005,"finding":"ADD1/SREBP1c directly regulates mouse 6-phosphogluconate dehydrogenase (6PGDH) gene expression by binding an E-box motif in its promoter; insulin-dependent 6PGDH induction is mediated through ADD1/SREBP1c via the PI3-kinase pathway.","method":"DNase I footprinting assay, point mutation analysis, reporter assays, PI3-kinase inhibitor treatment","journal":"Biochemical and biophysical research communications","confidence":"Medium","confidence_rationale":"Tier 1 — footprinting and mutagenesis with functional reporters, single lab","pmids":["15896329"],"is_preprint":false},{"year":2009,"finding":"ADD1/SREBP1c directly induces PGC1α expression by binding a conserved E-box in the proximal PGC1α promoter; β-adrenergic stimulation recruits ADD1/SREBP1c to this E-box in brown adipocytes.","method":"Luciferase reporter assays, chromatin immunoprecipitation (ChIP), adrenergic receptor agonist treatment","journal":"Biochimica et biophysica acta","confidence":"Medium","confidence_rationale":"Tier 2 — ChIP plus reporter assays, single lab","pmids":["19962449"],"is_preprint":false},{"year":2012,"finding":"In C. elegans, α-adducin (add-1) is required for consolidation of synaptic plasticity and sustained synaptic increase of AMPA-type glutamate receptor (GLR-1) content through its actin-capping activity in a splice-form- and tissue-specific manner; human ADD1 expression in nematodes fully rescues loss of C. elegans add-1 function.","method":"Loss-of-function genetics, live imaging of GLR-1 turnover, aversive olfactory associative learning assays, human ADD1 rescue in C. elegans","journal":"The EMBO journal","confidence":"High","confidence_rationale":"Tier 2 — multiple orthogonal methods (genetics, live imaging, cross-species rescue), functional conservation validated","pmids":["22307086"],"is_preprint":false},{"year":2012,"finding":"Add1 knockout mice develop strain-dependent hyperkyphosis, megaesophagus, and reduced axon numbers in peripheral nerves, revealing non-erythroid functions for α-adducin in neural and skeletal tissue.","method":"Targeted gene deletion (knockout mice), histological and morphological analysis, peripheral nerve axon counting","journal":"Genesis (New York, N.Y. : 2000)","confidence":"Medium","confidence_rationale":"Tier 2 — clean KO with defined non-erythroid phenotypic readouts, single lab","pmids":["22926980"],"is_preprint":false},{"year":2021,"finding":"Loss-of-function ADD1 variants in humans cause corpus callosum dysgenesis, ventriculomegaly, and intellectual disability; ADD1 is required for dimerization with ADD2, and Add1 knockout mice recapitulate corpus callosum dysgenesis and ventriculomegaly.","method":"Exome sequencing, RNA sequencing, super-resolution imaging, immunoblotting, ADD1-ADD2 dimerization assay, Add1 knockout mouse phenotyping","journal":"Genetics in medicine : official journal of the American College of Medical Genetics","confidence":"High","confidence_rationale":"Tier 2 — human genetics validated by mouse KO and molecular dimerization assays, multiple orthogonal methods","pmids":["34906466"],"is_preprint":false},{"year":2023,"finding":"S-nitrosylation of cathepsin B promotes dephosphorylation and nuclear translocation of ADD1, which then recruits MATR3 and ADAR1 to CTSB mRNA, driving A-to-I RNA editing and increased CTSB mRNA stability via HuR binding.","method":"S-nitrosylation assay, subcellular fractionation/nuclear translocation assay, co-immunoprecipitation (ADD1-MATR3-ADAR1 complex), RNA editing sequencing, HuR binding assay, mRNA stability assay","journal":"Cell research","confidence":"High","confidence_rationale":"Tier 1-2 — multiple orthogonal biochemical methods establishing a novel regulatory axis, published in high-impact journal","pmids":["37156877"],"is_preprint":false},{"year":2023,"finding":"ADD1/SREBP1c binds E-box elements in the CHRDL1 gene upstream region and activates its transcription; TWIST2 competes with ADD1/SREBP1c for binding to the same DNA site and blocks ADD1/SREBP1c-mediated activation.","method":"EMSA, luciferase reporter assays, EMSA competition assays","journal":"Genes","confidence":"Medium","confidence_rationale":"Tier 1-2 — EMSA and reporter assays demonstrate direct competition, single lab","pmids":["37761873"],"is_preprint":false},{"year":2024,"finding":"ADD1 (and other adducins) regulate the proliferation capacity and fate of basal neural progenitors during neocortical neurogenesis; ADD1 knockout in human cortical organoids reduces progenitor proliferation and causes aberrant neurogenesis, while adducin overexpression increases progenitor protrusions and proliferative capacity.","method":"In vivo mouse and ferret neocortex overexpression, ADD1 knockout in human cortical organoids, immunohistochemistry, progenitor counting","journal":"bioRxiv","confidence":"Medium","confidence_rationale":"Tier 2 — KO in organoids plus in vivo gain-of-function in multiple species, but preprint not yet peer-reviewed","pmids":["bio_10.1101_2024.11.08.622634"],"is_preprint":true}],"current_model":"ADD1 (adducin α-subunit / SREBP1c) functions as a basic HLH-leucine zipper transcription factor that activates lipogenic and adipogenic gene expression by binding E-box and SRE-1 motifs (dual specificity controlled by a single tyrosine in the basic region), activates PPARγ by producing endogenous lipid ligands, is negatively regulated post-translationally by GSK3β-mediated phosphorylation and by interacting repressors (Id2/3, Twist2), drives PGC1α expression in brown adipocytes, and—in its role as an actin-capping cytoskeletal protein—controls synaptic AMPA receptor trafficking for memory consolidation, nuclear translocation to recruit the MATR3/ADAR1 RNA-editing complex upon S-nitrosylation signaling, and neural progenitor proliferation and fate during neocortical development."},"narrative":{"teleology":[{"year":1993,"claim":"The identification of ADD1 as a bHLH-LZ transcription factor that binds the fatty acid synthase E-box and activates transcription in adipocytes established the gene's primary molecular identity as a lipogenic transcriptional regulator.","evidence":"Oligonucleotide screening of adipocyte cDNA library with CAT reporter assays and DNA-binding analysis","pmids":["8336713"],"confidence":"High","gaps":["Mechanism of differentiation-dependent activation not resolved","Relationship to SREBP family not yet established"]},{"year":1995,"claim":"Demonstrating that a single tyrosine in the basic region confers dual E-box/SRE-1 DNA-binding specificity resolved how one transcription factor can regulate both cholesterol and fatty acid pathway promoters.","evidence":"Site-directed mutagenesis with PCR-amplified binding analysis and CAT reporter assays","pmids":["7739539"],"confidence":"High","gaps":["Structural basis for tyrosine-mediated dual recognition not determined at atomic resolution","In vivo significance of dual specificity not tested"]},{"year":1998,"claim":"Showing that ADD1/SREBP1c activates PPARγ by producing a secreted endogenous lipid ligand that displaces thiazolidinedione revealed a feed-forward lipogenic circuit linking SREBP1c to nuclear receptor activation.","evidence":"Gal4-LBD fusion reporter assays, conditioned-medium transfer, and radioligand displacement binding assay","pmids":["9539737"],"confidence":"High","gaps":["Chemical identity of the endogenous PPARγ ligand not determined","Physiological relevance in intact adipose tissue not shown"]},{"year":1999,"claim":"Identification of Id2/Id3 as physical interactors that inhibit ADD1/SREBP1c DNA binding established a dominant-negative regulatory mechanism for lipogenic transcription.","evidence":"EMSA, co-immunoprecipitation of in vitro-translated proteins, and CAT reporter assays in adipocytes","pmids":["10585876"],"confidence":"High","gaps":["In vivo relevance of Id-mediated repression in lipid metabolism not tested","Stoichiometry of Id–SREBP1c complexes unknown"]},{"year":2003,"claim":"Twist2 was found to repress ADD1/SREBP1c by physical interaction and reduced DNA binding in an HDAC-dependent manner, revealing a second class of bHLH-mediated transcriptional repression targeting lipogenesis.","evidence":"Yeast two-hybrid screen, co-immunoprecipitation, luciferase reporters, and HDAC inhibitor rescue","pmids":["14654692"],"confidence":"High","gaps":["Which specific HDACs are recruited to the Twist2–SREBP1c complex is unknown","Physiological context for Twist2–SREBP1c antagonism not defined in vivo"]},{"year":2004,"claim":"Demonstrating that GSK3β phosphorylates ADD1/SREBP1c and suppresses its transcriptional activity post-translationally identified an insulin-responsive kinase switch controlling lipogenic gene expression.","evidence":"In vitro and in vivo kinase assays, GSK3 inhibitor treatment, luciferase reporters, cycloheximide chase","pmids":["15466874"],"confidence":"High","gaps":["Specific phosphorylation sites mapped by GSK3β on SREBP1c not fully characterized","Interplay between GSK3β phosphorylation and proteasomal degradation not resolved"]},{"year":2009,"claim":"ChIP evidence that β-adrenergic stimulation recruits ADD1/SREBP1c to a conserved E-box in the PGC1α promoter connected lipogenic transcription factor activity to thermogenic gene regulation in brown adipocytes.","evidence":"Chromatin immunoprecipitation and luciferase reporter assays in brown adipocytes treated with adrenergic agonist","pmids":["19962449"],"confidence":"Medium","gaps":["Whether ADD1/SREBP1c is necessary for cold-induced PGC1α expression in vivo is untested","Mechanism linking β-adrenergic signaling to SREBP1c chromatin recruitment not elucidated"]},{"year":2012,"claim":"Cross-species genetic studies established that α-adducin's actin-capping activity is required for synaptic AMPA receptor retention and memory consolidation, separating its cytoskeletal function from its transcription factor role.","evidence":"C. elegans loss-of-function genetics, live GLR-1 imaging, olfactory learning assays, and human ADD1 rescue","pmids":["22307086"],"confidence":"High","gaps":["Mechanism by which actin-capping stabilizes AMPA receptors at postsynaptic sites not defined","Whether mammalian synaptic plasticity uses the same splice-form dependence is unknown"]},{"year":2012,"claim":"Add1 knockout mice displaying hyperkyphosis, megaesophagus, and reduced peripheral nerve axon numbers revealed non-erythroid developmental roles for α-adducin.","evidence":"Targeted gene deletion in mice with histological and morphological analysis","pmids":["22926980"],"confidence":"Medium","gaps":["Strain dependence of phenotypes not mechanistically explained","Cell-autonomous versus non-autonomous roles of ADD1 in these tissues not distinguished"]},{"year":2021,"claim":"Human genetic evidence that loss-of-function ADD1 variants cause corpus callosum dysgenesis and intellectual disability, recapitulated in knockout mice, established ADD1 as a Mendelian disease gene for neurodevelopmental malformation.","evidence":"Exome sequencing in affected families, super-resolution imaging, ADD1-ADD2 dimerization assay, Add1 knockout mouse phenotyping","pmids":["34906466"],"confidence":"High","gaps":["How disrupted ADD1–ADD2 dimerization leads to corpus callosum dysgenesis at the cellular level is unknown","Whether heterozygous carriers show intermediate phenotypes is not addressed"]},{"year":2023,"claim":"Discovery that dephosphorylated ADD1 translocates to the nucleus and recruits a MATR3/ADAR1 complex for A-to-I RNA editing of CTSB mRNA revealed an unexpected nuclear function for the cytoskeletal protein in RNA processing.","evidence":"S-nitrosylation assay, subcellular fractionation, co-immunoprecipitation of ADD1–MATR3–ADAR1, RNA editing sequencing, mRNA stability assay","pmids":["37156877"],"confidence":"High","gaps":["Whether ADD1 recruits MATR3/ADAR1 to other mRNA targets beyond CTSB is unknown","Signal that triggers ADD1 dephosphorylation downstream of S-nitrosylation not fully delineated"]},{"year":null,"claim":"It remains unresolved how the cytoskeletal and transcriptional functions of ADD1 are coordinated in the same cell, whether ADD1-dependent RNA editing extends to a broad set of transcripts, and what the structural basis is for the ADD1–ADD2 dimer in neurodevelopment.","evidence":"","pmids":[],"confidence":"Low","gaps":["No structural model for the ADD1–ADD2 heterodimer","Genome-wide identification of ADD1-dependent RNA editing targets not performed","Integration of cytoskeletal versus transcriptional versus RNA-editing functions in a unified signaling framework is lacking"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0003677","term_label":"DNA binding","supporting_discovery_ids":[0,1,6,7,12]},{"term_id":"GO:0140110","term_label":"transcription regulator activity","supporting_discovery_ids":[0,1,2,5,6,7,12]},{"term_id":"GO:0008092","term_label":"cytoskeletal protein binding","supporting_discovery_ids":[8]},{"term_id":"GO:0003723","term_label":"RNA binding","supporting_discovery_ids":[11]}],"localization":[{"term_id":"GO:0005634","term_label":"nucleus","supporting_discovery_ids":[0,1,7,11]},{"term_id":"GO:0005829","term_label":"cytosol","supporting_discovery_ids":[8,11]}],"pathway":[{"term_id":"R-HSA-74160","term_label":"Gene expression (Transcription)","supporting_discovery_ids":[0,1,5,6,7,12]},{"term_id":"R-HSA-1430728","term_label":"Metabolism","supporting_discovery_ids":[0,2,5,6]},{"term_id":"R-HSA-1266738","term_label":"Developmental Biology","supporting_discovery_ids":[10,9]},{"term_id":"R-HSA-112316","term_label":"Neuronal System","supporting_discovery_ids":[8,10]},{"term_id":"R-HSA-8953854","term_label":"Metabolism of RNA","supporting_discovery_ids":[11]}],"complexes":["ADD1-ADD2 heterodimer","ADD1-MATR3-ADAR1 nuclear RNA-editing complex"],"partners":["ADD2","MATR3","ADAR1","ID2","ID3","TWIST2","GSK3B"],"other_free_text":[]},"mechanistic_narrative":"ADD1 encodes α-adducin, a multifunctional protein that operates both as a cytoskeletal actin-capping protein regulating membrane-cytoskeleton interactions and, through its SREBP1c isoform, as a basic helix-loop-helix-leucine zipper transcription factor controlling lipogenic and adipogenic gene expression. As a transcription factor (ADD1/SREBP1c), it binds both E-box and SRE-1 DNA motifs—a dual specificity governed by a single atypical tyrosine in its basic region—to activate fatty acid synthase, 6-phosphogluconate dehydrogenase, PGC1α, and CHRDL1, and it stimulates PPARγ activity by producing endogenous lipid ligands; its transcriptional output is negatively regulated by GSK3β-mediated phosphorylation and by inhibitory interactions with Id2/Id3 and Twist2 [PMID:7739539, PMID:9539737, PMID:15466874, PMID:10585876, PMID:14654692]. In its cytoskeletal capacity, ADD1's actin-capping activity is required for consolidation of synaptic AMPA receptor content and associative memory, and upon S-nitrosylation signaling it translocates to the nucleus where it recruits a MATR3/ADAR1 complex to drive A-to-I RNA editing of cathepsin B mRNA [PMID:22307086, PMID:37156877]. Loss-of-function ADD1 variants in humans cause corpus callosum dysgenesis, ventriculomegaly, and intellectual disability, phenotypes recapitulated in Add1 knockout mice [PMID:34906466]."},"prefetch_data":{"uniprot":{"accession":"P35611","full_name":"Alpha-adducin","aliases":["Erythrocyte adducin subunit alpha"],"length_aa":737,"mass_kda":81.0,"function":"Membrane-cytoskeleton-associated protein that promotes the assembly of the spectrin-actin network. Binds to calmodulin","subcellular_location":"Cytoplasm, cytoskeleton; Cell membrane","url":"https://www.uniprot.org/uniprotkb/P35611/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/ADD1","classification":"Not Classified","n_dependent_lines":1,"n_total_lines":1208,"dependency_fraction":0.0008278145695364238},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[{"gene":"ACTB","stoichiometry":0.2},{"gene":"ACTG1","stoichiometry":0.2}],"url":"https://opencell.sf.czbiohub.org/search/ADD1","total_profiled":1310},"omim":[{"mim_id":"617008","title":"CEREBRAL PALSY, SPASTIC QUADRIPLEGIC, 3; CPSQ3","url":"https://www.omim.org/entry/617008"},{"mim_id":"613004","title":"HUNTINGTIN; HTT","url":"https://www.omim.org/entry/613004"},{"mim_id":"601568","title":"ADDUCIN 3; ADD3","url":"https://www.omim.org/entry/601568"},{"mim_id":"601510","title":"SREBP CLEAVAGE-ACTIVATING PROTEIN; SCAP","url":"https://www.omim.org/entry/601510"},{"mim_id":"145500","title":"HYPERTENSION, ESSENTIAL","url":"https://www.omim.org/entry/145500"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Enhanced","locations":[{"location":"Plasma membrane","reliability":"Enhanced"},{"location":"Nucleoplasm","reliability":"Additional"}],"tissue_specificity":"Low tissue specificity","tissue_distribution":"Detected in all","driving_tissues":[],"url":"https://www.proteinatlas.org/search/ADD1"},"hgnc":{"alias_symbol":[],"prev_symbol":[]},"alphafold":{"accession":"P35611","domains":[{"cath_id":"3.40.225.10","chopping":"134-336","consensus_level":"high","plddt":91.7825,"start":134,"end":336},{"cath_id":"1.10.287","chopping":"55-97","consensus_level":"medium","plddt":72.2063,"start":55,"end":97}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/P35611","model_url":"https://alphafold.ebi.ac.uk/files/AF-P35611-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-P35611-F1-predicted_aligned_error_v6.png","plddt_mean":64.88},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=ADD1","jax_strain_url":"https://www.jax.org/strain/search?query=ADD1"},"sequence":{"accession":"P35611","fasta_url":"https://rest.uniprot.org/uniprotkb/P35611.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/P35611/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/P35611"}},"corpus_meta":[{"pmid":"9539737","id":"PMC_9539737","title":"ADD1/SREBP1 activates PPARgamma through the production of endogenous ligand.","date":"1998","source":"Proceedings of the National Academy of Sciences of the United States of America","url":"https://pubmed.ncbi.nlm.nih.gov/9539737","citation_count":555,"is_preprint":false},{"pmid":"8336713","id":"PMC_8336713","title":"ADD1: a novel helix-loop-helix transcription factor associated with adipocyte determination and differentiation.","date":"1993","source":"Molecular and cellular biology","url":"https://pubmed.ncbi.nlm.nih.gov/8336713","citation_count":512,"is_preprint":false},{"pmid":"7739539","id":"PMC_7739539","title":"Dual DNA binding specificity of ADD1/SREBP1 controlled by a single amino acid in the basic helix-loop-helix domain.","date":"1995","source":"Molecular and cellular biology","url":"https://pubmed.ncbi.nlm.nih.gov/7739539","citation_count":294,"is_preprint":false},{"pmid":"15466874","id":"PMC_15466874","title":"Regulatory role of glycogen synthase kinase 3 for transcriptional activity of ADD1/SREBP1c.","date":"2004","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/15466874","citation_count":89,"is_preprint":false},{"pmid":"12052841","id":"PMC_12052841","title":"ADD1 460W allele associated with cardiovascular disease in hypertensive individuals.","date":"2002","source":"Hypertension (Dallas, Tex. : 1979)","url":"https://pubmed.ncbi.nlm.nih.gov/12052841","citation_count":63,"is_preprint":false},{"pmid":"10585876","id":"PMC_10585876","title":"Functional antagonism between inhibitor of DNA binding (Id) and adipocyte determination and differentiation factor 1/sterol regulatory element-binding protein-1c (ADD1/SREBP-1c) trans-factors for the regulation of fatty acid synthase promoter in adipocytes.","date":"1999","source":"The Biochemical journal","url":"https://pubmed.ncbi.nlm.nih.gov/10585876","citation_count":62,"is_preprint":false},{"pmid":"14654692","id":"PMC_14654692","title":"Twist2, a novel ADD1/SREBP1c interacting protein, represses the transcriptional activity of ADD1/SREBP1c.","date":"2003","source":"Nucleic acids research","url":"https://pubmed.ncbi.nlm.nih.gov/14654692","citation_count":49,"is_preprint":false},{"pmid":"23691048","id":"PMC_23691048","title":"Lower ADD1 gene promoter DNA methylation increases the risk of essential hypertension.","date":"2013","source":"PloS one","url":"https://pubmed.ncbi.nlm.nih.gov/23691048","citation_count":48,"is_preprint":false},{"pmid":"22307086","id":"PMC_22307086","title":"A role for α-adducin (ADD-1) in nematode and human memory.","date":"2012","source":"The EMBO journal","url":"https://pubmed.ncbi.nlm.nih.gov/22307086","citation_count":48,"is_preprint":false},{"pmid":"10361996","id":"PMC_10361996","title":"Age-related adipose tissue mRNA expression of ADD1/SREBP1, PPARgamma, lipoprotein lipase, and GLUT4 glucose transporter in rhesus monkeys.","date":"1999","source":"The journals of gerontology. Series A, Biological sciences and medical sciences","url":"https://pubmed.ncbi.nlm.nih.gov/10361996","citation_count":40,"is_preprint":false},{"pmid":"31805646","id":"PMC_31805646","title":"DNA Methylation of Candidate Genes (ACE II, IFN-γ, AGTR 1, CKG, ADD1, SCNN1B and TLR2) in Essential Hypertension: A Systematic Review and Quantitative Evidence Synthesis.","date":"2019","source":"International journal of environmental research and public health","url":"https://pubmed.ncbi.nlm.nih.gov/31805646","citation_count":35,"is_preprint":false},{"pmid":"12885793","id":"PMC_12885793","title":"Interaction between ACE and ADD1 gene polymorphisms in the progression of IgA nephropathy in Japanese patients.","date":"2003","source":"Hypertension (Dallas, Tex. : 1979)","url":"https://pubmed.ncbi.nlm.nih.gov/12885793","citation_count":28,"is_preprint":false},{"pmid":"15474463","id":"PMC_15474463","title":"Effect of Add1 gene transfer on blood pressure in reciprocal congenic strains of Milan rats.","date":"2004","source":"Biochemical and biophysical research communications","url":"https://pubmed.ncbi.nlm.nih.gov/15474463","citation_count":27,"is_preprint":false},{"pmid":"21194526","id":"PMC_21194526","title":"A study of ACE and ADD1 polymorphism in ischemic and hemorrhagic stroke.","date":"2010","source":"Clinica chimica acta; international journal of clinical chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/21194526","citation_count":24,"is_preprint":false},{"pmid":"19962449","id":"PMC_19962449","title":"ADD1/SREBP1c activates the PGC1-alpha promoter in brown adipocytes.","date":"2009","source":"Biochimica et biophysica acta","url":"https://pubmed.ncbi.nlm.nih.gov/19962449","citation_count":22,"is_preprint":false},{"pmid":"7959767","id":"PMC_7959767","title":"The murine homologues of the Huntington disease gene (Hdh) and the alpha-adducin gene (Add1) map to mouse chromosome 5 within a region of conserved synteny with human chromosome 4p16.3.","date":"1994","source":"Genomics","url":"https://pubmed.ncbi.nlm.nih.gov/7959767","citation_count":21,"is_preprint":false},{"pmid":"23863317","id":"PMC_23863317","title":"Effects of ACE and ADD1 gene polymorphisms on blood pressure response to hydrochlorothiazide: a meta-analysis.","date":"2013","source":"International journal of clinical pharmacology and therapeutics","url":"https://pubmed.ncbi.nlm.nih.gov/23863317","citation_count":20,"is_preprint":false},{"pmid":"16450155","id":"PMC_16450155","title":"Hydrochlorothiazide efficacy and polymorphisms in ACE, ADD1 and GNB3 in healthy, male volunteers.","date":"2006","source":"European journal of clinical pharmacology","url":"https://pubmed.ncbi.nlm.nih.gov/16450155","citation_count":20,"is_preprint":false},{"pmid":"15896329","id":"PMC_15896329","title":"Transcriptional regulation of mouse 6-phosphogluconate dehydrogenase by ADD1/SREBP1c.","date":"2005","source":"Biochemical and biophysical research communications","url":"https://pubmed.ncbi.nlm.nih.gov/15896329","citation_count":20,"is_preprint":false},{"pmid":"11309661","id":"PMC_11309661","title":"Identification of a mutation in ADD1/SREBP-1 in the spontaneously hypertensive rat.","date":"2001","source":"Mammalian genome : official journal of the International Mammalian Genome Society","url":"https://pubmed.ncbi.nlm.nih.gov/11309661","citation_count":16,"is_preprint":false},{"pmid":"20838486","id":"PMC_20838486","title":"Gly460Trp polymorphism of the ADD1 gene and essential hypertension in an Indian population: A meta-analysis on hypertension risk.","date":"2010","source":"Indian journal of human genetics","url":"https://pubmed.ncbi.nlm.nih.gov/20838486","citation_count":16,"is_preprint":false},{"pmid":"25567773","id":"PMC_25567773","title":"The interactions between alcohol consumption and DNA methylation of the ADD1 gene promoter modulate essential hypertension susceptibility in a population-based, case-control study.","date":"2015","source":"Hypertension research : official journal of the Japanese Society of Hypertension","url":"https://pubmed.ncbi.nlm.nih.gov/25567773","citation_count":16,"is_preprint":false},{"pmid":"11212213","id":"PMC_11212213","title":"Weight loss reduces expression of SREBP1c/ADD1 and PPARgamma2 in adipose tissue of obese women.","date":"2001","source":"Pflugers Archiv : European journal of physiology","url":"https://pubmed.ncbi.nlm.nih.gov/11212213","citation_count":15,"is_preprint":false},{"pmid":"37156877","id":"PMC_37156877","title":"Cathepsin B S-nitrosylation promotes ADAR1-mediated editing of its own mRNA transcript via an ADD1/MATR3 regulatory axis.","date":"2023","source":"Cell research","url":"https://pubmed.ncbi.nlm.nih.gov/37156877","citation_count":14,"is_preprint":false},{"pmid":"34906466","id":"PMC_34906466","title":"Variants in ADD1 cause intellectual disability, corpus callosum dysgenesis, and ventriculomegaly in humans.","date":"2021","source":"Genetics in medicine : official journal of the American College of Medical Genetics","url":"https://pubmed.ncbi.nlm.nih.gov/34906466","citation_count":14,"is_preprint":false},{"pmid":"26042478","id":"PMC_26042478","title":"Association of alpha-ADD1 Gene and Hypertension Risk: A Meta-Analysis.","date":"2015","source":"Medical science monitor : international medical journal of experimental and clinical research","url":"https://pubmed.ncbi.nlm.nih.gov/26042478","citation_count":11,"is_preprint":false},{"pmid":"25816007","id":"PMC_25816007","title":"A phosphorylation-related variant ADD1-rs4963 modifies the risk of colorectal cancer.","date":"2015","source":"PloS one","url":"https://pubmed.ncbi.nlm.nih.gov/25816007","citation_count":11,"is_preprint":false},{"pmid":"10429360","id":"PMC_10429360","title":"The ADD1 G460W polymorphism is not associated with variation in blood pressure in Canadian Oji-Cree.","date":"1999","source":"Journal of human genetics","url":"https://pubmed.ncbi.nlm.nih.gov/10429360","citation_count":11,"is_preprint":false},{"pmid":"9121491","id":"PMC_9121491","title":"An adipogenic basic helix-loop-helix-leucine zipper type transcription factor (ADD1) mRNA is expressed and regulated by retinoic acid in osteoblastic cells.","date":"1996","source":"Molecular endocrinology (Baltimore, Md.)","url":"https://pubmed.ncbi.nlm.nih.gov/9121491","citation_count":10,"is_preprint":false},{"pmid":"27340988","id":"PMC_27340988","title":"Angiotensin-Converting Enzyme (ACE) I/D and Alpha-Adducin (ADD1) G460W Gene Polymorphisms in Turkish Patients with Severe Chronic Tinnitus.","date":"2016","source":"The journal of international advanced otology","url":"https://pubmed.ncbi.nlm.nih.gov/27340988","citation_count":10,"is_preprint":false},{"pmid":"22810272","id":"PMC_22810272","title":"Computational study of ADD1 gene polymorphism associated with hypertension.","date":"2013","source":"Cell biochemistry and biophysics","url":"https://pubmed.ncbi.nlm.nih.gov/22810272","citation_count":8,"is_preprint":false},{"pmid":"29049185","id":"PMC_29049185","title":"Relationship between ADD1 Gly460Trp gene polymorphism and essential hypertension in Madeira Island.","date":"2017","source":"Medicine","url":"https://pubmed.ncbi.nlm.nih.gov/29049185","citation_count":6,"is_preprint":false},{"pmid":"32971583","id":"PMC_32971583","title":"Association of TBXA2R, P2Y12 and ADD1 genes polymorphisms with ischemic stroke susceptibility: A metaanalysis.","date":"2020","source":"Clinical and investigative medicine. Medecine clinique et experimentale","url":"https://pubmed.ncbi.nlm.nih.gov/32971583","citation_count":6,"is_preprint":false},{"pmid":"30062972","id":"PMC_30062972","title":"Alpha Adducin (ADD1) Gene Polymorphism and New Onset of Diabetes Under the Influence of Selective Antihypertensive Therapy in Essential Hypertension.","date":"2019","source":"Current hypertension reviews","url":"https://pubmed.ncbi.nlm.nih.gov/30062972","citation_count":6,"is_preprint":false},{"pmid":"23540412","id":"PMC_23540412","title":"ACE and ADD1 gene in extra and intracranial atherosclerosis in ischaemic stroke.","date":"2013","source":"Neurological research","url":"https://pubmed.ncbi.nlm.nih.gov/23540412","citation_count":6,"is_preprint":false},{"pmid":"20872252","id":"PMC_20872252","title":"A large indel mutation of the bovine ADD1/SREBP1c gene and its effects on growth traits in some native cattle breeds from China.","date":"2010","source":"Molecular biology reports","url":"https://pubmed.ncbi.nlm.nih.gov/20872252","citation_count":6,"is_preprint":false},{"pmid":"20473689","id":"PMC_20473689","title":"Polymorphisms in the GNB3 and ADD1 genes and blood pressure in a Chinese population.","date":"2010","source":"Human genetics","url":"https://pubmed.ncbi.nlm.nih.gov/20473689","citation_count":5,"is_preprint":false},{"pmid":"22476228","id":"PMC_22476228","title":"Association between genetic variants of the ADD1 and GNB3 genes and blood pressure response to the cold pressor test in a Chinese Han population: the GenSalt Study.","date":"2012","source":"Hypertension research : official journal of the Japanese Society of Hypertension","url":"https://pubmed.ncbi.nlm.nih.gov/22476228","citation_count":5,"is_preprint":false},{"pmid":"34055401","id":"PMC_34055401","title":"The Association between Gly460Trp-Polymorphism of Alpha-Adducin 1 Gene (ADD1) and Arterial Hypertension Development in Ukrainian Population.","date":"2021","source":"International journal of hypertension","url":"https://pubmed.ncbi.nlm.nih.gov/34055401","citation_count":5,"is_preprint":false},{"pmid":"26535708","id":"PMC_26535708","title":"Development of FQ-PCR method to determine the level of ADD1 expression in fatty and lean pigs.","date":"2015","source":"Genetics and molecular research : GMR","url":"https://pubmed.ncbi.nlm.nih.gov/26535708","citation_count":3,"is_preprint":false},{"pmid":"22926980","id":"PMC_22926980","title":"Strain-specific hyperkyphosis and megaesophagus in Add1 null mice.","date":"2012","source":"Genesis (New York, N.Y. : 2000)","url":"https://pubmed.ncbi.nlm.nih.gov/22926980","citation_count":3,"is_preprint":false},{"pmid":"16520310","id":"PMC_16520310","title":"[Distributions of polymorphism of ADD1, MC4R, H-FABP gene, associated with IMF and BF in 3 populations in pig].","date":"2006","source":"Yi chuan = Hereditas","url":"https://pubmed.ncbi.nlm.nih.gov/16520310","citation_count":3,"is_preprint":false},{"pmid":"29527980","id":"PMC_29527980","title":"Genetic Variants in ADD1 Gene and their Associations with Growth Traits in Cattle.","date":"2018","source":"Animal biotechnology","url":"https://pubmed.ncbi.nlm.nih.gov/29527980","citation_count":2,"is_preprint":false},{"pmid":"37761873","id":"PMC_37761873","title":"Mechanisms of Regulation of the CHRDL1 Gene by the TWIST2 and ADD1/SREBP1c Transcription Factors.","date":"2023","source":"Genes","url":"https://pubmed.ncbi.nlm.nih.gov/37761873","citation_count":1,"is_preprint":false},{"pmid":"40421935","id":"PMC_40421935","title":"ICAM1 778G>A (rs1799969), ADD1 1378G>T (rs4961), NPPA 553T>C (rs5065), and NOS3 894G>T (rs1799983) Variants in Infants with Gastroschisis from Western Mexico.","date":"2025","source":"Genetic testing and molecular biomarkers","url":"https://pubmed.ncbi.nlm.nih.gov/40421935","citation_count":0,"is_preprint":false},{"pmid":null,"id":"bio_10.1101_2024.11.08.622634","title":"Adducins regulate morphology and fate of neural progenitors during neocortical neurogenesis","date":"2024-11-08","source":"bioRxiv","url":"https://doi.org/10.1101/2024.11.08.622634","citation_count":0,"is_preprint":true}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":24088,"output_tokens":3190,"usd":0.060057},"stage2":{"model":"claude-opus-4-6","input_tokens":6636,"output_tokens":3040,"usd":0.16377},"total_usd":0.223827,"stage1_batch_id":"msgbatch_01TqNM6p6FsoMBT2jzQTwKBr","stage2_batch_id":"msgbatch_01Ya473eco8sTHbvRymQaU8o","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 1993,\n      \"finding\": \"ADD1 is a novel basic helix-loop-helix leucine zipper transcription factor that binds sequence-specifically to an E-box motif in the fatty acid synthase gene promoter and activates transcription in a differentiation-dependent manner in adipocytes.\",\n      \"method\": \"Oligonucleotide screening of adipocyte cDNA library, CAT reporter assays, sequence-specific DNA binding\",\n      \"journal\": \"Molecular and cellular biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 — original discovery with DNA binding and transcriptional activation assays, foundational paper with 512 citations\",\n      \"pmids\": [\"8336713\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1995,\n      \"finding\": \"ADD1/SREBP1 has dual DNA sequence specificity, binding both E-box (ATCACGTGA) and SRE-1 (ATCACCCCAC) motifs; this dual specificity is controlled by a single atypical tyrosine residue in the basic region — substituting it with arginine restricts binding to E-box only, while introducing tyrosine into USF confers dual specificity.\",\n      \"method\": \"PCR-amplified binding analysis, site-directed mutagenesis, promoter-reporter (CAT) transcriptional assays\",\n      \"journal\": \"Molecular and cellular biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 — mutagenesis with functional validation, 294 citations, multiple orthogonal methods\",\n      \"pmids\": [\"7739539\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1998,\n      \"finding\": \"ADD1/SREBP1 activates PPARγ specifically through its ligand-binding domain by stimulating production and secretion of endogenous lipid ligand(s) that directly bind PPARγ and displace radiolabeled thiazolidinedione.\",\n      \"method\": \"Gal4-LBD fusion reporter assays, conditioned medium transfer experiments, radioligand displacement binding assay\",\n      \"journal\": \"Proceedings of the National Academy of Sciences of the United States of America\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 — multiple orthogonal methods including direct ligand binding assay; 555 citations\",\n      \"pmids\": [\"9539737\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1999,\n      \"finding\": \"Id2 and Id3 proteins physically interact with ADD1/SREBP1c and inhibit its DNA binding to the fatty acid synthase promoter, thereby repressing ADD1/SREBP1c-dependent transcription in adipocytes.\",\n      \"method\": \"Gel mobility-shift assays (EMSA), co-immunoprecipitation of in vitro-translated proteins, CAT reporter assays in adipocytes\",\n      \"journal\": \"The Biochemical journal\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 — reciprocal co-IP plus EMSA plus functional reporter assays\",\n      \"pmids\": [\"10585876\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2003,\n      \"finding\": \"Twist2 (Dermo-1) physically interacts with the N-terminal domain of ADD1/SREBP1c, reduces its binding to target DNA sequences, and represses its transcriptional activity; this repression is partly dependent on HDAC activity.\",\n      \"method\": \"Yeast two-hybrid screen with adipocyte cDNA library, co-immunoprecipitation, luciferase reporter assays, HDAC inhibitor treatment\",\n      \"journal\": \"Nucleic acids research\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — yeast two-hybrid confirmed by co-IP, functional rescue with HDAC inhibitors, multiple orthogonal methods\",\n      \"pmids\": [\"14654692\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2004,\n      \"finding\": \"GSK3β phosphorylates ADD1/SREBP1c in vitro and in vivo and negatively regulates its transcriptional activity; GSK3 inhibition enhances ADD1/SREBP1c target gene expression (FAS, ACC1, SCD1) without requiring de novo protein synthesis, indicating regulation at the post-translational level.\",\n      \"method\": \"In vitro kinase assay, in vivo phosphorylation assay, GSK3 inhibitor treatment, overexpression of GSK3β, luciferase reporter assays, cycloheximide chase\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 — in vitro kinase assay plus in vivo phosphorylation plus functional reporters with multiple controls\",\n      \"pmids\": [\"15466874\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2005,\n      \"finding\": \"ADD1/SREBP1c directly regulates mouse 6-phosphogluconate dehydrogenase (6PGDH) gene expression by binding an E-box motif in its promoter; insulin-dependent 6PGDH induction is mediated through ADD1/SREBP1c via the PI3-kinase pathway.\",\n      \"method\": \"DNase I footprinting assay, point mutation analysis, reporter assays, PI3-kinase inhibitor treatment\",\n      \"journal\": \"Biochemical and biophysical research communications\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1 — footprinting and mutagenesis with functional reporters, single lab\",\n      \"pmids\": [\"15896329\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"ADD1/SREBP1c directly induces PGC1α expression by binding a conserved E-box in the proximal PGC1α promoter; β-adrenergic stimulation recruits ADD1/SREBP1c to this E-box in brown adipocytes.\",\n      \"method\": \"Luciferase reporter assays, chromatin immunoprecipitation (ChIP), adrenergic receptor agonist treatment\",\n      \"journal\": \"Biochimica et biophysica acta\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — ChIP plus reporter assays, single lab\",\n      \"pmids\": [\"19962449\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"In C. elegans, α-adducin (add-1) is required for consolidation of synaptic plasticity and sustained synaptic increase of AMPA-type glutamate receptor (GLR-1) content through its actin-capping activity in a splice-form- and tissue-specific manner; human ADD1 expression in nematodes fully rescues loss of C. elegans add-1 function.\",\n      \"method\": \"Loss-of-function genetics, live imaging of GLR-1 turnover, aversive olfactory associative learning assays, human ADD1 rescue in C. elegans\",\n      \"journal\": \"The EMBO journal\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — multiple orthogonal methods (genetics, live imaging, cross-species rescue), functional conservation validated\",\n      \"pmids\": [\"22307086\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"Add1 knockout mice develop strain-dependent hyperkyphosis, megaesophagus, and reduced axon numbers in peripheral nerves, revealing non-erythroid functions for α-adducin in neural and skeletal tissue.\",\n      \"method\": \"Targeted gene deletion (knockout mice), histological and morphological analysis, peripheral nerve axon counting\",\n      \"journal\": \"Genesis (New York, N.Y. : 2000)\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — clean KO with defined non-erythroid phenotypic readouts, single lab\",\n      \"pmids\": [\"22926980\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"Loss-of-function ADD1 variants in humans cause corpus callosum dysgenesis, ventriculomegaly, and intellectual disability; ADD1 is required for dimerization with ADD2, and Add1 knockout mice recapitulate corpus callosum dysgenesis and ventriculomegaly.\",\n      \"method\": \"Exome sequencing, RNA sequencing, super-resolution imaging, immunoblotting, ADD1-ADD2 dimerization assay, Add1 knockout mouse phenotyping\",\n      \"journal\": \"Genetics in medicine : official journal of the American College of Medical Genetics\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — human genetics validated by mouse KO and molecular dimerization assays, multiple orthogonal methods\",\n      \"pmids\": [\"34906466\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"S-nitrosylation of cathepsin B promotes dephosphorylation and nuclear translocation of ADD1, which then recruits MATR3 and ADAR1 to CTSB mRNA, driving A-to-I RNA editing and increased CTSB mRNA stability via HuR binding.\",\n      \"method\": \"S-nitrosylation assay, subcellular fractionation/nuclear translocation assay, co-immunoprecipitation (ADD1-MATR3-ADAR1 complex), RNA editing sequencing, HuR binding assay, mRNA stability assay\",\n      \"journal\": \"Cell research\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 — multiple orthogonal biochemical methods establishing a novel regulatory axis, published in high-impact journal\",\n      \"pmids\": [\"37156877\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"ADD1/SREBP1c binds E-box elements in the CHRDL1 gene upstream region and activates its transcription; TWIST2 competes with ADD1/SREBP1c for binding to the same DNA site and blocks ADD1/SREBP1c-mediated activation.\",\n      \"method\": \"EMSA, luciferase reporter assays, EMSA competition assays\",\n      \"journal\": \"Genes\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1-2 — EMSA and reporter assays demonstrate direct competition, single lab\",\n      \"pmids\": [\"37761873\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"ADD1 (and other adducins) regulate the proliferation capacity and fate of basal neural progenitors during neocortical neurogenesis; ADD1 knockout in human cortical organoids reduces progenitor proliferation and causes aberrant neurogenesis, while adducin overexpression increases progenitor protrusions and proliferative capacity.\",\n      \"method\": \"In vivo mouse and ferret neocortex overexpression, ADD1 knockout in human cortical organoids, immunohistochemistry, progenitor counting\",\n      \"journal\": \"bioRxiv\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — KO in organoids plus in vivo gain-of-function in multiple species, but preprint not yet peer-reviewed\",\n      \"pmids\": [\"bio_10.1101_2024.11.08.622634\"],\n      \"is_preprint\": true\n    }\n  ],\n  \"current_model\": \"ADD1 (adducin α-subunit / SREBP1c) functions as a basic HLH-leucine zipper transcription factor that activates lipogenic and adipogenic gene expression by binding E-box and SRE-1 motifs (dual specificity controlled by a single tyrosine in the basic region), activates PPARγ by producing endogenous lipid ligands, is negatively regulated post-translationally by GSK3β-mediated phosphorylation and by interacting repressors (Id2/3, Twist2), drives PGC1α expression in brown adipocytes, and—in its role as an actin-capping cytoskeletal protein—controls synaptic AMPA receptor trafficking for memory consolidation, nuclear translocation to recruit the MATR3/ADAR1 RNA-editing complex upon S-nitrosylation signaling, and neural progenitor proliferation and fate during neocortical development.\"\n}\n```","stage2_raw":"```json\n{\n  \"mechanistic_narrative\": \"ADD1 encodes α-adducin, a multifunctional protein that operates both as a cytoskeletal actin-capping protein regulating membrane-cytoskeleton interactions and, through its SREBP1c isoform, as a basic helix-loop-helix-leucine zipper transcription factor controlling lipogenic and adipogenic gene expression. As a transcription factor (ADD1/SREBP1c), it binds both E-box and SRE-1 DNA motifs—a dual specificity governed by a single atypical tyrosine in its basic region—to activate fatty acid synthase, 6-phosphogluconate dehydrogenase, PGC1α, and CHRDL1, and it stimulates PPARγ activity by producing endogenous lipid ligands; its transcriptional output is negatively regulated by GSK3β-mediated phosphorylation and by inhibitory interactions with Id2/Id3 and Twist2 [PMID:7739539, PMID:9539737, PMID:15466874, PMID:10585876, PMID:14654692]. In its cytoskeletal capacity, ADD1's actin-capping activity is required for consolidation of synaptic AMPA receptor content and associative memory, and upon S-nitrosylation signaling it translocates to the nucleus where it recruits a MATR3/ADAR1 complex to drive A-to-I RNA editing of cathepsin B mRNA [PMID:22307086, PMID:37156877]. Loss-of-function ADD1 variants in humans cause corpus callosum dysgenesis, ventriculomegaly, and intellectual disability, phenotypes recapitulated in Add1 knockout mice [PMID:34906466].\",\n  \"teleology\": [\n    {\n      \"year\": 1993,\n      \"claim\": \"The identification of ADD1 as a bHLH-LZ transcription factor that binds the fatty acid synthase E-box and activates transcription in adipocytes established the gene's primary molecular identity as a lipogenic transcriptional regulator.\",\n      \"evidence\": \"Oligonucleotide screening of adipocyte cDNA library with CAT reporter assays and DNA-binding analysis\",\n      \"pmids\": [\"8336713\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Mechanism of differentiation-dependent activation not resolved\", \"Relationship to SREBP family not yet established\"]\n    },\n    {\n      \"year\": 1995,\n      \"claim\": \"Demonstrating that a single tyrosine in the basic region confers dual E-box/SRE-1 DNA-binding specificity resolved how one transcription factor can regulate both cholesterol and fatty acid pathway promoters.\",\n      \"evidence\": \"Site-directed mutagenesis with PCR-amplified binding analysis and CAT reporter assays\",\n      \"pmids\": [\"7739539\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Structural basis for tyrosine-mediated dual recognition not determined at atomic resolution\", \"In vivo significance of dual specificity not tested\"]\n    },\n    {\n      \"year\": 1998,\n      \"claim\": \"Showing that ADD1/SREBP1c activates PPARγ by producing a secreted endogenous lipid ligand that displaces thiazolidinedione revealed a feed-forward lipogenic circuit linking SREBP1c to nuclear receptor activation.\",\n      \"evidence\": \"Gal4-LBD fusion reporter assays, conditioned-medium transfer, and radioligand displacement binding assay\",\n      \"pmids\": [\"9539737\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Chemical identity of the endogenous PPARγ ligand not determined\", \"Physiological relevance in intact adipose tissue not shown\"]\n    },\n    {\n      \"year\": 1999,\n      \"claim\": \"Identification of Id2/Id3 as physical interactors that inhibit ADD1/SREBP1c DNA binding established a dominant-negative regulatory mechanism for lipogenic transcription.\",\n      \"evidence\": \"EMSA, co-immunoprecipitation of in vitro-translated proteins, and CAT reporter assays in adipocytes\",\n      \"pmids\": [\"10585876\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"In vivo relevance of Id-mediated repression in lipid metabolism not tested\", \"Stoichiometry of Id–SREBP1c complexes unknown\"]\n    },\n    {\n      \"year\": 2003,\n      \"claim\": \"Twist2 was found to repress ADD1/SREBP1c by physical interaction and reduced DNA binding in an HDAC-dependent manner, revealing a second class of bHLH-mediated transcriptional repression targeting lipogenesis.\",\n      \"evidence\": \"Yeast two-hybrid screen, co-immunoprecipitation, luciferase reporters, and HDAC inhibitor rescue\",\n      \"pmids\": [\"14654692\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Which specific HDACs are recruited to the Twist2–SREBP1c complex is unknown\", \"Physiological context for Twist2–SREBP1c antagonism not defined in vivo\"]\n    },\n    {\n      \"year\": 2004,\n      \"claim\": \"Demonstrating that GSK3β phosphorylates ADD1/SREBP1c and suppresses its transcriptional activity post-translationally identified an insulin-responsive kinase switch controlling lipogenic gene expression.\",\n      \"evidence\": \"In vitro and in vivo kinase assays, GSK3 inhibitor treatment, luciferase reporters, cycloheximide chase\",\n      \"pmids\": [\"15466874\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Specific phosphorylation sites mapped by GSK3β on SREBP1c not fully characterized\", \"Interplay between GSK3β phosphorylation and proteasomal degradation not resolved\"]\n    },\n    {\n      \"year\": 2009,\n      \"claim\": \"ChIP evidence that β-adrenergic stimulation recruits ADD1/SREBP1c to a conserved E-box in the PGC1α promoter connected lipogenic transcription factor activity to thermogenic gene regulation in brown adipocytes.\",\n      \"evidence\": \"Chromatin immunoprecipitation and luciferase reporter assays in brown adipocytes treated with adrenergic agonist\",\n      \"pmids\": [\"19962449\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Whether ADD1/SREBP1c is necessary for cold-induced PGC1α expression in vivo is untested\", \"Mechanism linking β-adrenergic signaling to SREBP1c chromatin recruitment not elucidated\"]\n    },\n    {\n      \"year\": 2012,\n      \"claim\": \"Cross-species genetic studies established that α-adducin's actin-capping activity is required for synaptic AMPA receptor retention and memory consolidation, separating its cytoskeletal function from its transcription factor role.\",\n      \"evidence\": \"C. elegans loss-of-function genetics, live GLR-1 imaging, olfactory learning assays, and human ADD1 rescue\",\n      \"pmids\": [\"22307086\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Mechanism by which actin-capping stabilizes AMPA receptors at postsynaptic sites not defined\", \"Whether mammalian synaptic plasticity uses the same splice-form dependence is unknown\"]\n    },\n    {\n      \"year\": 2012,\n      \"claim\": \"Add1 knockout mice displaying hyperkyphosis, megaesophagus, and reduced peripheral nerve axon numbers revealed non-erythroid developmental roles for α-adducin.\",\n      \"evidence\": \"Targeted gene deletion in mice with histological and morphological analysis\",\n      \"pmids\": [\"22926980\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Strain dependence of phenotypes not mechanistically explained\", \"Cell-autonomous versus non-autonomous roles of ADD1 in these tissues not distinguished\"]\n    },\n    {\n      \"year\": 2021,\n      \"claim\": \"Human genetic evidence that loss-of-function ADD1 variants cause corpus callosum dysgenesis and intellectual disability, recapitulated in knockout mice, established ADD1 as a Mendelian disease gene for neurodevelopmental malformation.\",\n      \"evidence\": \"Exome sequencing in affected families, super-resolution imaging, ADD1-ADD2 dimerization assay, Add1 knockout mouse phenotyping\",\n      \"pmids\": [\"34906466\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"How disrupted ADD1–ADD2 dimerization leads to corpus callosum dysgenesis at the cellular level is unknown\", \"Whether heterozygous carriers show intermediate phenotypes is not addressed\"]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Discovery that dephosphorylated ADD1 translocates to the nucleus and recruits a MATR3/ADAR1 complex for A-to-I RNA editing of CTSB mRNA revealed an unexpected nuclear function for the cytoskeletal protein in RNA processing.\",\n      \"evidence\": \"S-nitrosylation assay, subcellular fractionation, co-immunoprecipitation of ADD1–MATR3–ADAR1, RNA editing sequencing, mRNA stability assay\",\n      \"pmids\": [\"37156877\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Whether ADD1 recruits MATR3/ADAR1 to other mRNA targets beyond CTSB is unknown\", \"Signal that triggers ADD1 dephosphorylation downstream of S-nitrosylation not fully delineated\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"It remains unresolved how the cytoskeletal and transcriptional functions of ADD1 are coordinated in the same cell, whether ADD1-dependent RNA editing extends to a broad set of transcripts, and what the structural basis is for the ADD1–ADD2 dimer in neurodevelopment.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Low\",\n      \"gaps\": [\"No structural model for the ADD1–ADD2 heterodimer\", \"Genome-wide identification of ADD1-dependent RNA editing targets not performed\", \"Integration of cytoskeletal versus transcriptional versus RNA-editing functions in a unified signaling framework is lacking\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0003677\", \"supporting_discovery_ids\": [0, 1, 6, 7, 12]},\n      {\"term_id\": \"GO:0140110\", \"supporting_discovery_ids\": [0, 1, 2, 5, 6, 7, 12]},\n      {\"term_id\": \"GO:0008092\", \"supporting_discovery_ids\": [8]},\n      {\"term_id\": \"GO:0003723\", \"supporting_discovery_ids\": [11]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005634\", \"supporting_discovery_ids\": [0, 1, 7, 11]},\n      {\"term_id\": \"GO:0005829\", \"supporting_discovery_ids\": [8, 11]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-74160\", \"supporting_discovery_ids\": [0, 1, 5, 6, 7, 12]},\n      {\"term_id\": \"R-HSA-1430728\", \"supporting_discovery_ids\": [0, 2, 5, 6]},\n      {\"term_id\": \"R-HSA-1266738\", \"supporting_discovery_ids\": [10, 9]},\n      {\"term_id\": \"R-HSA-112316\", \"supporting_discovery_ids\": [8, 10]},\n      {\"term_id\": \"R-HSA-8953854\", \"supporting_discovery_ids\": [11]}\n    ],\n    \"complexes\": [\n      \"ADD1-ADD2 heterodimer\",\n      \"ADD1-MATR3-ADAR1 nuclear RNA-editing complex\"\n    ],\n    \"partners\": [\n      \"ADD2\",\n      \"MATR3\",\n      \"ADAR1\",\n      \"ID2\",\n      \"ID3\",\n      \"TWIST2\",\n      \"GSK3B\"\n    ],\n    \"other_free_text\": []\n  }\n}\n```"}