{"gene":"ACTN2","run_date":"2026-06-09T22:02:40","timeline":{"discoveries":[{"year":2016,"finding":"Two HCM-associated mutations in the calponin-homology domain of ACTN2 (A119T and G111V) cause small but distinct changes in the secondary and tertiary structure of the purified actin-binding domain (ABD), reduce F-actin binding affinity, and impair Z-disc localization and dynamic behaviour of full-length mEos2-tagged protein in adult cardiomyocytes.","method":"Circular dichroism, X-ray crystallography of purified ABD; F-actin co-sedimentation assay; expression of tagged full-length protein in adult cardiomyocytes with live-cell imaging","journal":"The Biochemical journal","confidence":"High","confidence_rationale":"Tier 1 / Moderate — in vitro structural (X-ray crystallography) and biochemical (F-actin binding) assays combined with cellular localization experiments in a single study, multiple orthogonal methods","pmids":["27287556"],"is_preprint":false},{"year":2022,"finding":"A pathogenic missense ACTN2 variant (c.740C>T) causes protein aggregation in hiPSC-derived cardiomyocytes, leading to activation of the ubiquitin-proteasome system and autophagy-lysosomal pathway, myofibrillar disarray, and force impairment in engineered heart tissues — defining proteopathy as a disease mechanism for ACTN2-associated cardiomyopathy.","method":"CRISPR/Cas9 heterozygous knock-in hiPSC lines; immunofluorescence, live-cell imaging, RNA-seq, mass spectrometry proteomics; engineered heart tissue contractility assays","journal":"Cells","confidence":"High","confidence_rationale":"Tier 2 / Strong — multiple orthogonal methods (proteomics, live imaging, functional contractility) in isogenic CRISPR hiPSC-CM models","pmids":["36078153"],"is_preprint":false},{"year":2023,"finding":"The ACTN2 p.Met228Thr variant destabilizes the mutant alpha-actinin-2 protein, triggering increased activity of the ubiquitin-proteasomal system; homozygous embryos show sarcomeric parameter abnormalities, cell-cycle defects, and mitochondrial dysfunction detected by unbiased proteomics, leading to embryonic lethality.","method":"Knock-in mouse model; echocardiography; High Resolution Episcopic Microscopy; unbiased proteomics; qPCR; Western blotting","journal":"Cells","confidence":"High","confidence_rationale":"Tier 2 / Moderate — in vivo mouse model with multiple orthogonal molecular readouts (proteomics, Western blot, morphology) in a single rigorous study","pmids":["36899856"],"is_preprint":false},{"year":2019,"finding":"De novo missense and deletion mutations in ACTN2 cause sarcomeric disorganization and impaired muscle force in vivo. Mutant alpha-actinin-2 localizes correctly to the Z-line in differentiating myotubes; zebrafish expressing mutant ACTN2 show motor deficits and sarcomeric disorganization, and AAV-transduced mouse muscles show impaired force and Z-line/core defects, while wild-type ACTN2 expression produces no such abnormalities.","method":"Exome sequencing; muscle biopsy ultrastructure; zebrafish and AAV-mouse in vivo expression of mutant vs. wild-type ACTN2; muscle force measurement in isolated muscles; immunofluorescence in differentiating myotubes","journal":"Acta neuropathologica","confidence":"High","confidence_rationale":"Tier 2 / Strong — two independent in vivo model systems (zebrafish and mouse) with functional force measurements and structural readouts, wild-type controls","pmids":["30701273"],"is_preprint":false},{"year":2026,"finding":"CDK1 phosphorylates ACTN2 at Thr308, and this phosphorylation regulates sarcomere assembly: CRISPR-Cas9 phospho-null (T308A) C2C12 cells differentiate rapidly and form robust sarcomeres, whereas phosphomimetic (T308D) cells fail to form organized sarcomeres, linking cell-cycle exit to sarcomere assembly via ACTN2 phosphorylation status.","method":"In vitro CDK1 kinase assay with wild-type and T308A mutant Actn2; CRISPR-Cas9 knock-in of T308A and T308D variants in C2C12 cells; immunofluorescence of sarcomere structure; proliferation assays","journal":"Physiological reports","confidence":"High","confidence_rationale":"Tier 1 / Moderate — in vitro kinase assay with mutagenesis validation combined with CRISPR knock-in functional cell model, multiple orthogonal readouts","pmids":["41953953"],"is_preprint":false},{"year":2024,"finding":"Protein-extending dominant frameshift variants in ACTN2 cause alpha-actinin-2 protein aggregation in C2C12 cells, whereas missense variants associated with recessive actininopathy do not produce detectable aggregates, establishing protein aggregation as the pathomechanism specifically for dominant protein-extending frameshift actininopathies.","method":"C2C12 cell model expressing frameshift and missense ACTN2 variants; immunofluorescence for aggregate detection","journal":"Annals of clinical and translational neurology","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — cell model with immunofluorescence, replicated across two publications (PMID 39095936 and preprint PMID 38293186) from same group, single method","pmids":["39095936","38293186"],"is_preprint":false},{"year":2024,"finding":"Knockdown of ACTN2 in H9c2 cardiomyocytes under chronic dexamethasone stress impairs calcium uptake and promotes hypertrophy via excessive activation of the MAPK/ERK cascade; pharmacological ERK inhibition partially reverses the hypertrophic morphology and molecular markers.","method":"siRNA knockdown of Actn2 in H9c2 cells; transcriptome analysis; Western blotting for ERK phosphorylation; ERK inhibitor rescue experiments; measurement of hypertrophic biomarkers","journal":"Genes & genomics","confidence":"Medium","confidence_rationale":"Tier 2 / Weak — clean siRNA knockdown with transcriptome + Western blot + pharmacological rescue, single lab, single cell line","pmids":["38990270"],"is_preprint":false},{"year":2020,"finding":"Under ER stress, the transcription factor XBP1 upregulates Actn2 promoter activity in C2C12 myotubes, while XBP1, ATF4, and ATF6 downregulate Actn3 promoter activity; chemical induction of ER stress increases Actn2 mRNA and keeps α-actinin-2 protein levels unchanged, whereas α-actinin-3 protein is decreased.","method":"Promoter activity assays (reporter constructs) with UPR transcription factor overexpression; RT-qPCR; Western blotting in C2C12 myotubes under ER stress induction","journal":"Journal of muscle research and cell motility","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — promoter reporter assays combined with mRNA and protein quantification, single lab, focused on transcriptional regulation","pmids":["32451822"],"is_preprint":false},{"year":2025,"finding":"PRDM9 promotes ACTN2 transcription through H3K4me3 histone modification; ACTN2 knockdown inhibits the Hippo pathway in vascular smooth muscle cells (VSMCs), exacerbating apoptosis and inflammation, and PDLIM1 interacts with ACTN2 to mediate VSMC function via Hippo-YAP signaling.","method":"shRNA knockdown and overexpression; ChIP-qPCR for PRDM9-H3K4me3 at ACTN2 locus; CRISPR-Cas9 PRDM9 editing; co-immunoprecipitation/interaction screening for PDLIM1; functional rescue experiments; Western blot, ELISA, immunofluorescence","journal":"Frontiers in molecular neuroscience","confidence":"Medium","confidence_rationale":"Tier 2 / Weak — ChIP-qPCR and CRISPR validation for epigenetic regulation, co-IP for interaction, functional rescue, single lab","pmids":["40881324"],"is_preprint":false},{"year":2025,"finding":"RBFOX2 haploinsufficiency reduces ACTN2 expression in differentiating cardiomyocytes; overexpression of ACTN2 rescues contractility in RBFOX2 heterozygous but not null hiPSC-derived cardiomyocytes, and this rescue triggers a mechanosensing feedback loop that upregulates RBFOX2 from the wild-type allele and promotes transcriptome maturation.","method":"RBFOX2 heterozygous and null hiPSC-CM models; ACTN2 overexpression rescue; contractility measurements; RNA-seq; mechanosensing assays","journal":"bioRxiv","confidence":"Medium","confidence_rationale":"Tier 2 / Weak — isogenic hiPSC-CM models with functional contractility readout and rescue experiment, preprint not yet peer-reviewed","pmids":["bio_10.1101_2025.10.28.685214"],"is_preprint":true},{"year":2024,"finding":"ACTN4 forms a heterodimeric complex with muscle-specific ACTN2 at the cardiac Z-disc, as supported by biochemical experiments and AI modeling; ACTN4 depletion from human iPSC-CMs stabilizes canonical sarcomere proteins and drives contractility-dependent hypertrophy, while ACTN4 overexpression destabilizes sarcomeres.","method":"Co-immunoprecipitation; immunofluorescence; AI structural modeling; siRNA depletion in hiPSC-CMs; contractility measurements; zebrafish loss-of-function","journal":"bioRxiv","confidence":"Medium","confidence_rationale":"Tier 2 / Weak — biochemical Co-IP plus functional depletion in two model systems, preprint not yet peer-reviewed","pmids":["bio_10.1101_2024.11.26.625523"],"is_preprint":true},{"year":2019,"finding":"Dominant missense mutations in ACTN2 cause adult-onset distal myopathy (actininopathy), establishing ACTN2 as a skeletal muscle disease gene distinct from its known cardiac roles.","method":"Whole-exome sequencing; co-segregation analysis in 4 families; muscle biopsy histopathology","journal":"Annals of neurology","confidence":"Low","confidence_rationale":"Tier 3 / Moderate — genetic and histopathological characterization without in vitro/in vivo mechanistic follow-up in this paper; no direct functional assay of mutant protein","pmids":["30900782"],"is_preprint":false}],"current_model":"ACTN2 encodes alpha-actinin-2, a Z-disc protein that crosslinks antiparallel actin filaments and links titin to the sarcomere Z-disk in cardiac and skeletal muscle; its calponin-homology ABD directly binds F-actin (HCM mutations reduce this affinity and impair Z-disc incorporation), its stability is regulated by CDK1-mediated phosphorylation at Thr308 (controlling cell-cycle-dependent sarcomere assembly), it forms a heterodimer with ACTN4 at the cardiac Z-disc, its transcription is driven by PRDM9 via H3K4me3 modification and by XBP1 under ER stress, pathogenic variants destabilize the protein and activate the ubiquitin-proteasome system (proteopathy), and protein-extending frameshift variants cause dominant disease through alpha-actinin-2 aggregation, while loss of ACTN2 function promotes cardiomyocyte hypertrophy via MAPK/ERK signaling."},"narrative":{"mechanistic_narrative":"ACTN2 encodes alpha-actinin-2, a Z-disc structural protein essential for sarcomere assembly and contractile function in cardiac and skeletal muscle [PMID:27287556, PMID:30701273]. Its calponin-homology actin-binding domain directly engages F-actin, and HCM-associated mutations in this domain perturb its structure, reduce F-actin binding affinity, and impair Z-disc localization and dynamics in cardiomyocytes [PMID:27287556]. The protein's incorporation into the sarcomere is gated by the cell cycle: CDK1 phosphorylates ACTN2 at Thr308, and phospho-null cells assemble robust sarcomeres while phosphomimetic cells fail, coupling cell-cycle exit to sarcomere maturation [PMID:41953953]. A recurrent disease theme is proteostatic failure — pathogenic missense and protein-extending frameshift variants destabilize or aggregate alpha-actinin-2, activating the ubiquitin-proteasome system and autophagy-lysosomal pathway and producing myofibrillar disarray, force impairment, and in mice embryonic lethality with mitochondrial and cell-cycle defects [PMID:36078153, PMID:36899856, PMID:39095936, PMID:38293186]. Beyond its structural role, loss of ACTN2 in stressed cardiomyocytes promotes hypertrophy through excessive MAPK/ERK activation [PMID:38990270], and its expression is transcriptionally controlled by XBP1 under ER stress and by PRDM9 via H3K4me3 [PMID:32451822, PMID:40881324]. Dominant missense mutations in ACTN2 cause adult-onset distal myopathy (actininopathy), extending its disease spectrum beyond cardiac muscle [PMID:30900782].","teleology":[{"year":2016,"claim":"Established at structural and biochemical resolution how disease mutations in the actin-binding domain impair ACTN2's core function — linking F-actin engagement to Z-disc integration.","evidence":"X-ray crystallography and circular dichroism of purified ABD with F-actin co-sedimentation and live-cell imaging of tagged full-length protein in adult cardiomyocytes","pmids":["27287556"],"confidence":"High","gaps":["Did not establish how reduced F-actin affinity propagates to contractile force in intact tissue","Only two HCM mutations examined"]},{"year":2019,"claim":"Demonstrated that ACTN2 mutations cause skeletal muscle disease in vivo, showing mutant protein localizes correctly yet still disorganizes the sarcomere and impairs force — a dominant-negative structural effect rather than simple mislocalization.","evidence":"Exome sequencing, zebrafish and AAV-mouse expression of mutant vs. wild-type ACTN2, isolated muscle force measurement, myotube immunofluorescence","pmids":["30701273"],"confidence":"High","gaps":["Molecular basis of disorganization despite correct Z-line targeting unresolved","Did not define proteostatic consequences"]},{"year":2019,"claim":"Defined ACTN2 as a skeletal-muscle disease gene through dominant missense mutations causing adult-onset distal myopathy, broadening its phenotype beyond cardiac roles.","evidence":"Whole-exome sequencing and co-segregation in 4 families with muscle biopsy histopathology","pmids":["30900782"],"confidence":"Low","gaps":["No in vitro or in vivo functional assay of mutant protein in this study","Mechanism connecting genotype to histopathology not established"]},{"year":2020,"claim":"Identified transcriptional control of ACTN2 under ER stress, showing XBP1 sustains alpha-actinin-2 levels while related ACTN3 is downregulated, distinguishing isoform-specific UPR regulation.","evidence":"Promoter reporter assays with UPR transcription factor overexpression, RT-qPCR and Western blotting in C2C12 myotubes under ER stress","pmids":["32451822"],"confidence":"Medium","gaps":["Direct XBP1 binding to the ACTN2 promoter not mapped","Physiological relevance in muscle tissue untested"]},{"year":2022,"claim":"Defined proteopathy as a disease mechanism — showing a pathogenic missense variant aggregates and triggers proteostatic clearance pathways with functional force loss in human cardiac tissue.","evidence":"Isogenic CRISPR knock-in hiPSC-CM lines with proteomics, live imaging, RNA-seq, and engineered heart tissue contractility","pmids":["36078153"],"confidence":"High","gaps":["Whether aggregation is cause or consequence of force loss not fully separated","Single variant studied"]},{"year":2023,"claim":"Extended the destabilization/proteostasis model in vivo, linking a destabilizing variant to UPS activation, cell-cycle and mitochondrial defects, and embryonic lethality.","evidence":"Knock-in mouse model with echocardiography, episcopic microscopy, unbiased proteomics, qPCR and Western blotting","pmids":["36899856"],"confidence":"High","gaps":["Causal hierarchy between sarcomeric, cell-cycle and mitochondrial phenotypes unresolved","Mechanism connecting alpha-actinin-2 loss to mitochondrial dysfunction unknown"]},{"year":2024,"claim":"Distinguished variant-class-specific pathomechanisms, showing protein-extending frameshift variants aggregate whereas recessive missense variants do not — tying aggregation specifically to dominant frameshift actininopathy.","evidence":"C2C12 cell expression of frameshift vs. missense variants with immunofluorescence aggregate detection","pmids":["39095936","38293186"],"confidence":"Medium","gaps":["Single method (immunofluorescence) without biochemical aggregate characterization","Effect on contractile function not measured"]},{"year":2024,"claim":"Revealed a signaling role beyond structure: ACTN2 loss under stress drives hypertrophy via MAPK/ERK, with pharmacological ERK inhibition partially rescuing.","evidence":"siRNA knockdown in H9c2 cells with transcriptomics, Western blot for ERK phosphorylation, and ERK inhibitor rescue","pmids":["38990270"],"confidence":"Medium","gaps":["Mechanism linking alpha-actinin-2 to ERK activation undefined","Single cell line and stress context"]},{"year":2024,"claim":"Identified ACTN4 as a heterodimeric partner of ACTN2 at the cardiac Z-disc whose level tunes sarcomere stability and contractility-dependent hypertrophy.","evidence":"Co-immunoprecipitation, AI structural modeling, siRNA depletion in hiPSC-CMs, contractility, and zebrafish loss-of-function (preprint)","pmids":["bio_10.1101_2024.11.26.625523"],"confidence":"Medium","gaps":["Preprint, not peer-reviewed","Stoichiometry and structural basis of heterodimer not biochemically resolved"]},{"year":2025,"claim":"Connected ACTN2 to epigenetic regulation and Hippo signaling, with PRDM9 driving its transcription and PDLIM1 interaction mediating vascular smooth muscle function.","evidence":"ChIP-qPCR, CRISPR PRDM9 editing, co-IP for PDLIM1, and functional rescue in VSMCs","pmids":["40881324"],"confidence":"Medium","gaps":["Role of ACTN2 in non-muscle VSMC context not independently confirmed","PDLIM1 interaction not reciprocally validated"]},{"year":2025,"claim":"Placed ACTN2 within a dosage-sensitive maturation feedback loop, where RBFOX2-dependent ACTN2 levels feed back through mechanosensing to drive cardiomyocyte transcriptome maturation.","evidence":"RBFOX2 heterozygous and null hiPSC-CM models with ACTN2 overexpression rescue, contractility, RNA-seq and mechanosensing assays (preprint)","pmids":["bio_10.1101_2025.10.28.685214"],"confidence":"Medium","gaps":["Preprint, not peer-reviewed","Molecular components of the mechanosensing feedback not defined"]},{"year":2026,"claim":"Established post-translational coupling of cell-cycle exit to sarcomere assembly via CDK1 phosphorylation of ACTN2 at Thr308.","evidence":"In vitro CDK1 kinase assay with mutagenesis and CRISPR knock-in of T308A/T308D in C2C12 cells with sarcomere imaging and proliferation assays","pmids":["41953953"],"confidence":"High","gaps":["How phosphorylation alters ACTN2 binding or localization mechanistically unresolved","In vivo relevance in developing heart untested"]},{"year":null,"claim":"How the distinct disease mechanisms (impaired actin binding, protein aggregation/proteostatic failure, and altered signaling) are integrated, and what determines the cardiac versus skeletal phenotype of a given variant, remains unresolved.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No unified model linking variant class to tissue-specific outcome","Structural basis of Thr308 phosphoregulation undefined","Mechanism of ACTN2-dependent ERK and Hippo signaling unknown"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0008092","term_label":"cytoskeletal protein binding","supporting_discovery_ids":[0,3]},{"term_id":"GO:0005198","term_label":"structural molecule activity","supporting_discovery_ids":[0,3]}],"localization":[{"term_id":"GO:0005856","term_label":"cytoskeleton","supporting_discovery_ids":[0,3,10]}],"pathway":[{"term_id":"R-HSA-397014","term_label":"Muscle contraction","supporting_discovery_ids":[0,3,4]},{"term_id":"R-HSA-392499","term_label":"Metabolism of proteins","supporting_discovery_ids":[1,2]}],"complexes":["cardiac Z-disc"],"partners":["ACTN4","PDLIM1"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"P35609","full_name":"Alpha-actinin-2","aliases":["Alpha-actinin skeletal muscle isoform 2","F-actin cross-linking protein"],"length_aa":894,"mass_kda":103.9,"function":"F-actin cross-linking protein which is thought to anchor actin to a variety of intracellular structures. This is a bundling protein","subcellular_location":"Cytoplasm, myofibril, sarcomere, Z line","url":"https://www.uniprot.org/uniprotkb/P35609/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/ACTN2","classification":"Not Classified","n_dependent_lines":2,"n_total_lines":1208,"dependency_fraction":0.0016556291390728477},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[],"url":"https://opencell.sf.czbiohub.org/search/ACTN2","total_profiled":1310},"omim":[{"mim_id":"620265","title":"CONGENITAL MYOPATHY 2B, SEVERE INFANTILE, AUTOSOMAL RECESSIVE; CMYO2B","url":"https://www.omim.org/entry/620265"},{"mim_id":"618655","title":"MYOPATHY, DISTAL, 6, ADULT-ONSET, AUTOSOMAL DOMINANT; MPD6","url":"https://www.omim.org/entry/618655"},{"mim_id":"618654","title":"CONGENITAL MYOPATHY 8; CMYO8","url":"https://www.omim.org/entry/618654"},{"mim_id":"614666","title":"COILED-COIL DOMAIN-CONTAINING PROTEIN 78; CCDC78","url":"https://www.omim.org/entry/614666"},{"mim_id":"612193","title":"CARDIOMYOPATHY-ASSOCIATED PROTEIN 5; CMYA5","url":"https://www.omim.org/entry/612193"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Approved","locations":[{"location":"Actin filaments","reliability":"Approved"},{"location":"Focal adhesion sites","reliability":"Approved"},{"location":"Primary cilium","reliability":"Additional"},{"location":"Primary cilium transition zone","reliability":"Additional"},{"location":"Cytosol","reliability":"Additional"}],"tissue_specificity":"Group enriched","tissue_distribution":"Detected in many","driving_tissues":[{"tissue":"heart muscle","ntpm":695.9},{"tissue":"skeletal muscle","ntpm":1961.6},{"tissue":"tongue","ntpm":1195.2}],"url":"https://www.proteinatlas.org/search/ACTN2"},"hgnc":{"alias_symbol":[],"prev_symbol":[]},"alphafold":{"accession":"P35609","domains":[{"cath_id":"1.10.418.10","chopping":"35-145","consensus_level":"medium","plddt":89.4723,"start":35,"end":145},{"cath_id":"1.20.58.60","chopping":"274-394","consensus_level":"medium","plddt":90.3866,"start":274,"end":394},{"cath_id":"1.20.58.60","chopping":"420-535_544-603","consensus_level":"medium","plddt":82.2864,"start":420,"end":603},{"cath_id":"1.10.238.10","chopping":"829-890","consensus_level":"medium","plddt":87.695,"start":829,"end":890}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/P35609","model_url":"https://alphafold.ebi.ac.uk/files/AF-P35609-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-P35609-F1-predicted_aligned_error_v6.png","plddt_mean":84.81},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=ACTN2","jax_strain_url":"https://www.jax.org/strain/search?query=ACTN2"},"sequence":{"accession":"P35609","fasta_url":"https://rest.uniprot.org/uniprotkb/P35609.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/P35609/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/P35609"}},"corpus_meta":[{"pmid":"25224718","id":"PMC_25224718","title":"Exome 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Case reports","url":"https://pubmed.ncbi.nlm.nih.gov/40977946","citation_count":1,"is_preprint":false},{"pmid":"41953953","id":"PMC_41953953","title":"Cell-cycle regulation of sarcomere integrity-Role for Actn2 phosphorylation.","date":"2026","source":"Physiological reports","url":"https://pubmed.ncbi.nlm.nih.gov/41953953","citation_count":0,"is_preprint":false},{"pmid":"39543892","id":"PMC_39543892","title":"Evaluation of EDARADD, LPO and ACTN2 genes polymorphisms in children with dental caries compared to caries-free controls.","date":"2024","source":"The Journal of clinical pediatric dentistry","url":"https://pubmed.ncbi.nlm.nih.gov/39543892","citation_count":0,"is_preprint":false},{"pmid":"40881324","id":"PMC_40881324","title":"ACTN2, regulated by PRDM9, affects the growth and inflammation of vascular smooth muscle cells by interacting with PDLIM1 in intracranial aneurysms.","date":"2025","source":"Frontiers in molecular neuroscience","url":"https://pubmed.ncbi.nlm.nih.gov/40881324","citation_count":0,"is_preprint":false},{"pmid":"41850063","id":"PMC_41850063","title":"Multi-omics analysis reveals RBPJ-mediated regulation of EGF/ACTN2/MYPN/COL21A1 in fibroblast during oviduct functional remodeling of duck.","date":"2026","source":"Poultry science","url":"https://pubmed.ncbi.nlm.nih.gov/41850063","citation_count":0,"is_preprint":false},{"pmid":null,"id":"bio_10.1101_2025.10.28.685214","title":"Dosage-sensitive  <i>RBFOX2</i>  autoregulation promotes cardiomyocyte differentiation by maturing the transcriptome","date":"2025-10-30","source":"bioRxiv","url":"https://doi.org/10.1101/2025.10.28.685214","citation_count":0,"is_preprint":true},{"pmid":null,"id":"bio_10.1101_2025.03.28.645933","title":"Alpha-actinin-1 stabilizes focal adhesions to facilitate sarcomere assembly in cardiac myocytes","date":"2025-03-29","source":"bioRxiv","url":"https://doi.org/10.1101/2025.03.28.645933","citation_count":0,"is_preprint":true},{"pmid":null,"id":"bio_10.1101_2025.02.18.638894","title":"A Genetic Analysis of Lipid Metabolism Regulation in Han Chinese Youth in Xinjiang via Extreme Phenotypic Strategies","date":"2025-02-23","source":"bioRxiv","url":"https://doi.org/10.1101/2025.02.18.638894","citation_count":0,"is_preprint":true},{"pmid":null,"id":"bio_10.1101_2024.11.26.625523","title":"A “non-muscle” α-actinin is an intrinsic component of the cardiac Z-disc and regulates sarcomere turnover, contractility, and heart remodeling","date":"2024-11-28","source":"bioRxiv","url":"https://doi.org/10.1101/2024.11.26.625523","citation_count":0,"is_preprint":true},{"pmid":null,"id":"bio_10.1101_2024.09.11.612512","title":"Cardiac Fibroblasts regulate myocardium and coronary vasculature development via the collagen signaling pathway","date":"2024-09-12","source":"bioRxiv","url":"https://doi.org/10.1101/2024.09.11.612512","citation_count":0,"is_preprint":true},{"pmid":null,"id":"bio_10.1101_2024.07.29.24311030","title":"Plasma Proteomic Signature of Mucolipidosis Type IV","date":"2024-07-29","source":"bioRxiv","url":"https://doi.org/10.1101/2024.07.29.24311030","citation_count":0,"is_preprint":true}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":20600,"output_tokens":3410,"usd":0.056475,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":10916,"output_tokens":3897,"usd":0.076003,"stage2_stop_reason":"end_turn"},"total_usd":0.132478,"stage1_batch_id":"msgbatch_0179Z2pxRYBsXi2xADneafRw","stage2_batch_id":"msgbatch_01LaY9ZaVdgjWArcZo9eqQE5","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2016,\n      \"finding\": \"Two HCM-associated mutations in the calponin-homology domain of ACTN2 (A119T and G111V) cause small but distinct changes in the secondary and tertiary structure of the purified actin-binding domain (ABD), reduce F-actin binding affinity, and impair Z-disc localization and dynamic behaviour of full-length mEos2-tagged protein in adult cardiomyocytes.\",\n      \"method\": \"Circular dichroism, X-ray crystallography of purified ABD; F-actin co-sedimentation assay; expression of tagged full-length protein in adult cardiomyocytes with live-cell imaging\",\n      \"journal\": \"The Biochemical journal\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — in vitro structural (X-ray crystallography) and biochemical (F-actin binding) assays combined with cellular localization experiments in a single study, multiple orthogonal methods\",\n      \"pmids\": [\"27287556\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"A pathogenic missense ACTN2 variant (c.740C>T) causes protein aggregation in hiPSC-derived cardiomyocytes, leading to activation of the ubiquitin-proteasome system and autophagy-lysosomal pathway, myofibrillar disarray, and force impairment in engineered heart tissues — defining proteopathy as a disease mechanism for ACTN2-associated cardiomyopathy.\",\n      \"method\": \"CRISPR/Cas9 heterozygous knock-in hiPSC lines; immunofluorescence, live-cell imaging, RNA-seq, mass spectrometry proteomics; engineered heart tissue contractility assays\",\n      \"journal\": \"Cells\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — multiple orthogonal methods (proteomics, live imaging, functional contractility) in isogenic CRISPR hiPSC-CM models\",\n      \"pmids\": [\"36078153\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"The ACTN2 p.Met228Thr variant destabilizes the mutant alpha-actinin-2 protein, triggering increased activity of the ubiquitin-proteasomal system; homozygous embryos show sarcomeric parameter abnormalities, cell-cycle defects, and mitochondrial dysfunction detected by unbiased proteomics, leading to embryonic lethality.\",\n      \"method\": \"Knock-in mouse model; echocardiography; High Resolution Episcopic Microscopy; unbiased proteomics; qPCR; Western blotting\",\n      \"journal\": \"Cells\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — in vivo mouse model with multiple orthogonal molecular readouts (proteomics, Western blot, morphology) in a single rigorous study\",\n      \"pmids\": [\"36899856\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"De novo missense and deletion mutations in ACTN2 cause sarcomeric disorganization and impaired muscle force in vivo. Mutant alpha-actinin-2 localizes correctly to the Z-line in differentiating myotubes; zebrafish expressing mutant ACTN2 show motor deficits and sarcomeric disorganization, and AAV-transduced mouse muscles show impaired force and Z-line/core defects, while wild-type ACTN2 expression produces no such abnormalities.\",\n      \"method\": \"Exome sequencing; muscle biopsy ultrastructure; zebrafish and AAV-mouse in vivo expression of mutant vs. wild-type ACTN2; muscle force measurement in isolated muscles; immunofluorescence in differentiating myotubes\",\n      \"journal\": \"Acta neuropathologica\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — two independent in vivo model systems (zebrafish and mouse) with functional force measurements and structural readouts, wild-type controls\",\n      \"pmids\": [\"30701273\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2026,\n      \"finding\": \"CDK1 phosphorylates ACTN2 at Thr308, and this phosphorylation regulates sarcomere assembly: CRISPR-Cas9 phospho-null (T308A) C2C12 cells differentiate rapidly and form robust sarcomeres, whereas phosphomimetic (T308D) cells fail to form organized sarcomeres, linking cell-cycle exit to sarcomere assembly via ACTN2 phosphorylation status.\",\n      \"method\": \"In vitro CDK1 kinase assay with wild-type and T308A mutant Actn2; CRISPR-Cas9 knock-in of T308A and T308D variants in C2C12 cells; immunofluorescence of sarcomere structure; proliferation assays\",\n      \"journal\": \"Physiological reports\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — in vitro kinase assay with mutagenesis validation combined with CRISPR knock-in functional cell model, multiple orthogonal readouts\",\n      \"pmids\": [\"41953953\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"Protein-extending dominant frameshift variants in ACTN2 cause alpha-actinin-2 protein aggregation in C2C12 cells, whereas missense variants associated with recessive actininopathy do not produce detectable aggregates, establishing protein aggregation as the pathomechanism specifically for dominant protein-extending frameshift actininopathies.\",\n      \"method\": \"C2C12 cell model expressing frameshift and missense ACTN2 variants; immunofluorescence for aggregate detection\",\n      \"journal\": \"Annals of clinical and translational neurology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — cell model with immunofluorescence, replicated across two publications (PMID 39095936 and preprint PMID 38293186) from same group, single method\",\n      \"pmids\": [\"39095936\", \"38293186\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"Knockdown of ACTN2 in H9c2 cardiomyocytes under chronic dexamethasone stress impairs calcium uptake and promotes hypertrophy via excessive activation of the MAPK/ERK cascade; pharmacological ERK inhibition partially reverses the hypertrophic morphology and molecular markers.\",\n      \"method\": \"siRNA knockdown of Actn2 in H9c2 cells; transcriptome analysis; Western blotting for ERK phosphorylation; ERK inhibitor rescue experiments; measurement of hypertrophic biomarkers\",\n      \"journal\": \"Genes & genomics\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Weak — clean siRNA knockdown with transcriptome + Western blot + pharmacological rescue, single lab, single cell line\",\n      \"pmids\": [\"38990270\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"Under ER stress, the transcription factor XBP1 upregulates Actn2 promoter activity in C2C12 myotubes, while XBP1, ATF4, and ATF6 downregulate Actn3 promoter activity; chemical induction of ER stress increases Actn2 mRNA and keeps α-actinin-2 protein levels unchanged, whereas α-actinin-3 protein is decreased.\",\n      \"method\": \"Promoter activity assays (reporter constructs) with UPR transcription factor overexpression; RT-qPCR; Western blotting in C2C12 myotubes under ER stress induction\",\n      \"journal\": \"Journal of muscle research and cell motility\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — promoter reporter assays combined with mRNA and protein quantification, single lab, focused on transcriptional regulation\",\n      \"pmids\": [\"32451822\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"PRDM9 promotes ACTN2 transcription through H3K4me3 histone modification; ACTN2 knockdown inhibits the Hippo pathway in vascular smooth muscle cells (VSMCs), exacerbating apoptosis and inflammation, and PDLIM1 interacts with ACTN2 to mediate VSMC function via Hippo-YAP signaling.\",\n      \"method\": \"shRNA knockdown and overexpression; ChIP-qPCR for PRDM9-H3K4me3 at ACTN2 locus; CRISPR-Cas9 PRDM9 editing; co-immunoprecipitation/interaction screening for PDLIM1; functional rescue experiments; Western blot, ELISA, immunofluorescence\",\n      \"journal\": \"Frontiers in molecular neuroscience\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Weak — ChIP-qPCR and CRISPR validation for epigenetic regulation, co-IP for interaction, functional rescue, single lab\",\n      \"pmids\": [\"40881324\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"RBFOX2 haploinsufficiency reduces ACTN2 expression in differentiating cardiomyocytes; overexpression of ACTN2 rescues contractility in RBFOX2 heterozygous but not null hiPSC-derived cardiomyocytes, and this rescue triggers a mechanosensing feedback loop that upregulates RBFOX2 from the wild-type allele and promotes transcriptome maturation.\",\n      \"method\": \"RBFOX2 heterozygous and null hiPSC-CM models; ACTN2 overexpression rescue; contractility measurements; RNA-seq; mechanosensing assays\",\n      \"journal\": \"bioRxiv\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Weak — isogenic hiPSC-CM models with functional contractility readout and rescue experiment, preprint not yet peer-reviewed\",\n      \"pmids\": [\"bio_10.1101_2025.10.28.685214\"],\n      \"is_preprint\": true\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"ACTN4 forms a heterodimeric complex with muscle-specific ACTN2 at the cardiac Z-disc, as supported by biochemical experiments and AI modeling; ACTN4 depletion from human iPSC-CMs stabilizes canonical sarcomere proteins and drives contractility-dependent hypertrophy, while ACTN4 overexpression destabilizes sarcomeres.\",\n      \"method\": \"Co-immunoprecipitation; immunofluorescence; AI structural modeling; siRNA depletion in hiPSC-CMs; contractility measurements; zebrafish loss-of-function\",\n      \"journal\": \"bioRxiv\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Weak — biochemical Co-IP plus functional depletion in two model systems, preprint not yet peer-reviewed\",\n      \"pmids\": [\"bio_10.1101_2024.11.26.625523\"],\n      \"is_preprint\": true\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"Dominant missense mutations in ACTN2 cause adult-onset distal myopathy (actininopathy), establishing ACTN2 as a skeletal muscle disease gene distinct from its known cardiac roles.\",\n      \"method\": \"Whole-exome sequencing; co-segregation analysis in 4 families; muscle biopsy histopathology\",\n      \"journal\": \"Annals of neurology\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — genetic and histopathological characterization without in vitro/in vivo mechanistic follow-up in this paper; no direct functional assay of mutant protein\",\n      \"pmids\": [\"30900782\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"ACTN2 encodes alpha-actinin-2, a Z-disc protein that crosslinks antiparallel actin filaments and links titin to the sarcomere Z-disk in cardiac and skeletal muscle; its calponin-homology ABD directly binds F-actin (HCM mutations reduce this affinity and impair Z-disc incorporation), its stability is regulated by CDK1-mediated phosphorylation at Thr308 (controlling cell-cycle-dependent sarcomere assembly), it forms a heterodimer with ACTN4 at the cardiac Z-disc, its transcription is driven by PRDM9 via H3K4me3 modification and by XBP1 under ER stress, pathogenic variants destabilize the protein and activate the ubiquitin-proteasome system (proteopathy), and protein-extending frameshift variants cause dominant disease through alpha-actinin-2 aggregation, while loss of ACTN2 function promotes cardiomyocyte hypertrophy via MAPK/ERK signaling.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"ACTN2 encodes alpha-actinin-2, a Z-disc structural protein essential for sarcomere assembly and contractile function in cardiac and skeletal muscle [#0, #3]. Its calponin-homology actin-binding domain directly engages F-actin, and HCM-associated mutations in this domain perturb its structure, reduce F-actin binding affinity, and impair Z-disc localization and dynamics in cardiomyocytes [#0]. The protein's incorporation into the sarcomere is gated by the cell cycle: CDK1 phosphorylates ACTN2 at Thr308, and phospho-null cells assemble robust sarcomeres while phosphomimetic cells fail, coupling cell-cycle exit to sarcomere maturation [#4]. A recurrent disease theme is proteostatic failure — pathogenic missense and protein-extending frameshift variants destabilize or aggregate alpha-actinin-2, activating the ubiquitin-proteasome system and autophagy-lysosomal pathway and producing myofibrillar disarray, force impairment, and in mice embryonic lethality with mitochondrial and cell-cycle defects [#1, #2, #5]. Beyond its structural role, loss of ACTN2 in stressed cardiomyocytes promotes hypertrophy through excessive MAPK/ERK activation [#6], and its expression is transcriptionally controlled by XBP1 under ER stress and by PRDM9 via H3K4me3 [#7, #8]. Dominant missense mutations in ACTN2 cause adult-onset distal myopathy (actininopathy), extending its disease spectrum beyond cardiac muscle [#11].\",\n  \"teleology\": [\n    {\n      \"year\": 2016,\n      \"claim\": \"Established at structural and biochemical resolution how disease mutations in the actin-binding domain impair ACTN2's core function — linking F-actin engagement to Z-disc integration.\",\n      \"evidence\": \"X-ray crystallography and circular dichroism of purified ABD with F-actin co-sedimentation and live-cell imaging of tagged full-length protein in adult cardiomyocytes\",\n      \"pmids\": [\"27287556\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Did not establish how reduced F-actin affinity propagates to contractile force in intact tissue\", \"Only two HCM mutations examined\"]\n    },\n    {\n      \"year\": 2019,\n      \"claim\": \"Demonstrated that ACTN2 mutations cause skeletal muscle disease in vivo, showing mutant protein localizes correctly yet still disorganizes the sarcomere and impairs force — a dominant-negative structural effect rather than simple mislocalization.\",\n      \"evidence\": \"Exome sequencing, zebrafish and AAV-mouse expression of mutant vs. wild-type ACTN2, isolated muscle force measurement, myotube immunofluorescence\",\n      \"pmids\": [\"30701273\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Molecular basis of disorganization despite correct Z-line targeting unresolved\", \"Did not define proteostatic consequences\"]\n    },\n    {\n      \"year\": 2019,\n      \"claim\": \"Defined ACTN2 as a skeletal-muscle disease gene through dominant missense mutations causing adult-onset distal myopathy, broadening its phenotype beyond cardiac roles.\",\n      \"evidence\": \"Whole-exome sequencing and co-segregation in 4 families with muscle biopsy histopathology\",\n      \"pmids\": [\"30900782\"],\n      \"confidence\": \"Low\",\n      \"gaps\": [\"No in vitro or in vivo functional assay of mutant protein in this study\", \"Mechanism connecting genotype to histopathology not established\"]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"Identified transcriptional control of ACTN2 under ER stress, showing XBP1 sustains alpha-actinin-2 levels while related ACTN3 is downregulated, distinguishing isoform-specific UPR regulation.\",\n      \"evidence\": \"Promoter reporter assays with UPR transcription factor overexpression, RT-qPCR and Western blotting in C2C12 myotubes under ER stress\",\n      \"pmids\": [\"32451822\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct XBP1 binding to the ACTN2 promoter not mapped\", \"Physiological relevance in muscle tissue untested\"]\n    },\n    {\n      \"year\": 2022,\n      \"claim\": \"Defined proteopathy as a disease mechanism — showing a pathogenic missense variant aggregates and triggers proteostatic clearance pathways with functional force loss in human cardiac tissue.\",\n      \"evidence\": \"Isogenic CRISPR knock-in hiPSC-CM lines with proteomics, live imaging, RNA-seq, and engineered heart tissue contractility\",\n      \"pmids\": [\"36078153\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Whether aggregation is cause or consequence of force loss not fully separated\", \"Single variant studied\"]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Extended the destabilization/proteostasis model in vivo, linking a destabilizing variant to UPS activation, cell-cycle and mitochondrial defects, and embryonic lethality.\",\n      \"evidence\": \"Knock-in mouse model with echocardiography, episcopic microscopy, unbiased proteomics, qPCR and Western blotting\",\n      \"pmids\": [\"36899856\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Causal hierarchy between sarcomeric, cell-cycle and mitochondrial phenotypes unresolved\", \"Mechanism connecting alpha-actinin-2 loss to mitochondrial dysfunction unknown\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Distinguished variant-class-specific pathomechanisms, showing protein-extending frameshift variants aggregate whereas recessive missense variants do not — tying aggregation specifically to dominant frameshift actininopathy.\",\n      \"evidence\": \"C2C12 cell expression of frameshift vs. missense variants with immunofluorescence aggregate detection\",\n      \"pmids\": [\"39095936\", \"38293186\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Single method (immunofluorescence) without biochemical aggregate characterization\", \"Effect on contractile function not measured\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Revealed a signaling role beyond structure: ACTN2 loss under stress drives hypertrophy via MAPK/ERK, with pharmacological ERK inhibition partially rescuing.\",\n      \"evidence\": \"siRNA knockdown in H9c2 cells with transcriptomics, Western blot for ERK phosphorylation, and ERK inhibitor rescue\",\n      \"pmids\": [\"38990270\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Mechanism linking alpha-actinin-2 to ERK activation undefined\", \"Single cell line and stress context\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Identified ACTN4 as a heterodimeric partner of ACTN2 at the cardiac Z-disc whose level tunes sarcomere stability and contractility-dependent hypertrophy.\",\n      \"evidence\": \"Co-immunoprecipitation, AI structural modeling, siRNA depletion in hiPSC-CMs, contractility, and zebrafish loss-of-function (preprint)\",\n      \"pmids\": [\"bio_10.1101_2024.11.26.625523\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Preprint, not peer-reviewed\", \"Stoichiometry and structural basis of heterodimer not biochemically resolved\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Connected ACTN2 to epigenetic regulation and Hippo signaling, with PRDM9 driving its transcription and PDLIM1 interaction mediating vascular smooth muscle function.\",\n      \"evidence\": \"ChIP-qPCR, CRISPR PRDM9 editing, co-IP for PDLIM1, and functional rescue in VSMCs\",\n      \"pmids\": [\"40881324\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Role of ACTN2 in non-muscle VSMC context not independently confirmed\", \"PDLIM1 interaction not reciprocally validated\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Placed ACTN2 within a dosage-sensitive maturation feedback loop, where RBFOX2-dependent ACTN2 levels feed back through mechanosensing to drive cardiomyocyte transcriptome maturation.\",\n      \"evidence\": \"RBFOX2 heterozygous and null hiPSC-CM models with ACTN2 overexpression rescue, contractility, RNA-seq and mechanosensing assays (preprint)\",\n      \"pmids\": [\"bio_10.1101_2025.10.28.685214\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Preprint, not peer-reviewed\", \"Molecular components of the mechanosensing feedback not defined\"]\n    },\n    {\n      \"year\": 2026,\n      \"claim\": \"Established post-translational coupling of cell-cycle exit to sarcomere assembly via CDK1 phosphorylation of ACTN2 at Thr308.\",\n      \"evidence\": \"In vitro CDK1 kinase assay with mutagenesis and CRISPR knock-in of T308A/T308D in C2C12 cells with sarcomere imaging and proliferation assays\",\n      \"pmids\": [\"41953953\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"How phosphorylation alters ACTN2 binding or localization mechanistically unresolved\", \"In vivo relevance in developing heart untested\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How the distinct disease mechanisms (impaired actin binding, protein aggregation/proteostatic failure, and altered signaling) are integrated, and what determines the cardiac versus skeletal phenotype of a given variant, remains unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No unified model linking variant class to tissue-specific outcome\", \"Structural basis of Thr308 phosphoregulation undefined\", \"Mechanism of ACTN2-dependent ERK and Hippo signaling unknown\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0008092\", \"supporting_discovery_ids\": [0, 3]},\n      {\"term_id\": \"GO:0005198\", \"supporting_discovery_ids\": [0, 3]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005856\", \"supporting_discovery_ids\": [0, 3, 10]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-397014\", \"supporting_discovery_ids\": [0, 3, 4]},\n      {\"term_id\": \"R-HSA-392499\", \"supporting_discovery_ids\": [1, 2]}\n    ],\n    \"complexes\": [\"cardiac Z-disc\"],\n    \"partners\": [\"ACTN4\", \"PDLIM1\"],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":6,"faith_total":6,"faith_pct":100.0}}