{"gene":"FMNL1","run_date":"2026-06-09T23:54:44","timeline":{"discoveries":[{"year":2009,"finding":"FMNL1 membrane localization and cortical targeting is regulated by N-terminal myristoylation; a splice variant (FMNL1γ) with intron retention at the C-terminus affecting the diaphanous autoinhibitory domain (DAD) constitutively localizes to the cell membrane and cortex, mimicking a DAD-deletion mutant. Both FMNL1γ and FMNL1ΔDAD induce polarized non-apoptotic membrane blebbing dependent on N-myristoylation but independent of Src and ROCK activity.","method":"Site-directed mutagenesis, live-cell fluorescence microscopy, pharmacological inhibition (Src inhibitor, ROCK inhibitor), N-myristoylation mutant analysis, splice variant characterization","journal":"The Journal of biological chemistry","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — multiple orthogonal methods (mutagenesis, pharmacological inhibition, live imaging) in a single lab; mechanistic claims are well-supported within one study","pmids":["19815554"],"is_preprint":false},{"year":2010,"finding":"FMNL1 (FRL1) localizes to the actin-rich cores of primary macrophage podosomes, co-precipitates with β3 integrin, and is required for podosome dynamics and cell adhesion; siRNA-mediated knockdown disrupts podosome integrity and reduces cell adhesion.","method":"siRNA knockdown, co-immunoprecipitation with β3 integrin, fixed and live-cell fluorescence microscopy, Western blotting, quantitative RT-PCR","journal":"Cytoskeleton (Hoboken, N.J.)","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — reciprocal Co-IP, live-cell imaging, and KD phenotype in single lab with multiple orthogonal methods","pmids":["20617518"],"is_preprint":false},{"year":2012,"finding":"FMNL1 interacts with the giant scaffolding protein AHNAK1; the N-terminal part of FMNL1 binds the C-terminus of AHNAK1. Constitutively active FMNL1γ induces relocalization of AHNAK1 to the cell membrane. FMNL1 overexpression or knockdown modulates capacitative calcium influx following ionomycin stimulation.","method":"Proteomic interactome screen (MS), co-immunoprecipitation, domain-mapping pulldown, live-cell imaging, calcium influx assay","journal":"Journal of proteomics","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — MS interactome confirmed by Co-IP and domain mapping in single lab; calcium function supported by OE/KD experiments","pmids":["23182705"],"is_preprint":false},{"year":2013,"finding":"FMNL1 endogenously associates with Rac1 in leukemia cells; FMNL1 silencing paradoxically increases Rac1 activity, and the reduced migration of FMNL1-depleted cells is rescued by Rac1 inhibition, placing FMNL1 upstream of Rac1 as a negative regulator of Rac1 activity in this context.","method":"Co-immunoprecipitation, siRNA knockdown, Rac1 activity assay (pull-down), pharmacological Rac1 inhibition rescue experiment, transwell migration assay","journal":"Journal of leukocyte biology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — reciprocal Co-IP, activity assay, and pharmacological rescue in single lab with multiple orthogonal methods","pmids":["23801653"],"is_preprint":false},{"year":2013,"finding":"FMNL1 and mDia1 are specifically enriched at macrophage pseudopods contacting Borrelia burgdorferi spirochetes; siRNA-mediated knockdown of FMNL1 or mDia1 decreases pseudopod formation and reduces internalization of borreliae, establishing FMNL1 as a required actin regulatory factor for coiling phagocytosis.","method":"Immunofluorescence, live-cell imaging, ratiometric analysis of formin enrichment, siRNA knockdown, quantification of Borrelia internalization","journal":"Infection and immunity","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — live imaging plus KD phenotype with quantitative internalization readout in a single study; two orthogonal approaches","pmids":["23460512"],"is_preprint":false},{"year":2014,"finding":"In mouse oocytes, FMNL1 acts upstream of mDia1 in a FMNL1–mDia1–Profilin1 signaling pathway: FMNL1 knockdown reduces mDia1 expression whereas RhoA inhibition does not alter mDia1 levels, placing FMNL1 between RhoA and mDia1 for actin assembly and spindle organization during meiosis.","method":"Morpholino knockdown, immunofluorescence, Western blotting, RhoA inhibitor treatment, epistasis analysis","journal":"Biochimica et biophysica acta","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — genetic epistasis via morpholino KD and pharmacological inhibition in single lab with pathway ordering supported by protein level changes","pmids":["25447542"],"is_preprint":false},{"year":2015,"finding":"In mouse oocytes, FMNL1 localizes to spindle poles after germinal vesicle breakdown; FMNL1 knockdown causes aberrant actin expression, loss of cortical actin cap and cortical granule-free domain, failure of meiotic spindle positioning, disrupted p-MAPK localization, and aberrant GM130 (cis-Golgi) distribution. RhoA acts as an upstream regulator of FMNL1 in oocyte meiosis.","method":"Morpholino microinjection, live-cell time-lapse imaging, immunofluorescence, epistasis with RhoA inhibition","journal":"Cell cycle (Georgetown, Tex.)","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — morpholino KD with multiple phenotypic readouts and upstream regulator identification; single lab, multiple orthogonal readouts","pmids":["26083584"],"is_preprint":false},{"year":2015,"finding":"FMNL1 is required for normal podosome dynamics and macrophage migration; pharmacological inhibition of all formins reduces podosome formation, and targeted FMNL1 siRNA suppression reduces macrophage migration to a similar extent, demonstrating FMNL1 as the dominant formin driving podosome-based macrophage migration.","method":"siRNA knockdown, pharmacological formin inhibition (SMIFH2), migration assays, podosome quantification in primary human macrophages","journal":"CellBio","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — KD and pharmacological inhibition with defined migratory phenotype in primary human cells; single lab","pmids":["26942206"],"is_preprint":false},{"year":2018,"finding":"FMNL1 promotes NPC cell aggressiveness by increasing MTA1 transcription through an epigenetic mechanism: FMNL1 overexpression enhances binding of HDAC1 with Profilin2 in the cytoplasm, sequestering HDAC1 away from the MTA1 promoter, thereby de-repressing MTA1 expression.","method":"Co-immunoprecipitation (HDAC1–Profilin2 interaction), chromatin immunoprecipitation (ChIP) at MTA1 promoter, ectopic overexpression and siRNA knockdown, in vitro/in vivo invasion assays","journal":"Oncogene","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — ChIP and Co-IP with functional rescue; single lab with two orthogonal mechanistic methods","pmids":["30013189"],"is_preprint":false},{"year":2019,"finding":"FMNL1γ isoform, but not FMNL1α or FMNL1β, bundles filamentous actin independently of the FH2 domain in vitro; while FMNL1γ inhibits actin assembly in vitro, it enhances cell adhesion and rescues migration in FMNL1-depleted breast adenocarcinoma cells. The three isoforms exhibit distinct subcellular localizations.","method":"In vitro actin assembly and bundling assay, isoform overexpression and siRNA rescue, cell adhesion and migration assays, fluorescence microscopy for localization","journal":"Journal of cellular biochemistry","confidence":"Medium","confidence_rationale":"Tier 1–2 / Moderate — in vitro actin bundling assay with domain mutant plus cellular rescue experiments; single lab","pmids":["30977161"],"is_preprint":false},{"year":2020,"finding":"FMNL1 promotes ccRCC cell migration in vitro and tumor metastasis in vivo via transcriptional induction of CXCR2; FMNL1 increases CXCR2 expression through HDAC1, and knockdown of CXCR2 markedly attenuates FMNL1-enhanced cell motility. FMNL1 upregulation in ccRCC is mediated by loss of the transcription factor GATA3.","method":"ChIP, luciferase reporter assay, siRNA knockdown, ectopic overexpression, in vivo xenograft metastasis model, rescue experiments with CXCR2 knockdown","journal":"Frontiers in oncology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — ChIP and luciferase reporter confirm HDAC1/CXCR2 regulation; in vivo rescue data; single lab","pmids":["33324547"],"is_preprint":false},{"year":2020,"finding":"In Drosophila epithelial cells, the FMNL1 ortholog Frl/Fmnl nucleates a persistent, homogeneous F-actin subpopulation at the medioapical cortex independently of Rho1; loss of Frl reduces network density and impairs homogeneous force transmission, causing tissue-scale morphogenetic defects, while overexpression increases network density.","method":"Drosophila genetic mutants, live-cell imaging, quantitative image analysis, F-actin network characterization","journal":"Nature cell biology","confidence":"High","confidence_rationale":"Tier 2 / Strong — rigorous genetic loss- and gain-of-function in an in vivo model (Drosophila ortholog), replicated across multiple conditions with quantitative mechanistic readouts published in high-impact journal","pmids":["32483386"],"is_preprint":false},{"year":2024,"finding":"In T cells, FMNL1 localizes predominantly to the rear of migrating cells and a portion physically associates with the nucleus; FMNL1 promotes efficient migration specifically in confined 3D environments by facilitating deformation of the rigid T cell nucleus, a mechanism distinct from mDia1 which promotes general motility in 3D via Myosin-II activity.","method":"In vivo T cell migration analysis, in vitro 2D and 3D migration assays, subcellular fractionation and nuclear association, FMNL1/mDia1 knockout comparison, Myosin-II inhibition","journal":"Frontiers in immunology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — in vivo plus in vitro 3D assays with nuclear localization and functional epistasis; single lab with multiple orthogonal approaches","pmids":["39430739"],"is_preprint":false},{"year":2024,"finding":"Rab25-positive recycling endosomes coordinate positioning of FMNL1 and integrin β1 to the cell periphery together with Rho GTPase activation at the plasma membrane to generate and maintain F-actin-rich filopodial protrusions and promote cancer cell invasive migration in 3D matrix; direct magnetic manipulation of Rab25 vesicles to the cell periphery drives F-actin protrusion formation.","method":"Magnetogenetic manipulation of Rab25 vesicle positioning, live-cell imaging, Rho GTPase activation readout, F-actin protrusion quantification in 3D matrix","journal":"bioRxiv (preprint)","confidence":"Low","confidence_rationale":"Tier 3 / Weak — novel magnetogenetic approach but preprint, single lab, and FMNL1 is one of several cargoes with no direct functional dissection of FMNL1 specifically","pmids":[],"is_preprint":true}],"current_model":"FMNL1 is an N-myristoylated formin-family actin nucleator/bundler predominantly expressed in hematopoietic cells that localizes to the cell membrane/cortex (regulated by autoinhibition via its DAD domain), podosomes, and the rear of migrating T cells, where it drives actin assembly for podosome dynamics, phagocytosis, lamellipodial protrusion, and nuclear deformation in confined environments; it acts downstream of RhoA, associates with β3 integrin and AHNAK1, negatively regulates Rac1 activity, epigenetically upregulates MTA1 and CXCR2 via cytoplasmic sequestration of HDAC1, and in oocyte meiosis operates in a RhoA–FMNL1–mDia1–Profilin1 pathway to coordinate actin cortex polarity and spindle organization."},"narrative":{"mechanistic_narrative":"FMNL1 is a formin-family actin nucleator and bundler that drives cortical and protrusive actin assembly across hematopoietic, epithelial, and tumor cells [PMID:20617518, PMID:30977161, PMID:32483386]. Its activity is gated by autoinhibition through the diaphanous autoinhibitory domain (DAD): a C-terminally truncated splice variant (FMNL1γ) or DAD deletion relieves this control and constitutively targets the protein to the membrane and cortex in an N-myristoylation–dependent manner, where it induces polarized membrane blebbing [PMID:19815554]. The three isoforms localize distinctly, and FMNL1γ bundles F-actin independently of its FH2 domain while supporting cell adhesion and migration [PMID:30977161]. At the cell cortex FMNL1 localizes to macrophage podosome cores, co-precipitates with β3 integrin, and is the dominant formin sustaining podosome dynamics, adhesion, and macrophage migration [PMID:20617518, PMID:26942206]; it also drives pseudopod-based coiling phagocytosis of Borrelia together with mDia1 [PMID:23460512]. FMNL1 operates within Rho GTPase circuitry: it acts downstream of RhoA in a RhoA–FMNL1–mDia1–Profilin1 pathway organizing the actin cortex and meiotic spindle in oocytes [PMID:25447542, PMID:26083584], and it negatively regulates Rac1 activity to control leukemia cell migration [PMID:23801653]. In migrating T cells FMNL1 concentrates at the cell rear and physically associates with the nucleus, enabling deformation of the rigid nucleus for migration through confined 3D environments [PMID:39430739]. Beyond its cytoskeletal roles, FMNL1 promotes tumor aggressiveness through an indirect epigenetic mechanism, sequestering HDAC1 in the cytoplasm to de-repress transcription of MTA1 and CXCR2 [PMID:30013189, PMID:33324547]. It additionally binds the scaffold AHNAK1 and modulates capacitative calcium influx [PMID:23182705].","teleology":[{"year":2009,"claim":"Established how FMNL1 is targeted to the membrane and de-repressed, defining N-myristoylation and DAD-mediated autoinhibition as the switches controlling its cortical activity.","evidence":"Site-directed mutagenesis, splice-variant characterization, pharmacological inhibition, and live-cell imaging","pmids":["19815554"],"confidence":"Medium","gaps":["Did not identify the physiological signal that relieves DAD autoinhibition in vivo","Functional consequence of blebbing for cell behavior unresolved"]},{"year":2010,"claim":"Placed FMNL1 at adhesive actin structures by showing it occupies podosome cores, binds β3 integrin, and is required for podosome integrity and adhesion.","evidence":"siRNA knockdown, Co-IP with β3 integrin, and live/fixed imaging in primary macrophages","pmids":["20617518"],"confidence":"Medium","gaps":["Whether β3 integrin association is direct not established","Did not test actin nucleation activity at podosomes directly"]},{"year":2012,"claim":"Identified AHNAK1 as a direct FMNL1 partner and linked FMNL1 to calcium influx, extending its role beyond cytoskeletal scaffolding.","evidence":"MS interactome, Co-IP, domain-mapping pulldown, and calcium influx assays","pmids":["23182705"],"confidence":"Medium","gaps":["Mechanism connecting FMNL1/AHNAK1 to calcium entry unresolved","Physiological context of the interaction unclear"]},{"year":2013,"claim":"Defined FMNL1 as a negative regulator of Rac1, an unexpected role for a formin, with consequences for leukemia cell migration.","evidence":"Co-IP, Rac1 activity pull-down, and pharmacological Rac1-inhibition rescue of migration","pmids":["23801653"],"confidence":"Medium","gaps":["Molecular basis for suppression of Rac1 activity not established","Generality beyond leukemia cells untested"]},{"year":2013,"claim":"Showed FMNL1 is a required actin factor for coiling phagocytosis, acting alongside mDia1 at pathogen-contacting pseudopods.","evidence":"Immunofluorescence, ratiometric enrichment analysis, siRNA knockdown, and Borrelia internalization quantification","pmids":["23460512"],"confidence":"Medium","gaps":["Division of labor between FMNL1 and mDia1 not dissected","Upstream receptor signaling not identified"]},{"year":2015,"claim":"Positioned FMNL1 within a RhoA–FMNL1–mDia1–Profilin1 pathway and at spindle poles, linking it to actin cortex polarity and meiotic spindle organization.","evidence":"Morpholino knockdown, immunofluorescence, Western blotting, and RhoA-inhibitor epistasis in mouse oocytes","pmids":["25447542","26083584"],"confidence":"Medium","gaps":["Mechanism by which FMNL1 controls mDia1 protein levels unknown","How spindle-pole localization is established not resolved"]},{"year":2015,"claim":"Demonstrated FMNL1 is the dominant formin driving podosome-based macrophage migration, distinguishing its contribution from other formins.","evidence":"siRNA knockdown, SMIFH2 pan-formin inhibition, and migration/podosome quantification in primary human macrophages","pmids":["26942206"],"confidence":"Medium","gaps":["Did not resolve which actin assembly step FMNL1 catalyzes at podosomes","Upstream activation in macrophages untested"]},{"year":2018,"claim":"Revealed a non-cytoskeletal, epigenetic mechanism whereby FMNL1 sequesters HDAC1 in the cytoplasm via Profilin2 to de-repress MTA1 and promote tumor aggressiveness.","evidence":"Co-IP, ChIP at the MTA1 promoter, overexpression/knockdown, and invasion assays in NPC cells","pmids":["30013189"],"confidence":"Medium","gaps":["Whether cytoplasmic HDAC1 sequestration depends on actin activity not addressed","Direct FMNL1–HDAC1 versus indirect interaction unresolved"]},{"year":2019,"claim":"Distinguished isoform-specific biochemistry, showing FMNL1γ bundles actin independently of its FH2 domain while inhibiting assembly yet enhancing adhesion and migration.","evidence":"In vitro actin assembly/bundling assays with domain mutants plus isoform rescue in breast adenocarcinoma cells","pmids":["30977161"],"confidence":"Medium","gaps":["Structural basis of FH2-independent bundling not defined","How opposing in vitro and cellular effects reconcile unclear"]},{"year":2020,"claim":"Extended the HDAC1-based epigenetic axis to CXCR2 and identified GATA3 loss as the driver of FMNL1 upregulation in ccRCC metastasis.","evidence":"ChIP, luciferase reporter, knockdown/overexpression, and in vivo xenograft metastasis with CXCR2-knockdown rescue","pmids":["33324547"],"confidence":"Medium","gaps":["Mechanism of GATA3 repression of FMNL1 not detailed","Generality of the HDAC1 sequestration model across tumor types untested"]},{"year":2020,"claim":"Provided rigorous in vivo evidence that the FMNL1 ortholog nucleates a homogeneous medioapical F-actin network independent of Rho1, required for tissue-scale force transmission.","evidence":"Drosophila loss- and gain-of-function genetics with quantitative F-actin network imaging","pmids":["32483386"],"confidence":"High","gaps":["Direct extrapolation to mammalian FMNL1 regulation not shown","Activating input for Rho1-independent nucleation unknown"]},{"year":2024,"claim":"Identified a confinement-specific function: rear-localized, nucleus-associated FMNL1 deforms the rigid T cell nucleus to enable migration through tight 3D spaces, mechanistically distinct from mDia1.","evidence":"In vivo and in vitro 2D/3D migration assays, subcellular fractionation, FMNL1/mDia1 knockout comparison, and Myosin-II inhibition","pmids":["39430739"],"confidence":"Medium","gaps":["How FMNL1 physically engages the nuclear envelope not defined","Whether nuclear association is direct unresolved"]},{"year":2024,"claim":"Proposed that Rab25 recycling endosomes co-deliver FMNL1 and integrin β1 to the periphery to generate filopodial protrusions during invasive migration.","evidence":"Magnetogenetic manipulation of Rab25 vesicles with F-actin protrusion quantification in 3D matrix (preprint)","pmids":[],"confidence":"Low","gaps":["Preprint not peer-reviewed; FMNL1 is one of several cargoes with no FMNL1-specific functional dissection","Whether FMNL1 is required for the protrusions unaddressed"]},{"year":null,"claim":"The signals that relieve FMNL1 autoinhibition in physiological contexts and how a single nucleator switches between cortical, podosomal, nuclear-deforming, and transcription-modulating roles remain unresolved.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No structural model of activation in mammalian cells","Context-specific partner requirements not mapped","Relationship between actin activity and the HDAC1 epigenetic role unknown"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0008092","term_label":"cytoskeletal protein binding","supporting_discovery_ids":[9,1,11]},{"term_id":"GO:0098772","term_label":"molecular function regulator activity","supporting_discovery_ids":[3,5]}],"localization":[{"term_id":"GO:0005886","term_label":"plasma membrane","supporting_discovery_ids":[0,1]},{"term_id":"GO:0005856","term_label":"cytoskeleton","supporting_discovery_ids":[1,11]},{"term_id":"GO:0005829","term_label":"cytosol","supporting_discovery_ids":[8]},{"term_id":"GO:0005815","term_label":"microtubule organizing center","supporting_discovery_ids":[6]}],"pathway":[{"term_id":"R-HSA-168256","term_label":"Immune System","supporting_discovery_ids":[1,4,12]},{"term_id":"R-HSA-1643685","term_label":"Disease","supporting_discovery_ids":[8,10]}],"complexes":[],"partners":["ITGB3","AHNAK1","RAC1","DIAPH1","HDAC1","PFN2"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"O95466","full_name":"Formin-like protein 1","aliases":["CLL-associated antigen KW-13","Leukocyte formin"],"length_aa":1100,"mass_kda":121.9,"function":"May play a role in the control of cell motility and survival of macrophages (By similarity). Plays a role in the regulation of cell morphology and cytoskeletal organization. Required in the cortical actin filament dynamics and cell shape","subcellular_location":"Cytoplasm, cell cortex; Cell projection, bleb","url":"https://www.uniprot.org/uniprotkb/O95466/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/FMNL1","classification":"Not Classified","n_dependent_lines":24,"n_total_lines":1208,"dependency_fraction":0.019867549668874173},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[],"url":"https://opencell.sf.czbiohub.org/search/FMNL1","total_profiled":1310},"omim":[{"mim_id":"616288","title":"FORMIN-LIKE 3; FMNL3","url":"https://www.omim.org/entry/616288"},{"mim_id":"616285","title":"FORMIN-LIKE 2; FMNL2","url":"https://www.omim.org/entry/616285"},{"mim_id":"604656","title":"FORMIN-LIKE 1; FMNL1","url":"https://www.omim.org/entry/604656"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Approved","locations":[{"location":"Cytosol","reliability":"Approved"}],"tissue_specificity":"Tissue enhanced","tissue_distribution":"Detected in all","driving_tissues":[{"tissue":"bone marrow","ntpm":255.3},{"tissue":"lymphoid tissue","ntpm":101.4}],"url":"https://www.proteinatlas.org/search/FMNL1"},"hgnc":{"alias_symbol":["C17orf1"],"prev_symbol":["C17orf1B","FMNL"]},"alphafold":{"accession":"O95466","domains":[{"cath_id":"-","chopping":"76-95_107-166_204-251","consensus_level":"medium","plddt":79.2721,"start":76,"end":251},{"cath_id":"1.25.10.10","chopping":"265-383","consensus_level":"medium","plddt":91.3052,"start":265,"end":383},{"cath_id":"-","chopping":"716-795","consensus_level":"medium","plddt":88.8932,"start":716,"end":795},{"cath_id":"1.20.58.2220","chopping":"834-901_990-1015","consensus_level":"medium","plddt":89.0124,"start":834,"end":1015},{"cath_id":"1.10.20","chopping":"33-74","consensus_level":"high","plddt":83.0417,"start":33,"end":74},{"cath_id":"1.20.5","chopping":"387-441","consensus_level":"medium","plddt":87.8327,"start":387,"end":441}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/O95466","model_url":"https://alphafold.ebi.ac.uk/files/AF-O95466-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-O95466-F1-predicted_aligned_error_v6.png","plddt_mean":73.88},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=FMNL1","jax_strain_url":"https://www.jax.org/strain/search?query=FMNL1"},"sequence":{"accession":"O95466","fasta_url":"https://rest.uniprot.org/uniprotkb/O95466.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/O95466/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/O95466"}},"corpus_meta":[{"pmid":"12684686","id":"PMC_12684686","title":"Identification and characterization of human FMNL1, FMNL2 and FMNL3 genes in silico.","date":"2003","source":"International journal of oncology","url":"https://pubmed.ncbi.nlm.nih.gov/12684686","citation_count":128,"is_preprint":false},{"pmid":"28327544","id":"PMC_28327544","title":"FMNL formins boost lamellipodial force generation.","date":"2017","source":"Nature communications","url":"https://pubmed.ncbi.nlm.nih.gov/28327544","citation_count":112,"is_preprint":false},{"pmid":"20617518","id":"PMC_20617518","title":"The formin FRL1 (FMNL1) is an essential component of macrophage podosomes.","date":"2010","source":"Cytoskeleton (Hoboken, N.J.)","url":"https://pubmed.ncbi.nlm.nih.gov/20617518","citation_count":74,"is_preprint":false},{"pmid":"19815554","id":"PMC_19815554","title":"Formin-like 1 (FMNL1) is regulated by N-terminal myristoylation and induces polarized membrane blebbing.","date":"2009","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/19815554","citation_count":59,"is_preprint":false},{"pmid":"23460512","id":"PMC_23460512","title":"The formins FMNL1 and mDia1 regulate coiling phagocytosis of Borrelia burgdorferi by primary human macrophages.","date":"2013","source":"Infection and immunity","url":"https://pubmed.ncbi.nlm.nih.gov/23460512","citation_count":45,"is_preprint":false},{"pmid":"23801653","id":"PMC_23801653","title":"FMNL1 promotes proliferation and migration of leukemia cells.","date":"2013","source":"Journal of leukocyte biology","url":"https://pubmed.ncbi.nlm.nih.gov/23801653","citation_count":44,"is_preprint":false},{"pmid":"23182705","id":"PMC_23182705","title":"Proteomic investigation of the interactome of FMNL1 in hematopoietic cells unveils a role in calcium-dependent membrane plasticity.","date":"2012","source":"Journal of proteomics","url":"https://pubmed.ncbi.nlm.nih.gov/23182705","citation_count":41,"is_preprint":false},{"pmid":"17626842","id":"PMC_17626842","title":"Allorestricted T cells with specificity for the FMNL1-derived peptide PP2 have potent antitumor activity against hematologic and other malignancies.","date":"2007","source":"Blood","url":"https://pubmed.ncbi.nlm.nih.gov/17626842","citation_count":40,"is_preprint":false},{"pmid":"31387165","id":"PMC_31387165","title":"FMNL1 down-regulation suppresses bone metastasis through reducing TGF-β1 expression in non-small cell lung cancer (NSCLC).","date":"2019","source":"Biomedicine & pharmacotherapy = Biomedecine & pharmacotherapie","url":"https://pubmed.ncbi.nlm.nih.gov/31387165","citation_count":34,"is_preprint":false},{"pmid":"26083584","id":"PMC_26083584","title":"RhoA-mediated FMNL1 regulates GM130 for actin assembly and phosphorylates MAPK for spindle formation in mouse oocyte meiosis.","date":"2015","source":"Cell cycle (Georgetown, Tex.)","url":"https://pubmed.ncbi.nlm.nih.gov/26083584","citation_count":32,"is_preprint":false},{"pmid":"32483386","id":"PMC_32483386","title":"Assembly of a persistent apical actin network by the formin Frl/Fmnl tunes epithelial cell deformability.","date":"2020","source":"Nature cell biology","url":"https://pubmed.ncbi.nlm.nih.gov/32483386","citation_count":31,"is_preprint":false},{"pmid":"16494944","id":"PMC_16494944","title":"High expression of FMNL1 protein in T non-Hodgkin's lymphomas.","date":"2006","source":"Leukemia research","url":"https://pubmed.ncbi.nlm.nih.gov/16494944","citation_count":30,"is_preprint":false},{"pmid":"30013189","id":"PMC_30013189","title":"FMNL1 mediates nasopharyngeal carcinoma cell aggressiveness by epigenetically upregulating MTA1.","date":"2018","source":"Oncogene","url":"https://pubmed.ncbi.nlm.nih.gov/30013189","citation_count":28,"is_preprint":false},{"pmid":"24700756","id":"PMC_24700756","title":"Characterization of Leukocyte Formin FMNL1 Expression in Human Tissues.","date":"2014","source":"The journal of histochemistry and cytochemistry : official journal of the Histochemistry Society","url":"https://pubmed.ncbi.nlm.nih.gov/24700756","citation_count":26,"is_preprint":false},{"pmid":"25447542","id":"PMC_25447542","title":"Formin mDia1, a downstream molecule of FMNL1, regulates Profilin1 for actin assembly and spindle organization during mouse oocyte meiosis.","date":"2014","source":"Biochimica et biophysica acta","url":"https://pubmed.ncbi.nlm.nih.gov/25447542","citation_count":25,"is_preprint":false},{"pmid":"26942206","id":"PMC_26942206","title":"Human Macrophages Utilize the Podosome Formin FMNL1 for Adhesion and Migration.","date":"2015","source":"CellBio","url":"https://pubmed.ncbi.nlm.nih.gov/26942206","citation_count":14,"is_preprint":false},{"pmid":"33324547","id":"PMC_33324547","title":"FMNL1 Exhibits Pro-Metastatic Activity via CXCR2 in Clear Cell Renal Cell Carcinoma.","date":"2020","source":"Frontiers in 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reports","url":"https://pubmed.ncbi.nlm.nih.gov/35953506","citation_count":5,"is_preprint":false},{"pmid":"34115237","id":"PMC_34115237","title":"FHOD1 and FMNL1 formin proteins in intestinal gastric cancer: correlation with tumor-infiltrating T lymphocytes and molecular subtypes.","date":"2021","source":"Gastric cancer : official journal of the International Gastric Cancer Association and the Japanese Gastric Cancer Association","url":"https://pubmed.ncbi.nlm.nih.gov/34115237","citation_count":5,"is_preprint":false},{"pmid":"37859818","id":"PMC_37859818","title":"Formin protein FMNL1 is a biomarker for tumor-infiltrating immune cells and associated with well immunotherapeutic response.","date":"2023","source":"Journal of Cancer","url":"https://pubmed.ncbi.nlm.nih.gov/37859818","citation_count":4,"is_preprint":false},{"pmid":"29283461","id":"PMC_29283461","title":"A pathway-based association analysis identified FMNL1-MAP3K14 as susceptibility genes for leprosy.","date":"2018","source":"Experimental dermatology","url":"https://pubmed.ncbi.nlm.nih.gov/29283461","citation_count":3,"is_preprint":false},{"pmid":"39430739","id":"PMC_39430739","title":"FMNL1 and mDia1 promote efficient T cell migration through complex environments via distinct mechanisms.","date":"2024","source":"Frontiers in immunology","url":"https://pubmed.ncbi.nlm.nih.gov/39430739","citation_count":1,"is_preprint":false},{"pmid":"40864802","id":"PMC_40864802","title":"Biochemical Changes in Prostate Cancer: FMNL1 and PAK1 in Plasma and Urine.","date":"2025","source":"Current issues in molecular biology","url":"https://pubmed.ncbi.nlm.nih.gov/40864802","citation_count":0,"is_preprint":false},{"pmid":"39697714","id":"PMC_39697714","title":"Emerging functions of FMNL1 in myeloid neoplasms: insights from bioinformatics to biological and pharmacological landscapes.","date":"2024","source":"Translational cancer 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migration","date":"2024-11-11","source":"bioRxiv","url":"https://doi.org/10.1101/2024.11.11.622870","citation_count":0,"is_preprint":true}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":15501,"output_tokens":3810,"usd":0.051826,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":11517,"output_tokens":4195,"usd":0.08123,"stage2_stop_reason":"end_turn"},"total_usd":0.133056,"stage1_batch_id":"msgbatch_01AsR7g8dGTEiEw9U83bJeWn","stage2_batch_id":"msgbatch_01YV5ZyxtFNUZEjxRcpd9jzb","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2009,\n      \"finding\": \"FMNL1 membrane localization and cortical targeting is regulated by N-terminal myristoylation; a splice variant (FMNL1γ) with intron retention at the C-terminus affecting the diaphanous autoinhibitory domain (DAD) constitutively localizes to the cell membrane and cortex, mimicking a DAD-deletion mutant. Both FMNL1γ and FMNL1ΔDAD induce polarized non-apoptotic membrane blebbing dependent on N-myristoylation but independent of Src and ROCK activity.\",\n      \"method\": \"Site-directed mutagenesis, live-cell fluorescence microscopy, pharmacological inhibition (Src inhibitor, ROCK inhibitor), N-myristoylation mutant analysis, splice variant characterization\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — multiple orthogonal methods (mutagenesis, pharmacological inhibition, live imaging) in a single lab; mechanistic claims are well-supported within one study\",\n      \"pmids\": [\"19815554\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"FMNL1 (FRL1) localizes to the actin-rich cores of primary macrophage podosomes, co-precipitates with β3 integrin, and is required for podosome dynamics and cell adhesion; siRNA-mediated knockdown disrupts podosome integrity and reduces cell adhesion.\",\n      \"method\": \"siRNA knockdown, co-immunoprecipitation with β3 integrin, fixed and live-cell fluorescence microscopy, Western blotting, quantitative RT-PCR\",\n      \"journal\": \"Cytoskeleton (Hoboken, N.J.)\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reciprocal Co-IP, live-cell imaging, and KD phenotype in single lab with multiple orthogonal methods\",\n      \"pmids\": [\"20617518\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"FMNL1 interacts with the giant scaffolding protein AHNAK1; the N-terminal part of FMNL1 binds the C-terminus of AHNAK1. Constitutively active FMNL1γ induces relocalization of AHNAK1 to the cell membrane. FMNL1 overexpression or knockdown modulates capacitative calcium influx following ionomycin stimulation.\",\n      \"method\": \"Proteomic interactome screen (MS), co-immunoprecipitation, domain-mapping pulldown, live-cell imaging, calcium influx assay\",\n      \"journal\": \"Journal of proteomics\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — MS interactome confirmed by Co-IP and domain mapping in single lab; calcium function supported by OE/KD experiments\",\n      \"pmids\": [\"23182705\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"FMNL1 endogenously associates with Rac1 in leukemia cells; FMNL1 silencing paradoxically increases Rac1 activity, and the reduced migration of FMNL1-depleted cells is rescued by Rac1 inhibition, placing FMNL1 upstream of Rac1 as a negative regulator of Rac1 activity in this context.\",\n      \"method\": \"Co-immunoprecipitation, siRNA knockdown, Rac1 activity assay (pull-down), pharmacological Rac1 inhibition rescue experiment, transwell migration assay\",\n      \"journal\": \"Journal of leukocyte biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reciprocal Co-IP, activity assay, and pharmacological rescue in single lab with multiple orthogonal methods\",\n      \"pmids\": [\"23801653\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"FMNL1 and mDia1 are specifically enriched at macrophage pseudopods contacting Borrelia burgdorferi spirochetes; siRNA-mediated knockdown of FMNL1 or mDia1 decreases pseudopod formation and reduces internalization of borreliae, establishing FMNL1 as a required actin regulatory factor for coiling phagocytosis.\",\n      \"method\": \"Immunofluorescence, live-cell imaging, ratiometric analysis of formin enrichment, siRNA knockdown, quantification of Borrelia internalization\",\n      \"journal\": \"Infection and immunity\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — live imaging plus KD phenotype with quantitative internalization readout in a single study; two orthogonal approaches\",\n      \"pmids\": [\"23460512\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"In mouse oocytes, FMNL1 acts upstream of mDia1 in a FMNL1–mDia1–Profilin1 signaling pathway: FMNL1 knockdown reduces mDia1 expression whereas RhoA inhibition does not alter mDia1 levels, placing FMNL1 between RhoA and mDia1 for actin assembly and spindle organization during meiosis.\",\n      \"method\": \"Morpholino knockdown, immunofluorescence, Western blotting, RhoA inhibitor treatment, epistasis analysis\",\n      \"journal\": \"Biochimica et biophysica acta\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genetic epistasis via morpholino KD and pharmacological inhibition in single lab with pathway ordering supported by protein level changes\",\n      \"pmids\": [\"25447542\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"In mouse oocytes, FMNL1 localizes to spindle poles after germinal vesicle breakdown; FMNL1 knockdown causes aberrant actin expression, loss of cortical actin cap and cortical granule-free domain, failure of meiotic spindle positioning, disrupted p-MAPK localization, and aberrant GM130 (cis-Golgi) distribution. RhoA acts as an upstream regulator of FMNL1 in oocyte meiosis.\",\n      \"method\": \"Morpholino microinjection, live-cell time-lapse imaging, immunofluorescence, epistasis with RhoA inhibition\",\n      \"journal\": \"Cell cycle (Georgetown, Tex.)\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — morpholino KD with multiple phenotypic readouts and upstream regulator identification; single lab, multiple orthogonal readouts\",\n      \"pmids\": [\"26083584\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"FMNL1 is required for normal podosome dynamics and macrophage migration; pharmacological inhibition of all formins reduces podosome formation, and targeted FMNL1 siRNA suppression reduces macrophage migration to a similar extent, demonstrating FMNL1 as the dominant formin driving podosome-based macrophage migration.\",\n      \"method\": \"siRNA knockdown, pharmacological formin inhibition (SMIFH2), migration assays, podosome quantification in primary human macrophages\",\n      \"journal\": \"CellBio\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — KD and pharmacological inhibition with defined migratory phenotype in primary human cells; single lab\",\n      \"pmids\": [\"26942206\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"FMNL1 promotes NPC cell aggressiveness by increasing MTA1 transcription through an epigenetic mechanism: FMNL1 overexpression enhances binding of HDAC1 with Profilin2 in the cytoplasm, sequestering HDAC1 away from the MTA1 promoter, thereby de-repressing MTA1 expression.\",\n      \"method\": \"Co-immunoprecipitation (HDAC1–Profilin2 interaction), chromatin immunoprecipitation (ChIP) at MTA1 promoter, ectopic overexpression and siRNA knockdown, in vitro/in vivo invasion assays\",\n      \"journal\": \"Oncogene\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — ChIP and Co-IP with functional rescue; single lab with two orthogonal mechanistic methods\",\n      \"pmids\": [\"30013189\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"FMNL1γ isoform, but not FMNL1α or FMNL1β, bundles filamentous actin independently of the FH2 domain in vitro; while FMNL1γ inhibits actin assembly in vitro, it enhances cell adhesion and rescues migration in FMNL1-depleted breast adenocarcinoma cells. The three isoforms exhibit distinct subcellular localizations.\",\n      \"method\": \"In vitro actin assembly and bundling assay, isoform overexpression and siRNA rescue, cell adhesion and migration assays, fluorescence microscopy for localization\",\n      \"journal\": \"Journal of cellular biochemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1–2 / Moderate — in vitro actin bundling assay with domain mutant plus cellular rescue experiments; single lab\",\n      \"pmids\": [\"30977161\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"FMNL1 promotes ccRCC cell migration in vitro and tumor metastasis in vivo via transcriptional induction of CXCR2; FMNL1 increases CXCR2 expression through HDAC1, and knockdown of CXCR2 markedly attenuates FMNL1-enhanced cell motility. FMNL1 upregulation in ccRCC is mediated by loss of the transcription factor GATA3.\",\n      \"method\": \"ChIP, luciferase reporter assay, siRNA knockdown, ectopic overexpression, in vivo xenograft metastasis model, rescue experiments with CXCR2 knockdown\",\n      \"journal\": \"Frontiers in oncology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — ChIP and luciferase reporter confirm HDAC1/CXCR2 regulation; in vivo rescue data; single lab\",\n      \"pmids\": [\"33324547\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"In Drosophila epithelial cells, the FMNL1 ortholog Frl/Fmnl nucleates a persistent, homogeneous F-actin subpopulation at the medioapical cortex independently of Rho1; loss of Frl reduces network density and impairs homogeneous force transmission, causing tissue-scale morphogenetic defects, while overexpression increases network density.\",\n      \"method\": \"Drosophila genetic mutants, live-cell imaging, quantitative image analysis, F-actin network characterization\",\n      \"journal\": \"Nature cell biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — rigorous genetic loss- and gain-of-function in an in vivo model (Drosophila ortholog), replicated across multiple conditions with quantitative mechanistic readouts published in high-impact journal\",\n      \"pmids\": [\"32483386\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"In T cells, FMNL1 localizes predominantly to the rear of migrating cells and a portion physically associates with the nucleus; FMNL1 promotes efficient migration specifically in confined 3D environments by facilitating deformation of the rigid T cell nucleus, a mechanism distinct from mDia1 which promotes general motility in 3D via Myosin-II activity.\",\n      \"method\": \"In vivo T cell migration analysis, in vitro 2D and 3D migration assays, subcellular fractionation and nuclear association, FMNL1/mDia1 knockout comparison, Myosin-II inhibition\",\n      \"journal\": \"Frontiers in immunology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — in vivo plus in vitro 3D assays with nuclear localization and functional epistasis; single lab with multiple orthogonal approaches\",\n      \"pmids\": [\"39430739\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"Rab25-positive recycling endosomes coordinate positioning of FMNL1 and integrin β1 to the cell periphery together with Rho GTPase activation at the plasma membrane to generate and maintain F-actin-rich filopodial protrusions and promote cancer cell invasive migration in 3D matrix; direct magnetic manipulation of Rab25 vesicles to the cell periphery drives F-actin protrusion formation.\",\n      \"method\": \"Magnetogenetic manipulation of Rab25 vesicle positioning, live-cell imaging, Rho GTPase activation readout, F-actin protrusion quantification in 3D matrix\",\n      \"journal\": \"bioRxiv (preprint)\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — novel magnetogenetic approach but preprint, single lab, and FMNL1 is one of several cargoes with no direct functional dissection of FMNL1 specifically\",\n      \"pmids\": [],\n      \"is_preprint\": true\n    }\n  ],\n  \"current_model\": \"FMNL1 is an N-myristoylated formin-family actin nucleator/bundler predominantly expressed in hematopoietic cells that localizes to the cell membrane/cortex (regulated by autoinhibition via its DAD domain), podosomes, and the rear of migrating T cells, where it drives actin assembly for podosome dynamics, phagocytosis, lamellipodial protrusion, and nuclear deformation in confined environments; it acts downstream of RhoA, associates with β3 integrin and AHNAK1, negatively regulates Rac1 activity, epigenetically upregulates MTA1 and CXCR2 via cytoplasmic sequestration of HDAC1, and in oocyte meiosis operates in a RhoA–FMNL1–mDia1–Profilin1 pathway to coordinate actin cortex polarity and spindle organization.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"FMNL1 is a formin-family actin nucleator and bundler that drives cortical and protrusive actin assembly across hematopoietic, epithelial, and tumor cells [#1, #9, #11]. Its activity is gated by autoinhibition through the diaphanous autoinhibitory domain (DAD): a C-terminally truncated splice variant (FMNL1\\u03b3) or DAD deletion relieves this control and constitutively targets the protein to the membrane and cortex in an N-myristoylation\\u2013dependent manner, where it induces polarized membrane blebbing [#0]. The three isoforms localize distinctly, and FMNL1\\u03b3 bundles F-actin independently of its FH2 domain while supporting cell adhesion and migration [#9]. At the cell cortex FMNL1 localizes to macrophage podosome cores, co-precipitates with \\u03b23 integrin, and is the dominant formin sustaining podosome dynamics, adhesion, and macrophage migration [#1, #7]; it also drives pseudopod-based coiling phagocytosis of Borrelia together with mDia1 [#4]. FMNL1 operates within Rho GTPase circuitry: it acts downstream of RhoA in a RhoA\\u2013FMNL1\\u2013mDia1\\u2013Profilin1 pathway organizing the actin cortex and meiotic spindle in oocytes [#5, #6], and it negatively regulates Rac1 activity to control leukemia cell migration [#3]. In migrating T cells FMNL1 concentrates at the cell rear and physically associates with the nucleus, enabling deformation of the rigid nucleus for migration through confined 3D environments [#12]. Beyond its cytoskeletal roles, FMNL1 promotes tumor aggressiveness through an indirect epigenetic mechanism, sequestering HDAC1 in the cytoplasm to de-repress transcription of MTA1 and CXCR2 [#8, #10]. It additionally binds the scaffold AHNAK1 and modulates capacitative calcium influx [#2].\",\n  \"teleology\": [\n    {\n      \"year\": 2009,\n      \"claim\": \"Established how FMNL1 is targeted to the membrane and de-repressed, defining N-myristoylation and DAD-mediated autoinhibition as the switches controlling its cortical activity.\",\n      \"evidence\": \"Site-directed mutagenesis, splice-variant characterization, pharmacological inhibition, and live-cell imaging\",\n      \"pmids\": [\"19815554\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Did not identify the physiological signal that relieves DAD autoinhibition in vivo\", \"Functional consequence of blebbing for cell behavior unresolved\"]\n    },\n    {\n      \"year\": 2010,\n      \"claim\": \"Placed FMNL1 at adhesive actin structures by showing it occupies podosome cores, binds \\u03b23 integrin, and is required for podosome integrity and adhesion.\",\n      \"evidence\": \"siRNA knockdown, Co-IP with \\u03b23 integrin, and live/fixed imaging in primary macrophages\",\n      \"pmids\": [\"20617518\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Whether \\u03b23 integrin association is direct not established\", \"Did not test actin nucleation activity at podosomes directly\"]\n    },\n    {\n      \"year\": 2012,\n      \"claim\": \"Identified AHNAK1 as a direct FMNL1 partner and linked FMNL1 to calcium influx, extending its role beyond cytoskeletal scaffolding.\",\n      \"evidence\": \"MS interactome, Co-IP, domain-mapping pulldown, and calcium influx assays\",\n      \"pmids\": [\"23182705\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Mechanism connecting FMNL1/AHNAK1 to calcium entry unresolved\", \"Physiological context of the interaction unclear\"]\n    },\n    {\n      \"year\": 2013,\n      \"claim\": \"Defined FMNL1 as a negative regulator of Rac1, an unexpected role for a formin, with consequences for leukemia cell migration.\",\n      \"evidence\": \"Co-IP, Rac1 activity pull-down, and pharmacological Rac1-inhibition rescue of migration\",\n      \"pmids\": [\"23801653\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Molecular basis for suppression of Rac1 activity not established\", \"Generality beyond leukemia cells untested\"]\n    },\n    {\n      \"year\": 2013,\n      \"claim\": \"Showed FMNL1 is a required actin factor for coiling phagocytosis, acting alongside mDia1 at pathogen-contacting pseudopods.\",\n      \"evidence\": \"Immunofluorescence, ratiometric enrichment analysis, siRNA knockdown, and Borrelia internalization quantification\",\n      \"pmids\": [\"23460512\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Division of labor between FMNL1 and mDia1 not dissected\", \"Upstream receptor signaling not identified\"]\n    },\n    {\n      \"year\": 2015,\n      \"claim\": \"Positioned FMNL1 within a RhoA\\u2013FMNL1\\u2013mDia1\\u2013Profilin1 pathway and at spindle poles, linking it to actin cortex polarity and meiotic spindle organization.\",\n      \"evidence\": \"Morpholino knockdown, immunofluorescence, Western blotting, and RhoA-inhibitor epistasis in mouse oocytes\",\n      \"pmids\": [\"25447542\", \"26083584\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Mechanism by which FMNL1 controls mDia1 protein levels unknown\", \"How spindle-pole localization is established not resolved\"]\n    },\n    {\n      \"year\": 2015,\n      \"claim\": \"Demonstrated FMNL1 is the dominant formin driving podosome-based macrophage migration, distinguishing its contribution from other formins.\",\n      \"evidence\": \"siRNA knockdown, SMIFH2 pan-formin inhibition, and migration/podosome quantification in primary human macrophages\",\n      \"pmids\": [\"26942206\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Did not resolve which actin assembly step FMNL1 catalyzes at podosomes\", \"Upstream activation in macrophages untested\"]\n    },\n    {\n      \"year\": 2018,\n      \"claim\": \"Revealed a non-cytoskeletal, epigenetic mechanism whereby FMNL1 sequesters HDAC1 in the cytoplasm via Profilin2 to de-repress MTA1 and promote tumor aggressiveness.\",\n      \"evidence\": \"Co-IP, ChIP at the MTA1 promoter, overexpression/knockdown, and invasion assays in NPC cells\",\n      \"pmids\": [\"30013189\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Whether cytoplasmic HDAC1 sequestration depends on actin activity not addressed\", \"Direct FMNL1\\u2013HDAC1 versus indirect interaction unresolved\"]\n    },\n    {\n      \"year\": 2019,\n      \"claim\": \"Distinguished isoform-specific biochemistry, showing FMNL1\\u03b3 bundles actin independently of its FH2 domain while inhibiting assembly yet enhancing adhesion and migration.\",\n      \"evidence\": \"In vitro actin assembly/bundling assays with domain mutants plus isoform rescue in breast adenocarcinoma cells\",\n      \"pmids\": [\"30977161\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Structural basis of FH2-independent bundling not defined\", \"How opposing in vitro and cellular effects reconcile unclear\"]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"Extended the HDAC1-based epigenetic axis to CXCR2 and identified GATA3 loss as the driver of FMNL1 upregulation in ccRCC metastasis.\",\n      \"evidence\": \"ChIP, luciferase reporter, knockdown/overexpression, and in vivo xenograft metastasis with CXCR2-knockdown rescue\",\n      \"pmids\": [\"33324547\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Mechanism of GATA3 repression of FMNL1 not detailed\", \"Generality of the HDAC1 sequestration model across tumor types untested\"]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"Provided rigorous in vivo evidence that the FMNL1 ortholog nucleates a homogeneous medioapical F-actin network independent of Rho1, required for tissue-scale force transmission.\",\n      \"evidence\": \"Drosophila loss- and gain-of-function genetics with quantitative F-actin network imaging\",\n      \"pmids\": [\"32483386\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Direct extrapolation to mammalian FMNL1 regulation not shown\", \"Activating input for Rho1-independent nucleation unknown\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Identified a confinement-specific function: rear-localized, nucleus-associated FMNL1 deforms the rigid T cell nucleus to enable migration through tight 3D spaces, mechanistically distinct from mDia1.\",\n      \"evidence\": \"In vivo and in vitro 2D/3D migration assays, subcellular fractionation, FMNL1/mDia1 knockout comparison, and Myosin-II inhibition\",\n      \"pmids\": [\"39430739\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"How FMNL1 physically engages the nuclear envelope not defined\", \"Whether nuclear association is direct unresolved\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Proposed that Rab25 recycling endosomes co-deliver FMNL1 and integrin \\u03b21 to the periphery to generate filopodial protrusions during invasive migration.\",\n      \"evidence\": \"Magnetogenetic manipulation of Rab25 vesicles with F-actin protrusion quantification in 3D matrix (preprint)\",\n      \"pmids\": [],\n      \"confidence\": \"Low\",\n      \"gaps\": [\"Preprint not peer-reviewed; FMNL1 is one of several cargoes with no FMNL1-specific functional dissection\", \"Whether FMNL1 is required for the protrusions unaddressed\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"The signals that relieve FMNL1 autoinhibition in physiological contexts and how a single nucleator switches between cortical, podosomal, nuclear-deforming, and transcription-modulating roles remain unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No structural model of activation in mammalian cells\", \"Context-specific partner requirements not mapped\", \"Relationship between actin activity and the HDAC1 epigenetic role unknown\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0008092\", \"supporting_discovery_ids\": [9, 1, 11]},\n      {\"term_id\": \"GO:0098772\", \"supporting_discovery_ids\": [3, 5]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005886\", \"supporting_discovery_ids\": [0, 1]},\n      {\"term_id\": \"GO:0005856\", \"supporting_discovery_ids\": [1, 11]},\n      {\"term_id\": \"GO:0005829\", \"supporting_discovery_ids\": [8]},\n      {\"term_id\": \"GO:0005815\", \"supporting_discovery_ids\": [6]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-168256\", \"supporting_discovery_ids\": [1, 4, 12]},\n      {\"term_id\": \"R-HSA-1643685\", \"supporting_discovery_ids\": [8, 10]}\n    ],\n    \"complexes\": [],\n    \"partners\": [\"ITGB3\", \"AHNAK1\", \"RAC1\", \"DIAPH1\", \"HDAC1\", \"PFN2\"],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":6,"faith_total":8,"faith_pct":75.0}}