{"gene":"MICAL2","run_date":"2026-04-28T18:30:28","timeline":{"discoveries":[{"year":2014,"finding":"MICAL-2 mediates redox-dependent depolymerization of nuclear actin by oxidizing actin subunits, which decreases nuclear G-actin levels, prevents MRTF-A nuclear export, and thereby activates SRF/MRTF-A-dependent gene transcription in response to NGF and serum. MICAL-2 was also identified as a target of the SRF/MRTF-A inhibitor CCG-1423.","method":"Knockdown/overexpression in cells, nuclear fractionation, live-cell imaging of nuclear actin dynamics, small-molecule inhibition (CCG-1423)","journal":"Cell","confidence":"High","confidence_rationale":"Tier 2 — multiple orthogonal methods, highly cited foundational study replicated by subsequent labs","pmids":["24440334"],"is_preprint":false},{"year":2013,"finding":"The MICAL-2 monooxygenase domain is a flavin-dependent enzyme that uses NADPH (preferentially, via the proR hydride) to reduce its flavin; this reductive half-reaction is strongly stimulated by F-actin, consistent with the Class A aromatic hydroxylase regulatory mechanism where substrate binding promotes flavin reduction and prevents wasteful H2O2 production.","method":"In vitro enzymatic assay with purified monooxygenase domain, kinetic isotope effect measurement with deuterium-labeled NADPH, stopped-flow kinetics with and without F-actin","journal":"Biochemistry","confidence":"High","confidence_rationale":"Tier 1 — rigorous in vitro enzymology with purified protein, isotope labeling, and kinetic analysis","pmids":["23927065"],"is_preprint":false},{"year":2021,"finding":"MICAL2 mediates methionine oxidation of ARP3B, a specific subunit of the ARP2/3 complex, thereby destabilizing ARP2/3 complexes and leading to disassembly of branched actin filaments.","method":"Biochemical reconstitution and functional analysis of ARP2/3 isoform-specific regulation (reported as a commentary on primary data from Galloni et al.)","journal":"The Journal of cell biology","confidence":"Medium","confidence_rationale":"Tier 1 method (methionine oxidation assay) described in referenced primary paper; citation is a commentary summarizing that work","pmids":["34264264"],"is_preprint":false},{"year":2018,"finding":"MICAL2 physically interacts with p53, retains it in the cytoplasm, and oxidizes p53 at methionine 40 and methionine 160, which promotes p53 ubiquitin-mediated degradation and reduces p53 tumor-suppressive function in colorectal cancer cells.","method":"Co-immunoprecipitation, reverse-phase nano ESI-LCMS mass spectrometry to detect methionine oxidation, immunofluorescence of p53 localization, ubiquitination assay, p53+/+ vs p53-/- cell comparison, in vivo xenograft","journal":"Theranostics","confidence":"High","confidence_rationale":"Tier 1–2 — mass spectrometry identification of specific oxidized residues plus functional epistasis in p53-null cells and in vivo confirmation","pmids":["30555547"],"is_preprint":false},{"year":2021,"finding":"ARG (Abelson-related gene) kinase interacts with MICAL2 and phosphorylates it at Tyr445, Tyr463, and Tyr488; phosphorylation at Tyr445 and Tyr463 (but not Tyr488) enhances MICAL2-mediated F-actin disassembly, which directly oxidizes methionine 44 and 47 of F-actin.","method":"Direct phosphorylation assay, mass spectrometry confirmation of phosphorylation sites, non-phosphorylatable phenylalanine substitution mutants tested in F-actin disassembly assays and cell proliferation rescue experiments","journal":"Oncogene","confidence":"High","confidence_rationale":"Tier 1 — in vitro phosphorylation assay with MS validation, site-specific mutagenesis with functional readout","pmids":["34750518"],"is_preprint":false},{"year":2016,"finding":"MICAL2 knockdown in human cancer cells causes mesenchymal-to-epithelial transition and loss of motility/invasion, while re-expression of MICAL2 cDNA in depleted cells induces epithelial-to-mesenchymal transition, demonstrating MICAL2 is a direct regulator of EMT.","method":"siRNA/shRNA knockdown, cDNA rescue, cell morphology, migration and invasion assays","journal":"Oncotarget","confidence":"Medium","confidence_rationale":"Tier 2 — clean KO/rescue with defined phenotype, but single lab without structural validation","pmids":["26689989"],"is_preprint":false},{"year":2017,"finding":"MICAL2 maintains EGFR protein stability by delaying EGFR degradation in a Rac1-dependent manner, leading to sustained EGFR/P38/HSP27 and P38/MMP9 signaling and promotion of breast cancer cell migration.","method":"Gene overexpression and knockdown, Western blotting for EGFR degradation kinetics, Rac1 pull-down activity assay, wound-healing migration assay","journal":"Acta physiologica","confidence":"Medium","confidence_rationale":"Tier 2–3 — multiple methods in one lab demonstrating Rac1-dependent mechanism, but no reconstitution","pmids":["28719045"],"is_preprint":false},{"year":2020,"finding":"MICAL2 is a nucleocytoplasmic shuttling protein; its nuclear export depends on myosin-9 interaction and its C-terminal fragment. Cytoplasmic (but not nuclear-restricted) MICAL2 promotes tumor malignancy through AKT and myosin-9 pathways, and nuclear export inhibitors or myosin-9 inhibitors reduce MICAL2-driven tumor promotion.","method":"Subcellular fractionation, nuclear export inhibitor treatment, myosin-9 siRNA knockdown, domain-deletion constructs (MICAL2-ΔC), in vitro and in vivo tumor assays","journal":"Cancer letters","confidence":"Medium","confidence_rationale":"Tier 2 — localization tied to functional consequence with domain mapping, single lab","pmids":["32360180"],"is_preprint":false},{"year":2021,"finding":"MICAL2 promotes gastric cancer cell migration by inducing MRTF-A nuclear translocation in response to EGF/serum (via ROS generation), which subsequently activates CDC42 and increases MMP9 expression; silencing MICAL2 blocks CDC42 activation and MRTF-A nuclear retention.","method":"siRNA knockdown, overexpression, DCFH-DA ROS staining, nuclear/cytoplasmic fractionation, CDC42 pull-down activity assay, qPCR/Western blot for MMP9","journal":"Frontiers in molecular biosciences","confidence":"Medium","confidence_rationale":"Tier 2 — multiple orthogonal assays in single lab placing MICAL2 upstream of MRTF-A and CDC42","pmids":["33842533"],"is_preprint":false},{"year":2021,"finding":"MICAL2 promotes gastric cancer cell proliferation through two parallel mechanisms: ROS generation and Cdc42 activation, both of which independently drive YAP dephosphorylation and YAP nuclear translocation; ROS scavenging (NAC/tempol) reverses MICAL2-mediated YAP activation.","method":"Overexpression/knockdown, ROS measurement, p-YAP/YAP ratio by Western blot, Cdc42 pull-down, nuclear/cytoplasmic YAP fractionation, ROS scavenger rescue experiments","journal":"Oxidative medicine and cellular longevity","confidence":"Medium","confidence_rationale":"Tier 2 — pharmacological rescue orthogonally validates ROS mechanism; single lab","pmids":["34650666"],"is_preprint":false},{"year":2022,"finding":"MICAL2 promotes E-cadherin ubiquitination and degradation in a Cdc42-dependent manner, disrupting the E-cadherin/β-catenin complex and releasing β-catenin for nuclear translocation to drive gastric cancer cell migration; GSK3β inhibition rescues the MICAL2 knockdown migratory phenotype.","method":"Knockdown, co-immunoprecipitation of E-cadherin/β-catenin complex, nuclear/cytoplasmic fractionation, ubiquitination assay, Cdc42 pull-down, GSK3β inhibitor (LiCl) rescue","journal":"Cell communication and signaling","confidence":"Medium","confidence_rationale":"Tier 2 — reciprocal Co-IP plus epistasis with LiCl rescue; single lab","pmids":["36064550"],"is_preprint":false},{"year":2021,"finding":"MICAL2 mediates myofibroblast differentiation in a SRF/MRTF-A-dependent manner: MICAL2 knockdown inhibits MRTF-A nuclear translocation in TGF-β1-stimulated fibroblasts and attenuates α-SMA, collagen-1, and fibronectin expression as well as epidural fibrosis in vivo.","method":"shRNA lentiviral knockdown, immunofluorescence of MRTF-A localization, Western blot for fibrosis markers, in vivo rat laminectomy model","journal":"Life sciences","confidence":"Medium","confidence_rationale":"Tier 2 — in vivo and in vitro epistasis placing MICAL2 upstream of MRTF-A nuclear translocation; single lab","pmids":["33453238"],"is_preprint":false},{"year":2020,"finding":"MICAL2 is essential for myogenic lineage commitment: MICAL2 expression increases during skeletal, smooth, and cardiac muscle differentiation, it localizes to the nucleus of regenerating muscle fibers, and in vivo CRISPR-Cas9 deletion of Mical2 causes actin defects and loss of skeletal muscle homeostasis/functionality.","method":"In vivo Cas9/gRNA delivery, immunofluorescence localization, differentiation assays of adult stem cells and PSCs, muscle functional assessment","journal":"Cell death & disease","confidence":"Medium","confidence_rationale":"Tier 2 — in vivo CRISPR loss-of-function with defined structural phenotype; single lab","pmids":["32811811"],"is_preprint":false},{"year":2019,"finding":"MICAL2 is required for endothelial cell response to VEGF: MICAL2 enters the p130Cas interactome in response to VEGF in HUVECs, and MICAL2 KD disables EC VEGF response, viability, and motility; MICAL2 is selectively expressed in neo-angiogenic (but not normal) capillary endothelia in human tumors.","method":"siRNA knockdown, CCG-1423 pharmacological inhibition, whole-genome gene expression profiling, immunohistochemistry of human tumor sections, proteomic interactome (p130Cas)","journal":"Biochimica et biophysica acta. Molecular basis of disease","confidence":"Medium","confidence_rationale":"Tier 2–3 — interactome and KD with functional readout; single lab, no reconstitution","pmids":["31004710"],"is_preprint":false},{"year":2023,"finding":"Gas6/Axl receptor tyrosine kinase signaling activates SRF/MRTF-A-dependent transcription through MICAL2: Axl inhibition blocks serum-induced SRF/MRTF-A gene expression, Gas6/Axl-induced transcription requires MICAL2, and Gas6/Axl signaling promotes nuclear localization of MICAL2.","method":"Axl inhibitor treatment, MICAL2 siRNA knockdown, nuclear MICAL2 localization imaging, gene expression analysis of SRF/MRTF-A target genes, cell invasion assay","journal":"Genes","confidence":"Medium","confidence_rationale":"Tier 2 — epistasis placing MICAL2 downstream of Gas6/Axl with functional rescue; single lab","pmids":["38137053"],"is_preprint":false},{"year":2021,"finding":"MICAL2 interacts with TGF receptor type I (TGFRI) and activates TGF-β/p-Smad2/EMT-like signaling to promote glioblastoma cell proliferation and migration.","method":"Co-immunoprecipitation of MICAL2-TGFRI interaction, knockdown of MICAL2, Western blot for p-Smad2, in vitro and in vivo (nude mouse) proliferation/invasion assays","journal":"Frontiers in oncology","confidence":"Low","confidence_rationale":"Tier 3 — single Co-IP with partial mechanistic follow-up; single lab","pmids":["34868922"],"is_preprint":false},{"year":2026,"finding":"MICAL2 acts as a constitutively active actin-regulatory monooxygenase at endosomes: MICAL2 depletion or inhibition of its monooxygenase activity causes a substantial increase in Arp2/3-mediated branched actin at endosomes, impairing endosome fission and clathrin-dependent cargo recycling to the plasma membrane.","method":"siRNA knockdown, monooxygenase inhibitor treatment, fluorescence imaging of branched actin at endosomes, endosome fission and cargo recycling functional assays","journal":"Journal of cell science","confidence":"Medium","confidence_rationale":"Tier 2 — genetic and pharmacological loss-of-function with defined organelle-level phenotype, monooxygenase-specific inhibitor controls","pmids":["41797580"],"is_preprint":false},{"year":2025,"finding":"MICAL2 facilitates p53 ubiquitination and degradation in NPC cells by recruiting the E3 ubiquitin ligase MDM2 to p53, in addition to influencing nuclear translocation of p53, thereby inhibiting ferroptosis and promoting tumor progression.","method":"Co-immunoprecipitation of MICAL2-MDM2-p53 complex, ubiquitination assay, nuclear translocation imaging, transcriptome sequencing, RACE experiments","journal":"Oncogene","confidence":"Medium","confidence_rationale":"Tier 2 — Co-IP demonstrating MDM2 recruitment plus ubiquitination assay; single lab","pmids":["41832266"],"is_preprint":false},{"year":2019,"finding":"MICAL2 activates ERK1/2 signaling in pulmonary arterial smooth muscle cells to promote proliferation; miR-205-5p suppresses this by targeting the MICAL2 3'UTR, and ERK1/2 inhibition blocks MICAL2-mediated proliferation.","method":"Luciferase reporter assay for miR-205-5p targeting of MICAL2 3'UTR, MICAL2 overexpression, ERK1/2 inhibitor rescue, cell proliferation assay","journal":"Microvascular research","confidence":"Low","confidence_rationale":"Tier 3 — single lab, pathway placement via inhibitor only, no direct mechanistic link between MICAL2 catalytic activity and ERK activation","pmids":["30853343"],"is_preprint":false},{"year":2024,"finding":"MICAL2 promotes ERK1/2 and AKT activation and macropinocytosis in pancreatic ductal adenocarcinoma cells, and upregulates KRAS and EMT signaling pathways; MRTF-B (but not MRTF-A) phenocopies MICAL2-driven in vivo tumor growth and metastasis.","method":"Loss- and gain-of-function experiments, Western blot for ERK1/2/AKT phosphorylation, macropinocytosis assay, in vivo xenograft/metastasis models, transcriptional analysis","journal":"Cancer research","confidence":"Medium","confidence_rationale":"Tier 2 — multiple orthogonal assays in vitro and in vivo; single lab with peer-reviewed publication","pmids":["39745352"],"is_preprint":false}],"current_model":"MICAL2 is a nuclear and cytoplasmic flavin-dependent monooxygenase that uses NADPH (stimulated by F-actin binding) to oxidize specific methionine residues on F-actin (Met44/47) and ARP3B, thereby driving actin depolymerization and branched-actin disassembly; in the nucleus this reduces G-actin levels to retain MRTF-A and activate SRF/MRTF-A transcription (downstream of NGF, serum, and Gas6/Axl signaling), while in the cytoplasm it stabilizes EGFR, activates Rac1/Cdc42/RhoA, promotes YAP nuclear translocation via ROS, oxidizes and destabilizes p53 (recruiting MDM2 for ubiquitination), facilitates endosome fission by attenuating branched actin, and is itself regulated by ARG kinase phosphorylation at Tyr445/463 and myosin-9-dependent nuclear export."},"narrative":{"teleology":[{"year":2013,"claim":"Establishing MICAL2 as a bona fide flavin-dependent monooxygenase with an F-actin-gated catalytic cycle resolved how MICAL2 avoids futile ROS production and couples NADPH consumption to its substrate.","evidence":"Purified monooxygenase domain kinetics with stopped-flow, deuterium-labeled NADPH isotope effects, and F-actin stimulation in vitro","pmids":["23927065"],"confidence":"High","gaps":["No structural basis for F-actin-induced allosteric activation","Product (oxygenated actin) characterization incomplete at this stage","Regulation of the monooxygenase domain by other MICAL2 domains not addressed"]},{"year":2014,"claim":"Demonstrating that MICAL2 oxidizes nuclear actin to deplete G-actin and retain MRTF-A in the nucleus established a direct redox-to-transcription axis, answering how SRF/MRTF-A programs are activated without classical Rho-driven actin dynamics.","evidence":"Knockdown/overexpression in cells, nuclear fractionation, live-cell imaging, CCG-1423 inhibition","pmids":["24440334"],"confidence":"High","gaps":["Identity of nuclear actin methionine residues oxidized by MICAL2 not shown","How MICAL2 itself enters the nucleus was unknown","Relative contribution vs. MICAL1/MICAL3 in nuclear actin remodeling not resolved"]},{"year":2016,"claim":"Showing that MICAL2 depletion reverses EMT and re-expression restores it placed the enzyme as a functional driver of epithelial–mesenchymal plasticity, not merely a bystander.","evidence":"siRNA/shRNA knockdown and cDNA rescue with morphology, migration, and invasion assays in cancer cells","pmids":["26689989"],"confidence":"Medium","gaps":["Whether EMT regulation requires monooxygenase activity or scaffolding was not separated","No direct actin oxidation measurement in this context","Single-lab finding"]},{"year":2017,"claim":"Identifying MICAL2 as a stabilizer of EGFR through Rac1-dependent delay of receptor degradation extended its role beyond actin oxidation to receptor tyrosine kinase signaling.","evidence":"Overexpression/knockdown with EGFR degradation kinetics and Rac1 pull-down in breast cancer cells","pmids":["28719045"],"confidence":"Medium","gaps":["Whether MICAL2 monooxygenase activity is required for EGFR stabilization was not tested","No reconstitution of MICAL2–EGFR–Rac1 axis","Single lab"]},{"year":2018,"claim":"Identifying p53 Met40/Met160 as direct MICAL2 oxidation targets that promote ubiquitin-mediated p53 degradation revealed a non-actin substrate and a tumor-suppressor-inactivation mechanism.","evidence":"Co-IP, nano ESI-LCMS for methionine oxidation sites, ubiquitination assay, p53-null epistasis, xenograft","pmids":["30555547"],"confidence":"High","gaps":["Whether oxidation alone suffices for degradation or requires additional cofactors was unclear","E3 ligase identity not identified in this study","Specificity among MICAL family members not tested"]},{"year":2019,"claim":"Placing MICAL2 in the VEGF-responsive p130Cas interactome in endothelial cells and showing selective expression in neo-angiogenic tumor capillaries defined a vascular-specific function.","evidence":"siRNA knockdown in HUVECs, proteomic interactome, immunohistochemistry of human tumor vasculature","pmids":["31004710"],"confidence":"Medium","gaps":["Direct enzymatic substrates in the endothelial VEGF response not identified","Interactome role of p130Cas–MICAL2 interaction not mechanistically resolved","Single lab"]},{"year":2020,"claim":"Defining MICAL2 as a nucleocytoplasmic shuttling protein whose export depends on myosin-9 and whose cytoplasmic (not nuclear) pool drives tumorigenesis resolved how its subcellular distribution gates distinct outputs.","evidence":"Subcellular fractionation, nuclear export inhibitors, myosin-9 siRNA, domain-deletion constructs, in vivo tumor assays","pmids":["32811811","32360180"],"confidence":"Medium","gaps":["Nuclear import signal/mechanism not characterized","Whether nuclear vs. cytoplasmic pools have distinct substrates beyond actin was unknown","Myosin-9 interaction mode (direct or bridged) not determined"]},{"year":2021,"claim":"Multiple converging studies established that MICAL2 oxidizes ARP3B to disassemble branched actin, is activated by ARG kinase phosphorylation at Tyr445/463, and signals through ROS/Cdc42 to activate YAP nuclear translocation and MRTF-A, integrating upstream kinase regulation with downstream transcriptional effectors.","evidence":"Biochemical ARP3B oxidation assay, ARG kinase phosphorylation with MS and mutagenesis, ROS scavenger rescue of YAP activation, Cdc42 pull-down, in vivo fibrosis model","pmids":["34264264","34750518","34650666","33842533","33453238"],"confidence":"High","gaps":["Whether ARG-mediated phosphorylation affects MICAL2 substrate selectivity (actin vs. non-actin) was not tested","Structural basis for Tyr445/463 activation of monooxygenase domain unknown","Relative contribution of direct actin oxidation vs. ROS generation to downstream signaling not quantified"]},{"year":2022,"claim":"Demonstrating that MICAL2 promotes E-cadherin ubiquitination and β-catenin nuclear translocation via Cdc42 connected its actin-regulatory activity to adherens junction disassembly and Wnt-like signaling.","evidence":"Reciprocal Co-IP of E-cadherin/β-catenin, ubiquitination assay, Cdc42 pull-down, GSK3β inhibitor rescue","pmids":["36064550"],"confidence":"Medium","gaps":["E3 ligase mediating E-cadherin ubiquitination downstream of MICAL2 not identified","Whether MICAL2 directly oxidizes E-cadherin or acts indirectly through actin not resolved","Single lab"]},{"year":2023,"claim":"Placing Gas6/Axl upstream of MICAL2 nuclear localization and SRF/MRTF-A transcription identified a new receptor pathway that converges on MICAL2's nuclear actin-remodeling function.","evidence":"Axl inhibitor treatment, MICAL2 siRNA epistasis, nuclear MICAL2 imaging, SRF/MRTF-A target gene expression","pmids":["38137053"],"confidence":"Medium","gaps":["Phosphorylation or other post-translational modification linking Axl to MICAL2 nuclear import not identified","Whether Axl acts through ARG kinase to phosphorylate MICAL2 not tested","Single lab"]},{"year":2025,"claim":"Identifying MDM2 as the E3 ligase recruited by MICAL2 to ubiquitinate oxidized p53 completed the mechanistic pathway from MICAL2-mediated p53 oxidation to proteasomal degradation and ferroptosis inhibition.","evidence":"Co-IP of MICAL2–MDM2–p53 ternary complex, ubiquitination assay, transcriptome sequencing in NPC cells","pmids":["41832266"],"confidence":"Medium","gaps":["Whether MICAL2 oxidation of p53 is prerequisite for MDM2 binding or operates in parallel not dissected","Structural basis of MICAL2–MDM2 interaction unknown","Single lab, single cancer type"]},{"year":2026,"claim":"Demonstrating that MICAL2 constitutively removes branched actin from endosomes to enable fission and cargo recycling established its first non-nuclear, non-migratory housekeeping function in membrane trafficking.","evidence":"siRNA and monooxygenase inhibitor treatment, fluorescence imaging of endosomal branched actin, fission and recycling assays","pmids":["41797580"],"confidence":"Medium","gaps":["Whether MICAL2 is recruited to endosomes via specific adaptors or acts diffusely not known","Redundancy with MICAL1 or MICAL3 at endosomes not tested","Impact on non-clathrin cargo recycling pathways not assessed"]},{"year":null,"claim":"A comprehensive structural model of full-length MICAL2 explaining how domain architecture, post-translational modifications, and subcellular targeting coordinately regulate substrate selectivity (actin vs. ARP3B vs. p53) is lacking.","evidence":"","pmids":[],"confidence":"Low","gaps":["No full-length MICAL2 structure available","Quantitative partitioning of ROS-mediated vs. direct methionine-oxidation signaling not determined","In vivo genetic models of catalytic-dead vs. null alleles needed to separate enzymatic from scaffolding functions"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0016491","term_label":"oxidoreductase activity","supporting_discovery_ids":[0,1,2,3,4,16]},{"term_id":"GO:0140096","term_label":"catalytic activity, acting on a protein","supporting_discovery_ids":[3,4,17]},{"term_id":"GO:0008092","term_label":"cytoskeletal protein binding","supporting_discovery_ids":[0,1,4,16]}],"localization":[{"term_id":"GO:0005634","term_label":"nucleus","supporting_discovery_ids":[0,7,12,14]},{"term_id":"GO:0005829","term_label":"cytosol","supporting_discovery_ids":[3,7]},{"term_id":"GO:0005768","term_label":"endosome","supporting_discovery_ids":[16]}],"pathway":[{"term_id":"R-HSA-74160","term_label":"Gene expression (Transcription)","supporting_discovery_ids":[0,8,11,14]},{"term_id":"R-HSA-162582","term_label":"Signal Transduction","supporting_discovery_ids":[6,9,10,19]},{"term_id":"R-HSA-5653656","term_label":"Vesicle-mediated transport","supporting_discovery_ids":[16]},{"term_id":"R-HSA-5357801","term_label":"Programmed Cell Death","supporting_discovery_ids":[3,17]}],"complexes":[],"partners":["ABL2","MYH9","TP53","MDM2","ACTR3B","MRTFA","AXL","BCAR1"],"other_free_text":[]},"mechanistic_narrative":"MICAL2 is a flavin-dependent monooxygenase that oxidizes specific methionine residues on actin and actin-regulatory proteins, linking redox-driven cytoskeletal remodeling to transcriptional control, endosomal trafficking, and signal transduction. Its NADPH-consuming reductive half-reaction is allosterically stimulated by F-actin binding, and it directly oxidizes Met44/Met47 on F-actin to drive depolymerization — an activity enhanced by ARG kinase phosphorylation at Tyr445/463 — and also oxidizes ARP3B to destabilize branched actin networks required for endosome fission and clathrin-dependent cargo recycling [PMID:23927065, PMID:34750518, PMID:34264264, PMID:41797580]. In the nucleus, MICAL2-mediated actin oxidation reduces G-actin levels, retaining MRTF-A to activate SRF/MRTF-A-dependent transcription downstream of NGF, serum, TGF-β1, and Gas6/Axl signaling, thereby regulating programs including EMT, myofibroblast differentiation, and myogenic commitment [PMID:24440334, PMID:33453238, PMID:38137053, PMID:32811811]. MICAL2 also oxidizes p53 at Met40/Met160, promoting MDM2-dependent ubiquitination and degradation of p53, and activates ROS/Cdc42 signaling to drive YAP nuclear translocation, E-cadherin degradation, and β-catenin release [PMID:30555547, PMID:41832266, PMID:34650666, PMID:36064550]."},"prefetch_data":{"uniprot":{"accession":"O94851","full_name":"[F-actin]-monooxygenase MICAL2","aliases":["MICAL C-terminal-like protein","Mical-cL","Molecule interacting with CasL protein 2","MICAL-2"],"length_aa":1957,"mass_kda":219.1,"function":"Methionine monooxygenase that promotes depolymerization of F-actin by mediating oxidation of residues 'Met-44' and 'Met-47' on actin to form methionine-sulfoxide, resulting in actin filament disassembly and preventing repolymerization (PubMed:24440334, PubMed:29343822). Regulates the disassembly of branched actin networks also by oxidizing ARP3B-containing ARP2/3 complexes leading to ARP3B dissociation from the network (PubMed:34106209). Acts as a key regulator of the SRF signaling pathway elicited by nerve growth factor and serum: mediates oxidation and subsequent depolymerization of nuclear actin, leading to increase MKL1/MRTF-A presence in the nucleus and promote SRF:MKL1/MRTF-A-dependent gene transcription. Does not activate SRF:MKL1/MRTF-A through RhoA (PubMed:24440334)","subcellular_location":"Nucleus; Cytoplasm","url":"https://www.uniprot.org/uniprotkb/O94851/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/MICAL2","classification":"Not Classified","n_dependent_lines":0,"n_total_lines":1208,"dependency_fraction":0.0},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[{"gene":"BCAP31","stoichiometry":0.2},{"gene":"COPA","stoichiometry":0.2},{"gene":"COPB2","stoichiometry":0.2},{"gene":"COPE","stoichiometry":0.2},{"gene":"PGRMC1","stoichiometry":0.2}],"url":"https://opencell.sf.czbiohub.org/search/MICAL2","total_profiled":1310},"omim":[{"mim_id":"608882","title":"MICROTUBULE-ASSOCIATED MONOOXYGENASE, CALPONIN AND LIM DOMAINS-CONTAINING, 3; MICAL3","url":"https://www.omim.org/entry/608882"},{"mim_id":"608881","title":"MICROTUBULE-ASSOCIATED MONOOXYGENASE, CALPONIN AND LIM DOMAINS-CONTAINING, 2; MICAL2","url":"https://www.omim.org/entry/608881"},{"mim_id":"607129","title":"MICROTUBULE-ASSOCIATED MONOOXYGENASE, CALPONIN AND LIM DOMAINS-CONTAINING, 1; MICAL1","url":"https://www.omim.org/entry/607129"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Uncertain","locations":[{"location":"Cytosol","reliability":"Uncertain"},{"location":"Nucleoplasm","reliability":"Additional"},{"location":"Plasma membrane","reliability":"Additional"}],"tissue_specificity":"Tissue enhanced","tissue_distribution":"Detected in many","driving_tissues":[{"tissue":"brain","ntpm":138.2}],"url":"https://www.proteinatlas.org/search/MICAL2"},"hgnc":{"alias_symbol":["KIAA0750","FLJ14966"],"prev_symbol":["MICALCL"]},"alphafold":{"accession":"O94851","domains":[{"cath_id":"-","chopping":"2-75","consensus_level":"medium","plddt":92.6636,"start":2,"end":75},{"cath_id":"3.50.50.60","chopping":"81-235_379-490","consensus_level":"high","plddt":94.3988,"start":81,"end":490},{"cath_id":"1.10.418.10","chopping":"520-622","consensus_level":"high","plddt":92.0395,"start":520,"end":622},{"cath_id":"2.10.110.10","chopping":"1002-1068","consensus_level":"medium","plddt":83.2458,"start":1002,"end":1068},{"cath_id":"3.30.70","chopping":"241-372","consensus_level":"high","plddt":92.5068,"start":241,"end":372}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/O94851","model_url":"https://alphafold.ebi.ac.uk/files/AF-O94851-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-O94851-F1-predicted_aligned_error_v6.png","plddt_mean":56.28},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=MICAL2","jax_strain_url":"https://www.jax.org/strain/search?query=MICAL2"},"sequence":{"accession":"O94851","fasta_url":"https://rest.uniprot.org/uniprotkb/O94851.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/O94851/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/O94851"}},"corpus_meta":[{"pmid":"24440334","id":"PMC_24440334","title":"Redox modification of nuclear actin by MICAL-2 regulates SRF signaling.","date":"2014","source":"Cell","url":"https://pubmed.ncbi.nlm.nih.gov/24440334","citation_count":139,"is_preprint":false},{"pmid":"36271377","id":"PMC_36271377","title":"Exosome-like nanovesicles derived from Phellinus linteus inhibit Mical2 expression through cross-kingdom regulation and inhibit ultraviolet-induced skin aging.","date":"2022","source":"Journal of nanobiotechnology","url":"https://pubmed.ncbi.nlm.nih.gov/36271377","citation_count":72,"is_preprint":false},{"pmid":"16675569","id":"PMC_16675569","title":"Expression of novel molecules, MICAL2-PV (MICAL2 prostate cancer variants), increases with high Gleason score and prostate cancer progression.","date":"2006","source":"Clinical cancer research : an official journal of the American Association for Cancer Research","url":"https://pubmed.ncbi.nlm.nih.gov/16675569","citation_count":59,"is_preprint":false},{"pmid":"26689989","id":"PMC_26689989","title":"MICAL2 is a novel human cancer gene controlling mesenchymal to epithelial transition involved in cancer growth and invasion.","date":"2016","source":"Oncotarget","url":"https://pubmed.ncbi.nlm.nih.gov/26689989","citation_count":55,"is_preprint":false},{"pmid":"28719045","id":"PMC_28719045","title":"MICAL2 promotes breast cancer cell migration by maintaining epidermal growth factor receptor (EGFR) stability and EGFR/P38 signalling activation.","date":"2017","source":"Acta physiologica (Oxford, England)","url":"https://pubmed.ncbi.nlm.nih.gov/28719045","citation_count":39,"is_preprint":false},{"pmid":"30853343","id":"PMC_30853343","title":"miR-205-5p suppresses pulmonary vascular smooth muscle cell proliferation by targeting MICAL2-mediated Erk1/2 signaling.","date":"2019","source":"Microvascular research","url":"https://pubmed.ncbi.nlm.nih.gov/30853343","citation_count":36,"is_preprint":false},{"pmid":"32360180","id":"PMC_32360180","title":"MICAL2 is a novel nucleocytoplasmic shuttling protein promoting cancer invasion and growth of lung adenocarcinoma.","date":"2020","source":"Cancer letters","url":"https://pubmed.ncbi.nlm.nih.gov/32360180","citation_count":35,"is_preprint":false},{"pmid":"29483957","id":"PMC_29483957","title":"Overexpression of MICAL2, a novel tumor-promoting factor, accelerates tumor progression through regulating cell proliferation and EMT.","date":"2018","source":"Journal of Cancer","url":"https://pubmed.ncbi.nlm.nih.gov/29483957","citation_count":29,"is_preprint":false},{"pmid":"34970696","id":"PMC_34970696","title":"lnc‑MICAL2‑1 sponges miR‑25 to regulate DKK3 expression and inhibits activation of the Wnt/β‑catenin signaling pathway in breast cancer.","date":"2021","source":"International journal of molecular medicine","url":"https://pubmed.ncbi.nlm.nih.gov/34970696","citation_count":29,"is_preprint":false},{"pmid":"23927065","id":"PMC_23927065","title":"Actin stimulates reduction of the MICAL-2 monooxygenase domain.","date":"2013","source":"Biochemistry","url":"https://pubmed.ncbi.nlm.nih.gov/23927065","citation_count":23,"is_preprint":false},{"pmid":"32811811","id":"PMC_32811811","title":"MICAL2 is essential for myogenic lineage commitment.","date":"2020","source":"Cell death & disease","url":"https://pubmed.ncbi.nlm.nih.gov/32811811","citation_count":21,"is_preprint":false},{"pmid":"31004710","id":"PMC_31004710","title":"MICAL2 is expressed in cancer associated neo-angiogenic capillary endothelia and it is required for endothelial cell viability, motility and VEGF response.","date":"2019","source":"Biochimica et biophysica acta. Molecular basis of disease","url":"https://pubmed.ncbi.nlm.nih.gov/31004710","citation_count":21,"is_preprint":false},{"pmid":"34650666","id":"PMC_34650666","title":"MICAL2 Contributes to Gastric Cancer Cell Proliferation by Promoting YAP Dephosphorylation and Nuclear Translocation.","date":"2021","source":"Oxidative medicine and cellular longevity","url":"https://pubmed.ncbi.nlm.nih.gov/34650666","citation_count":17,"is_preprint":false},{"pmid":"30555547","id":"PMC_30555547","title":"MICAL2 Mediates p53 Ubiquitin Degradation through Oxidating p53 Methionine 40 and 160 and Promotes Colorectal Cancer Malignance.","date":"2018","source":"Theranostics","url":"https://pubmed.ncbi.nlm.nih.gov/30555547","citation_count":16,"is_preprint":false},{"pmid":"34868922","id":"PMC_34868922","title":"MICAL2 Promotes Proliferation and Migration of Glioblastoma Cells Through TGF-β/p-Smad2/EMT-Like Signaling Pathway.","date":"2021","source":"Frontiers in oncology","url":"https://pubmed.ncbi.nlm.nih.gov/34868922","citation_count":15,"is_preprint":false},{"pmid":"33842533","id":"PMC_33842533","title":"MICAL2 Facilitates Gastric Cancer Cell Migration via MRTF-A-Mediated CDC42 Activation.","date":"2021","source":"Frontiers in molecular biosciences","url":"https://pubmed.ncbi.nlm.nih.gov/33842533","citation_count":15,"is_preprint":false},{"pmid":"36064550","id":"PMC_36064550","title":"MICAL2 contributes to gastric cancer cell migration via Cdc42-dependent activation of E-cadherin/β-catenin signaling pathway.","date":"2022","source":"Cell communication and signaling : CCS","url":"https://pubmed.ncbi.nlm.nih.gov/36064550","citation_count":14,"is_preprint":false},{"pmid":"32659284","id":"PMC_32659284","title":"LncRNA Mical2/miR-203a-3p sponge participates in epithelial-mesenchymal transition by targeting p66Shc in liver fibrosis.","date":"2020","source":"Toxicology and applied pharmacology","url":"https://pubmed.ncbi.nlm.nih.gov/32659284","citation_count":13,"is_preprint":false},{"pmid":"34750518","id":"PMC_34750518","title":"Phosphorylation of MICAL2 by ARG promotes head and neck cancer tumorigenesis by regulating skeletal rearrangement.","date":"2021","source":"Oncogene","url":"https://pubmed.ncbi.nlm.nih.gov/34750518","citation_count":12,"is_preprint":false},{"pmid":"33453238","id":"PMC_33453238","title":"MICAL2 regulates myofibroblasts differentiation in epidural fibrosis via SRF/MRTF-A signaling pathway.","date":"2021","source":"Life sciences","url":"https://pubmed.ncbi.nlm.nih.gov/33453238","citation_count":11,"is_preprint":false},{"pmid":"37906571","id":"PMC_37906571","title":"DNA methylation alterations of ADCY5, MICAL2, and PLEKHG2 during the developmental stage of cryptogenic hepatocellular carcinoma.","date":"2023","source":"Hepatology research : the official journal of the Japan Society of Hepatology","url":"https://pubmed.ncbi.nlm.nih.gov/37906571","citation_count":7,"is_preprint":false},{"pmid":"39745352","id":"PMC_39745352","title":"MICAL2 Promotes Pancreatic Cancer Growth and Metastasis.","date":"2025","source":"Cancer research","url":"https://pubmed.ncbi.nlm.nih.gov/39745352","citation_count":4,"is_preprint":false},{"pmid":"34946600","id":"PMC_34946600","title":"Enriching the Arsenal of Pharmacological Tools against MICAL2.","date":"2021","source":"Molecules (Basel, Switzerland)","url":"https://pubmed.ncbi.nlm.nih.gov/34946600","citation_count":4,"is_preprint":false},{"pmid":"38137053","id":"PMC_38137053","title":"Gas6-Axl Signaling Induces SRF/MRTF-A Gene Transcription via MICAL2.","date":"2023","source":"Genes","url":"https://pubmed.ncbi.nlm.nih.gov/38137053","citation_count":3,"is_preprint":false},{"pmid":"34264264","id":"PMC_34264264","title":"MICAL2 fine-tunes Arp2/3 for actin branching.","date":"2021","source":"The Journal of cell biology","url":"https://pubmed.ncbi.nlm.nih.gov/34264264","citation_count":2,"is_preprint":false},{"pmid":"38979336","id":"PMC_38979336","title":"MICAL2 Is a Super Enhancer Associated Gene that Promotes Pancreatic Cancer Growth and Metastasis.","date":"2024","source":"bioRxiv : the preprint server for biology","url":"https://pubmed.ncbi.nlm.nih.gov/38979336","citation_count":1,"is_preprint":false},{"pmid":"40240704","id":"PMC_40240704","title":"The role of MICAL2 in cancer progression: mechanisms, challenges, and therapeutic potential.","date":"2025","source":"Human cell","url":"https://pubmed.ncbi.nlm.nih.gov/40240704","citation_count":0,"is_preprint":false},{"pmid":"41550487","id":"PMC_41550487","title":"Identification of COL8A2, MICAL2, and TNFSF10 as potential biomarkers associated with both exercise response and osteoarthritis: a multi-omics integration study.","date":"2026","source":"3 Biotech","url":"https://pubmed.ncbi.nlm.nih.gov/41550487","citation_count":0,"is_preprint":false},{"pmid":"41797580","id":"PMC_41797580","title":"Endosomal actin attenuation and fission are regulated by MICAL2.","date":"2026","source":"Journal of cell science","url":"https://pubmed.ncbi.nlm.nih.gov/41797580","citation_count":0,"is_preprint":false},{"pmid":"41832266","id":"PMC_41832266","title":"LINC-AC092535.5 regulates MICAL2 mRNA level to inhibit p53-mediated ferroptosis in nasopharyngeal carcinoma.","date":"2026","source":"Oncogene","url":"https://pubmed.ncbi.nlm.nih.gov/41832266","citation_count":0,"is_preprint":false},{"pmid":"40822859","id":"PMC_40822859","title":"LncRNA MYO16-AS1 and MICAL2 axis sustains proliferation and migration in ovarian cancer cells and unveils a therapeutic vulnerability in patient-derived tumor organoids.","date":"2025","source":"Non-coding RNA research","url":"https://pubmed.ncbi.nlm.nih.gov/40822859","citation_count":0,"is_preprint":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":17093,"output_tokens":4961,"usd":0.062847},"stage2":{"model":"claude-opus-4-6","input_tokens":8484,"output_tokens":3493,"usd":0.194617},"total_usd":0.257464,"stage1_batch_id":"msgbatch_01Mgbec4vM6c9vXht7JVJzss","stage2_batch_id":"msgbatch_01JkuuH5RB2BdJNsgnhjbC6s","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2014,\n      \"finding\": \"MICAL-2 mediates redox-dependent depolymerization of nuclear actin by oxidizing actin subunits, which decreases nuclear G-actin levels, prevents MRTF-A nuclear export, and thereby activates SRF/MRTF-A-dependent gene transcription in response to NGF and serum. MICAL-2 was also identified as a target of the SRF/MRTF-A inhibitor CCG-1423.\",\n      \"method\": \"Knockdown/overexpression in cells, nuclear fractionation, live-cell imaging of nuclear actin dynamics, small-molecule inhibition (CCG-1423)\",\n      \"journal\": \"Cell\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — multiple orthogonal methods, highly cited foundational study replicated by subsequent labs\",\n      \"pmids\": [\"24440334\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"The MICAL-2 monooxygenase domain is a flavin-dependent enzyme that uses NADPH (preferentially, via the proR hydride) to reduce its flavin; this reductive half-reaction is strongly stimulated by F-actin, consistent with the Class A aromatic hydroxylase regulatory mechanism where substrate binding promotes flavin reduction and prevents wasteful H2O2 production.\",\n      \"method\": \"In vitro enzymatic assay with purified monooxygenase domain, kinetic isotope effect measurement with deuterium-labeled NADPH, stopped-flow kinetics with and without F-actin\",\n      \"journal\": \"Biochemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 — rigorous in vitro enzymology with purified protein, isotope labeling, and kinetic analysis\",\n      \"pmids\": [\"23927065\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"MICAL2 mediates methionine oxidation of ARP3B, a specific subunit of the ARP2/3 complex, thereby destabilizing ARP2/3 complexes and leading to disassembly of branched actin filaments.\",\n      \"method\": \"Biochemical reconstitution and functional analysis of ARP2/3 isoform-specific regulation (reported as a commentary on primary data from Galloni et al.)\",\n      \"journal\": \"The Journal of cell biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1 method (methionine oxidation assay) described in referenced primary paper; citation is a commentary summarizing that work\",\n      \"pmids\": [\"34264264\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"MICAL2 physically interacts with p53, retains it in the cytoplasm, and oxidizes p53 at methionine 40 and methionine 160, which promotes p53 ubiquitin-mediated degradation and reduces p53 tumor-suppressive function in colorectal cancer cells.\",\n      \"method\": \"Co-immunoprecipitation, reverse-phase nano ESI-LCMS mass spectrometry to detect methionine oxidation, immunofluorescence of p53 localization, ubiquitination assay, p53+/+ vs p53-/- cell comparison, in vivo xenograft\",\n      \"journal\": \"Theranostics\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 — mass spectrometry identification of specific oxidized residues plus functional epistasis in p53-null cells and in vivo confirmation\",\n      \"pmids\": [\"30555547\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"ARG (Abelson-related gene) kinase interacts with MICAL2 and phosphorylates it at Tyr445, Tyr463, and Tyr488; phosphorylation at Tyr445 and Tyr463 (but not Tyr488) enhances MICAL2-mediated F-actin disassembly, which directly oxidizes methionine 44 and 47 of F-actin.\",\n      \"method\": \"Direct phosphorylation assay, mass spectrometry confirmation of phosphorylation sites, non-phosphorylatable phenylalanine substitution mutants tested in F-actin disassembly assays and cell proliferation rescue experiments\",\n      \"journal\": \"Oncogene\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 — in vitro phosphorylation assay with MS validation, site-specific mutagenesis with functional readout\",\n      \"pmids\": [\"34750518\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"MICAL2 knockdown in human cancer cells causes mesenchymal-to-epithelial transition and loss of motility/invasion, while re-expression of MICAL2 cDNA in depleted cells induces epithelial-to-mesenchymal transition, demonstrating MICAL2 is a direct regulator of EMT.\",\n      \"method\": \"siRNA/shRNA knockdown, cDNA rescue, cell morphology, migration and invasion assays\",\n      \"journal\": \"Oncotarget\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — clean KO/rescue with defined phenotype, but single lab without structural validation\",\n      \"pmids\": [\"26689989\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"MICAL2 maintains EGFR protein stability by delaying EGFR degradation in a Rac1-dependent manner, leading to sustained EGFR/P38/HSP27 and P38/MMP9 signaling and promotion of breast cancer cell migration.\",\n      \"method\": \"Gene overexpression and knockdown, Western blotting for EGFR degradation kinetics, Rac1 pull-down activity assay, wound-healing migration assay\",\n      \"journal\": \"Acta physiologica\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2–3 — multiple methods in one lab demonstrating Rac1-dependent mechanism, but no reconstitution\",\n      \"pmids\": [\"28719045\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"MICAL2 is a nucleocytoplasmic shuttling protein; its nuclear export depends on myosin-9 interaction and its C-terminal fragment. Cytoplasmic (but not nuclear-restricted) MICAL2 promotes tumor malignancy through AKT and myosin-9 pathways, and nuclear export inhibitors or myosin-9 inhibitors reduce MICAL2-driven tumor promotion.\",\n      \"method\": \"Subcellular fractionation, nuclear export inhibitor treatment, myosin-9 siRNA knockdown, domain-deletion constructs (MICAL2-ΔC), in vitro and in vivo tumor assays\",\n      \"journal\": \"Cancer letters\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — localization tied to functional consequence with domain mapping, single lab\",\n      \"pmids\": [\"32360180\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"MICAL2 promotes gastric cancer cell migration by inducing MRTF-A nuclear translocation in response to EGF/serum (via ROS generation), which subsequently activates CDC42 and increases MMP9 expression; silencing MICAL2 blocks CDC42 activation and MRTF-A nuclear retention.\",\n      \"method\": \"siRNA knockdown, overexpression, DCFH-DA ROS staining, nuclear/cytoplasmic fractionation, CDC42 pull-down activity assay, qPCR/Western blot for MMP9\",\n      \"journal\": \"Frontiers in molecular biosciences\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — multiple orthogonal assays in single lab placing MICAL2 upstream of MRTF-A and CDC42\",\n      \"pmids\": [\"33842533\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"MICAL2 promotes gastric cancer cell proliferation through two parallel mechanisms: ROS generation and Cdc42 activation, both of which independently drive YAP dephosphorylation and YAP nuclear translocation; ROS scavenging (NAC/tempol) reverses MICAL2-mediated YAP activation.\",\n      \"method\": \"Overexpression/knockdown, ROS measurement, p-YAP/YAP ratio by Western blot, Cdc42 pull-down, nuclear/cytoplasmic YAP fractionation, ROS scavenger rescue experiments\",\n      \"journal\": \"Oxidative medicine and cellular longevity\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — pharmacological rescue orthogonally validates ROS mechanism; single lab\",\n      \"pmids\": [\"34650666\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"MICAL2 promotes E-cadherin ubiquitination and degradation in a Cdc42-dependent manner, disrupting the E-cadherin/β-catenin complex and releasing β-catenin for nuclear translocation to drive gastric cancer cell migration; GSK3β inhibition rescues the MICAL2 knockdown migratory phenotype.\",\n      \"method\": \"Knockdown, co-immunoprecipitation of E-cadherin/β-catenin complex, nuclear/cytoplasmic fractionation, ubiquitination assay, Cdc42 pull-down, GSK3β inhibitor (LiCl) rescue\",\n      \"journal\": \"Cell communication and signaling\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — reciprocal Co-IP plus epistasis with LiCl rescue; single lab\",\n      \"pmids\": [\"36064550\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"MICAL2 mediates myofibroblast differentiation in a SRF/MRTF-A-dependent manner: MICAL2 knockdown inhibits MRTF-A nuclear translocation in TGF-β1-stimulated fibroblasts and attenuates α-SMA, collagen-1, and fibronectin expression as well as epidural fibrosis in vivo.\",\n      \"method\": \"shRNA lentiviral knockdown, immunofluorescence of MRTF-A localization, Western blot for fibrosis markers, in vivo rat laminectomy model\",\n      \"journal\": \"Life sciences\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — in vivo and in vitro epistasis placing MICAL2 upstream of MRTF-A nuclear translocation; single lab\",\n      \"pmids\": [\"33453238\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"MICAL2 is essential for myogenic lineage commitment: MICAL2 expression increases during skeletal, smooth, and cardiac muscle differentiation, it localizes to the nucleus of regenerating muscle fibers, and in vivo CRISPR-Cas9 deletion of Mical2 causes actin defects and loss of skeletal muscle homeostasis/functionality.\",\n      \"method\": \"In vivo Cas9/gRNA delivery, immunofluorescence localization, differentiation assays of adult stem cells and PSCs, muscle functional assessment\",\n      \"journal\": \"Cell death & disease\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — in vivo CRISPR loss-of-function with defined structural phenotype; single lab\",\n      \"pmids\": [\"32811811\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"MICAL2 is required for endothelial cell response to VEGF: MICAL2 enters the p130Cas interactome in response to VEGF in HUVECs, and MICAL2 KD disables EC VEGF response, viability, and motility; MICAL2 is selectively expressed in neo-angiogenic (but not normal) capillary endothelia in human tumors.\",\n      \"method\": \"siRNA knockdown, CCG-1423 pharmacological inhibition, whole-genome gene expression profiling, immunohistochemistry of human tumor sections, proteomic interactome (p130Cas)\",\n      \"journal\": \"Biochimica et biophysica acta. Molecular basis of disease\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2–3 — interactome and KD with functional readout; single lab, no reconstitution\",\n      \"pmids\": [\"31004710\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"Gas6/Axl receptor tyrosine kinase signaling activates SRF/MRTF-A-dependent transcription through MICAL2: Axl inhibition blocks serum-induced SRF/MRTF-A gene expression, Gas6/Axl-induced transcription requires MICAL2, and Gas6/Axl signaling promotes nuclear localization of MICAL2.\",\n      \"method\": \"Axl inhibitor treatment, MICAL2 siRNA knockdown, nuclear MICAL2 localization imaging, gene expression analysis of SRF/MRTF-A target genes, cell invasion assay\",\n      \"journal\": \"Genes\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — epistasis placing MICAL2 downstream of Gas6/Axl with functional rescue; single lab\",\n      \"pmids\": [\"38137053\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"MICAL2 interacts with TGF receptor type I (TGFRI) and activates TGF-β/p-Smad2/EMT-like signaling to promote glioblastoma cell proliferation and migration.\",\n      \"method\": \"Co-immunoprecipitation of MICAL2-TGFRI interaction, knockdown of MICAL2, Western blot for p-Smad2, in vitro and in vivo (nude mouse) proliferation/invasion assays\",\n      \"journal\": \"Frontiers in oncology\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 — single Co-IP with partial mechanistic follow-up; single lab\",\n      \"pmids\": [\"34868922\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2026,\n      \"finding\": \"MICAL2 acts as a constitutively active actin-regulatory monooxygenase at endosomes: MICAL2 depletion or inhibition of its monooxygenase activity causes a substantial increase in Arp2/3-mediated branched actin at endosomes, impairing endosome fission and clathrin-dependent cargo recycling to the plasma membrane.\",\n      \"method\": \"siRNA knockdown, monooxygenase inhibitor treatment, fluorescence imaging of branched actin at endosomes, endosome fission and cargo recycling functional assays\",\n      \"journal\": \"Journal of cell science\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — genetic and pharmacological loss-of-function with defined organelle-level phenotype, monooxygenase-specific inhibitor controls\",\n      \"pmids\": [\"41797580\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"MICAL2 facilitates p53 ubiquitination and degradation in NPC cells by recruiting the E3 ubiquitin ligase MDM2 to p53, in addition to influencing nuclear translocation of p53, thereby inhibiting ferroptosis and promoting tumor progression.\",\n      \"method\": \"Co-immunoprecipitation of MICAL2-MDM2-p53 complex, ubiquitination assay, nuclear translocation imaging, transcriptome sequencing, RACE experiments\",\n      \"journal\": \"Oncogene\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — Co-IP demonstrating MDM2 recruitment plus ubiquitination assay; single lab\",\n      \"pmids\": [\"41832266\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"MICAL2 activates ERK1/2 signaling in pulmonary arterial smooth muscle cells to promote proliferation; miR-205-5p suppresses this by targeting the MICAL2 3'UTR, and ERK1/2 inhibition blocks MICAL2-mediated proliferation.\",\n      \"method\": \"Luciferase reporter assay for miR-205-5p targeting of MICAL2 3'UTR, MICAL2 overexpression, ERK1/2 inhibitor rescue, cell proliferation assay\",\n      \"journal\": \"Microvascular research\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 — single lab, pathway placement via inhibitor only, no direct mechanistic link between MICAL2 catalytic activity and ERK activation\",\n      \"pmids\": [\"30853343\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"MICAL2 promotes ERK1/2 and AKT activation and macropinocytosis in pancreatic ductal adenocarcinoma cells, and upregulates KRAS and EMT signaling pathways; MRTF-B (but not MRTF-A) phenocopies MICAL2-driven in vivo tumor growth and metastasis.\",\n      \"method\": \"Loss- and gain-of-function experiments, Western blot for ERK1/2/AKT phosphorylation, macropinocytosis assay, in vivo xenograft/metastasis models, transcriptional analysis\",\n      \"journal\": \"Cancer research\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — multiple orthogonal assays in vitro and in vivo; single lab with peer-reviewed publication\",\n      \"pmids\": [\"39745352\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"MICAL2 is a nuclear and cytoplasmic flavin-dependent monooxygenase that uses NADPH (stimulated by F-actin binding) to oxidize specific methionine residues on F-actin (Met44/47) and ARP3B, thereby driving actin depolymerization and branched-actin disassembly; in the nucleus this reduces G-actin levels to retain MRTF-A and activate SRF/MRTF-A transcription (downstream of NGF, serum, and Gas6/Axl signaling), while in the cytoplasm it stabilizes EGFR, activates Rac1/Cdc42/RhoA, promotes YAP nuclear translocation via ROS, oxidizes and destabilizes p53 (recruiting MDM2 for ubiquitination), facilitates endosome fission by attenuating branched actin, and is itself regulated by ARG kinase phosphorylation at Tyr445/463 and myosin-9-dependent nuclear export.\"\n}\n```","stage2_raw":"```json\n{\n  \"mechanistic_narrative\": \"MICAL2 is a flavin-dependent monooxygenase that oxidizes specific methionine residues on actin and actin-regulatory proteins, linking redox-driven cytoskeletal remodeling to transcriptional control, endosomal trafficking, and signal transduction. Its NADPH-consuming reductive half-reaction is allosterically stimulated by F-actin binding, and it directly oxidizes Met44/Met47 on F-actin to drive depolymerization — an activity enhanced by ARG kinase phosphorylation at Tyr445/463 — and also oxidizes ARP3B to destabilize branched actin networks required for endosome fission and clathrin-dependent cargo recycling [PMID:23927065, PMID:34750518, PMID:34264264, PMID:41797580]. In the nucleus, MICAL2-mediated actin oxidation reduces G-actin levels, retaining MRTF-A to activate SRF/MRTF-A-dependent transcription downstream of NGF, serum, TGF-β1, and Gas6/Axl signaling, thereby regulating programs including EMT, myofibroblast differentiation, and myogenic commitment [PMID:24440334, PMID:33453238, PMID:38137053, PMID:32811811]. MICAL2 also oxidizes p53 at Met40/Met160, promoting MDM2-dependent ubiquitination and degradation of p53, and activates ROS/Cdc42 signaling to drive YAP nuclear translocation, E-cadherin degradation, and β-catenin release [PMID:30555547, PMID:41832266, PMID:34650666, PMID:36064550].\",\n  \"teleology\": [\n    {\n      \"year\": 2013,\n      \"claim\": \"Establishing MICAL2 as a bona fide flavin-dependent monooxygenase with an F-actin-gated catalytic cycle resolved how MICAL2 avoids futile ROS production and couples NADPH consumption to its substrate.\",\n      \"evidence\": \"Purified monooxygenase domain kinetics with stopped-flow, deuterium-labeled NADPH isotope effects, and F-actin stimulation in vitro\",\n      \"pmids\": [\"23927065\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"No structural basis for F-actin-induced allosteric activation\", \"Product (oxygenated actin) characterization incomplete at this stage\", \"Regulation of the monooxygenase domain by other MICAL2 domains not addressed\"]\n    },\n    {\n      \"year\": 2014,\n      \"claim\": \"Demonstrating that MICAL2 oxidizes nuclear actin to deplete G-actin and retain MRTF-A in the nucleus established a direct redox-to-transcription axis, answering how SRF/MRTF-A programs are activated without classical Rho-driven actin dynamics.\",\n      \"evidence\": \"Knockdown/overexpression in cells, nuclear fractionation, live-cell imaging, CCG-1423 inhibition\",\n      \"pmids\": [\"24440334\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Identity of nuclear actin methionine residues oxidized by MICAL2 not shown\", \"How MICAL2 itself enters the nucleus was unknown\", \"Relative contribution vs. MICAL1/MICAL3 in nuclear actin remodeling not resolved\"]\n    },\n    {\n      \"year\": 2016,\n      \"claim\": \"Showing that MICAL2 depletion reverses EMT and re-expression restores it placed the enzyme as a functional driver of epithelial–mesenchymal plasticity, not merely a bystander.\",\n      \"evidence\": \"siRNA/shRNA knockdown and cDNA rescue with morphology, migration, and invasion assays in cancer cells\",\n      \"pmids\": [\"26689989\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Whether EMT regulation requires monooxygenase activity or scaffolding was not separated\", \"No direct actin oxidation measurement in this context\", \"Single-lab finding\"]\n    },\n    {\n      \"year\": 2017,\n      \"claim\": \"Identifying MICAL2 as a stabilizer of EGFR through Rac1-dependent delay of receptor degradation extended its role beyond actin oxidation to receptor tyrosine kinase signaling.\",\n      \"evidence\": \"Overexpression/knockdown with EGFR degradation kinetics and Rac1 pull-down in breast cancer cells\",\n      \"pmids\": [\"28719045\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Whether MICAL2 monooxygenase activity is required for EGFR stabilization was not tested\", \"No reconstitution of MICAL2–EGFR–Rac1 axis\", \"Single lab\"]\n    },\n    {\n      \"year\": 2018,\n      \"claim\": \"Identifying p53 Met40/Met160 as direct MICAL2 oxidation targets that promote ubiquitin-mediated p53 degradation revealed a non-actin substrate and a tumor-suppressor-inactivation mechanism.\",\n      \"evidence\": \"Co-IP, nano ESI-LCMS for methionine oxidation sites, ubiquitination assay, p53-null epistasis, xenograft\",\n      \"pmids\": [\"30555547\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Whether oxidation alone suffices for degradation or requires additional cofactors was unclear\", \"E3 ligase identity not identified in this study\", \"Specificity among MICAL family members not tested\"]\n    },\n    {\n      \"year\": 2019,\n      \"claim\": \"Placing MICAL2 in the VEGF-responsive p130Cas interactome in endothelial cells and showing selective expression in neo-angiogenic tumor capillaries defined a vascular-specific function.\",\n      \"evidence\": \"siRNA knockdown in HUVECs, proteomic interactome, immunohistochemistry of human tumor vasculature\",\n      \"pmids\": [\"31004710\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct enzymatic substrates in the endothelial VEGF response not identified\", \"Interactome role of p130Cas–MICAL2 interaction not mechanistically resolved\", \"Single lab\"]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"Defining MICAL2 as a nucleocytoplasmic shuttling protein whose export depends on myosin-9 and whose cytoplasmic (not nuclear) pool drives tumorigenesis resolved how its subcellular distribution gates distinct outputs.\",\n      \"evidence\": \"Subcellular fractionation, nuclear export inhibitors, myosin-9 siRNA, domain-deletion constructs, in vivo tumor assays\",\n      \"pmids\": [\"32811811\", \"32360180\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Nuclear import signal/mechanism not characterized\", \"Whether nuclear vs. cytoplasmic pools have distinct substrates beyond actin was unknown\", \"Myosin-9 interaction mode (direct or bridged) not determined\"]\n    },\n    {\n      \"year\": 2021,\n      \"claim\": \"Multiple converging studies established that MICAL2 oxidizes ARP3B to disassemble branched actin, is activated by ARG kinase phosphorylation at Tyr445/463, and signals through ROS/Cdc42 to activate YAP nuclear translocation and MRTF-A, integrating upstream kinase regulation with downstream transcriptional effectors.\",\n      \"evidence\": \"Biochemical ARP3B oxidation assay, ARG kinase phosphorylation with MS and mutagenesis, ROS scavenger rescue of YAP activation, Cdc42 pull-down, in vivo fibrosis model\",\n      \"pmids\": [\"34264264\", \"34750518\", \"34650666\", \"33842533\", \"33453238\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Whether ARG-mediated phosphorylation affects MICAL2 substrate selectivity (actin vs. non-actin) was not tested\", \"Structural basis for Tyr445/463 activation of monooxygenase domain unknown\", \"Relative contribution of direct actin oxidation vs. ROS generation to downstream signaling not quantified\"]\n    },\n    {\n      \"year\": 2022,\n      \"claim\": \"Demonstrating that MICAL2 promotes E-cadherin ubiquitination and β-catenin nuclear translocation via Cdc42 connected its actin-regulatory activity to adherens junction disassembly and Wnt-like signaling.\",\n      \"evidence\": \"Reciprocal Co-IP of E-cadherin/β-catenin, ubiquitination assay, Cdc42 pull-down, GSK3β inhibitor rescue\",\n      \"pmids\": [\"36064550\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"E3 ligase mediating E-cadherin ubiquitination downstream of MICAL2 not identified\", \"Whether MICAL2 directly oxidizes E-cadherin or acts indirectly through actin not resolved\", \"Single lab\"]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Placing Gas6/Axl upstream of MICAL2 nuclear localization and SRF/MRTF-A transcription identified a new receptor pathway that converges on MICAL2's nuclear actin-remodeling function.\",\n      \"evidence\": \"Axl inhibitor treatment, MICAL2 siRNA epistasis, nuclear MICAL2 imaging, SRF/MRTF-A target gene expression\",\n      \"pmids\": [\"38137053\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Phosphorylation or other post-translational modification linking Axl to MICAL2 nuclear import not identified\", \"Whether Axl acts through ARG kinase to phosphorylate MICAL2 not tested\", \"Single lab\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Identifying MDM2 as the E3 ligase recruited by MICAL2 to ubiquitinate oxidized p53 completed the mechanistic pathway from MICAL2-mediated p53 oxidation to proteasomal degradation and ferroptosis inhibition.\",\n      \"evidence\": \"Co-IP of MICAL2–MDM2–p53 ternary complex, ubiquitination assay, transcriptome sequencing in NPC cells\",\n      \"pmids\": [\"41832266\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Whether MICAL2 oxidation of p53 is prerequisite for MDM2 binding or operates in parallel not dissected\", \"Structural basis of MICAL2–MDM2 interaction unknown\", \"Single lab, single cancer type\"]\n    },\n    {\n      \"year\": 2026,\n      \"claim\": \"Demonstrating that MICAL2 constitutively removes branched actin from endosomes to enable fission and cargo recycling established its first non-nuclear, non-migratory housekeeping function in membrane trafficking.\",\n      \"evidence\": \"siRNA and monooxygenase inhibitor treatment, fluorescence imaging of endosomal branched actin, fission and recycling assays\",\n      \"pmids\": [\"41797580\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Whether MICAL2 is recruited to endosomes via specific adaptors or acts diffusely not known\", \"Redundancy with MICAL1 or MICAL3 at endosomes not tested\", \"Impact on non-clathrin cargo recycling pathways not assessed\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"A comprehensive structural model of full-length MICAL2 explaining how domain architecture, post-translational modifications, and subcellular targeting coordinately regulate substrate selectivity (actin vs. ARP3B vs. p53) is lacking.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Low\",\n      \"gaps\": [\"No full-length MICAL2 structure available\", \"Quantitative partitioning of ROS-mediated vs. direct methionine-oxidation signaling not determined\", \"In vivo genetic models of catalytic-dead vs. null alleles needed to separate enzymatic from scaffolding functions\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0016491\", \"supporting_discovery_ids\": [0, 1, 2, 3, 4, 16]},\n      {\"term_id\": \"GO:0140096\", \"supporting_discovery_ids\": [3, 4, 17]},\n      {\"term_id\": \"GO:0008092\", \"supporting_discovery_ids\": [0, 1, 4, 16]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005634\", \"supporting_discovery_ids\": [0, 7, 12, 14]},\n      {\"term_id\": \"GO:0005829\", \"supporting_discovery_ids\": [3, 7]},\n      {\"term_id\": \"GO:0005768\", \"supporting_discovery_ids\": [16]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-74160\", \"supporting_discovery_ids\": [0, 8, 11, 14]},\n      {\"term_id\": \"R-HSA-162582\", \"supporting_discovery_ids\": [6, 9, 10, 19]},\n      {\"term_id\": \"R-HSA-5653656\", \"supporting_discovery_ids\": [16]},\n      {\"term_id\": \"R-HSA-5357801\", \"supporting_discovery_ids\": [3, 17]}\n    ],\n    \"complexes\": [],\n    \"partners\": [\n      \"ABL2\",\n      \"MYH9\",\n      \"TP53\",\n      \"MDM2\",\n      \"ACTR3B\",\n      \"MRTFA\",\n      \"AXL\",\n      \"BCAR1\"\n    ],\n    \"other_free_text\": []\n  }\n}\n```"}