Affinage

EVC2

Limbin · UniProt Q86UK5

Length
1308 aa
Mass
147.9 kDa
Annotated
2026-04-28
38 papers in source corpus 11 papers cited in narrative 11 extracted findings

Mechanistic narrative

Synthesis pass · prose summary of the discoveries below

EVC2 is a ciliary transmembrane protein that functions as a core positive transducer of Hedgehog (Hh) signaling, linking activated Smoothened to downstream Gli transcription factor processing at primary cilia. EVC2 forms an obligate heterodimeric complex with EVC — each partner required for the other's ciliary localization and protein stability — and upon Hh stimulation, phosphorylated Smoothened recruits this complex at a specialized ciliary microdomain (the EvC zone), where it promotes Sufu/Gli dissociation and Gli trafficking to the ciliary tip (PMID:22981989, PMID:23026747, PMID:22986504). The EvC zone positioning of EVC-EVC2 is anchored by the EFCAB7-IQCE module binding two motifs in the EVC2 C-terminal disordered region, and complex turnover is regulated by destabilizing monoubiquitination and stabilizing SUMO3 modification (PMID:24582806, PMID:37576597). Loss-of-function mutations in EVC2 cause Ellis–van Creveld syndrome, characterized by skeletal dwarfism partly driven by ectopic FGF18 upregulation, while dominant-negative C-terminal mutations underlie Weyers acrofacial dysostosis (PMID:19810119, PMID:28027321).

Mechanistic history

Synthesis pass · year-by-year structured walk · 9 steps
  1. 2009 Medium

    Distinguishing dominant-negative from loss-of-function EVC2 alleles established that the C-terminal region disrupted in Weyers acrofacial dysostosis exerts a distinct pathomechanism from Ellis–van Creveld truncation mutations, linking specific EVC2 domains to Hh signaling output.

    Evidence Ectopic expression of Weyers exon 22 missense variants versus EvC-syndrome truncation constructs in NIH 3T3 Hh reporter assay

    PMID:19810119

    Open questions at the time
    • Only a single reporter cell line tested; no endogenous locus validation
    • Mechanism of dominant-negative action not resolved
  2. 2011 High

    Identification of EVC2 as a transmembrane protein that directly binds EVC and co-dependently localizes to the basal body/primary cilium established the EVC-EVC2 complex as a functional unit required for Hh pathway activation.

    Evidence Yeast two-hybrid confirmed by co-IP; topology analysis; co-dependent ciliary localization by immunofluorescence; Smo agonist functional assay

    PMID:21356043

    Open questions at the time
    • Whether EVC2 nuclear localization has a signaling role remained unresolved
    • Stoichiometry and structural basis of the EVC-EVC2 complex unknown
  3. 2012 High

    Three concurrent studies placed EVC-EVC2 in the Hh pathway between phosphorylated Smoothened and Sufu/Gli, showing that Smo phosphorylation-dependent recruitment of EVC2 to a defined ciliary EvC zone is necessary for Gli3 trafficking to cilia tips and Sufu/Gli dissociation.

    Evidence Co-IP of Smo-EVC2, epistasis with Sufu−/− and Kif3a−/− cells, dominant-negative EvC zone displacement mutants, Gli3 ciliary tip assays in EVC2-deficient chondrocytes from KO mice

    PMID:22981989 PMID:22986504 PMID:23026747

    Open questions at the time
    • Biochemical mechanism by which EVC-EVC2 promotes Sufu/Gli dissociation undefined
    • Whether EVC2 directly contacts Gli or Sufu unknown
  4. 2014 High

    Discovery that the EFCAB7-IQCE module anchors EVC-EVC2 to the EvC zone through a C-terminal disordered region of EVC2 explained how spatial restriction of the complex enables signaling and why Weyers deletions of that region act as dominant negatives.

    Evidence Co-IP mapping of EFCAB7-EVC2 binding domain, shRNA knockdown of EFCAB7 causing EVC-EVC2 mislocalization and impaired GLI2 activation

    PMID:24582806

    Open questions at the time
    • Structural details of EFCAB7-EVC2 interaction absent
    • Role of IQCE beyond scaffolding not elucidated
  5. 2015 High

    Conditional knockout studies defined tissue-specific requirements: EVC2 is essential in cartilage for skeletal growth and in neural crest for incisor development, but dispensable in osteoblasts, revealing context-dependent Hh transduction needs.

    Evidence Conventional and conditional Evc2 KO mice with cartilage-, neural crest-, and osteoblast-specific Cre drivers; Hh pathway and localization assays

    PMID:26219237

    Open questions at the time
    • Whether other signaling pathways compensate in osteoblasts is unknown
    • Heart and other organ phenotypes not thoroughly characterized
  6. 2016 High

    The finding that Evc2 loss in perichondrium upregulates Fgf18, and that heterozygous Fgf18 deletion partially rescues dwarfism, identified FGF pathway hyperactivation as a key downstream pathogenic effector of EVC2 deficiency in skeletal growth.

    Evidence Evc2 mutant mice crossed with Fgf18 heterozygotes; in vivo and in vitro growth plate cultures with FGF signaling readouts

    PMID:28027321

    Open questions at the time
    • Whether Fgf18 upregulation is directly due to reduced Hh output or a parallel mechanism is unclear
    • Rescue was partial — additional pathogenic pathways likely contribute
  7. 2017 Medium

    Dental mesenchyme-specific deletion showed that EVC2's role in Hh-dependent stem cell homeostasis within the dental mesenchyme non-cell-autonomously drives ameloblast maturation, extending the pathway's tissue requirement beyond bone.

    Evidence Conditional KO mice with dental mesenchyme-specific Cre; histology and ameloblast marker analysis

    PMID:28081373

    Open questions at the time
    • Single lab; independent replication pending
    • Molecular mediators of the non-cell-autonomous signal to ameloblasts unidentified
  8. 2023 High

    Post-translational regulation of the EVC-EVC2 complex was defined: monoubiquitination destabilizes the complex while SUMO3 modification enhances EvC zone accumulation, and two distinct EFCAB7-binding motifs within EVC2 are both required for EvC zone targeting; USP7 was identified as a novel interactor.

    Evidence Endogenous EVC interactome by mass spectrometry, ubiquitination and SUMOylation biochemical assays, domain mapping with ciliary localization readout in Evc-null cells

    PMID:37576597

    Open questions at the time
    • Whether USP7 deubiquitinates EVC-EVC2 directly not shown
    • SUMO3 ligase and deubiquitinase identities remain unknown
    • Functional Hh signaling consequences of SUMO/ubiquitin perturbation not measured
  9. 2025 Medium

    EVC2 was found to be aberrantly overexpressed in AML subsets and to drive leukemogenesis through MYC pathway activation independently of Hh signaling, revealing a non-canonical oncogenic function.

    Evidence shRNA/CRISPR KO in AML cell lines, in vivo AML progression assays, MYC pathway expression analysis, ChIP and chromatin interaction assays for AML1-ETO and ASXL1-mutant contexts

    PMID:41249566

    Open questions at the time
    • Novel finding not yet independently replicated
    • Mechanism linking EVC-EVC2 to MYC activation is undefined
    • Whether EVC2 transmembrane/ciliary topology is relevant in AML cells unclear

Open questions

Synthesis pass · forward-looking unresolved questions
  • The direct biochemical mechanism by which the EVC-EVC2 complex promotes Sufu/Gli dissociation remains unknown, and no structural model of the EVC-EVC2-EFCAB7-IQCE assembly or its interface with Smoothened exists.
  • No reconstituted in vitro system demonstrating EVC-EVC2 sufficiency for Sufu-Gli dissociation
  • No high-resolution structure of EVC-EVC2 or its EvC zone complex
  • Signaling role of nuclear EVC2 unresolved

Mechanism profile

Synthesis pass · controlled-vocabulary classification · explore literature graph →
Molecular activity
GO:0060090 molecular adaptor activity 4
Localization
GO:0005929 cilium 6 GO:0005886 plasma membrane 1
Pathway
R-HSA-162582 Signal Transduction 6 R-HSA-1266738 Developmental Biology 3
Partners
EFCAB7EVCIQCESMOUSP7
Complex memberships
EVC-EVC2 complexEVC-EVC2-EFCAB7-IQCE complex

Evidence

Reading pass · 11 per-paper findings extracted from the source corpus
Year Finding Method Journal Conf PMIDs
2012 Hedgehog agonists promote association between Smoothened (Smo) and EVC2; this Smo-EVC2 complex formation is spatially restricted to a distinct ciliary compartment called the EvC zone. Mutant EVC2 proteins that localize in cilia but are displaced from the EvC zone act as dominant inhibitors of Hh signaling, and disabling EVC2 blocks Hh signaling between Smo and the downstream regulators PKA and Suppressor of Fused, preventing Gli transcription factor activation. Co-immunoprecipitation, dominant-negative localization mutants, epistasis analysis with PKA and Sufu, live-cell imaging of ciliary localization Developmental cell High 22981989
2012 EVC and EVC2 are mutually required for localizing to primary cilia and for maintaining normal protein levels of each other. Smo co-precipitates with the EVC/EVC2 complex. In EVC2-deficient chondrocytes, Gli3 recruitment to cilia tips is reduced and Sufu/Gli3 dissociation is impaired after Hh activation, while Smo translocation to the cilium remains normal. Mouse knockout models, co-immunoprecipitation, immunofluorescence of cilia, Western blot of protein levels, SAG-stimulated Gli3 trafficking assay Human molecular genetics High 23026747
2012 EVC and EVC2 act downstream of Smo but upstream of Sufu to transduce the Hh signal. Hh stimulates binding of EVC/EVC2 to Smo dependent on phosphorylation of the Smo C-terminal intracellular tail. This binding is abolished in Kif3a-/- cilium-deficient cells, demonstrating that the interaction requires primary cilia. Loss of EVC/EVC2 does not affect Smo phosphorylation or ciliary localization but impedes Hh pathway activation by constitutively active Smo. Co-immunoprecipitation, epistasis with Sufu-/- cells and constitutively active Smo constructs, phosphorylation-dependent binding assays, Kif3a-/- cilium-deficient cell line Cell research High 22986504
2011 EVC2 is a positive regulator of the Hh signaling pathway essential for pathway activation in response to the Smo agonist purmorphamine. EVC2 and EVC interact directly (identified by yeast two-hybrid and confirmed by immunoprecipitation). Co-localization of EVC and EVC2 at the basal body and primary cilia is co-dependent: basal body/cilia localization requires co-transfection of both constructs. EVC2 is a transmembrane protein with extracellular N-terminus and intracellular C-terminus and is also found in the nucleus (full-length EVC2 but not EVC). Yeast two-hybrid, co-immunoprecipitation, immunofluorescence of primary cilia and basal body, subcellular fractionation/Western blot, topology analysis BMC biology High 21356043
2014 The EFCAB7-IQCE complex anchors EVC-EVC2 in a signaling microdomain at the base of cilia (EvC zone). EFCAB7 directly binds a C-terminal disordered region of EVC2 that is deleted in Weyers acrofacial dysostosis patients. EFCAB7 depletion causes mislocalization of EVC-EVC2 within cilia and impairs activation of the transcription factor GLI2, phenocopying the Weyers cellular defect. Co-immunoprecipitation, shRNA-mediated depletion, immunofluorescence of ciliary localization, GLI2 activation assay, evolutionary/bioinformatic analysis Developmental cell High 24582806
2009 Expression of Weyers acrofacial dysostosis EVC2 exon 22 missense variants (dominant mutations) in NIH 3T3 cells disrupts Hedgehog signal transduction, whereas expression of a truncated EVC2 protein mimicking an Ellis-van Creveld syndrome loss-of-function mutation does not impair Hh signaling in the same assay, consistent with the dominant-negative mechanism of Weyers mutations. Ectopic expression of murine EVC2 exon 22 variants in NIH 3T3 cells, Hh reporter assay Human mutation Medium 19810119
2015 Homozygous Evc2 knockout mice show no ciliary localization of EVC2 or EVC and display reduced Hedgehog signaling activity with associated skeletal and oral defects. Cartilage-specific disruption of Evc2 causes skeletal defects; neural crest-specific disruption causes defective incisor growth; osteoblast-specific disruption does not cause overt skeletal changes, defining tissue-specific requirements for EVC2 in mineralized tissue formation. Conditional and conventional knockout mouse generation (IRES-LacZ knock-in), immunofluorescence for ciliary localization, Hh signaling assays, tissue-specific Cre lines Genesis (New York, N.Y. : 2000) High 26219237
2016 Elevated FGF signaling, mainly due to increased Fgf18 expression upon inactivation of Evc2 in the perichondrium, critically contributes to limb dwarfism pathogenesis. Partial rescue of dwarfism is achieved by inactivation of one Fgf18 allele in Evc2 mutant mice, establishing FGF pathway upregulation as a downstream pathogenic mechanism in EVC2-deficient bone. Evc2 mutant mouse analysis, in vivo and in vitro growth plate cultures, FGF signaling assays, genetic rescue (Evc2 mut x Fgf18 het intercross) PLoS genetics High 28027321
2023 EVC-EVC2 complex stability and ciliary targeting are regulated by ubiquitin and SUMO modification. Monoubiquitination of EVC-EVC2 cytosolic tails reduces protein levels. SUMOylation with SUMO3 enhances EVC-EVC2 accumulation at the EvC zone, possibly via increased binding to the EFCAB7-IQCE complex. EvC zone targeting requires two separate EFCAB7-binding motifs within EVC2's Weyers-deleted peptide. An endogenous EVC interactome screen confirmed EVC2, IQCE, and EFCAB7 as main interactors and identified USP7 as a new interactor. Endogenous protein interactome (mass spectrometry), ubiquitination assays, SUMOylation assays, immunofluorescence of EvC zone localization, Evc-null cell lines, domain mapping Frontiers in cell and developmental biology High 37576597
2017 Dental mesenchymal-specific deletion of Evc2 phenocopies the hypomorphic enamel and tooth abnormalities of global Evc2 knockout mice, demonstrating that EVC2 function in dental mesenchymal cells (regulating dental mesenchymal stem cell homeostasis and odontoblast differentiation) is required for normal ameloblast maturation and enamel formation. Conditional knockout mice (dental mesenchyme-specific Cre), histology, ameloblast marker immunohistochemistry, preameloblast differentiation assays Journal of dental research Medium 28081373
2025 EVC and EVC2 are aberrantly overexpressed in a subset of AML and are essential for leukemogenic properties of AML cells. Loss of EVC/EVC2 impairs leukemia cell proliferation, promotes differentiation, and blocks AML progression in vivo. Mechanistically, the leukemogenic role of EVC/EVC2 is mediated through MYC pathway activation, independent of their canonical Hedgehog signaling function. Elevated EVC/EVC2 expression is associated with gained AML1-ETO occupancy or enhanced chromatin interactions at EVC/EVC2 promoter regions in t(8;21) or ASXL1-mutant AML. shRNA/CRISPR loss-of-function in AML cell lines, in vivo AML progression assay, MYC pathway gene expression analysis, chromatin immunoprecipitation/chromatin interaction assays, differentiation assays Leukemia Medium 41249566

Source papers

Stage 0 corpus · 38 papers · ranked by NIH iCite citations
Year Title Journal Citations PMID
2012 A Smoothened-Evc2 complex transduces the Hedgehog signal at primary cilia. Developmental cell 149 22981989
2012 The ciliary Evc/Evc2 complex interacts with Smo and controls Hedgehog pathway activity in chondrocytes by regulating Sufu/Gli3 dissociation and Gli3 trafficking in primary cilia. Human molecular genetics 93 23026747
2012 Smoothened transduces Hedgehog signal by forming a complex with Evc/Evc2. Cell research 86 22986504
2006 Sequencing EVC and EVC2 identifies mutations in two-thirds of Ellis-van Creveld syndrome patients. Human genetics 80 17024374
2002 A new gene, EVC2, is mutated in Ellis-van Creveld syndrome. Molecular genetics and metabolism 78 12468274
2014 EFCAB7 and IQCE regulate hedgehog signaling by tethering the EVC-EVC2 complex to the base of primary cilia. Developmental cell 77 24582806
2011 Evc2 is a positive modulator of Hedgehog signalling that interacts with Evc at the cilia membrane and is also found in the nucleus. BMC biology 75 21356043
2012 Novel and recurrent EVC and EVC2 mutations in Ellis-van Creveld syndrome and Weyers acrofacial dyostosis. European journal of medical genetics 59 23220543
2009 Widening the mutation spectrum of EVC and EVC2: ectopic expression of Weyer variants in NIH 3T3 fibroblasts disrupts Hedgehog signaling. Human mutation 52 19810119
2006 A novel heterozygous deletion in the EVC2 gene causes Weyers acrofacial dysostosis. Human genetics 40 16404586
2014 Deletion in the EVC2 gene causes chondrodysplastic dwarfism in Tyrolean Grey cattle. PloS one 28 24733244
2015 Generation of Evc2/Limbin global and conditional KO mice and its roles during mineralized tissue formation. Genesis (New York, N.Y. : 2000) 25 26219237
2011 Two novel heterozygous mutations of EVC2 cause a mild phenotype of Ellis-van Creveld syndrome in a Chinese family. American journal of medical genetics. Part A 20 21815252
2017 Ellis-van Creveld syndrome and profound deafness resulted by sequence variants in the EVC/EVC2 and TMC1 genes. Journal of genetics 19 29321360
2016 Elevated Fibroblast Growth Factor Signaling Is Critical for the Pathogenesis of the Dwarfism in Evc2/Limbin Mutant Mice. PLoS genetics 18 28027321
2017 Loss of Function of Evc2 in Dental Mesenchyme Leads to Hypomorphic Enamel. Journal of dental research 16 28081373
2017 The Role of Ellis-Van Creveld 2(EVC2) in Mice During Cranial Bone Development. Anatomical record (Hoboken, N.J. : 2007) 16 28950429
2018 A Ciliary Protein EVC2/LIMBIN Plays a Critical Role in the Skull Base for Mid-Facial Development. Frontiers in physiology 14 30410447
2016 Truncation and microdeletion of EVC/EVC2 with missense mutation of EFCAB7 in Ellis-van Creveld syndrome. Congenital anomalies 12 26748586
2016 Expression of Evc2 in craniofacial tissues and craniofacial bone defects in Evc2 knockout mouse. Archives of oral biology 11 27164562
1980 Change of H-2 antigens' expression on mouse leukaemia LBN/a-2 and LBN/b-3 cells in the course of serial transplantation. Journal of immunogenetics 9 7373065
2023 Establishing an objective clinical spectrum, genotype-phenotype correlations, and CRMP1 as a modifier in the Ellis-van Creveld syndrome: The first systematic review of EVC- and EVC2-associated conditions. Genetics in medicine open 8 39669252
2016 Novel homozygous mutations in the EVC and EVC2 genes in two consanguineous families segregating autosomal recessive Ellis-van Creveld syndrome. Clinical dysmorphology 8 26580685
2023 EVC-EVC2 complex stability and ciliary targeting are regulated by modification with ubiquitin and SUMO. Frontiers in cell and developmental biology 7 37576597
2012 Identification of one novel mutation in the EVC2 gene in a Chinese family with Ellis-van Creveld syndrome. Gene 7 23026208
2019 Novel deleterious mutation in MYO7A, TH and EVC2 in two Pakistani brothers with familial deafness. Pakistan journal of medical sciences 6 30881389
2022 Dental Anomalies in Ciliopathies: Lessons from Patients with BBS2, BBS7, and EVC2 Mutations. Genes 5 36672825
2021 Ellis-van Creveld syndrome novel pathogenic variant in the EVC2 gene a patient from Turkey. Clinical case reports 4 33936625
1976 DNA polymerases of murine LBN/b leukemic cells. Acta biochimica Polonica 3 59500
2023 Identification of Compound Heterozygous EVC2 Gene Variants in Two Mexican Families with Ellis-van Creveld Syndrome. Genes 2 37107645
2023 Prenatal whole exome sequencing identified two rare compound heterozygous variants in EVC2 causing Ellis-van Creveld syndrome. Molecular genetics & genomic medicine 2 37485807
2025 Neural crest-specific disruption of Evc2 provides an animal model to study the temporomandibular joint (TMJ) development and homeostasis in response to jaw loading. Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research 1 41051362
2023 The oligodontia phenotype in a X-linked hypohidrotic ectodermal dysplasia patient with a novel EVC2 variant. Heliyon 1 38163170
2022 Novel large deletion involving EVC and EVC2 in Ellis-van Creveld syndrome. Human genome variation 1 35581188
2025 Case Report: A novel compound heterozygosity of the EVC2 gene identified in a Chinese pedigree with congenital heart defect. Frontiers in pediatrics 0 40726901
2025 Oncogenic activation of EVC/EVC2 defines a therapeutically targetable subset of acute myeloid leukemia. Leukemia 0 41249566
2025 Identification of a Novel EVC2 Variant in a Family with Non-Syndromic Tooth Agenesis and Its Potential Functional Implications. Genes 0 41300740
2005 [From gene to disease; EVC, EVC2, and Ellis-van Creveld syndrome]. Nederlands tijdschrift voor geneeskunde 0 15884406