Affinage

HAS3

Hyaluronan synthase 3 · UniProt O00219

Length
553 aa
Mass
63.0 kDa
Annotated
2026-04-28
25 papers in source corpus 16 papers cited in narrative 16 extracted findings

Mechanistic narrative

Synthesis pass · prose summary of the discoveries below

HAS3 is a plasma membrane-localized hyaluronan synthase that catalyzes HA synthesis from UDP-GlcNAc and UDP-GlcUA with uniquely high efficiency at low substrate concentrations, and whose activity shapes extracellular matrix composition, cell surface architecture, and intercellular signaling (PMID:23303191, PMID:24790187). HAS3 traffics between the plasma membrane and endosomes under Rab10 GTPase control, with UDP-GlcNAc availability governing O-GlcNAcylation-dependent retention at the cell surface versus lysosomal degradation, thereby coupling cellular metabolic state to HA output (PMID:26883802, PMID:24509846). HAS3 forms homo- and heteromeric complexes with HAS1 and HAS2 through N-terminal domains, is transcriptionally regulated by Sp1, NFκB, FOSL1, NFAT1, and RAR signaling, and is post-transcriptionally repressed by miR-10b and miR-29a (PMID:25795779, PMID:25843802, PMID:38402581, PMID:41851636, PMID:31948751). Its HA product drives plasma membrane protrusion formation, modulates cell adhesion and migration via CD44, regulates brain extracellular space volume—with Has3 knockout causing reduced hippocampal ECS and epileptiform activity—and is shed in extracellular vesicles carrying IHH to activate hedgehog signaling in recipient cells (PMID:26162854, PMID:26222208, PMID:24790187, PMID:31820036).

Mechanistic history

Synthesis pass · year-by-year structured walk · 11 steps
  1. 2006 Low

    Early pharmacological evidence linked HAS3-dependent HA production to tumor cell proliferation and invasion, raising the question of which HAS isoenzyme drives pro-metastatic HA synthesis.

    Evidence 4-methylumbelliferone inhibition of HA synthesis in LM8 osteosarcoma cells with proliferation/invasion readouts

    PMID:16773198

    Open questions at the time
    • 4-methylumbelliferone is not HAS3-specific, so isoform attribution is uncertain
    • no genetic ablation or rescue performed
    • molecular weight specificity of HA product not rigorously controlled
  2. 2011 Medium

    HAS3 overexpression disrupted epithelial polarity and lumen formation, establishing that excess HA production at both apical and basolateral surfaces interferes with cell-cell junction integrity and mitotic spindle orientation.

    Evidence Stable GFP-HAS3 expression in MDCK 3D cyst cultures with junction protein immunostaining and spindle orientation analysis

    PMID:22159845

    Open questions at the time
    • overexpression system may not reflect physiological HAS3 levels
    • endogenous HAS3 contribution to epithelial polarity not tested
  3. 2013 High

    Quantitative substrate utilization studies resolved a longstanding question about isoenzyme specificity, showing HAS3 operates at maximal speed even at minimal UDP-GlcNAc concentrations, consuming enough UDP-sugars to deplete cellular pools.

    Evidence Side-by-side transfection of HAS1-3 in COS-1 cells with UDP-sugar quantification under varying glucosamine/glucose conditions

    PMID:23303191

    Open questions at the time
    • kinetic parameters not determined with purified enzyme
    • in vivo relevance of substrate depletion not established
  4. 2013 Medium

    RAR-mediated transcriptional control of HAS3 was identified, showing that lutein metabolites activate RAR to induce HAS3 expression in keratinocytes.

    Evidence RAR antagonist (LE540) and retinal dehydrogenase inhibitor (citral) treatment with RARE reporter assay and HAS3 mRNA quantification in human keratinocytes

    PMID:23748778

    Open questions at the time
    • direct RAR binding to HAS3 promoter not shown by ChIP
    • specific lutein metabolite acting as RAR ligand not identified
  5. 2014 High

    Two studies revealed HAS3's physiological roles in trafficking and brain function: Rab10 was identified as the GTPase controlling HAS3 endocytosis from the plasma membrane, while Has3 knockout mice demonstrated that HAS3-derived HA maintains hippocampal extracellular space volume, with its loss causing epileptiform activity.

    Evidence Co-IP from endosomal fractions and Rab10 siRNA/overexpression in cell culture; Has3−/− mice with iontophoretic ECS measurement, electrophysiology, and osmotic rescue

    PMID:24509846 PMID:24790187

    Open questions at the time
    • Rab10-HAS3 binding interface not mapped
    • whether HA molecular weight differs regionally in brain not addressed
    • human genetic evidence linking HAS3 to epilepsy not available
  6. 2015 High

    Multiple discoveries in this year built a comprehensive picture of HAS3 regulation and downstream signaling: HAS3 forms homo/heteromeric complexes with HAS1/HAS2 via N-terminal domains; its promoter was mapped to a 450-bp proximal region requiring Sp1; and overexpression studies showed HAS3-driven HA induces filopodia-like protrusions and dorsal ruffles, while suppressing ERK1/2 signaling and CD44-dependent cell adhesion/migration.

    Evidence FRET and PLA for complex formation with domain mutagenesis; promoter deletion/mutagenesis with reporter assays; GFP-HAS3 overexpression with cytoskeletal marker analysis and CLEM; inducible overexpression with hyaluronidase/HA oligosaccharide rescue and ERK phosphorylation assays

    PMID:25795779 PMID:25843802 PMID:26162854 PMID:26222208 PMID:26448759

    Open questions at the time
    • stoichiometry of HAS homo/heteromeric complexes unknown
    • structural basis for N-terminal interaction not resolved
    • whether protrusion formation occurs at endogenous HAS3 levels not tested
  7. 2016 High

    The metabolic sensing mechanism for HAS3 activity was elucidated: UDP-GlcNAc availability controls O-GlcNAcylation of HAS3, which determines whether HAS3 is retained at the plasma membrane or endocytosed for lysosomal degradation, coupling cellular metabolic state to HA output.

    Evidence Live cell imaging, flow cytometry, O-GlcNAc modification assays, and inhibitor experiments in GFP-HAS3-expressing melanoma cells

    PMID:26883802

    Open questions at the time
    • specific O-GlcNAcylated residues on HAS3 not mapped
    • whether O-GlcNAcylation directly prevents Rab10 binding not tested
  8. 2019 Medium

    HAS3-induced extracellular vesicles were shown to carry IHH cargo that activates hedgehog signaling in recipient cells, establishing a paracrine signaling function for HAS3-derived EVs beyond simple HA delivery.

    Evidence EV isolation from GFP-HAS3-overexpressing melanoma cells, proteomics, hedgehog pathway inhibition, and target cell proliferation/invasion assays

    PMID:31820036

    Open questions at the time
    • mechanism of IHH loading onto HAS3-EVs unknown
    • whether endogenous HAS3 levels produce EVs with similar cargo not established
  9. 2020 Medium

    Post-transcriptional regulation of HAS3 was defined: miR-10b and miR-29a directly target the HAS3 3′UTR to repress its expression during neuroendocrine transdifferentiation of prostate cancer cells.

    Evidence 3′UTR reporter assays, miRNA overexpression, western blotting, and functional assays in LNCaP cells

    PMID:31948751

    Open questions at the time
    • whether these miRNAs regulate HAS3 in non-cancer contexts unknown
    • endogenous miRNA-HAS3 interaction not validated by CLIP
  10. 2024 Medium

    FOSL1 was placed as a direct transcriptional activator of HAS3 in head and neck cancer, with melatonin suppressing this axis to reduce cancer stem cell properties including CD44 expression and tumor-initiating frequency.

    Evidence FOSL1 knockdown/overexpression, HAS3 expression analysis, CD44/CSC marker assays, and in vivo tumor-initiating frequency in HNSCC cells

    PMID:38402581

    Open questions at the time
    • direct FOSL1 binding to HAS3 promoter not confirmed by ChIP
    • melatonin receptor independence mechanism not fully explained
  11. 2026 Medium

    NFAT1 was identified as a transcriptional activator of HAS3 in microglia, with HAS3-derived HA signaling through LYVE1 in an autocrine loop to activate Wnt/β-catenin and promote anti-inflammatory polarization and angiogenesis after ischemic stroke.

    Evidence Nfat1−/− mice, ChIP and dual-luciferase reporter assay, conditioned medium experiments, microglia transplantation with MRI

    PMID:41851636

    Open questions at the time
    • LYVE1-Wnt connection mechanism not fully delineated
    • whether HAS3 is the dominant HAS isoform in microglia in vivo not established

Open questions

Synthesis pass · forward-looking unresolved questions
  • Key unresolved questions include: the structural basis of HAS3 catalysis and oligomerization, the identity of specific O-GlcNAcylation sites controlling trafficking, the mechanism by which HAS3-EVs selectively load IHH, and whether HAS3 loss-of-function variants contribute to human neurological disease.
  • no crystal or cryo-EM structure available
  • O-GlcNAc site mapping on HAS3 not performed
  • human genetic studies linking HAS3 variants to epilepsy absent

Mechanism profile

Synthesis pass · controlled-vocabulary classification · explore literature graph →
Molecular activity
GO:0016740 transferase activity 3 GO:0140657 ATP-dependent activity 1
Localization
GO:0005886 plasma membrane 5 GO:0031410 cytoplasmic vesicle 3 GO:0005768 endosome 2 GO:0005576 extracellular region 1 GO:0005794 Golgi apparatus 1
Pathway
R-HSA-74160 Gene expression (Transcription) 4 R-HSA-1474244 Extracellular matrix organization 3 R-HSA-162582 Signal Transduction 3 R-HSA-5653656 Vesicle-mediated transport 3 R-HSA-112316 Neuronal System 1
Partners
CD44FOSL1HAS1HAS2IHHLYVE1NFAT1RAB10
Complex memberships
HAS1/HAS2/HAS3 homo- and heteromeric complexes

Evidence

Reading pass · 16 per-paper findings extracted from the source corpus
Year Finding Method Journal Conf PMIDs
2013 HAS3 produces hyaluronan at high speed even with minimum UDP-GlcNAc substrate concentration, in contrast to HAS1 (which requires ~10-fold higher UDP-GlcNAc) and HAS2 (intermediate requirement). Transfected HAS3 consumed enough UDP-sugars to reduce their cellular content in COS-1 cells. Transfection of COS-1 cells with human HAS1-3 isoenzymes, glucosamine supplementation, glucose-free medium experiments, UDP-sugar quantification The Journal of biological chemistry High 23303191
2016 HAS3 undergoes rapid recycling between plasma membrane and endosomes; depletion of UDP-GlcNAc or UDP-GlcUA shifts the balance toward HAS3 endocytosis and lysosomal decay, while UDP-GlcNAc surplus suppresses endocytosis and promotes HAS3 retention at the plasma membrane and shedding in extracellular vesicles. UDP-GlcNAc concentration also controls the level of O-GlcNAc modification of HAS3, and increasing O-GlcNAcylation reproduces the effects of UDP-GlcNAc surplus on HAS3 trafficking. Live cell imaging, flow cytometry, inhibitor experiments, endocytosis assays, O-GlcNAc modification assays in melanoma cells expressing GFP-HAS3 Cellular and molecular life sciences : CMLS High 26883802
2014 Rab10 GTPase controls HAS3 endocytosis: Rab10 colocalizes with HAS3 in intracellular vesicular structures and is co-immunoprecipitated with HAS3 from isolated endosomal vesicles. Rab10 silencing increased plasma membrane residence of HAS3, resulting in increased HA secretion and enlarged cell surface HA coat, while Rab10 overexpression suppressed HA synthesis. The HAS3-driven cell surface HA coat impaired cell adhesion to type I collagen. Co-immunoprecipitation from endosomal fractions, Rab10 siRNA silencing, Rab10 overexpression, live cell imaging, collagen adhesion assay with hyaluronidase rescue The Journal of biological chemistry High 24509846
2015 HAS3 forms homomeric and heteromeric complexes with HAS1 and HAS2 both in the Golgi apparatus and plasma membrane. The enzymes interact primarily via an N-terminal 86-amino acid domain, with additional binding sites in C-terminal regions. HAS3 has the highest homomeric synthetic activity; HAS1 transfection reduces hyaluronan synthesis obtained by HAS2 and HAS3, indicating functional cooperation. FRET in live cells, acceptor photobleaching FRET microscopy, proximity ligation assay with endogenous HAS antibodies, C-terminal deletion mutagenesis The Journal of biological chemistry High 25795779
2014 Has3 knockout mice show ~40% selective reduction in extracellular space (ECS) volume in the CA1 stratum pyramidale of hippocampus, causing spontaneous epileptiform activity and increased cell packing density. Osmotic manipulation experiments established a causal link between ECS volume reduction and epileptiform activity. Has3-/- knockout mice, real-time iontophoretic method for ECS quantification, electrophysiology in brain slices, fluorescent marker diffusion imaging, osmotic manipulation experiments The Journal of neuroscience : the official journal of the Society for Neuroscience High 24790187
2015 HAS3 overexpression induces formation of long, slender plasma membrane protrusions that share cytoskeletal features of filopodia (enriched in filamentous actin, villin, ezrin, espin, fascin, Myo10) but are independent of substratum attachment due to extracellular scaffolding by hyaluronan. Hyaluronidase digestion causes immediate GFP-HAS3 escape from protrusions and collapse, suggesting hyaluronan chain maintains HAS3 at the plasma membrane. GFP-HAS3 overexpression in MCF-7 cells, immunostaining of actin-associated proteins, hyaluronidase treatment, live cell imaging, ultrastructural analysis Experimental cell research Medium 26162854
2015 CLEM (correlative light and electron microscopy) revealed that GFP-HAS3 not only localizes to plasma membrane ruffles but actively induces dorsal ruffle formation, linking HAS3-driven hyaluronan synthesis to dorsal membrane ruffling. Correlative light and electron microscopy (CLEM) of GFP-HAS3 expressing cells International journal of cell biology Medium 26448759
2011 HAS3 overexpression in MDCK cells causes HA accumulation at both apical and basolateral membrane domains, interfering with cell-cell junction formation, impairing epithelial barrier function, and causing aberrant mitotic spindle orientation leading to multiple small lumina instead of a single lumen in 3D cyst cultures. Stable GFP-HAS3 overexpression in MDCK cells, 3D cyst culture, immunostaining for junction proteins, barrier function assays, spindle orientation analysis Histochemistry and cell biology Medium 22159845
2019 HAS3-induced extracellular vesicles carry IHH (Indian Hedgehog), which activates the hedgehog signaling cascade in target cells, leading to c-Myc upregulation and increased claspin expression. CD44 participates in the regulation of EV binding to target cells. HAS3-EVs induce HA secretion, proliferation, and invasion of recipient cells. GFP-HAS3 overexpression in melanoma cells, EV isolation and treatment of target cells, hedgehog pathway inhibition, proteomics, immunostaining Cellular and molecular life sciences : CMLS Medium 31820036
2015 HAS3 overexpression in MV3 melanoma cells decreases ERK1/2 phosphorylation, and inhibits cell adhesion, migration (reversible by hyaluronidase or HA oligosaccharides blocking CD44), and proliferation (receptor-independent) via G1/G0 cell cycle arrest. Inducible HAS3 overexpression in MV3 cells, hyaluronidase treatment, HA oligosaccharide receptor blocking, ERK1/2 phosphorylation western blot, cell cycle analysis Experimental cell research Medium 26222208
2015 The HAS3 proximal promoter is restricted to a 450-bp region (-761 to -305 bp upstream of the major transcription start site), and the core promoter to a 129-bp region. The proximal Sp1 binding site is essential for robust proximal promoter activity, and the core MTE motif is required for basic core promoter activity. The HAS3 promoter lacks a canonical TATA box but contains GC boxes and putative C/EBP and NFκB binding sites. 5' RACE, progressive deletion analysis, site-directed mutagenesis of transcription factor binding sites, luciferase reporter assays Biochemical and biophysical research communications Medium 25843802
2013 Lutein activates the retinoic acid receptor (RAR) to induce HAS3 gene expression and downstream hyaluronan synthesis in human keratinocytes. RAR antagonist LE540 abolished lutein-dependent hyaluronan synthesis; citral (retinal dehydrogenase inhibitor) decreased lutein-stimulated hyaluronan synthesis, indicating that lutein metabolites rather than lutein itself act as RAR ligands. RAR antagonist (LE540) treatment, retinal dehydrogenase inhibitor (citral) treatment, RARE-driven reporter assay, HAS3 mRNA quantification in human keratinocytes Bioscience, biotechnology, and biochemistry Medium 23748778
2020 miR-10b and miR-29a directly repress HAS3 expression by binding to its 3'UTR in LNCaP prostate cancer cells undergoing neuroendocrine transdifferentiation. HAS3 inhibits cell proliferation and migration but increases colony-forming ability in these cells. Reporter gene assays with HAS3 3'UTR, western blotting, miRNA overexpression, cell proliferation/migration/colony assays Biochemical and biophysical research communications Medium 31948751
2024 Melatonin suppresses HAS3 expression through downregulation of the transcription factor FOSL1, thereby reducing HA synthesis and inhibiting cancer stem cell properties (CD44 expression, tumor-initiating frequency) of head and neck squamous cell carcinoma cells in a receptor-independent manner. Melatonin treatment of HNSCC cells, FOSL1 knockdown/overexpression, HAS3 expression analysis, CD44 and CSC marker assays, in vivo tumor-initiating frequency assay Journal of pineal research Medium 38402581
2026 NFAT1 transcriptionally upregulates HAS3 in microglia, driving HAS3-dependent HA production that signals via LYVE1 in an autocrine/paracrine manner to activate Wnt/β-catenin signaling, promoting anti-inflammatory microglial polarization and angiogenesis after ischemic stroke. Nfat1-/- knockout mice, ChIP assay, dual-luciferase reporter assay, conditioned medium experiments, NFAT1-overexpressing microglia transplantation, MRI, immunofluorescence Cellular & molecular biology letters Medium 41851636
2006 HAS3-produced hyaluronan (lower molecular weight) enhances osteosarcoma cell proliferation, invasion, and extracellular matrix degradation required for metastasis. Suppression of HAS3 activity with 4-methylumbelliferone inhibited cell proliferation and invasion in LM8 osteosarcoma cells. HAS3 inhibition with 4-methylumbelliferone, HA size fractionation, cell proliferation and invasion assays in LM8 osteosarcoma cells International journal of oncology Low 16773198

Source papers

Stage 0 corpus · 25 papers · ranked by NIH iCite citations
Year Title Journal Citations PMID
2003 EGF upregulates, whereas TGF-beta downregulates, the hyaluronan synthases Has2 and Has3 in organotypic keratinocyte cultures: correlations with epidermal proliferation and differentiation. The Journal of investigative dermatology 139 12787132
2014 Hyaluronan deficiency due to Has3 knock-out causes altered neuronal activity and seizures via reduction in brain extracellular space. The Journal of neuroscience : the official journal of the Society for Neuroscience 124 24790187
2013 Hyaluronan synthase 1 (HAS1) requires higher cellular UDP-GlcNAc concentration than HAS2 and HAS3. The Journal of biological chemistry 96 23303191
2016 UDP-sugar substrates of HAS3 regulate its O-GlcNAcylation, intracellular traffic, extracellular shedding and correlate with melanoma progression. Cellular and molecular life sciences : CMLS 50 26883802
2014 Extensive CD44-dependent hyaluronan coats on human bone marrow-derived mesenchymal stem cells produced by hyaluronan synthases HAS1, HAS2 and HAS3. The international journal of biochemistry & cell biology 49 24406795
2015 Fluorescence resonance energy transfer (FRET) and proximity ligation assays reveal functionally relevant homo- and heteromeric complexes among hyaluronan synthases HAS1, HAS2, and HAS3. The Journal of biological chemistry 36 25795779
2018 miR‑29a‑3p represses proliferation and metastasis of gastric cancer cells via attenuating HAS3 levels. Molecular medicine reports 27 29693123
2014 Rab10-mediated endocytosis of the hyaluronan synthase HAS3 regulates hyaluronan synthesis and cell adhesion to collagen. The Journal of biological chemistry 26 24509846
2006 HAS3-related hyaluronan enhances biological activities necessary for metastasis of osteosarcoma cells. International journal of oncology 26 16773198
2015 Cell protrusions induced by hyaluronan synthase 3 (HAS3) resemble mesothelial microvilli and share cytoskeletal features of filopodia. Experimental cell research 25 26162854
2019 HAS3-induced extracellular vesicles from melanoma cells stimulate IHH mediated c-Myc upregulation via the hedgehog signaling pathway in target cells. Cellular and molecular life sciences : CMLS 22 31820036
2011 HAS3-induced accumulation of hyaluronan in 3D MDCK cultures results in mitotic spindle misorientation and disturbed organization of epithelium. Histochemistry and cell biology 22 22159845
2013 Lutein, a nonprovitamin A, activates the retinoic acid receptor to induce HAS3-dependent hyaluronan synthesis in keratinocytes. Bioscience, biotechnology, and biochemistry 21 23748778
2015 Hyaluronan synthase 3 (HAS3) overexpression downregulates MV3 melanoma cell proliferation, migration and adhesion. Experimental cell research 19 26222208
2022 Targeting hyaluronic acid synthase-3 (HAS3) for the treatment of advanced renal cell carcinoma. Cancer cell international 18 36581895
2015 Identification and analysis of the promoter region of the human HAS3 gene. Biochemical and biophysical research communications 13 25843802
2020 The regulation of HAS3 by miR-10b and miR-29a in neuroendocrine transdifferentiated LNCaP prostate cancer cells. Biochemical and biophysical research communications 12 31948751
2015 Correlative Light and Electron Microscopy Reveals the HAS3-Induced Dorsal Plasma Membrane Ruffles. International journal of cell biology 10 26448759
2022 Cell-Type-Specific Expression of Hyaluronan Synthases HAS2 and HAS3 Promotes Goblet Cell Hyperplasia in Allergic Airway Inflammation. American journal of respiratory cell and molecular biology 8 35679095
2021 C1q-HA Matrix Regulates the Local Synthesis of Hyaluronan in Malignant Pleural Mesothelioma by Modulating HAS3 Expression. Cancers 8 33499323
2024 Melatonin inhibits the stemness of head and neck squamous cell carcinoma by modulating HA synthesis via the FOSL1/HAS3 axis. Journal of pineal research 7 38402581
2016 Localisation and endocrine control of hyaluronan synthase (HAS) 2, HAS3 and CD44 expression in sheep granulosa cells. Reproduction, fertility, and development 7 25427133
2022 Microscopic characterization reveals the diversity of EVs secreted by GFP-HAS3 expressing MCF7 cells. European journal of cell biology 6 35569384
2026 NFAT1+ microglia promote antiinflammatory polarization and angiogenesis via the HAS3-HA-LYVE1 axis to improve ischemic stroke outcomes. Cellular & molecular biology letters 0 41851636
2008 [Construction of eukaryotic expression vector of rat HAS-3 gene and its effects on chemotaxis]. Xi bao yu fen zi mian yi xue za zhi = Chinese journal of cellular and molecular immunology 0 18687209