Affinage

NSDHL

Sterol-4-alpha-carboxylate 3-dehydrogenase, decarboxylating · UniProt Q15738

Length
373 aa
Mass
41.9 kDa
Annotated
2026-04-29
34 papers in source corpus 15 papers cited in narrative 15 extracted findings

Mechanistic narrative

Synthesis pass · prose summary of the discoveries below

NSDHL is a 3β-hydroxysterol dehydrogenase/C-3 sterol dehydrogenase that catalyzes the removal of C-4 methyl groups during post-squalene cholesterol biosynthesis, functioning upstream of EBP in the pathway; its enzymatic activity is confirmed by rescue of ERG26-deficient yeast and by direct enzyme inhibition studies with FR171456 (PMID:10710235, PMID:14567972, PMID:26456460). The protein localizes to ER membranes and lipid droplet surfaces via Golgi-dependent trafficking, and loss-of-function mutations cause CHILD syndrome while hypomorphic alleles with temperature-sensitive instability cause CK syndrome, with methylsterol accumulation rather than cholesterol deficiency implicated as the primary pathogenic mechanism (PMID:14506130, PMID:21129721). Beyond its metabolic role, NSDHL-derived cholesterol is essential for Hedgehog signaling in placental and cerebellar development, and NSDHL enzymatic activity sustains TGFβ signaling by preventing endosomal degradation of TGFβR2 and regulates EGFR trafficking (PMID:17028112, PMID:25652406, PMID:33864166, PMID:32140747). NSDHL also binds STING and promotes its ubiquitin-mediated degradation, thereby attenuating cGAS-STING innate immune signaling (PMID:39290276).

Mechanistic history

Synthesis pass · year-by-year structured walk · 11 steps
  1. 2000 High

    Identification of NSDHL as the gene mutated in CHILD syndrome established it as a cholesterol biosynthetic enzyme acting upstream of EBP, answering the long-standing question of the molecular basis of this X-linked ichthyosis.

    Evidence SSCA and genomic sequencing of CHILD syndrome patients with epistasis analysis relative to EBP/CDPX2

    PMID:10710235

    Open questions at the time
    • Precise enzymatic reaction mechanism not yet defined
    • Substrate specificity not characterized biochemically
    • Subcellular site of action unknown
  2. 2003 High

    Functional complementation of ERG26-deficient yeast by mouse NSDHL confirmed C-3 sterol dehydrogenase activity, while subcellular localization studies revealed dual ER membrane/lipid droplet targeting dependent on Golgi trafficking, establishing both enzymatic identity and cellular compartmentalization.

    Evidence Yeast rescue assays with multiple alleles; confocal microscopy of tagged NSDHL constructs with Golgi-disruption experiments

    PMID:14506130 PMID:14567972

    Open questions at the time
    • No structural information on NSDHL at this stage
    • Mechanism of Golgi-dependent ER targeting not defined
    • Functional role of lipid droplet localization unclear
  3. 2005 High

    Analysis of Nsdhl-null mouse embryos revealed midgestational lethality with placental labyrinth defects, demonstrating that NSDHL is essential for trophoblast proliferation and placental vascular development in vivo.

    Evidence Histological analysis and trophoblast proliferation assays in Nsdhl mutant mouse embryos

    PMID:15639195

    Open questions at the time
    • Molecular pathway linking NSDHL to trophoblast proliferation not identified
    • Whether cholesterol deficiency or sterol intermediate accumulation drives phenotype not resolved
  4. 2006 High

    Demonstration that NSDHL deficiency disrupts Indian hedgehog signaling in the placenta linked the cholesterol biosynthetic role to a specific developmental signaling pathway, explaining the trophoblast proliferation defect.

    Evidence Ptch1-lacZ reporter analysis in Nsdhl mutant placentas; mosaic analysis in heterozygous females

    PMID:17028112

    Open questions at the time
    • Whether cholesterol supply for Hh ligand modification is the direct mechanism not proven
    • Cell-autonomous vs. non-cell-autonomous signaling not fully dissected
  5. 2009 Medium

    Longitudinal mosaic analysis in heterozygous female mice showed progressive loss of NSDHL-negative cells in brain and liver, establishing a cell-autonomous survival requirement; transgenic rescue experiments further demonstrated that trophoblast-intrinsic NSDHL expression drives the placental phenotype.

    Evidence Immunohistochemistry across developmental stages in Bpa(1H)/+ mice; human NSDHL transgene rescue with placental area measurements

    PMID:19631568 PMID:19880419

    Open questions at the time
    • Mechanism of cell death in NSDHL-negative neurons not characterized
    • Contribution of imprinting vs. X-inactivation to phenotype not separated
  6. 2010 High

    Identification of CK syndrome mutations as hypomorphic, temperature-sensitive NSDHL alleles with normal cholesterol but methylsterol accumulation reframed the pathogenic mechanism from cholesterol deficiency to toxic sterol intermediate accumulation.

    Evidence Yeast complementation; temperature-sensitive protein stability assays; CSF and plasma sterol analysis in CK syndrome patients

    PMID:21129721

    Open questions at the time
    • Specific toxic methylsterol species not identified
    • Downstream targets of methylsterol toxicity unknown
    • Why CKS and CHILD syndrome differ phenotypically despite same gene not fully explained
  7. 2015 High

    Conditional CNS knockout revealed that NSDHL-derived cholesterol is required for SHH signaling in cerebellar granule cell precursors, with exogenous cholesterol rescuing proliferation defects — directly linking the enzyme's metabolic product to postnatal brain development and hedgehog pathway activation.

    Evidence Conditional Nsdhl knockout (GFAP-cre); in vitro GCP proliferation assay with cholesterol rescue; sterol measurements

    PMID:25652406

    Open questions at the time
    • Whether cholesterol acts via SHH ligand modification or smoothened activation not resolved
    • Whether methylsterol accumulation contributes independently to cell death not separated from cholesterol deficiency
  8. 2015 High

    Genome-wide haploinsufficiency profiling identified FR171456 as a direct NSDHL/Erg26p inhibitor, with resistance mutations mapping the enzyme's active site and providing the first pharmacological tool for NSDHL.

    Evidence Yeast haploinsufficiency screen; enzyme inhibition assays; resistance mutation mapping; sterol profiling

    PMID:26456460

    Open questions at the time
    • Inhibitor selectivity in mammalian systems not fully characterized
    • No co-crystal structure of NSDHL with inhibitor
  9. 2020 High

    Crystal structures of human NSDHL revealed the coenzyme-binding site and a conformational change upon binding, enabling structure-based discovery of a novel inhibitor that suppresses EGFR trafficking — expanding NSDHL's functional scope beyond cholesterol synthesis to receptor trafficking regulation.

    Evidence X-ray crystallography; structure-based virtual screening; EGFR trafficking cell-based assays

    PMID:32140747

    Open questions at the time
    • Mechanism by which NSDHL activity controls EGFR trafficking not defined
    • Whether EGFR regulation is direct or mediated by sterol intermediates unknown
  10. 2021 High

    In vivo CRISPR screening and catalytic-mutant rescue experiments demonstrated that NSDHL's enzymatic activity prevents endosomal degradation of TGFβR2, thereby sustaining TGFβ signaling and promoting breast cancer metastasis — establishing a catalysis-dependent, non-canonical signaling function.

    Evidence Pooled in vivo CRISPR screen; NSDHL knockdown and Y151X catalytic mutant; TGFβR2 degradation assays; ketoconazole rescue; orthotopic models

    PMID:33864166

    Open questions at the time
    • Whether sterol intermediates or cholesterol membrane composition mediates TGFβR2 stabilization unknown
    • Endosomal sorting mechanism not characterized
  11. 2024 Medium

    Co-immunoprecipitation and ubiquitination studies showed NSDHL physically binds STING and promotes its ubiquitin-dependent degradation, identifying a non-enzymatic role in suppressing cGAS-STING innate immune signaling.

    Evidence Co-IP of NSDHL-STING; ubiquitination assays; IFNβ measurements in cholangiocarcinoma cells

    PMID:39290276

    Open questions at the time
    • No reciprocal IP or endogenous IP reported
    • E3 ligase mediating STING ubiquitination in this context not identified
    • Whether this function is independent of NSDHL enzymatic activity not tested

Open questions

Synthesis pass · forward-looking unresolved questions
  • Key unresolved questions include the precise sterol intermediate(s) responsible for toxicity in CHILD/CK syndrome, the mechanism by which NSDHL metabolic activity controls receptor trafficking (TGFβR2, EGFR), and whether the STING-binding function represents a bona fide non-enzymatic role or is secondary to altered membrane sterol composition.
  • Toxic methylsterol species identity unknown
  • Structural basis for NSDHL-STING interaction not defined
  • No systematic separation of enzymatic vs. non-enzymatic functions across signaling phenotypes

Mechanism profile

Synthesis pass · controlled-vocabulary classification · explore literature graph →
Molecular activity
GO:0016491 oxidoreductase activity 4 GO:0016829 lyase activity 2
Localization
GO:0005783 endoplasmic reticulum 1 GO:0005794 Golgi apparatus 1 GO:0005811 lipid droplet 1
Pathway
R-HSA-1430728 Metabolism 6 R-HSA-1266738 Developmental Biology 4 R-HSA-162582 Signal Transduction 4 R-HSA-1643685 Disease 4
Partners
STING1TGFBR2

Evidence

Reading pass · 15 per-paper findings extracted from the source corpus
Year Finding Method Journal Conf PMIDs
2000 NSDHL encodes a 3β-hydroxysteroid dehydrogenase functioning in the cholesterol biosynthetic pathway; loss-of-function mutations in NSDHL cause CHILD syndrome, and the protein functions upstream of EBP (delta8-delta7 sterol isomerase) in cholesterol biosynthesis. SSCA and genomic sequence analysis of NSDHL in CHILD syndrome patients; genetic epistasis with EBP (CDPX2 gene) established pathway position American journal of medical genetics High 10710235
2003 NSDHL protein localizes to ER membranes and to the surface of lipid droplets, and trafficking through the Golgi is necessary for ER membrane localization; the dual localization was demonstrated using tagged wild-type and mutant murine Nsdhl alleles. Confocal microscopy of tagged NSDHL constructs (wild-type and mutant); Golgi trafficking disruption experiments Human molecular genetics High 14506130
2003 Mouse NSDHL protein can rescue lethality of erg26-deficient Saccharomyces cerevisiae cells (lacking the yeast ortholog), confirming NSDHL functions as a C-3 sterol dehydrogenase; hypomorphic alleles showed partial complementation while null alleles showed none. Functional complementation assay in Erg26-deficient yeast; in vivo rescue of yeast lethality Molecular genetics and metabolism High 14567972
2005 Nsdhl-deficient male mouse embryos die in midgestation (E10.5–13.5) with placental labyrinth defects: thinner labyrinth layer, fewer fetal vessels, and decreased proliferation of labyrinth trophoblast cells, implicating NSDHL in placental vascular development. Analysis of Nsdhl mutant mouse embryos by histology; trophoblast proliferation assays Molecular genetics and metabolism High 15639195
2006 NSDHL deficiency in mouse embryos disrupts Indian hedgehog (Ihh) signaling in the placenta; Ptch1-lacZ reporter expression was markedly decreased in Nsdhl mutant placentas, and Ihh-expressing cells failed to migrate into allantoic mesoderm, establishing a role for NSDHL-dependent cholesterol biosynthesis in placental hedgehog signaling. Transgenic Ptch1-lacZ reporter mouse; X-linked lacZ mosaic analysis; histology of mutant placentas Human molecular genetics High 17028112
2009 NSDHL-deficient cells in heterozygous Bpa(1H)/+ female mice are subject to negative selection over time; clonal NSDHL-negative cells decline from ~50% to ~20% in liver and brain over the first year of life, demonstrating a cell-autonomous requirement for NSDHL in neuronal and hepatocyte survival. Immunohistochemistry for NSDHL across multiple tissue types and developmental stages in wild-type and Bpa(1H) mice Molecular genetics and metabolism Medium 19631568
2009 Trophoblast-lineage expression of Nsdhl (from the maternally inherited allele) has the largest effect on placental area in Nsdhl mutant conceptuses; maternal genotype independently contributes a smaller effect on placental development, demonstrating non-cell-autonomous and imprinting-related roles for NSDHL in placentation. Transgenic rescue experiments (human NSDHL transgene rescuing male lethality); placental area measurements at E10.5 comparing maternal vs. paternal transmission Human molecular genetics Medium 19880419
2010 Hypomorphic NSDHL mutations (p.Lys232del and p.Arg367SerfsX33) cause CK syndrome through temperature-sensitive protein instability; these mutations alter protein folding and show complementation in Erg26-deficient yeast; methylsterol accumulation (not cholesterol deficiency) is hypothesized as the pathogenic mechanism, as CSF and plasma cholesterol levels are normal in CKS patients. Yeast complementation assay; temperature-sensitive protein stability assays; sterol analysis of CSF and plasma American journal of human genetics High 21129721
2015 Conditional ablation of Nsdhl in radial glia (GFAP-cre) causes defective SHH signaling in cerebellar granule cell precursors, resulting in proliferation defects that are rescued by exogenous cholesterol supplementation; methylsterol accumulation above the enzymatic block is associated with increased cell death, establishing that NSDHL-derived cholesterol is required for SHH signaling in postnatal CNS. Conditional knockout mouse (Nsdhl(tm1.1Hrm) × GFAP-cre); in vitro granule cell precursor proliferation assay; cholesterol rescue experiment; sterol level measurements Human molecular genetics High 25652406
2015 FR171456 specifically inhibits NSDHL (and its yeast ortholog Erg26p) enzymatic activity; multiple ERG26 mutations confer resistance to FR171456 in growth and enzyme assays, identifying the binding site on the enzyme. Genome-wide yeast haploinsufficiency profiling; enzyme inhibition assays; resistance mutation mapping; sterol intermediate profiling in human and yeast cells Nature communications High 26456460
2020 Two X-ray crystal structures of human NSDHL were solved, revealing a coenzyme-binding site and a unique conformational change upon coenzyme binding; structure-based virtual screening identified a novel NSDHL inhibitor with suppressive activity toward EGFR trafficking, establishing that NSDHL regulates EGFR trafficking pathways. X-ray crystallography; structure-based virtual screening; biochemical inhibition assays; cell-based EGFR trafficking assays Cellular and molecular life sciences : CMLS High 32140747
2021 NSDHL promotes triple-negative breast cancer metastasis by inhibiting endosomal degradation of TGFβR2, thereby activating the TGFβ signaling pathway; this function depends on NSDHL's enzymatic activity in cholesterol biosynthesis, as the catalytically inactive Y151X mutant did not rescue migration or TGFβR2 expression; blocking upstream NSDHL metabolism with ketoconazole rescued cancer metastasis. CRISPR pooled in vivo screen; Transwell migration assay; animal experiments; NSDHL knockdown and catalytic mutant (Y151X); TGFβR2 degradation assay; ketoconazole treatment Breast cancer research and treatment High 33864166
2020 NSDHL knockdown in 3T3-L1 cells attenuates adipogenesis, reduces lipid accumulation, downregulates PPARγ expression, and decreases LXR-SREBP1 signaling pathway activity, identifying NSDHL as a regulator of adipogenic differentiation through the LXR-SREBP1 axis. NSDHL knockdown in 3T3-L1 cells; quantitative RT-PCR; Oil Red O lipid staining; LXR-SREBP1 pathway analysis Bioscience, biotechnology, and biochemistry Medium 31985358
2024 NSDHL binds to STING protein and facilitates its degradation via ubiquitination, thereby inhibiting the cGAS-STING signaling pathway and reducing IFNβ synthesis in cholangiocarcinoma cells. Co-immunoprecipitation (NSDHL-STING binding); ubiquitination assay; IFNβ measurement; NSDHL overexpression in cells Heliyon Medium 39290276
2024 NSDHL knockdown in MCF-7 tumor spheroids reduces TGF-β1 and TGF-β3 secretion, decreases Smad2/3 phosphorylation, and reduces SOX2 expression, suppressing breast cancer stem-like cell populations and tumor-initiating capacity in orthotopic xenograft models. NSDHL knockdown; tumor spheroid formation assay; RNA sequencing; flow cytometry for BCSC markers; orthotopic xenograft model; ELISA for TGF-β BMC cancer Medium 39516821

Source papers

Stage 0 corpus · 34 papers · ranked by NIH iCite citations
Year Title Journal Citations PMID
2000 Mutations in the NSDHL gene, encoding a 3beta-hydroxysteroid dehydrogenase, cause CHILD syndrome. American journal of medical genetics 191 10710235
2003 NSDHL, an enzyme involved in cholesterol biosynthesis, traffics through the Golgi and accumulates on ER membranes and on the surface of lipid droplets. Human molecular genetics 84 14506130
2010 Hypomorphic temperature-sensitive alleles of NSDHL cause CK syndrome. American journal of human genetics 43 21129721
2002 A novel missense mutation of NSDHL in an unusual case of CHILD syndrome showing bilateral, almost symmetric involvement. Journal of the American Academy of Dermatology 37 11907515
2021 NSDHL promotes triple-negative breast cancer metastasis through the TGFβ signaling pathway and cholesterol biosynthesis. Breast cancer research and treatment 33 33864166
2015 Analysis of hedgehog signaling in cerebellar granule cell precursors in a conditional Nsdhl allele demonstrates an essential role for cholesterol in postnatal CNS development. Human molecular genetics 28 25652406
2003 Left-sided CHILD syndrome caused by a nonsense mutation in the NSDHL gene. American journal of medical genetics. Part A 28 12966526
2018 RNA-Seq analysis reveals a negative role of MSMO1 with a synergized NSDHL expression during adipogenesis of 3T3-L1. Bioscience, biotechnology, and biochemistry 23 30582412
2006 Analysis of Nsdhl-deficient embryos reveals a role for Hedgehog signaling in early placental development. Human molecular genetics 21 17028112
2005 Placental defects are associated with male lethality in bare patches and striated embryos deficient in the NAD(P)H Steroid Dehydrogenase-like (NSDHL) Enzyme. Molecular genetics and metabolism 20 15639195
2005 CHILD syndrome caused by a deletion of exons 6-8 of the NSDHL gene. Dermatology (Basel, Switzerland) 18 16088165
2023 Regorafenib enhances anti-tumor efficacy of immune checkpoint inhibitor by regulating IFN-γ/NSDHL/SREBP1/TGF-β1 axis in hepatocellular carcinoma. Biomedicine & pharmacotherapy = Biomedecine & pharmacotherapie 17 36669362
2003 Identification of two novel mutations in the murine Nsdhl sterol dehydrogenase gene and development of a functional complementation assay in yeast. Molecular genetics and metabolism 17 14567972
2017 A Large Deletion in the NSDHL Gene in Labrador Retrievers with a Congenital Cornification Disorder. G3 (Bethesda, Md.) 16 28739597
2009 Developmental expression pattern of the cholesterogenic enzyme NSDHL and negative selection of NSDHL-deficient cells in the heterozygous Bpa(1H)/+ mouse. Molecular genetics and metabolism 16 19631568
2020 Crystal structures of human NSDHL and development of its novel inhibitor with the potential to suppress EGFR activity. Cellular and molecular life sciences : CMLS 14 32140747
2015 FR171456 is a specific inhibitor of mammalian NSDHL and yeast Erg26p. Nature communications 13 26456460
2009 CHILD syndrome: the NSDHL gene and its role in CHILD syndrome, a rare hereditary disorder. Journal of the European Academy of Dermatology and Venereology : JEADV 13 19906044
2019 Identification of NSDHL mutations associated with CHILD syndrome in oral verruciform xanthoma. Oral surgery, oral medicine, oral pathology and oral radiology 10 31078502
2019 A missense variant in the NSDHL gene in a Chihuahua with a congenital cornification disorder resembling inflammatory linear verrucous epidermal nevi. Animal genetics 8 31571289
2022 Etiological identification of recurrent male fatality due to a novel NSDHL gene mutation using trio whole-exome sequencing: A rare case report and literature review. Molecular genetics & genomic medicine 7 36504312
2020 Novel variant in NSDHL gene associated with CHILD syndrome and syndactyly- a case report. BMC medical genetics 7 32819291
2015 A novel missense mutation in the NSDHL gene identified in a Lithuanian family by targeted next-generation sequencing causes CK syndrome. American journal of medical genetics. Part A 7 25900314
2018 NSDHL-containing duplication at Xq28 in a male patient with autism spectrum disorder: a case report. BMC medical genetics 6 30376821
2024 NSDHL contributes to breast cancer stem-like cell maintenance and tumor-initiating capacity through TGF-β/Smad signaling pathway in MCF-7 tumor spheroid. BMC cancer 5 39516821
2022 CPSF1 positively regulates NSDHL by alternative polyadenylation and promotes gastric cancer progression. American journal of cancer research 5 36381317
2020 Suppression of NSDHL attenuates adipogenesis with a downregulation of LXR-SREBP1 pathway in 3T3-L1 cells. Bioscience, biotechnology, and biochemistry 5 31985358
2020 Novel NSDHL gene variant for congenital hemidysplasia with ichthyosiform erythroderma and limb defects (CHILD) syndrome. BMJ case reports 5 33139364
2020 NSDHL Frameshift Deletion in a Mixed Breed Dog with Progressive Epidermal Nevi. Genes 5 33143176
2018 Genetic variant in the NSDHL gene in a cat with multiple congenital lesions resembling inflammatory linear verrucous epidermal nevi. Veterinary dermatology 5 30474267
2013 Identification of a novel polymorphism in X-linked sterol-4-alpha-carboxylate 3-dehydrogenase (Nsdhl) associated with reduced high-density lipoprotein cholesterol levels in I/LnJ mice. G3 (Bethesda, Md.) 4 23979938
2021 A novel NSDHL variant in CHILD syndrome with gastrointestinal manifestations and localized skin involvement. Molecular genetics & genomic medicine 3 34957706
2009 Significant contributions of the extraembryonic membranes and maternal genotype to the placental pathology in heterozygous Nsdhl deficient female embryos. Human molecular genetics 3 19880419
2024 NSDHL promotes the degradation of sting in cholangiocarcinoma. Heliyon 1 39290276